AIM To investigate the relationship between protease production and the ability of Enterococcus faecalis strains to coexist in biofilms with other bacteria commonly recovered from infected root canals. METHODOLOGY: Biofilms with bacteria in mono-, dual- and four-species communities were developed in flow chambers. The organisms used were Lactobacillus salivarius, Streptococcus gordonii and Actinomyces naeslundii and E. faecalis strains, GUL1 and OG1RF. Biovolume and species distribution were examined using 16S rRNA fluorescence in situ hybridization in combination with confocal microscopy and image analysis. The full proteome of the E. faecalis strains was studied using two-dimensional gel electrophoresis. Spots of interest were identified using tandem mass spectroscopy and quantified using Delta 2D software. RESULTS: All bacteria formed biofilms and an anova analysis revealed that the biofilm biomass increased significantly (P ≤ 0.01) between 6 and 24 h. L. salivarius, S. gordonii and A. naeslundii formed mutualistic biofilm communities, and this pattern was unchanged when E. faecalis GUL1 was included in the consortium. However, with OG1RF, L. salivarius and S. gordonii were outcompeted in a 24-h biofilm. Proteomic analysis revealed that OG1RF secreted higher levels of proteases, GelE (P = 0.02) and SprE (P = 0.002) and a previously unidentified serine protease (P = 0.05), than GUL1. CONCLUSIONS: Different strains of E. faecalis can interact synergistically or antagonistically with a consortium of root canal bacteria. A possible mechanism underlying this, as well as potential differences in virulence, is production of different levels of proteases, which can cause detachment of neighbouring bacteria and tissue damage.

To determine whether bacteria isolated from infected root canals survive alkaline shifts better in biofilms than in planktonic cultures. METHODOLOGY: Clinical isolates of Enterococcus faecalis, Lactobacillus paracasei, Olsenella uli, Streptococcus anginosus, S. gordonii, S. oralis and Fusobacterium nucleatum in biofilm and planktonic cultures were stressed at pH 10.5 for 4 h, and cell viability determined using the fluorescent staining LIVE/DEAD BacLight bacterial viability kit. In addition, proteins released into extracellular culture fluids were identified by Western blotting. RESULTS: Enterococcus faecalis, L. paracasei, O. uli and S. gordonii survived in high numbers in both planktonic cultures and in biofilms after alkaline challenge. S. anginosus, S. oralis and F. nucleatum showed increased viability in biofilms compared with planktonic cultures. Alkaline exposure caused all planktonic cultures to aggregate into clusters and resulted in a greater extrusion of cellular proteins compared with cells in biofilms. Increased levels of DnaK, HPr and fructose-1,6-bisphosphate aldolase were observed in culture fluids, especially amongst streptococci. CONCLUSIONS: In general, bacteria isolated from infected roots canals resisted alkaline stress better in biofilms than in planktonic cultures, however, planktonic cells appeared to use aggregation and the extracellular transport of specific proteins as survival mechanisms.

Composite resin is used extensively for restoration of teeth with vital pulps. Although cell culture studies have disclosed harmful effects on pulpal cells, any untoward clinical effects, manifest as adverse pulpal responses, have yet to be determined. This study comprises a systematic review, designed to address the question of whether the risk of endodontic complications is greater with composite resin restorations than with other restorative materials, such as amalgam. The study methodology involved (i) formulation of the research question, (ii) construction and conduct of an extensive literature search with (iii) interpretation and assessment of the retrieved literature. A search of the medical database PubMed was complemented with a search of the Controlled Trials Register (CENTRAL). The initial search yielded 1043 publications, the abstracts of which were read independently by the authors. After additional searches, 10 studies were included in the review. In all the included studies, the level of evidence was assessed as low. No conclusions could therefore be drawn. The included studies reported few, if any, endodontic complications. Little or no differences emerged between teeth restored with composite resins and those restored with amalgam. To determine whether composite resin restorations of teeth with vital pulps are associated with an increased risk for development of endodontic complications such as apical periodontitis, further evidence is needed, from well-constructed studies with a large number of participants.

AIM: To describe the decision-making process of the general dental practitioner (GDP) underlying the choice of coronal restoration of a root filled tooth.

METHODOLOGY: GDPs were strategically selected with respect to gender, age, undergraduate dental school, service affiliation and duration of professional experience. Semi-structured in-depth interviews were conducted, focusing on the informant's personal experience of the process which leads to a decision as to how to restore a root filled tooth. The informants were invited to describe in their own words the latest two cases involving decisions of direct or full crown restorations respectively. The interviews were digitally recorded and transcribed verbatim. Interviews from 14 informants, aged 27 - 64 (mean age 46 years), were included and analyzed according to Qualitative Content Analysis.

RESULTS: A theme (latent content) was identified: Clinical factors were considered important but were overruled by context and patient opinions, if in conflict. Three main categories, including seven sub-categories (manifest content), were identified. The categories were clinical factors, contextual factors and patient´s views. Clinical factors underlying the GDPs´ decision included the current dental status and the estimated longevity of the intended restoration. In certain cases contextual factors were also of importance, either supporting the GDPs´ decision or modifying it. However, the patient´s views played a decisive role in the final choice of coronal restoration, leading to either mutual acceptance or a compromise, taking into account the patient´s economic status and opinions.

CONCLUSIONS: With respect to coronal restoration of a root filled tooth, the GDPs' decision-making process was based not only on clinical factors, but also on decisive contextual factors and consideration of the patients' views.

This position statement on the management of deep caries and the exposed pulp represents the consensus of an expert committee, convened by the European Society of Endodontology (ESE). Preserving the pulp in a healthy state with sustained vitality, preventing apical periodontitis and developing minimally invasive biologically based therapies are key themes within contemporary clinical endodontics. The aim of this statement is to summarise current best evidence on the diagnosis and classification of deep caries and caries-induced pulpal disease, as well as indicating appropriate clinical management strategies for avoiding and treating pulp exposure in permanent teeth with deep or extremely deep caries. In presenting these findings, areas of controversy, low-quality evidence and uncertainties are highlighted, prior to recommendations for each area of interest. A recently published review article provides more detailed information, and was the basis for this position statement (Bjørndal et al. 2019, International Endodontic Journal). The intention of this position statement is to provide the practitioner with relevant clinical guidance in this rapidly developing area. An update will be provided within 5 years as further evidence emerges. This article is protected by copyright. All rights reserved.

Background: The ESE previously published quality guidelines for endodontic treatment in 2006; however, there have been significant changes since not only in clinical endodontics but also in consensus and guideline development processes. In the development of the inaugural S3-level clinical practice guidelines (CPG), a comprehensive systematic and methodologically robust guideline consultation process was followed in order to produce evidence-based recommendations for the management of patients presenting with pulpal and apical disease.

Aim: To develop an S3-level CPG for the treatment of pulpal and apical disease, focusing on diagnosis and the implementation of the treatment approaches required to manage patients presenting with pulpitis and apical periodontitis (AP) with the ultimate goal of preventing tooth loss.

Methods: This S3-level CPG was developed by the ESE, with the assistance of independent methodological guidance provided by the Association of Scientific Medical Societies in Germany and utilizing the GRADE process. A robust, rigorous and transparent process included the analysis of relevant comparative research in 14 specifically commissioned systematic reviews, prior to evaluation of the quality and strength of evidence, the formulation of specific evidence and expert-based recommendations in a structured consensus process with leading endodontic experts and a broad base of external stakeholders.

Results: The S3-level CPG for the treatment of pulpal and apical disease describes in a series of clinical recommendations the effectiveness of diagnosing pulpitis and AP, prior to investigating the effectiveness of endodontic treatments in managing those diseases. Therapeutic strategies include the effectiveness of deep caries management in cases with, and without, spontaneous pain and pulp exposure, vital versus nonvital teeth, the effectiveness of root canal instrumentation, irrigation, dressing, root canal filling materials and adjunct intracanal procedures in the management of AP. Prior to treatment planning, the critical importance of history and case evaluation, aseptic techniques, appropriate training and re-evaluations during and after treatment is stressed.

Conclusion: The first S3-level CPG in endodontics informs clinical practice, health systems, policymakers, other stakeholders and patients on the available and most effective treatments to manage patients with pulpitis and AP in order to preserve teeth over a patient's lifetime, according to the best comparative evidence currently available.

Background: Development of a standardized set of topic-specific outcomes known as a Core Outcome Set (COS) is important to address issues of heterogeneity in reporting research findings in order to streamline evidence synthesis and clinical decision making.

Aim: The aim of the current international consensus study is to identify "what" outcomes to include in the Core Outcome Set for Endodontic Treatments (COSET). Outcomes of various endodontic treatments (non-surgical root canal treatment, surgical endodontics, vital pulp treatment and revitalization procedures) performed on permanent teeth were considered.

Methods: A standard validated methodology for COS development and reporting was adopted. The process involved identification of existing outcomes through four published scoping reviews. This enabled creation of a list of outcomes to be prioritized via semi-structured patient interviews, e-Delphi process and a consensus meeting with a range of relevant global stakeholders. Outcomes were prioritized using a 1-9 Likert scale, with outcomes rated 7-9 considered critical, 4-6 are important and 1-3 are less important. Outcomes rated 7-9 by ≥70% and 1-3 by <15% of participants were considered to achieve consensus for inclusion in the COS. The outcomes that did not achieve consensus in the first round were considered for further prioritization in the second Delphi round and consensus meeting. Final decisions about the outcomes to include in COSET were made by voting during the consensus panel meeting using the Zoom Poll function.

Results: A total of 95 participants including patients contributed to the COS development process. The consensus panel recommended, with strong consensus, eight outcomes shared across all treatment modalities for inclusion in COSET: pain; signs of infection (swelling, sinus tract); further intervention/exacerbation; tenderness to percussion/palpation; radiographic evidence of disease progression/healing; function; tooth survival; and patient satisfaction. Additional treatment specific outcomes were also recommended.

Discussion: Many of the outcomes included in COSET are patient reported. All should be included in future outcomes studies.

Conclusion: COSET identified outcomes that are important for patients and clinicians and validated these using a rigorous methodology. Further work is ongoing to determine "how" and "when" these outcomes should be measured.

There are several measures that are, or could be, in use in relation to estimating the outcome of endodontic treatments. It is important to reflect on when and why a certain outcome measure is used; when caring for an individual patient it is obvious that the goal always should be a tooth in a healthy state, that is striving to remove any infection and aim for the tooth to have healthy periapical tissues. For patients in general and for society, it is also interesting to know if endodontic treatments will lead to retention of teeth in a functioning state. From epidemiological studies, with high prevalence of root filled teeth with periapical radiolucencies, it is implied that dentists and/or patients accept the retention of a root filled tooth with persistent apical periodontitis. However, we do not know if or how this affects the health of the individual. In conjunction with an endodontic treatment the prognosis is considered and since the prognostic factors seem to be somewhat different depending on whether one is considering for example the outcome ´healthy periapical tissues´ or ´tooth survival´ they are equally important to know. Factors affecting the outcome ´healthy periapical tissues´ probably has to do with removal of infection and reconstituting the barrier to prevent leakage whilst ´tooth survival´ is more likely associated with factors outside of the classical endodontic field such as restorability and avoidance of further destruction of tooth substance. This narrative review will focus on tooth survival after endodontic treatment and root canal treatment will be the focus. As a crude estimation, there is to be an annual loss of 2% of teeth which have received a root canal treatment. Of the pre-, peri- and postoperative factors that have been studied in conjunction with root canal treatments the restoration of the tooth is the factor that has been most extensively studied. Many studies imply that root filled teeth restored with indirect restorations have a better survival than teeth restored with direct restorations, it is not possible to determine whether this indeed is a prognostic factor.

The aim was to evaluate the efficacy of various types of lasers used as an adjunct to chemo-mechanical disinfection of infected root canals with the outcome measures 'normal periapical condition' or 'reduction of microbial load'. PubMed, CENTRAL and ISI Web of Knowledge literature searches with specific indexing terms and a subsequent hand search were made with stated limits and criteria. Relevant publications were retrieved, followed by interpretation. The quality of each included publication was assessed as high, moderate or low. The initial search process yielded 234 publications. All abstracts of these publications were read, and the reference lists of relevant publications were hand-searched. Ten articles were read in full text and interpreted according to a data extraction form. Five were included in the systematic review and were assessed. A meta-analysis was impossible to perform because the included studies were heterogeneous with regard to study design, treatment and outcome measures. Positive effects were reported; however, no concluding evidence grade could be made because each included study was judged to have low quality, primarily due to lack of a power analysis, blinding and reproducibility. The evidence grade for whether lasers can be recommended as an adjunct to chemo-mechanical disinfection of infected root canals was insufficient. This does not necessarily imply that laser should not be used as an adjunct to root canal treatment but instead underscores the need for future high-quality studies.

Aim To characterize the hard tissue formed in human teeth experimentally pulp capped either with calcium hydroxide or with Emdogain®Gel (Biora AB, Malmö, Sweden) – , a derivative of enamel matrix (EMD), using two markers for dentine; dentine sialoprotein (DSP) and type 1 collagen (Col I). Formation of hard tissue following pulp capping in these teeth has previously been observed and reported. Methodology Affinity-purified rabbit anti-Col I and anti-DSP polyclonal antibodies were used to stain histological sections from 9 pairs of contra-lateral premolars, that had been experimentally pulp amputated and randomly capped with EMDgel or calcium hydroxide. The teeth were extracted 12 weeks after being pulp capped. Results In the calcium hydroxide treated teeth DSP was seen in the new hard tissue which formed a bridge. DSP was also seen in the newly formed hard tissue in the EMDgel treated teeth. Proliferated pulp tissue partly filled the space initially occupied by EMDgel and DSP-stained hard tissue was observed alongside exposed dentine surfaces as well as in isolated masses within the proliferated pulp tissue, although the new hard tissue did not cover the pulp exposure. DSP staining was also seen in the cells lining the hard tissue in both groups. Col I staining was seen in the newly formed hard tissue in both groups. Conclusions The new hard tissue formed after pulp capping with EMDgel or calcium hydroxide contained DSP and Col I, considered to be markers for dentine.

AIM: To study how products released from different bacteria in a deep carious lesion affect the metabolic activity of odontoblast-like cells and their ability to produce the major organic component of dentine, collagen 1. METHODOLOGY: MDPC-23 cells were exposed to supernatants from biofilm cultures of strains isolated from the deepest part of a carious lesion as well as from a clinical isolate of Enterococcus faecalis. Lipoteichoic acid (LTA) and lipopolysaccharide (LPS) were used for comparison. Cell activity was assessed using an methyl-thiazolyl-diphenyl tetrazolium bromide (MTT) assay, and collagen 1 levels were determined by ELISA. RESULTS:The lesion microflora was dominated by Lactobacillus spp. Neither extracellular products from the isolates nor LPS affected the activity of the MDPC-23 cells, whereas extracellular products from E. faecalis and LTA significantly reduced total cell activity (P < 0.01). Enterococcus faecalis had an inhibitory effect upon collagen 1 production by the cells, whereas no such effect or even a slight stimulatory effect was seen for the isolates from the deep carious lesion. CONCLUSIONS: These studies indicate that culture supernatants from E. faecalis reduced the metabolic activity of odontoblast-like cells as shown using the MTT assay. No effect was seen for supernatants from biofilms of bacteria recovered from a deep carious lesion. Different bacteria varied in their effects upon collagen 1 production suggesting that the nature of the bacterial species in a carious lesion may have a direct influence upon the ability of the odontoblasts to produce tertiary dentine.

The aim was to update a systematic review of pulp capping and partial pulpotomy by Olsson et al. (2006), by evaluating new evidence on formation of a hard tissue barrier after pulp capping and partial pulpotomy of experimental exposures in humans. PubMed (01-01-2005 to 01-03-2014) and CENTRAL were searched using specific keywords. Hand searches were made and the level of evidence for each included article was evaluated by the authors. The evidence of the conclusions was graded as strong, moderately strong, limited or insufficient. The initial search in PubMed yielded 215 abstracts. Hand searches of reference lists yielded no additional original scientific articles. After a selection process and interpretation, 22 articles were included and rated for level of evidence: no article was rated as high and seven as moderate. Overall the methodological quality of studies has improved since the previous systematic review was published in 2006. The conclusions are that there is limited scientific evidence that application of calcium hydroxide or mineral trioxide aggregate to an exposed pulp frequently results in formation of a hard tissue barrier, whereas adhesives or enamel matrix derivatives do not. There is insufficient scientific evidence that mineral trioxide aggregate promotes hard tissue formation more frequently than calcium hydroxide.

Background: There is limited and conflicting data on the reduction of circulatory inflammatory mediators in patients with apical periodontitis (AP) following endodontic treatment.

Objective: To answer the following research question: in adult healthy patients with AP [Population (P)], is there a difference before [Comparator (C)] and after various endodontic treatments (nonsurgical, surgical or retreatment) [Intervention (I)] on systemic levels of inflammatory biomarkers [Outcome (O)] in the follow-up period [Time (T)]?

Methods: An electronic literature search was conducted in the databases Scopus, PubMed, Clarivate Analytics' Web of Science, Cochrane Database of Systematic Reviews and Grey literature from inception to July 2024 with no language restrictions. Observational studies examining changes in serum levels of inflammatory mediators were included. Two independent reviewers selected studies, extracted data and critically appraised the included studies. Qualitative and quantitative (meta-analysis) data synthesis methods were employed. The Newcastle-Ottawa Scale was used to assess the quality of the included studies.

Results: Sixteen studies met the inclusion criteria, of which six were included in the meta-analysis. These studies were published between 1992 and 2024, involving a total of 596 patients (54% females) aged between 16 and 75 years. The meta-analysis of pooled data showed a significant decrease in high-sensitive C-reactive protein (hs-CRP) levels in the serum of patients with AP 6 months after treatment [2.26 ± 1.76 versus 1.28 ± 1.06 mg/L, (Z = 2.03, p = .04)] and a decrease in interleukin-1β (IL-1β) levels 12 months after treatment [13.01 ± 5.95 versus 10.86 ± 3.52 pg/mL, (Z = 3.72, p < .01)]. One study was assessed as poor quality, while all others were considered high quality.

Discussion: Despite the differences in methodologies across the included studies, it has been established that effective endodontic treatment leads to a reduction in systemic inflammatory biomarkers in the body.

Conclusion: Following effective endodontic treatment in patients with AP, the systemic levels of hs-CRP and IL-1β exhibit a significant reduction at 6 and 12 months, respectively. Further clinical studies should investigate whether effective endodontic treatment and reduced levels of investigated biomarkers may change the clinical presentation of systemic diseases.

BACKGROUND: The exposed pulp has been the topic of numerous studies, but well-designed and well-executed comparative trials on the outcome and treatment of these teeth have been limited.

OBJECTIVES: This study was conducted to answer the following questions: in patients with nontraumatic pulpitis associated with no or nonspontaneous pain in permanent teeth, (i) is direct pulp capping or pulpotomy (partial/full) as effective as selective or stepwise caries removal [Population/participants, Intervention(s), Comparator(s)/control, Outcome(s) (PICO) 1], (ii) is pulpotomy (partial/full) as effective as direct pulp capping (PICO 2) and (iii) is pulpotomy (partial/full) as effective as a pulpectomy (PICO 3), in terms of a combination of patient and clinical reported outcomes, with 'tooth survival' as the most critical outcome?

METHODS: A literature search was conducted using Clarivate Analytics' Web of Science, Scopus, PubMed and Cochrane Central Register of Controlled Trials from inception to November 3rd 2021. Grey literature and contents of the major subject journals were examined. Eligibility criteria followed the PICO questions. Two independent reviewers performed study selection, data extraction and appraisal; disagreements were resolved by a third reviewer. The risk of bias was assessed by the revised Cochrane risk-of-bias tool for randomized trials.

RESULTS: Three randomized clinical trials (RCTs) were included in the review. No study fulfilled the criteria to answer PICO 1. There were no significant differences in the reported outcomes between investigated treatments in all included RCTs. None of the included studies reported the most critical outcome 'tooth survival'. A high loss of patients during the follow-up period was observed.

DISCUSSION: Although a few studies fulfilled strict eligible criteria, the results of this systematic review clearly highlight a paucity of available evidence. At the present time, clinical decisions cannot be substantiated by direct comparative trials.

CONCLUSIONS: Based on limited evidence, this systematic review discovered no significant differences in effectiveness between compared vital pulp treatments in managing nontraumatic pulpitis associated with no or nonspontaneous pain. Further high-quality RCTs are necessary to investigate the effectiveness of direct pulp capping or pulpotomy (partial/full) compared to selective or stepwise caries removal.

REGISTRATION: PROSPERO database (CRD42021259742).

AIM: To (1) investigate the frequency and characteristics of pain and discomfort associated with root filled teeth in adult patients regularly attending the Public Dental Service in Örebro County, Sweden; (2) assess the association between symptoms and clinical and radiographic findings, and (3) explore the impact of pain and discomfort from root filled teeth on daily life. METHODOLOGY: Patient records of adult patients (> 20 years) scheduled for routine check-ups in April 2015 were screened to identify individuals with root filled teeth; all patients with >1 root filled tooth were asked to participate. The examination comprised clinical and radiographic examinations and questionnaires on general health, on pain symptoms from root filled teeth, and on the impact of pain on daily activities. In a general estimation equation (GEE), examination findings and patient-related factors were independently analysed in relation to the outcome "presence of pain". RESULTS: In total 550 patients with 1 256 root filled teeth participated. Fifty-three patients (9.6%) experienced pain or discomfort from 62 (4.9%) root filled teeth. Lower age, percussion tenderness and apical tenderness were significantly associated with pain (P > 0.001-P=0.044). The average pain intensity was 2.1 on (0-10) Numeric Rating Scale, and average duration was 28.4 months. The impact on daily life was low. CONCLUSIONS: On average, pain associated with root filled teeth was of mild intensity, >2 years of duration and had low impact on daily life. Although the significantly associated clinical findings may indicate apical periodontitis as the most probable explanation in some teeth, the origin of pain from root filled teeth remains partly unexplained.

Aim The aim was to examine the prevalence and characteristics of pain and discomfort from root-filled teeth in an adult Swedish population regularly attending dental care. A further aim was to examine if symptoms could be related to (i) periapical radiographic appearance and (ii) clinical findings. Methodology This cross-sectional observational study screened all adult patients scheduled for routine check-up in the public dental service, Örebro County, Sweden in April 2015. All (798) individuals with at least one root-filled tooth were asked to participate. The examination included (i) clinical examination, (ii) radiographic examination (intraoral periapical images), (iii) interviewer-assisted questionnaire covering general health and presence and characteristics of pain. Descriptive statistics were performed and Fisher’s exact test analysed correlations. Results 549 patients with 1256 root-filled teeth participated (292 women, 257 men; mean age 61.1 years, range 20–94). 55 (10.0%) of the patients experienced pain or discomfort from at least one root-filled tooth. On tooth level, 66 (5.3%) of all root-filled teeth were symptomatic. The average pain intensity was 2.2±1.9 on a 0–10 Numeric Rating Scale, and mean pain duration was 32.6 months. The pain was continuous for 21.3%, recurrent for 44.3%, and occasional for 34.4% of the teeth, and the teeth had been painful on average 9.6 of the last 30 days. Apical radiolucency was recorded at 264 (21.6%) of the root-filled teeth. Symptoms were significantly associated with presence of radiolucency (P=0.004), sinus tract (P=0.023), and pocket depth >5mm (P=0.038). Conclusions In the examined population, one in ten adults with a root-filled tooth experienced pain or discomfort associated with this tooth. The pain was generally of low intensity and long lasting. In most cases, the patient experienced recurrent or occasional pain, but one in five with painful teeth had continuous pain.

AIM: To evaluate the 10-year survival rate of root filled teeth treated by general dental practitioners (GDPs), and to identify possible prognostic factors.

METHODOLOGY: In 2006, 3 676 individuals had at least one tooth root filled by a GDP within the Norrbotten Public Dental Service, Sweden. Over the next 10 years, 331 individuals died and were excluded. A random sample of 302 of the remaining individuals were included in the study, of whom 280 (n=280 teeth) were included in the analysis. Dental records were reviewed retrospectively by a calibrated researcher to collect predetermined data regarding individual, preoperative, intra-operative, and postoperative factors. The outcome measure was tooth extraction over time, and cases with no events were censored, regardless of apical status or symptoms, until last known date of tooth survival. In case of missing data, individuals were recalled for a control visit. Kaplan-Meier survival tables, and Cox regression models were used for analysis. P<0.05 was considered statistically significant.

RESULTS: The cumulative 10-year survival was 81.7% (standard error: 2.6%), and the mean incidence of tooth extraction during the 10 years was 1.8% per year. The univariate analysis identified three possible prognostic factors (p<0.05) that were associated with extraction: molars, two or more emergency inter-appointment visits during the treatment, and root canal treatments consisting of five or more separate sessions. A multivariate regression analysis revealed no significant relationships for the variables gender, tooth type, number of contacts, any emergency visits during endodontic treatment, number of sessions to complete endodontic treatment, pulp diagnosis, or type of permanent restoration and extraction.

CONCLUSIONS: The mean incidence of tooth loss over the first 10 years after completion of root canal treatment performed by a GDP was approximately 2% per year. No prognostic factors could be identified.

OBJECTIVES: To survey the clinical endodontic protocols of general dental practitioners (GDPs) in public dental clinics and to assess the effect of an educational intervention on the adoption of a nickel-titanium (Ni-Ti) rotary system. METHODS: General dental practitioners in a Swedish Intervention County (IC), underwent an educational programme in endodontics. A follow-up questionnaire was posted to 98 GDPs in the IC and to 97 GDPs in a Control County (CC), where no specific training had been provided. The questionnaire concerned demographics, clinical endodontic protocols and instrumentation techniques. RESULTS: The response rate to the questionnaire was 87%. More than 90% of all GDPs reported they always or generally used rubber dam, determined working length, used the canal irrigant 0.5% buffered NaOCl and calcium hydroxide as an interappointment dressing. Two of three GDPs reported, they generally or always informed the patient of the prognosis. Every second GDP reported routines for postoperative recall and follow-up. The Ni-Ti rotary technique was reported to be completely adopted by 77% of the GDPs in the IC, significantly higher than in the CC (6%), P < 0.001. In the IC 79% of the GDPs reported they completed instrumentation in one treatment session, compared with only 32% in the CC, P < 0.001. The 'single-cone' mode of canal filling was reported to be significantly more frequent amongst GDPs in the IC, P < 0.001. CONCLUSIONS: General dental practitioners in both counties reported using contemporary clinical endodontic protocols. GDPs who had undergone an educational programme in Ni-Ti rotary instrumentation reported they had successfully integrated the technique into daily clinical practice.

AIM: To compare root canal treatments performed before and after education in a nickel-titanium rotary technique (NiTiR) with respect to costs for instrumentation and number of instrumentation sessions in a County Public Dental Service in Sweden. METHODOLOGY: Following education, 77% of the general dental practitioners adopted completely the NiTiR. The randomly selected sample comprised 850 root canal treatments: 425 performed after the education, mainly using the NiTiR-technique (group A) and 425 performed before, using mainly stainless steel hand instrumentation (SSI) (group B). The number of instrumentation sessions in root canal treatments in group A and B was calculated. A CMA was undertaken on the assumption that treatment outcome was identical in group A and B. Direct costs associated with SSI and NiTiR were estimated and compared. Investment costs required for implementation of NiTiR were calculated, but not included in the CMA. RESULTS: Instrumentation sessions were counted in 418 (98%) root canal treatments performed in group A and 419 (99%) in group B. The number of instrumentation sessions in group A was significantly lower; 2.38, compared with 2.82 in group B (P < 0.001). Thus, on average, for every second root canal treatment performed after the education, one instrumentation session was saved. Root canal treatments in teeth with one canal, and three or more canals, were completed in significantly fewer instrumentation sessions after the education (P < 0.001). Direct costs of instrumentation sessions were SEK 2587 (USD 411) for group A and SEK 2851 (USD 453) for group B, for teeth with one canal, and SEK 2946 (USD 468) for group A and SEK 3510 (USD 558) for group B, for teeth with three or more canals (year 2011). Root canal treatments of teeth with two canals showed no significant difference with respect to number of instrumentation sessions and costs. CONCLUSIONS: Significantly fewer instrumentation sessions were required in group A, and root canal instrumentation therefore costs less than in group B. On the assumption that treatment outcome is identical in group A and B, root canal instrumentation performed after the education was more cost-effective.

Aim To compare the technical quality and long-term outcomes of root canal treatment by general practitioners of a Swedish Public Dental Service, before and after an endodontic education including Ni-Ti rotary technique (NiTiR). Methodology A random sample was compiled, comprising one root filled tooth from each of 830 patients, treated by 69 general practitioners participating in the education: 414 teeth root filled in 2002, pre-education, using primarily stainless steel instrumentation and filling by lateral compaction, and 416 teeth root filled post-education (2005), using mainly NiTiR and single-cone obturation. Follow-up radiographs taken in 2009 were evaluated alongside immediate post-filling radiographs from 2002 to 2005. The density and length of the root fillings were registered. Periapical status was assessed by the Periapical Index (PAI), using two definitions of disease: apical periodontitis (AP) (PAI 3 + 4 + 5) and definite AP (PAI 4 + 5). Tooth survival was registered. Root fillings pre- and post-education were compared using chi-square and Fisher's exact tests. Crude extraction rates per 100 years were calculated for comparison of tooth survival. Explanatory variables (type of tooth, root filling quality, periapical status, marginal bone loss, type and quality of coronal restoration) in relation to the dependent variable (AP at follow-up) were analysed by multivariable logistic regression. Results Follow-up data were available for 229 (55%) of teeth treated pre-and 288 (69%) treated post-education: both tooth survival (P < 0.001) and root filling quality were significantly higher (P < 0.001) in the latter. However, there was no corresponding improvement in periapical status. Both preand post-education, root fillings with definite AP on completion of treatment had significantly higher odds of AP or definite AP at follow-up. For teeth treated post-education, inadequate root filling quality was significantly associated with AP at follow-up. Conclusions Despite a higher tooth survival rate and a significant improvement in technical quality of root fillings after the education, there was no corresponding improvement in periapical status.

AIM: To study the demographics of Swedish adults who had received a root filling, followed by extraction during the following 5-6 years in comparison with subjects who had undergone a corresponding root filling with an uneventful outcome. METHODOLOGY: The root filled maxillary first molar was chosen as the comparison model. The Swedish Social Insurance Agency provided data on all teeth reported as root filled in Sweden during 2009. A comparison group, equally large as the study group, was constructed by randomly selecting subjects with root filled maxillary first molars, which had not subsequently been extracted, that is, an uneventful outcome. Demographic data on the subjects were obtained from Statistics Sweden: country of birth, disposable income, educational level, age, civil status and gender. Chi-square, t-tests and logistic regression were used for statistical analyses. RESULTS: In the year 2009, 36 139 maxillary first molar teeth were reported to have been root filled, 4362 (12.1%) of which were then recorded as extracted during the following 5-6 year period. Only minor intergroup differences were noted: 86.5% of the study group were Swedish-born, compared with 84.4% of the comparison group (P = 0.007). Women comprised 53.2% of the study group and 50.5% (P = 0.01) of the comparison group. There was an association between extractions and gender as well as age; men had a lower odds ratio (OR) for extraction OR, 0.87; confidence interval (CI), 0.80-0.95. For every additional year, the chance for extraction was higher OR, 1.01; CI, 1.01-1.01. No other significant differences were detected. CONCLUSIONS: There was only little or no demographic differences between the study group, comprising Swedish adults who had undergone root filling of one of their maxillary first molars in 2009 and subsequent extraction during the following 5-6 years, and the comparison group, with uneventful outcomes after a corresponding root filling.

Aim: To explore the context in which general dental practitioners (GDPs) decide to refrain from further treatment, that is, ortho- or retrograde retreatment or extraction of a root canal filled tooth with persistent asymptomatic apical periodontitis (PAAP).

Methodology: Fifteen GDPs were strategically selected for in-depth interviews. The informants were encouraged to describe in their own words and in as much detail as possible, the three most recent patient cases of PAAP of a root canal filled tooth, in which they decided to refrain from further treatment. The interviews were recorded digitally and transcribed verbatim. The collected material was analysed according to Qualitative Content Analysis with an inductive approach.

Results: A pattern of varying degrees of uncertainty associated with the decision process was identified. The motives to refrain intervention had great diversity. The result from analysis of the qualitative data was formulated in an overall theme 'Between doubt and certainty in a complex clinical context' covering the latent content. The first main category covering the manifest content was 'The continuum of confidence' with three subcategories 'Experienced uncertainty', 'Reluctant approval' and 'At ease with refraining' illustrating the feelings and attitudes experienced by the informants. The second category was 'In support of acceptance' with three subcategories 'Patient's autonomy, risks and cost-benefits', 'Emotional aspects' and 'Relieving measures' representing the reasons for refraining from intervention.

Conclusions: The decision to refrain from further treatment, that is, ortho- or retrograde retreatment or extraction of a root canal filled tooth with PAAP was made with some measure of confidence, combined with compensatory strategies to support the decision, taking into account not only values beneficial to the patient and awareness of limited external resources, but also factors related to the informants' personal preferences, convenience, concerns, ambition and emotions.

AIM: To investigate the 5-year frequency of additional treatments in relation to the number of reported root filled canals in molar teeth in Sweden.

METHODOLOGY: The cohort included first and second molars in adult individuals who were registered with a root filling performed in 2009. Treatment codes corresponding to root fillings of teeth with from one up to four root filled canals were identified in the Swedish Social Insurance Agency database. The studied additional treatments were extraction, non-surgical root canal retreatment and endodontic surgery during the subsequent 5 years, identified by corresponding codes for these treatments registered on these specific teeth. Differences in the frequency of additional treatments based on the number of root filled canals were analysed using Chi-square test, and considered statistically significant at p<0.05.

RESULTS: In 2009, root fillings on a first or second molar tooth were registered in 100 720 individuals. The study included 32 901 maxillary first molars (6.4% with four root filled canals), 12 763 maxillary second molars (3.3% with four root filled canals), 37 703 mandibular first molars (19.2% with four root filled canals) and 17 353 mandibular second molars (3.7% with four root filled canals). The total frequency additional treatments was 14.3% (n=14 425) during the 5-year observational period. Additional treatments were more frequent in teeth with 1-3 root filled canals compared to teeth with four root filled canals for maxillary first molars (15.2% vs. 12.7%, p=0.002), maxillary second molars (13.8% vs. 9.1%, p=0.007) and mandibular first molars (14.0% vs. 10.7%, p<0.001) but not mandibular second molars (15.6% vs. 13.7%, p=0.200).

CONCLUSIONS: Over 5 years, 85.7% of the included teeth were not registered with any additional treatments. Maxillary first and second molars and mandibular first molar teeth had a greater frequency of additional treatments when ≤3 root canals were root filled compared to 4 canals.

The aim of this systematic review was to appraise the diagnostic accuracy of signs/symptoms and tests used to determine the condition of the pulp in teeth affected by deep caries, trauma or other types of injury. Radiographic methods were not included. The electronic literature search included the databases PubMed,EMBASE, The Cochrane Central Register of Controlled Trials and Cochrane Reviews from January 1950 to June 2011. The complete search strategy is given in an Appendix S1 (available online as Supporting Information. In addition, hand searches were made. Two reviewers independently assessed abstracts and full-text articles. An article was read in full text if at least one of the two reviewers considered an abstract to be potentially relevant. Altogether, 155 articles were read in full text. Of these, 18 studies fulfilled pre-specified inclusion criteria. The quality of included articles was assessed using the QUADAS tool. Based on studies of high or moderate quality, the quality of evidence of each diagnostic method/test was rated in four levels according to GRADE. No study reached high quality; two were of moderate quality. The overall evidence was insufficient to assess the value of toothache or abnormal reaction to heat/cold stimulation for determining the pulp condition. The same applies to methods for establishing pulp status, including electric or thermal pulp testing, or methods for measuring pulpal blood circulation. In general, there are major shortcomings in the design, conduct and reporting of studies in this domain of dental research.

Aim To demonstrate how the spectrum of diseased pulps may influence sensitivity and specificity in diagnostic studies on pulp status. Methodology An original sample from a previous study consisting of 59 teeth scheduled for root canal treatment was used where the relationship between the response to electric pulp testing and the visual status of the pulp was evaluated. To alter the spectrum of diseased pulps, a hypothetical sample of asymptomatic teeth with deep caries lesions was added to the original sample. Sensitivity and specificity were then compared for the two samples. Results In the original sample of 59 teeth, sensitivity was 72% and specificity 90%. When the spectrum of diseased pulps was altered, sensitivity decreased to 67% and specificity increased to 97%. The change in disease spectrum also decreased the prevalence of necrotic pulps. Conclusions The spectrum of diseased pulps included in a diagnostic study on the accuracy of electric pulp testing, and indirectly also disease prevalence (here pulp necrosis), influences estimates of sensitivity and specificity. This implies that estimates of diagnostic accuracy from one study with a particular tooth population spectrum may not apply to another tooth population with a different disease spectrum.

Aim: This historical prospective cohort study of the adult population of Sweden is based on data from a national registry: the primary aim was to evaluate the long-term survival of teeth after periradicular surgery. A secondary aim was to identify factors predictive of extraction within 10 years of registration of periradicular surgery.

Methodology: The cohort consisted of all individuals who had undergone periradicular surgery to treat apical periodontitis, as reported to the Swedish Social Insurance Agency (SSIA) during 2009. The cohort was followed until December 31, 2020. Subsequent registrations of extractions were collected for Kaplan-Meier survival analyses and survival tables. The patients' sex, age, dental service provider and tooth group were also retrieved from SSIA. Only one tooth per individual was included in the analyses. Multivariable regression analysis was used and P < 0.05 was considered statistically significant. The reporting guidelines STROBE and PROBE were followed.

Results: After data cleaning, and exclusion of 157 teeth, 5 622 teeth/individuals remained for analysis. The mean age of the individuals at the time of the periradicular surgery was 60.5 years (range 20-97, standard deviation 13.31); 55% were women. At the end of the follow-up, that is, up to 12 years, a total of 34.1% of the teeth had been reported as extracted. The multivariate logistic regression analysis, based on follow-up data at 10 years after registration of the periradicular surgery, included 5 548 teeth, of which 1 461 (26.3%) had been extracted. Significant associations between the independent variables tooth group and dental care setting (both P < 0.001) and the dependent variable extraction were found. The highest odds ratio (OR) for extraction applied to tooth group: compared to maxillary incisors and canines, mandibular molars were at greatest risk of extraction (OR 2.429, confidence interval 1.975-2.987, P < 0.001).

Conclusions: After periradicular surgery in predominantly elderly people in Sweden, approximately three quarters of the teeth are retained over a 10-year period. The type of tooth is associated with extraction: mandibular molars are at greater risk of extraction than maxillary incisors and canines.

Aim: To study the circumstances preceding the CBCT examination referral for endodontic reasons in Sweden. Methodology: Fourteen dentists (8 female) 33–58 years of age (mean =44), practicing in Sweden were strategically selected. Ten of the dentists were specialists in endodontics. The absolute inclusion criterion was experience of referring patients for CBCT for endodontic reasons. The included dentists provided a variation concerning gender, age, work experience, education background, location of practice, service affiliation and accessibility to CBCT. Data was obtained through thematic, semi-structured interviews exposing the context of their last self-reported three referrals. Dentists were encouraged to describe their experiences of the circumstances in their own words, aided by the interviewer’s openended questions. The interviews were audio recorded and transcribed verbatim. Qualitative content analysis was used to analyze the text. Results: The preliminary results may indicate that high clinical diagnostic standards, clinical common sense and a willingness of helping the patient with minimal harm may restrict the use of CBCT to address complex diagnostic judgements or therapeutic decisions, which comply with existing European guidelines on the use of CBCT in endodontics. Knowledge of guidelines was however limited among the interviewed dentists. Conclusions: Common sense and high professional standards seem to lead dentists in Sweden to comply with current European guidelines for the use of CBCT in endodontics even when the den tists lack knowledge of the guidelines. Acknowledgements: This work is funded by the Norrbotten County Council.

Aim: To gain insight into the decision processes of dentists when requesting a cone beam computed tomography (CBCT) examination in endodontic settings. Methodology: Fourteen dentists (eight female) 33–58 years of age (mean = 44) practising in Sweden were interviewed. Ten of the dentists were specialists in Endodontics. The absolute inclusion criterion was experience of referring patients for CBCT for endodontic reasons. The included dentists comprised a strategically selected diverse sample in terms of gender, age, work experience, educational background, location of practice, service affiliation and accessibility to CBCT. Data were obtained through semistructured interviews exposing the context of their last three self‐reported referrals. Dentists were encouraged to describe their experiences of the circumstances in their own words, aided by the interviewer's open‐ended questions. The interviews were audio‐recorded and transcribed verbatim. The text was analysed by qualitative content analysis. Results: The manifest content was organized into three categories that were defined as visualization as a desire, facilitating tough decisions and allocating responsibility. Conclusion: An overall theme (covering the latent content) was identified: A balance between clinical common sense and a ‘better safe than sorry’ attitude guides the use of CBCT in endodontic settings. Informants had high clinical standards, knowledge concerning radiation risks and good sense, which could compensate for their lack of knowledge of guidelines. The national radiation regulatory system was perceived to work as a slightly porous gatekeeper for over‐usage.

Aim To determine if Cone Beam Computed Tomography (CBCT) used in accordance with the European Commission guidelines has an impact on the diagnostic thinking confidence and therapeutic decision confidence in a population referred for endodontic problems. Methodology The study includes data collected from October 2011 until December 2012. From two different endodontic clinics consecutive patients were referred to a CBCT examination using criteria in accordance with the European Commission guidelines. The CBCT examinations were performed with similar equipment and standardized between clinics. After a thorough clinical examination and before CBCT examination, the endodontist scored the confidence for both diagnosis and therapeutic decision on a 100 mm visual analogue scale (VAS). After the CBCT examination both diagnosis and therapy plan were revised by the same dentist and a new VAS-score of confidence was performed. The VAS-scores before and after the CBCT examination were plotted for all teeth. Before and after assessments were analyzed with paired samples t-test. Results Fifty-seven patients were referred for a CBCT examination, representing 4% of all patients examined by both endodontic clinics during the study period. Four patients were excluded from the analysis as the protocol was not followed. The final data included 53 patients, and 81 teeth. For all teeth the mean score for diagnostic confidence before CBCT examination was 63 mm (SD 30). After CBCT-examination, the mean of the changes in diagnostic confidence for each patient was 23 mm (SD 27) (P < 0.01). The mean therapeutic decision confidence score Before CBCT was 67 mm (SD 25). The mean of the changes in therapeutic decision confidence after CBCT was 22 mm (SD 28) P < 0.01. Conclusions CBCT examination used in accordance with the European Commission guidelines increased the clinician’s confidence in both diagnostic thinking and therapeutic decision in a population with endodontic problems.

AIM: To determine whether the outcome of cone beam computed tomography (CBCT) examinations performed in accordance with the European Commission guidelines in a clinical setting has an impact on choosing diagnoses in endodontics. METHODOLOGY: A prospective observational study was conducted. Fifty-three consecutive patients (81 teeth) from two different endodontic specialist clinics in Sweden were followed. After performing a thorough clinical examination (based on the history, clinical findings, and diagnostic tests such as intra-oral radiography), the examiner wrote down a preliminary diagnosis before CBCT examination. After the CBCT examination, a new diagnosis was made by the same examiner. Both the pre- and the post-CBCT examination diagnoses were plotted according to patients and teeth. The CBCT examinations were performed using similar equipment and protocols that were standardized amongst the clinics. RESULTS: The diagnoses were changed for at least one tooth in 22 patients (41%); overall, the diagnoses were changed for 28 teeth (35%). CONCLUSION: CBCT has a substantial impact on diagnostic thinking in endodontics when used in accordance with the European Commission guidelines.

Diagnostic accuracy studies play an important role in informing clinical practice and patient management, by evaluating the ability of diagnostic testing and imaging to identify the presence or absence of a disease or condition. These studies compare the relative diagnostic strength of the test or device with a reference standard, therefore, guiding clinical decisions on the reliability of the test, the need for further tests, and whether to monitor or treat a particular condition. Inadequate and incomplete reporting of diagnostic accuracy studies can disguise methodological deficiencies and ultimately result in study bias and the inability to translate research findings into daily clinical practice. The Preferred Reporting Items for Diagnostic Accuracy Studies in Endodontics (PRIDASE) guidelines are being developed in order to improve the accuracy, transparency, completeness and reproducibility of diagnostic accuracy studies in the speciality of Endodontology. The aim of this paper is to report the process used to develop the PRIDASE guidelines based on a well-established consensus process. The project leaders (PD, VN) formed a steering committee of nine members (PD, VN, PA, AF, DR, SP, CK, MP, HD) to oversee and manage the project. The PRIDASE steering committee will develop the initial draft of the PRIDASE guidelines by adapting and modifying the Standards for Reporting of Diagnostic Accuracy Studies (STARD) 2015 guidelines, adding new items related specifically to the nature of Endodontics and incorporate the Clinical and Laboratory Images in Publication (CLIP) principles. The initial guidelines will consist of a series of domains and individual items and will be validated by the members of a PRIDASE Delphi Group (PDG) consisting of a minimum of 30 individuals who will evaluate independently the individual items based on two parameters: 'clarity' using a dichotomous scoring (yes/no) and 'suitability' for inclusion using a 9-point Likert Scale. The scores awarded by each member and any suggestions for improvement will be shared with the PDG to inform an iterative process that will result in a series of items that are clear and suitable for inclusion in the new PRIDASE guidelines. Once the PDG has completed its work, the steering committee will create a PRIDASE Meeting Group (PMG) of 20 individuals from around the world. Members of the PDG will be eligible to be the part of PMG. The draft guidelines and flowchart approved by the PDG will then be presented for further validation and agreement by the PMG. As a result of these discussions, the PRIDASE guidelines will be finalized and then disseminated to relevant stakeholders through publications and via the Preferred Reporting Items for study Designs in Endodontology (PRIDE) website (http://pride-endodonticguidelines.org). Periodic updates to the PRIDASE guidelines will be made based on feedback from stakeholders and end-users.

September 2019 in Vienna, Austria. A total of 21 individuals from across the globe and four steering committee members (PD, VN, HD, LB) attended the meeting. As a consequence of the discussions, the guidelines were modified and then piloted by several authors whilst writing a manuscript. The PRIRATE 2020 guidelines contain a checklist consisting of 11 sections and 58 individual items as well as a flowchart, considered essential for authors to include when writing manuscripts for randomized clinical trials in Endodontics.

Observational studies have a significant role in establishing the prevalence and incidence of diseases in populations, as well as determining the benefits and risks associated with health-related interventions. Observational studies principally encompass cohort, case-control, case series and cross-sectional designs. Inadequate reporting of observational studies is likely to have a negative impact on decision-making in day-to-day clinical practice; however, no reporting guidelines have been published for observational studies in Endodontics. The aim of this project is to develop reporting guidelines for authors when creating manuscripts describing observational studies in the field of Endodontology in an attempt to improve the quality of publications. The new guidelines for observational studies will be named: 'Preferred Reporting items for OBservational studies in Endodontics (PROBE)'. A steering committee was formed by the project leaders (PD, VN) to develop the guidelines through a five-phase consensus process. The steering committee will review and adapt items from the STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) statement and the Clinical and Laboratory Images in Publications (CLIP) principles, as well as identify new items that add value to Endodontics. The steering committee will create a PROBE Delphi Group (PDG), consisting of 30 members across the globe to review and refine the draft checklist items and flowchart. The items will be assessed by the PDG on a nine-point Likert scale for relevance and inclusion. The agreed items will then be discussed by a PROBE Face-to-Face meeting group (PFMG) made up of 20 individuals to further refine the guidelines. After receiving feedback from the PFMG, the steering committee will pilot and finalize the guidelines. The approved PROBE guidelines will be disseminated through publication in relevant journals, and be presented at national and international conferences. The PROBE checklist and flowchart will be available and downloadable from the Preferred Reporting Items for study Designs in Endodontics (PRIDE) website: . The PROBE steering committee encourages clinicians, researchers, editors and peer reviewers to provide feedback on the PROBE guidelines to inform the steering group when the guidelines are updated.

Observational studies are non-interventional studies that establish the prevalence and incidence of conditions or diseases in populations or analyse the relationship between health status and other variables. They also facilitate the development of specific research questions for future randomized trials or to answer important scientific questions when trials are not possible to carry out. This article outlines the previously documented consensus-based approach by which the Preferred Reporting items for Observational studies in Endodontics (PROBE) 2023 guidelines were developed. A steering committee of nine members was formed, including the project leaders (PD, VN). The steering committee developed an initial checklist by combining and adapting items from the STrengthening the Reporting of Observational studies in Epidemiology (STROBE) checklist and the Clinical and Laboratory Images in Publications (CLIP) principles, as well as adding several new items specifically for the specialty of Endodontics. The steering committee then established a PROBE Delphi Group (PDG) and a PROBE Online Meeting Group (POMG) to obtain expert input and feedback on the preliminary draft checklist. The PDG members participated in an online Delphi process to reach consensus on the clarity and suitability of the items present in the PROBE checklist. The POMG then held detailed discussions on the PROBE checklist generated through the online Delphi process. This online meeting was held via the Zoom platform on 7th October 2022. Following this meeting, the steering committee revised the PROBE checklist, which was piloted by several authors when preparing a manuscript describing an observational study for publication. The PROBE 2023 checklist consists of 11 sections and 58 items. Authors are now encouraged to adopt the PROBE 2023 guidelines, which will improve the overall reporting quality of observational studies in Endodontics. The PROBE 2023 checklist is freely available and can be downloaded from the PRIDE website (https://pride-endodonticguidelines.org/probe/).

Observational studies play a critical role in evaluating the prevalence and incidence of conditions or diseases in populations as well as in defining the benefits and potential hazards of health-related interventions. There are currently no reporting guidelines for observational studies in the field of Endodontics. The Preferred Reporting Items for study Designs in Endodontology (PRIDE) team have developed and published new reporting guidelines for observational-based studies called the “Preferred Reporting items for OBservational studies in Endodontics (PROBE) 2023” guidelines. The PROBE 2023 guidelines were developed exclusively for the specialty of Endodontics by integrating and adapting the “STrengthening the Reporting of OBservational studies in Epidemiology (STROBE)” checklist and the “Clinical and Laboratory Images in Publications (CLIP)” principles. The recommendations of the Guidance for Developers of Health Research Reporting Guidelines were adhered to throughout the process of developing the guidelines. The purpose of this document is to serve as a guide for authors by providing an explanation for each of the items in the PROBE 2023 checklist along with relevant examples from the literature. The document also offers advice to authors on how they can address each item in their manuscript before submission to a journal. The PROBE 2023 checklist is freely accessible and downloadable from the Preferred Reporting Items for study Designs in Endodontology (PRIDE) website (http://pride-endodonticguidelines.org/probe/).

Studies investigating the accuracy of diagnostic tests should provide data on how effectively they identify or exclude disease in order to inform clinicians responsible for managing patients. This consensus-based project was undertaken to develop reporting guidelines for authors submitting manuscripts, which describe studies that have evaluated the accuracy of diagnostic tests in endodontics. These guidelines are known as the Preferred Reporting Items for Diagnostic Accuracy Studies in Endodontics (PRIDASE) 2024 guidelines. A nine-member steering committee created an initial checklist by integrating and modifying items from the Standards for Reporting of Diagnostic Accuracy (STARD) 2015 checklist and the Clinical and Laboratory Images in Publications (CLIP) principles, as well as adding a number of new items specific to the specialty of endodontics. Thereafter, the steering committee formed the PRIDASE Delphi Group (PDG) and the PRIDASE Online Meeting Group (POMG) in order to collect expert feedback on the preliminary draft checklist. Members of the Delphi group engaged in an online Delphi process to reach consensus on the clarity and suitability of the items in the checklist. The online meeting group then held an in-depth discussion on the online Delphi-generated items via the Zoom platform on 20 October 2023. According to the feedback obtained, the steering committee revised the PRIDASE checklist, which was then piloted by several authors when preparing manuscripts describing diagnostic accuracy studies in endodontics. Feedback from this process resulted in the final version of the PRIDASE 2024 checklist, which has 11 sections and 66 items. Authors are encouraged to use the PRIDASE 2024 guidelines when developing manuscripts on diagnostic accuracy in endodontics in order to improve the quality of reporting in this area. Editors of relevant journals will be invited to include these guidelines in their instructions to authors.

AIM: To investigate the effect of Emdogain Gel (Biora AB, Malmo, Sweden), consisting of a enamel matrix derivative (EMD) in a propylene glycol alginate (PGA) vehicle, on experimentally exposed human pulps and to register postoperative symptoms. METHODOLOGY: Nine pairs of contralateral premolars scheduled for extraction on orthodontic indications were included. Following a superficial pulp amputation performed with a small (016) diamond bur, either EMDgel or a mix of calcium hydroxide and sterile saline was placed at random in contact with the pulp wound. The subjects made records of symptoms and were also interviewed about pain/discomfort by a blinded examiner. After 12 weeks the teeth were extracted, prepared and subjected to light microscopic examination in which the inflammation and newly formed hard tissue in the pulp were analysed. Immunohistochemistry was performed using affinity-purified rabbit anti-EMD polyclonal antibodies. RESULTS: Postoperative symptoms were less frequent in the EMDgel-treated than in the calcium hydroxide-treated teeth, especially during the first six weeks. In the EMDgel-treated teeth, new tissue partly filled the space initially occupied by the gel and hard tissue was formed alongside the exposed dentine surfaces and in patches in the adjacent pulp tissue. EMD was detected in the areas where new hard tissue had been formed. The wound area of the EMDgel-treated teeth exhibited inflammation in the majority of the teeth whereas less inflammation was seen in the calcium hydroxide-treated teeth where the hard tissue was formed as a bridge. CONCLUSIONS: In the EMDgel-treated teeth, postoperative symptoms were less frequent and the amount and pattern of hard tissue formation were markedly different than in the teeth treated with calcium hydroxide. However, the operative procedure and the formulation with EMD in a PGA vehicle do not seem to be effective for the formation of a hard tissue barrier.

Aim To evaluate the evidence on the formation of a hard tissue barrier after pulp capping in humans. Methodology A PubMed and CENTRAL literature search with specific indexing terms and a hand search were made. The authors assessed the level of evidence of each publication as high, moderate or low. Based on this, the evidence grade of the conclusions was rated as strong, moderately strong, limited or insufficient. Results The initial search process resulted in a total of 171 publications. After reading the abstracts and hand searching the reference lists of the retrieved publications, 107 studies were retrieved in full-text and interpreted. After the interpretation, 21 studies remained and were included in the systematic review and given a level of evidence. No study had a high level of evidence, one study had moderate and 20 studies had a low level of evidence. There was heterogeneity between the studies; therefore, no meta-analysis was performed. The majority of studies on pulp capping using calcium hydroxide based materials reported formation of hard tissue bridging, studies on other pulp capping materials such as bonding agents presented inferior results. The evidence grade was insufficient. Conclusions Insufficient evidence grade does not necessarily imply that there is no effect of a pulp capping procedure or that it should not be used. Rather, the insufficient evidence underpins the need for high-quality studies.

AIM: Prior to certain medical therapies, dental assessment and treatment of oral foci of infection are recommended. The aim of the present study was to acquire a deeper understanding of the decision-making process regarding pre-medical management of root canal-filled teeth with asymptomatic apical periodontitis.

METHODOLOGY: Hospital-affiliated dentists in Sweden were contacted for a semi-structured, in-depth interview. The absolute inclusion criterion was that the dentists had experienced and could recount at least two authentic cases involving root canal-filled teeth with asymptomatic apical periodontitis - one case having resulted in pre-medical treatment, and one having resulted in expectancy. Fourteen interviews, with fourteen informants, were conducted and included in the study. During the interviews, open-ended questions and comments encouraging the informants to elaborate and clarify their experiences were offered. The interviews were digitally recorded, transcribed verbatim and analyzed using Qualitative Content Analysis with an inductive approach.

RESULTS: A theme describing the latent content was identified through interpretation of the collected data: A multifaceted balancing act characterized by a sometimes-difficult risk-benefit-estimation, where an increased uncertainty entails an increased reliance on external opinions. Three main categories, comprising four subcategories, describing the manifest content were recognized: The tipping scale, The team effort and The frame of reference.

CONCLUSION: The current interview study found pre-medical decision-making regarding root canal-filled teeth with asymptomatic apical periodontitis to be a multifactorial and contextual process marked by uncertainty and collaborative measures. Further research, resulting in the development of evidence-based treatment guidelines, is suggested necessary.

Aim: To investigate what happens to cross-sectionally identified root-filled teeth over a 6-year period, regardless of the time that elapsed since primary root canal treatment, in a cohort of adult patients regularly attending a Public Dental Service. A secondary aim was to investigate how the cumulative events affecting root-filled teeth over the same time were associated with variables obtained from a baseline examination.

Methodology: Adult patients with ≥1 previously root-filled tooth and regularly attending the Public Dental Service in Örebro County were enrolled for study participation in 2015. General dental practitioners examined all identified root-filled teeth in this cohort at baseline using a standardized protocol and were also responsible for further decision-making and treatments. After six years, information on events of the root-filled teeth was collected from dental records. The highest rating (most invasive treatment) on a 5-point ordinal scale was used in the analyses. Regression analyses with stepwise selection were performed for associations between patient- and tooth-related factors and events.

Results: A total of 445 patients with 1007 root-filled teeth were followed the entire observation time. Twenty (2.0%) of the root-filled teeth had endodontic retreatment and 150 (14.9%) were extracted over six years. Among teeth with periapical radiolucency or pain, the majority did not undergo retreatment or extraction; however, the multivariate analysis demonstrated that retreatment or extraction was associated with baseline recordings of teeth with periapical radiolucency (p < .0001), tenderness to percussion (p < .0001), and poor coronal restoration (p < .0001).

Conclusions: This study corroborates the notion that in general dentistry, root-filled teeth with radiological signs of apical disease often remain untreated over time. Furthermore, it also reveals that root-filled teeth presenting with mild pain do not necessarily receive any intervention. However, teeth with baseline signs of apical periodontitis, pain, or inadequate coronal restoration were more likely to have received intervention during the six-year period.

Aim: To compare demographic characteristics between individuals choosing an indirect coronal restoration (crown, inlay/onlay) and individuals receiving other restorations after completion of a root filling. The hypothesis was that there are demographic differences for individuals who chose an indirect and those who chose another coronal restoration after root canal treatment. Methodology: This was a registry study of a cohort consisting of all root filled upper first molars that were reported to the tax-funded Swedish Social Insurance Agency (SSIA) during 2009. The root filled teeth were identified by tooth position 16 and 26, and by specific registry codes applied to root fillings. After registration of the root filling, any subsequent coronal restorations within two years was identified. The study group consisted of individuals registered with a root filling followed by an indirect coronal restoration and the control group was the remaining individuals with a root-filled tooth and a direct coronal restoration or no registration of any coronal restoration. Data on nationality, disposable income, educational level, civil status, age and gender were received from Statistics Sweden or SSIA. Chi-square test, t-test and logistic regression compared groups. P<0.05 was considered statistically significant. Results: 7 806 individuals (21.9%) received an indirect coronal restoration and 27 886 individuals (78.1%) comprised the control group. All demographic variables but gender and nationality differed significantly between groups A significantly larger proportion of individuals in the study group had higher education, higher disposable income, were older and were less likely to be living on their own. Conclusions: The identified demographic differences between individuals having their newly root filled teeth restored with an indirect restoration compared to those receiving other restorations indicate that the tax-funded Swedish dental insurance fails to provide dental care on equal terms for Swedish citizens.

This systematic review evaluates the diagnostic accuracy of radiographic methods employed to indicate presence/absence and changes over time of periapical bone lesions. Also investigated were the leads radiographic images may give about the nature of the process and the condition of the pulp in nonendodontically treated teeth. Electronic literature search included the databases PubMed, Embase and CENTRAL from January 1950 to June 2011. All languages were accepted provided there was an abstract in English. The MeSH terms were ‘Cone beam computed tomography (CBCT)’,‘Radiography, panoramic’, ‘Periapical diseases’, ‘Dental pulp diseases’, ‘Sensitivity and specificity’, ‘receiver operating characteristics (ROC) curve’, ‘Cadaver’, ‘Endodontics’ and ‘Radiography dental’. Two reviewers independently assessed abstracts and full text articles. An article was read in full text if at least one of the two reviewers considered an abstract to be potentially relevant. Altogether, 181 articles were read in full text. The GRADE approach was used to assess the quality of evidence of each radiographic method based on studies of high or moderate quality. Twenty-six studies fulfilled criteria set for inclusion. None was of high quality;11 were of moderate quality. There is insufficient evidence that the digital intraoral radiographic technique is diagnostically as accurate as the conventional film technique. The same applies to CBCT. No conclusions can be drawn regarding the accuracy of radiological examination in identifying various forms of periapical bone tissue changes or about the pulpal condition.

AIM: To study the 20-year survival rate and periapical status of root filled teeth in a Swedish population requiring high-cost dental care and to identify factors related to survival and normal periapical status at follow-up. METHODOLOGY: The study population comprised 104 patients selected from four local health insurance districts with treatment plans including radiographs submitted for approval for reimbursement from the Swedish National Dental Insurance in 1977. In 1998, a clinical and radiographic follow-up examination was conducted, to register the status of 449 teeth identified as root filled at baseline. Differences in tooth survival and periapical status at follow-up, with reference to periapical status and quality of root filling at baseline, were analysed by chi-square tests. Multiple regression analysis was used to describe tooth survival and normal periapical status at follow-up, with the explanatory baseline variables: tooth type, type of restoration, type of post, quality of root filling, periapical status, marginal bone loss and caries. Differences were considered significant at a 5% level. RESULTS: Two hundred and ninety (65%) of the root filled teeth survived at follow-up. Baseline variables associated with low odds for tooth survival were mandibular molar, maxillary premolar, prefabricated posts other than screw posts, severe marginal bone loss, caries and apical periodontitis (AP). Normal periapical status at follow-up was registered in 49% of the root filled teeth. Baseline variables associated with low odds for normal periapical status (high risk for AP) at follow-up were mandibular molar, maxillary premolar, AP, severe marginal bone loss and inadequate root filling quality. Of the root filled teeth with AP at baseline, 42% had been left untreated during the observation period, and at follow-up, the AP persisted in 57% of these teeth. CONCLUSIONS: After 20 years, 65% of the root filled teeth had survived and one-third remained with a sound periapical condition, without any further treatment. Almost half of the APs registered at baseline were left without treatment, and more than half of them persisted after 20 years.

In many clinical cases a dentist may feel certain when for example diagnosing, deciding on treatment, or assessing the prognosis - in other cases many dentists may feel a degree of doubt or uncertainty. This paper aims to explore the philosophical concept of uncertainty and its different dimensions, using the condition "persistent apical periodontitis associated with a previously root filled tooth" as an example. Acknowledging that uncertainty exists in any clinical situation can be perceived as uncomfortable, as some might regard it as a weakness. While some types of uncertainty met in dental practice can be addressed and reduced, there are other types which are inevitable and must be accepted. To make sound decisions, it is pertinent that the dentist reflects on and values the consequences of uncertainty. In this paper, a conceptual model is presented by which the dentist can identify the type of uncertainty in a clinical case, making it possible to decide on a strategy on how to manage the uncertainty and its possible consequences, with the aim to support the dentist's care for their patients. The understanding that uncertainty exists and the ability to acknowledge and be comfortable with it when making decisions should be addressed throughout our professional career, and thus ought to be developed during undergraduate education. Some suggestions on how teachers could target this are given in the paper.

Abstract AIM: To investigate whether the additional diagnostic yield of a cone-beam computed tomography (CBCT) examination over conventional radiographs in patients primarily suspected of having atypical odontalgia (AO) improves differentiation between AO and symptomatic apical periodontitis (SAP) in patients with severe chronic intraoral pain. METHODOLOGY: In this clinical study, 25 patients (mean age 54 ± 11 years, range 34-72) participated; 20 were diagnosed with AO and 5 with SAP. All patients were recruited from the clinics of the Faculty of Odontology, Malmö University. AO inclusion criteria were chronic pain (>6 months) in a region where a tooth had been endodontically or surgically treated, with no pathological cause detectable in clinical or radiologic examinations. SAP inclusion criteria were recurrent pain from a tooth diagnosed with apical periodontitis in clinical and radiographic examinations. Assessments comprised a self-report questionnaire on pain characteristics, a comprehensive clinical examination and a radiographic examination including panoramic and intraoral radiographs and CBCT images. The main outcome measure was periapical bone destruction. RESULTS: Sixty per cent of patients with AO had no periapical bone destructions detectable with any radiographic method. Overall, CBCT rendered 17% more periapical bone destructions than conventional radiography. Average pain intensity in patients with AO was 5.6 (± 1.8) on a 0-10 numerical rating scale, and average pain duration was 4.3 (± 5.2) years. CONCLUSION: Cone-beam computed tomography improves identification of patients without periapical bone destruction, which may facilitate differentiation between AO and SAP.

The Preferred Reporting Items for Diagnostic Accuracy Studies in Endodontics (PRIDASE) 2024 guidelines are based on the Standards for Reporting of Diagnostic Accuracy Studies (STARD) 2015 guidelines and the Clinical and Laboratory Images in Publications (CLIP) principles, with the addition of items specifically related to endodontics. The use of the PRIDASE 2024 guidelines by authors and their application by journals during the peer review process will reduce the possibility of bias and enhance the quality of future diagnostic accuracy studies. The PRIDASE 2024 guidelines consist of a checklist containing 11 domains and 66 individual items. The purpose of the current document is to provide an explanation for each item on the PRIDASE 2024 checklist, along with examples from the literature to help readers understand their importance and offer advice to those developing manuscripts. A link to the PRIDASE 2024 explanation and elaboration document is available on the Preferred Reporting Items for study Designs in Endodontology (PRIDE) website (https://pride-endodonticguidelines.org/pridase/) and on the International Endodontic Journal website (https://onlinelibrary.wiley.com/page/journal/13652591/homepage/pride-guidelines.htm).

Aim: To study the association between endodontic inflammatory disease and a first myocardial infarction (MI).

Methodology: The study comprised 805 patients with recent experience of a first MI, each gender, age and geographically matched with a control. Panoramic radiographs were available for 797 patients and 796 controls. Endodontic inflammatory disease was assessed radiographically. The sum of decayed, missing and filled teeth (DMFT) was calculated, and the number of root filled teeth and teeth with periapical lesions were recorded. The associated risk of a first MI was expressed as odds ratios (OR) with 95% confidence intervals (CI), unadjusted and adjusted for confounders (family history of cardiovascular disease, smoking habits, marital status, education and diabetes).

Results: Patients who had suffered a first MI had higher DMFT (mean 22.5 vs. 21.9, p = .013) and more missing teeth (mean 7.5 vs. 6.3; p < .0001) than the healthy controls. The number of missing teeth was associated with an increased risk of a first MI (adjusted OR 1.04; CI 1.02-1.06). Conversely, decay-free, filled teeth were associated with decreased risk (adjusted OR 0.98; CI 0.96-1.00). Analysis based on age disclosed the following variables to be associated with an increased risk of a first MI: number of decayed teeth (adjusted OR 1.18; CI 1.02-1.37, in patients <60 years), any primary periapical lesion (adjusted OR 1.57; CI 1.08-2.29, in patients <65 years) and the proportion of root filled teeth (adjusted OR 1.18; CI 1.03-1.36, in patients ≥65 years).

Conclusions: More missing teeth was independently associated with an increased risk of a first MI. In addition, endodontic inflammatory disease may contribute as an independent risk factor to cardiovascular disease since untreated caries, periapical lesions and root fillings, depending on age, were significantly associated with a first MI.

Aim: To explore associations between root filled teeth, primary and secondary apical periodontitis, and levels of inflammatory markers in blood from patients with a first myocardial infarction and matched controls.

Methodology: Between May 2010 and February 2014, 805 patients with a first myocardial infarction and 805 controls, matched for sex, age, and postal code area, were recruited to the multicentre case-control study PAROKRANK (periodontitis and its relation to coronary artery disease). All participants underwent a physical and oral examination, as well as blood sampling. Using panoramic radiography, root filled teeth, primary apical periodontitis, and secondary apical periodontitis were assessed by three independent observers. Blood samples were analysed with enzyme-linked immunosorbent assay method for the following inflammatory markers: interleukin-1β (IL-1β), IL-2, IL-6, IL-8, IL-12p70, tumour necrosis factor-α, and high-sensitivity C-reactive protein (hsCRP). Additionally, white blood cell count and plasma-fibrinogen were analysed. Associations between endodontic variables and the levels of inflammatory markers were statistically analysed with Mann-Whitney U-test and Spearman correlation, adjusted for confounding effects of baseline factors (sex, age, myocardial infarction, current smoking, diabetes, family history of cardiovascular disease, education, marital status, and periodontal disease).

Results: Mean age of the cohort was 62 years, and 81% were males. Root fillings were present in 8.4% of the 39 978 examined teeth and were associated with higher levels of hsCRP, fibrinogen, and leukocyte count, but lower levels of IL-2 and IL-12p70. After adjusting for confounders, root filled teeth remained associated with higher levels of fibrinogen, but lower levels of IL-1β, IL-2, IL-6, and IL-12p70. Primary apical periodontitis was found in 1.2% of non-root filled teeth and associated with higher levels of IL-8 (correlation 0.06, p = .025). Secondary apical periodontitis was found in 29.6% of root filled teeth but did not relate to the levels of any of the inflammatory markers.

Conclusions: This study supports the notion that inflammation at the periapex is more than a local process and that systemic influences cannot be disregarded. Whether the observed alterations in plasma levels of inflammatory markers have any dismal effects on systemic health is presently unknown but, considering the present results, in demand of further investigation.

AIM: To document satisfaction with root canal treatment procedures and outcomes among patients treated at Swedish public dental clinics.

METHOD: The original material comprised 243 patients who began root canal treatment (RCT) at 20 public dental clinics in the county of Västra Götaland, Sweden. One to three years later, 236 (97.1%) were posted a questionnaire of eight items, rating patient perceptions of RCT-completion, present pain intensity and satisfaction with the RCT. To evaluate the reliability of the original responses, the first 50 respondents were mailed a follow-up questionnaire. Both descriptive and analytical statistics were used to compare respondents and non-respondents and tooth groups.

RESULTS: One hundred and fifty-nine patients (67.4%) responded: 86 (54.1%) women and 73 (45.9%) men. The mean age 52.5 years, was higher than for non-respondents (P<0.001). A completed root filling was registered for the majority of the teeth (n = 112, 70.9%), but significantly fewer molars had been completed (n = 46, 59.7%, P = 0.02). Fifty percent (n = 59) of the patients reported current pain, mostly mild in intensity (n = 45, 38.1%). One hundred and twenty-three patients (80.9%) recalled experiencing pain during RCT. The highest satisfaction was registered for the item 'chewing ability' (mean = 1.6, SD = 1.9). The majority of patients (n = 114, 75.0%) stated that in retrospect they would still have chosen RCT. However, these patients belonged to the group which either registered the tooth as still present, or had not experienced much discomfort during or after RCT. Forty-four patients (88.0%) responded to the second questionnaire. The reliability of the responses was good. In summary, one to 3 years after beginning RCT at a public dental clinic, patient satisfaction was high, even though every fourth molar had been extracted or treatment had not been completed and half the patients reported persistent pain. The reliability of the patients' responses was considered to be good.

CONCLUSIONS: The results indicate a need for further clinical observational studies of RCTs undertaken in general dental practice, with special reference to patient-centred outcomes.