Purpose 

This study aimed to evaluate the mechanical properties of the different layers of multi-layered zirconia materials produced with different strategies for gaining translucency.

Materials and methods 

Sixty zirconia specimens were prepared in a bar shape from two different partially sintered multi-layered zirconia blanks (KATANA™ Multi-layered Zirconia HTML, Kuraray Noritake Dental, EU) and (IPS e.max® ZirCAD Prime, Ivoclar, USA). The specimens were distributed into two groups based on the material used (n=30) and further subdivided into three subgroups according to the different layers of zirconia blanks: translucent, transition, and dentin (n=10). All specimens were subjected to a static three-point flexural strength test. A one-way ANOVA and a T-test were performed to determine the significant differences among the groups. 

Results 

The different layers of ZirCAD Prime showed significant differences in flexural strength (p=0.001). In contrast, the different layers of KATANA™ HTML showed no significant differences (p=0.437). A T-test was conducted to compare the results from different layers within the same material. The results of the One-Way ANOVA test for the different groups of KATANA™ HTML demonstrated no difference between the groups (p=0.437). 

Conclusion 

Different compositions of different multi-layered zirconia materials result in various mechanical properties. Brand-specific differences are an essential consideration for dentists and dental technicians when using multi-layered zirconia. It is crucial to consider various factors such as type of restoration, positioning of the restoration in the disc (nesting), and restoration to be used anteriorly or posteriorly, and the desired esthetical requirements as the translucency are gained in different ways.   

Purpose

 To evaluate the impact of implant length on failure rates between short (<10 mm) and long (≥10 mm) dental implants.

Materials and methods

A search was undertaken in three electronic databases, complemented by manual search of some journals. Implant failure was the outcome evaluated, with the estimate of relative effect expressed in risk ratio (RR). Heterogeneity among studies was evaluated by I²statistic. Inverse variance method was used for random- or fixed-effects models. Quality assessment of the studies was performed, and a funnel plot was drawn. A meta-regression was performed in order to verify how the RR was associated with the follow-up time.

Results

The reviews included 353 publications. Altogether, there were 25,490 short implants and 159,435 long implants. Pairwise meta-analysis showed that short implants had a higher risk of failure than long implants (RR 2.437, p<0.001). The meta-regression observed that the follow-up time did not have any effect of the RR of failure between short and long implants. A sensitivity analysis plotting together only the studies with follow-up up until 7 years, resulted in an estimated increase of 0.6 in RR for every additional month of follow-up.

Conclusion

Short implants showed (< 10 mm) a 2.5 times higher risk of failure than long implants (≥ 10 mm). Implant failure is multifactorial and the implant length is only one of the many factors contributing to the loss of implant. A good treatment plan and the patient’s general health should be taken into account when planning for an implant treatment.

Keywords: dental implant, failure, implant length, systematic review, meta-analysis

The present review aimed to evaluate the impact of implant length on failure rates between short (<10 mm) and long (>= 10 mm) dental implants. An electronic search was undertaken in three databases, as well as a manual search of journals. Implant failure was the outcome evaluated. Meta-analysis was performed in addition to a meta-regression in order to verify how the risk ratio (RR) was associated with the follow-up time. The review included 353 publications. Altogether, there were 25,490 short and 159,435 long implants. Pairwise meta-analysis showed that short implants had a higher failure risk than long implants (RR 2.437, p < 0.001). There was a decrease in the probability of implant failure with longer implants when implants of different length groups were compared. A sensitivity analysis, which plotted together only studies with follow-up times of 7 years or less, resulted in an estimated increase of 0.6 in RR for every additional month of follow-up. In conclusion, short implants showed a 2.5 times higher risk of failure than long implants. Implant failure is multifactorial, and the implant length is only one of the many factors contributing to the loss of an implant. A good treatment plan and the patient's general health should be taken into account when planning for an implant treatment.

The aim of this present record-based retrospective study was to investigate the influence of the crown-implant ratio (CIR) and implant inclination in relation to the occlusal plane on the marginal bone loss (MBL) around dental implants supporting single crowns in the posterior region of the jaws. All the cases of implant-supported single crowns in the premolar and molar regions were initially considered for inclusion. Only implants not lost, with baseline radiographs taken within 12 months after implant placement and with a minimum of 36 months of radiological follow-up, were considered for the analysis of MBL. Univariate linear regression models were used to compare MBL over time between 12 clinical covariates, after which a linear mixed-effects model was built. After the exclusion of 49 cases, a total of 316 implant-supported single crowns in 234 patients were included. The results from the statistical models suggested that implant inclination and anatomical- and clinical CIR (the main related factors investigated in the study) were not statistically significantly related to MBL over time. Age (older people), tooth region (premolar), and bruxism (bruxers) had a statistically significant influence on MBL over time.

Objective To investigate in 10 orthodontic journals how many randomized controlled trials (RCTs) considered the Hawthorne effect, and if considered, to determine whether it was related to the patients or the therapists involved in the trial and, finally, to discuss the Hawthorne effect in an educational way. Materials and methods A search was performed on the Medline database, via PubMed, for publication type ‘randomized controlled trial’ published for each journal between 1 August 2007 and 31 July 2017. The American Journal of Orthodontics and Dentofacial Orthopedics, Angle Orthodontist, Australian Orthodontic Journal, Dental Press Journal of Orthodontics, European Journal of Orthodontics, Journal of Orthodontics, Journal of Orofacial Orthopedics, Korean Journal of Orthodontics, Orthodontics and Craniofacial Research and Progress in Orthodontics were assessed. Two independent reviewers extracted the data and identified whether the Hawthorne effect was considered or discussed in the articles and whether the Hawthorne effect was related to the behaviour of the patients, the therapists, or both. Results The initial search generated 502 possible trials. After applying the inclusion and exclusion criteria, 290 RCTs were included and assessed. The Hawthorne effect was considered or discussed in 10 of 290 RCTs (3.4%), and all were related to the patients’ and none to the therapists’ behaviour. Conclusions The Hawthorne effect reported in orthodontic RCTs was suboptimal. The researchers’ lack of knowledge about this phenomenon is evident, despite evidence that the Hawthorne effect may cause over-optimistic results or false-positive bias.

Objective: To analyse in 10 orthodontic journals how many randomized controlled trials (RCTs) performed 'single-', 'double-', 'triple-', or 'outcome assessors blinding' and to evaluate, from the number of RCTs that did not conduct blinding, how many could actually have achieved it. Material and methods: Randomized controlled trials published in 10 orthodontic journals between 1 September 2012 and 28 February 2018 were included. A search was performed in PubMed and conducted for publication type 'randomized controlled trial' for each journal. Two reviewers independently analysed each RCT and registered that blinding was performed and included which specific type. It was also evaluated whether misclassifications of blinding items occurred and whether it was possible to achieve blinding among the RCTs that did not perform blinding. Results: After applying the inclusion criteria, 203 RCTs were assessed, and 61.6 per cent of them had used blinding, with the main type being 'outcome assessors blinding' (40.4%) followed by 'single-blinding' (15.3%), 'double-blinding' (2.5%), and 'triple-blinding' (3.4%). In 38.4 per cent of the trials, no blinding was performed; however, 79.4 per cent of them could have achieved blinding. Fifteen RCTs (7.3%) misclassified the blinding in relation to single-, double-, or triple-blinding. Journals followed the CONSORT (AJODO, EJO, JO, OCR) published together significantly more RCTs that performed blinding than journals not following the CONSORT. Conclusions: Blinding of outcome assessors was the most frequent type, as orthodontic trials are often of intervention design and thereby difficult to mask for patients and trial staff. The misclassifications of blinding items may indicate suboptimal knowledge among researchers and peer-reviewers regarding the definitions for diverse blinding types.

Objective: To examine: (I) the current evidence of the impact of fixed orthodontic appliances on the development of halitosis in patients undergoing orthodontic treatment, and (II) the influence of different orthodontic bracket systems on halitosis. Material and methods: Three electronic databases (PubMed, Scopus, and Cochrane Library) were searched prior to March 15, 2018. The review was systematically conducted and reported according to the Cochrane Handbook and the PRISMA statement. Only Randomised Clinical Trials (RCTs) were considered. Selected full-text papers were independently assessed by four investigators and any disagreements were resolved by consensus. The Cochrane Handbook was used to grade the risk of bias and the quality of evidence was rated according to GRADE. Results: Out of 363 identified studies, three RCTs on halitosis and fixed orthodontic appliances met the inclusion criteria. The risk of bias in the three studies was rated as high and the quality of evidence was rated as very low. Conclusions/clinical implications: There is a lack of scientific evidence that subjects with fixed orthodontic appliances develop halitosis during treatment. Additional well-conducted RCTs with extended periods of assessment are needed as well as consensus concerning cut-off values for the diagnosis of halitosis.

AIMS: To identify if lower incisor movements after orthodontic treatment are due to the relapse of the orthodontic treatment or due to natural growth. SUBJECTS AND METHODS: The subjects consisted of 92 patients who have had orthodontic treatment, divided into three groups, group 1: 38 individuals had no retainer in the lower jaw. Group 2: 24 individuals had a retainer 0.028 inch, a spring hard wire bonded to the mandibular canines only. Group 3: 30 individuals had a 0.0195-inch Twist-Flex wire, bonded to all mandibular incisors and canines. Study models before orthodontic treatment (T0), immediately after orthodontic treatment (T1), 6 years after orthodontic treatment (T2), and 12 years after orthodontic treatment (T3) were used for the measurements. The wires in groups 2 and 3 were removed after mean 2.6 years (SD 1.49). Little Irregularity Index (LII), inter-canine distance, available mandibular anterior space, and number of crowded incisors were registered. A Tooth Displacement Index (TDI) was developed to measure the tooth displacement directions at T0 and T3. RESULTS: The LII showed equal values before treatment (T0) and at the follow-up registrations (T2 and T3). But about 25 per cent of the tooth displacements at T2 and T3 did not exist before treatment, at T0. This indicates usual growth changes and not relapse of the orthodontic treatment. CONCLUSION: As about 25 per cent of the displaced incisors can be considered as an effect of natural growth, not a relapse of the orthodontic treatment, it is valuable to use a displacement index in combination with other variables for investigations of stability after orthodontic treatment. Importance of the present study is that it is possible to differ between relapse and usual growth changes.

Abstract Objectives: To evaluate the space-maintaining capacity of a titanium mesh or a bioresorbable mesh after periosteal expansion and to assess bone formation under a titanium mesh or a bioresorbable mesh on the lateral border of the mandible by qualitative and quantitative histological analysis. Material and methods: In 13 rabbits, a self-inflatable soft tissue expander was placed intraorally, bilaterally under the mandibular periosteum via an extra oral approach. After 2 weeks, the expanders were removed and a particulated onlay bone graft was placed and covered by a titanium mesh or a bioresorbable mesh. After 3 months, the animals were sacrificed and specimens were collected for histology. Results: The osmotic soft tissue expander created a subperiosteal pocket and a ridge of new bone had formed at the edges of the expanded periosteum in all sites. After the healing period of 3 months, soft tissue dehiscence was recorded in two of the sites with bioresorbable meshes. The mean bone fill was 65% under the titanium mesh and 85% under the bioresorbable mesh (P<0.05). There was no significant difference between the titanium mesh and the bioresorbable mesh regarding the height of the meshes, mesh area and mineralized bone area. Scanning electron microscopy shows that new bone is growing in direct contact with the resorbable mesh and the titanium mesh. Conclusion: This study confirms that an osmotic soft tissue expander creates a surplus of periosteum and soft tissue and that new bone can be generated under a titanium mesh or bioresorbable mesh.

About 30 % of individuals in the Swedish population will at some stage during life have treatment with orthodontic appliances. In more severe cases, when orthodontic treatment is not considered sufficient enough to correct the malocclusion, the orthodontic treatment is combined with orthognathic surgery. For these cases, a satisfying jaw relation is achieved by surgically moving the maxilla and/or the mandible into a pre-planned position.Patients due to be treated with orthognathic surgery often suffer from an impaired masticatory function, symptoms from the masti- catory muscles or temporomandibular joints (temporomandibular disorders), headaches as well as dissatisfaction with their facial aesthetics.Since orthognathic treatment is expensive, in many cases arduous to the patient and not without complications, it is important to assess the treatment outcome and if this is satisfying for the patients. Previous studies that have examined the outcome after ortho- gnathic treatment have had diverging study designs and have come to different conclusions with regard to both temporomandibular disorders and masticatory function.The overall aim of this thesis was to assess and compare the frequencies of temporomandibular disorders and the masticatory function in patients with dentofacial deformities before and after orthognathic treatment.The thesis is based on the following studies:paper i is a systematic literature review aiming to, in an evidence- based approach, answer the question whether orthognathic treatment affects the prevalence of signs and symptoms of temporomandibular disorders. The review encompasses the period from January 1966 to April 2006 and was further extended to May 2013 in the frame story of this thesis.Conclusions in Paper I and the complementary survey• There is insufficient scientific evidence for a decrease of sub diagnoses of temporomandibular disorders after orthognathic treatment.• There is limited scientific evidence for a reduction of masticatory muscle pain on palpation after orthognathic treatment.• There is insufficient scientific evidence for an effect on temporomandibular joint pain on palpation and temporomandibularjoint sounds from orthognathic surgery.• Further controlled, well-designed studies assessing temporomandibular disorders before and after orthognathic treatment are needed to consolidate strong evidence considering treatment outcomes.papers II and III are studies comparing frequencies of temporomandibular disorders in patients with dentofacial deformities with a control group. The patients were referred for a combined orthodontic and orthognathic treatment to correct their malocclusion. The control group comprised individuals with normal occlusion or minor malocclusion traits not in need of orthodontic treatment. In Paper III, temporomandibular disorders were longitudinally analysed by assessing and comparing frequencies before and after orthognathic treatment. All individuals in the studies were diagnosed according to the research diagnostic criteria for temporomandibular disorders.Conclusions in Papers II and III• Patients due to be treated with orthognathic surgery had more signs and symptoms of temporomandibular disorders and a higher frequency of diagnosed temporomandibular disorders compared with the age- and gender matched control group.• Patients with dentofacial deformities, corrected by orthodontic treatment in conjunction with orthognathic surgery, had a positive treatment outcome in respect of myofascial pain and arthralgia.• After treatment the frequency of temporomandibular disorders in the treatment group was low and at an equivalent level of that in the control group.paper iV evaluates the self-estimated masticatory ability and the masticatory performance before and after orthognathic treatment in the same individuals as in Paper II and III.Conclusions in Paper IV• Masticatory ability and performance increased after orthognathic treatment.• The number of occlusal contacts and severity of overall symptoms of TMD influenced both the masticatory ability and performance.• Open bite had a negative effect on masticatory performance.Key conclusions and clinical implications:Patients with dentofacial deformities diagnosed with temporomandibular disorders do in most cases benefit from orthognathic treatment. In addition, masticatory ability and performance, which is impaired in patients with dentofacial deformities, improve after treatment. Thus, patients with dentofacial deformities that are to be treated with orthodontics in combination with orthognathic surgery can be recommended the treatment in order to relieve symptoms of TMD and impaired mastication.

Objective: To answer the question whether temporomandibular disorders (TMD) were more common in a group of individuals referred for orthognathic surgery than in a control group. The null hypothesis was that neither the frequency of signs and symptoms of TMD or diagnosed TMD would differ between the patient group and a control group. Materials and Methods: A sample of 121 consecutive patients referred for orthognathic surgery at the Department of Oral Maxillofacial Surgery, Malmö University Hospital, Sweden, was interviewed and examined regarding signs and symptoms of TMD and headaches. A control group was formed by 56 age- and gender-matched individuals attending the Department of Oral Diagnosis, Faculty of Odontology, Malmö University, Sweden, and Public Dental Health Clinic in Oxie, County of Skane, Sweden. TMD diagnoses were used according to Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Results: The patient group showed more myofascial pain without limited opening, disc displacement with reduction, and arthralgia according to RDC/TMD than the control group. The patient group also had more symptoms and signs of TMD in general. Conclusions: The null hypothesis was rejected because patients who were to be treated with orthognathic surgery had more signs and symptoms of TMD and higher frequency of diagnosed TMD compared with the matched control group.

OBJECTIVE: To answer the question whether orthognathic surgery does affect the prevalence of signs and symptoms of temporomandibular disorders (TMDs). MATERIALS AND METHODS: A literature survey in the PubMed and Cochrane Library electronic databases was performed and covered the period from January 1966 to April 2006. The inclusion criteria were controlled, prospective or retrospective studies comparing TMDs before and after orthognathic surgery in patients with malocclusion. There were no language restrictions, and three reviewers selected and extracted the data independently. The quality of the retrieved articles was evaluated by four reviewers. RESULTS: The search strategy resulted in 467 articles, of which 3 met the inclusion criteria. Because of few studies with unambiguous results and heterogeneity in study design, the scientific evidence was insufficient to evaluate the effects that orthognathic surgery had on TMD. Moreover, the studies had problems with inadequate selection description, confounding factors, and lack of method error analysis. CONCLUSION: To obtain reliable scientific evidence, additional well-controlled and well-designed studies are needed to determine how and if orthognathic surgery alters signs and symptoms of TMD.

Objective: To answer the question whether temporomandibular disorders (TMD) were more common in a group of individuals referred for orthognathic surgery than in a control group. The null hypothesis was that neither the frequency of signs and symptoms of TMD or diagnosed TMD would differ between the patient group and a control group. Materials and Methods: A sample of 121 consecutive patients referred for orthognathic surgery at the Department of Oral Maxillofacial Surgery, Malmö University Hospital, Sweden, was interviewed and examined regarding signs and symptoms of TMD and headaches. A control group was formed by 56 age- and gender-matched individuals attending the Department of Oral Diagnosis, Faculty of Odontology, Malmö University, Sweden, and Public Dental Health Clinic in Oxie, County of Skane, Sweden. TMD diagnoses were used according to Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Results: The patient group showed more myofascial pain without limited opening, disc displacement with reduction, and arthralgia according to RDC/TMD than the control group. The patient group also had more symptoms and signs of TMD in general. Conclusions: The null hypothesis was rejected because patients who were to be treated with orthognathic surgery had more signs and symptoms of TMD and higher frequency of diagnosed TMD compared with the matched control group.

OBJECTIVE: To answer the question whether temporomandibular disorders (TMD) were more common in a group of individuals referred for orthognathic surgery than in a control group. The null hypothesis was that neither the frequency of signs and symptoms of TMD or diagnosed TMD would differ between the patient group and a control group. MATERIALS AND METHODS: A sample of 121 consecutive patients referred for orthognathic surgery at the Department of Oral Maxillofacial Surgery, Malmö University Hospital, Sweden, was interviewed and examined regarding signs and symptoms of TMD and headaches. A control group was formed by 56 age- and gender-matched individuals attending the Department of Oral Diagnosis, Faculty of Odontology, Malmö University, Sweden, and Public Dental Health Clinic in Oxie, County of Skane, Sweden. TMD diagnoses were used according to Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). RESULTS: The patient group showed more myofascial pain without limited opening, disc displacement with reduction, and arthralgia according to RDC/TMD than the control group. The patient group also had more symptoms and signs of TMD in general. CONCLUSIONS: The null hypothesis was rejected because patients who were to be treated with orthognathic surgery had more signs and symptoms of TMD and higher frequency of diagnosed TMD compared with the matched control group.

OBJECTIVES: The aim of this study was to investigate the self-estimated masticatory ability and masticatory performance in patients with dentofacial deformities before and after orthognathic treatment; in comparison to an age- and gender-matched control group. SUBJECTS AND METHODS: The masticatory ability and masticatory performance were evaluated in 121 consecutive patients (treatment group), referred for orthognathic treatment. Eighteen months after treatment, 98 patients (81%) completed a follow-up examination. Masticatory ability was assessed on a visual analog scale, while the masticatory performance was evaluated by a masticatory test using round silicon tablets. Signs and symptoms of temporomandibular disorders (TMD) were registered by a clinical examination and a questionnaire. The control group comprised 56 age- and gender-matched subjects who were examined at baseline. RESULTS: At the baseline examination, the treatment group had a significantly lower masticatory ability and performance compared with the control group. After treatment, the masticatory ability significantly improved in the treatment group and reached the same level as in the control group. The masticatory performance index increased significantly but was still lower than in the control group. Both the masticatory ability and masticatory performance were affected by the number of occlusal contacts during maximal biting pressure and by the self-estimated overall symptoms of TMD. CONCLUSIONS: Patients with dentofacial deformities, corrected by orthognathic treatment, have a significant positive treatment outcome in respect of masticatory ability and masticatory performance. Furthermore, the occlusion and symptoms of TMD have an impact on both masticatory ability and masticatory performance.

Abstract The aims of the study were to investigate the alteration of temporomandibular disorders (TMD) after correction of dentofacial deformities by orthodontic treatment in conjunction with orthognathic surgery; and to compare the frequency of TMD in patients with dentofacial deformities with an age and gender matched control group. TMD were evaluated in 121 consecutive patients (treatment group), referred for orthognathic surgery, by a questionnaire and a clinical examination. 18 months after treatment, 81% of the patients completed a follow-up examination. The control group comprised 56 age and gender matched subjects, of whom 68% presented for follow-up examination. TMD were diagnosed according to research diagnostic criteria for TMD. At baseline examination, the treatment group had a higher frequency of myofascial pain (P=.035) and arthralgia (P=.040) than the control group. At follow-up, the frequencies of myofascial pain, arthralgia and disc displacement had decreased in the treatment group (P=.050, P=.004, P=.041, respectively). The frequency of TMD was comparable in the two groups at follow-up. Patients with dentofacial deformities, corrected by orthodontic treatment in conjunction with orthognathic surgery, seem to have a positive treatment outcome in respect of TMD pain

OBJECTIVES: To evaluate the effectiveness of surgical and nonsurgical treatment of temporomandibular joint (TMJ) luxation. MATERIALS AND METHODS: This systematic literature review searched PubMed, the Cochrane Library, and Web of Science databases to identify randomized controlled trials on TMJ luxation treatment published between the inception of each database and 26 March 2018. RESULTS: Two authors assessed 113 unique abstracts according to the inclusion criteria and read nine articles in full text. Eight articles comprising 338 patients met the inclusion criteria, but none of these evaluated surgical techniques. Three studies including 185 patients concerned acute treatment with manual reduction of luxation while five studies including 153 patients evaluated minimally invasive methods with injection of autologous blood or dextrose prolotherapy for recurrent TMJ luxation. These studies reported that mouth opening after treatment was reduced and that independent of type of injection, recurrences of TMJ luxation were rare in most patients. CONCLUSIONS: In the absence of randomized studies on surgical techniques, autologous blood injection in the superior joint space and pericapsular tissues with intermaxillary fixation seems to be the treatment for recurrent TMJ luxation that at present has the best scientific support. Well-designed studies on surgical techniques with sufficient numbers of patients, long-term follow-ups, and patient experience assessment are needed for selection of the optimal surgical treatment methods. CLINICAL RELEVANCE: Autologous blood injection combined with intermaxillary fixation can be recommended for patients with recurrence of TMJ luxation.

Insufficient regeneration of missing bone and soft-tissue may presentaesthetic or functional problems in patients indicated for dentalimplant surgery. Several techniques such as bone grafts, bone substitutesand guided tissue regeneration (GTR) have been described torebuild a compromised alveolar ridge. Adequate soft-tissue coverageof grafted bone and titanium-mesh is important to avoid exposurewhich may result in loss of the bone graft.The general aim of this thesis was to evaluate use of an osmotictissue expander for expanding intra-oral soft tissue – creating a surplusof soft tissue – in preparation for onlay bone grafting.An experimental rabbit model was used in studies (I), (II) and (III).In (I) an osmotic soft-tissue expander was placed bilaterally on thelateral wall of the mandible via an extra-oral approach. After twoweeks of expansion the rabbits were killed and specimens were collectedfor histology. No inflammatory reaction and no resorbtion ofthe cortical bone occured. The periosteum was expanded and newbone formation was seen in the edges of the expander.In (II) and (III) the expander was placed under the periosteum in thesame way as in (I): bilaterally in 13 rabbits in (II) and unilaterally in11 rabbits in (III).After two weeks of expansion the expander was identified andremoved. In (II) particulated bone was placed at the recipient siteprotected by a titanium mesh in one site and a bio-resorbable meshon the other site. In (III), DBBM particles and bone particles collected from the lateralborder of the mandible separated by a collagen membrane wasplaced at the recipient site. The graft was protected by a pre-benttitanium mesh covered by a collagen membrane.After a healing period of 3 months specimens were collected forhistological and SEM examination. New bone was growing in directcontact with the titanium mesh and bio resorbable mesh. The newlyformed bone had the same calcium content as the mature bone in thebase of the mandible.In the clinical study (IV) 20 patients were consecutively recruitedand randomised into two groups.The experimental group (ten patients) had an osmotic soft tissueexpander implanted. After two weeks of expansion the expanderwas removed and a particulated bone graft protected by a titaniummesh and a collagen membrane was fixed to the recipient site. Titaniumimplants were installed after a healing period of 6 months.The patients in the reference group had a bone block grafted fromthe anterior ramus fixated to the recipient site with one or two titaniummini screws. Implants were installed after a healing period of6 months.A three dimensional optical measuring device was used to measurealterations in the soft tissue profile before each surgical procedure.The three-dimensional changes were then analysed on a PC.The results from the clinical study in patients confirmed the resultsfrom the experimental rabbit studies. The osmotic tissue expanderexpanded the soft tissue. Expander perforations of the soft tissueoccurred in two patients. The optical measurements demonstrated apositive volume gain after soft tissue expansion and bone grafting.The expanded tissue could be used to cover a bone graft. There stillwas a risk of mesh exposure, even after soft tissue expansion, whichoccurred in two patients. In both groups, implants could be installedin the grafted bone in positions that would allow the crowns to fitaesthetically into the dental arch.

OBJECTIVES: To evaluate the space-maintaining capacity of titanium mesh covered by a collagen membrane after soft tissue expansion on the lateral border of the mandible in rabbits, and to assess bone quantity and quality using autogenous particulate bone or bone-substitute (Bio-Oss(®) ), and if soft tissue ingrowth can be avoided by covering the mesh with a collagen membrane.

MATERIAL AND METHODS: In 11 rabbits, a self-inflatable soft tissue expander was placed under the lateral mandibular periosteum via an extra-oral approach. After 2 weeks, the expanders were removed and a particulated onlay bone graft and deproteinized bovine bone mineral (DBBM) (Bio-Oss(®) ) were placed in the expanded area and covered by a titanium mesh. The bone and DBBM were separated in two compartments under the mesh with a collagen membrane in between. The mesh was then covered with a collagen membrane. After 3 months, the animals were sacrificed and specimens were collected for histology.

RESULTS: The osmotic soft tissue expander created a subperiosteal pocket and a ridge of new bone formed at the edges of the expanded periosteum in all sites. After the healing period of 3 months, no soft tissue dehiscence was recorded. The mean bone fill was 58.1±18% in the bone grafted area and 56.9±13.7% in the DBBM area. There was no significant difference between the autologous bone graft and the DDBM under the titanium mesh with regard to the total bone area or the mineralized bone area. Scanning electron microscopy showed that new bone was growing in direct contact with the DBBM particles and the titanium mesh. There is a soft tissue ingrowth even after soft tissue expansion and protection of the titanium mesh with a collagen membrane.

CONCLUSION: This study confirms that an osmotic soft tissue expander creates a surplus of periosteum and soft tissue, and that new bone can subsequently be generated under a titanium mesh with the use of an autologous bone graft or DBBM.

To determine whether it is possible to vertically augment bone utilizing a block graft from compressed titanium granules mainly used previously for contained bone defects and to determine whether there exists a difference in osteoconductive properties between the white and the grey granules. In 11 rabbits, 4 titanium blocks were inserted on each rabbit's skull bone according to a randomized scheme. These blocks were made from standardized compressed titanium granules. Type A: PTG grey, small granules (Pourus Titanium Granules, Tigran, Malmo, Sweden); Type B: PTG grey, large granules; Type C: PTG white, small granules; Type D: PTG white large granules. After 12 weeks, the animals were sacrificed and specimens were collected for histology and mu CT scanning. From both the mu CT and histology, it can be said that bone formation was successfully achieved for all groups, and the granules maintained their volume. The histomorphometric BA (bone area) evaluation in the entire grafted area presented that there were no statistical differences between all groups tested. The lowest 1/4 BA in contact with the rabbit skull presented that groups A and C presented the highest mean BA, and group A presented significantly higher BA than that of group D (p = 0,049). No significant differences were noted between groups A, B and C. Within the limitation of this study, no differences were noted between small white or grey PTG blocks. The large granules presented less bone ingrowth area compared to the small granules and this trend was regardless of the different PTG types. The entire grafted area was not filled with new bone suggesting that bone migration occurred mostly from the existing cortical bone side suggesting contact osteogenesis.

To evaluate the outcome of intraoral soft tissue expansion by measuring the profile change using objective 3D metering equipment and to evaluate localized bone grafting after soft tissue expansion with regard to gain of bone and complications.

Objectives: The study aim was to evaluate the prevalence of self-reported temporomandibular disorders (TMD) and acceptance or nonacceptance of such disorders in adult patients attending all public dental health services in the County of Sormland, Sweden, during a 3-year period, 2011-2013. Methods: Two questions were asked about TMD and the voluntary mouth-opening capacity was measured. The results were registered in a score 0-3. The registration was completed with a question about each patient's acceptance or nonacceptance of their condition. Results: More than 73,000 registrations of the TMD condition were performed in general dental clinics from 2011 to 2013. The mean prevalence of a TMD score of 1-3 was 5% and was consistent over these years. Seventy percent of these patients were women. The peak prevalence of TMD was registered in patients aged 30-45years (38%), and the frequency declined in older age groups. Reduced voluntary mouth-opening capacity (<= 35 mm) was found in less than 2% of the participants. About one-fifth of the patients with a TMD-score of 1-3 did not accept their condition and wanted professional care. The frequency of nonacceptance of the condition increased with the severity of symptom score: 15%, 27%, and 49% for scores 1, 2, and 3, respectively. Conclusions: This study shows that the prevalence of self-reported TMD in adult patients was consistent from 2011 to 2013 and should be considered as a public health issue in Sweden. Patients with more severe TMD pain symptoms wanted care more frequent. The annual clinical calibrations should be continued to achieve an acceptable level of registration.

Objective. To analyse the prevalence of temporomandibular disorders and related pain (TMD-pain) among adult recall patients in general dental practice. Materials and methods. From November 2006 to September 2008, all adults attending a Swedish Public Dental Service (PDS) clinic for recall examination were asked two standardized questions about temporomandibular pain and dysfunction. Mouth-opening capacity was measured. The responses to the questions and mouth-opening capacity were combined to give a TMD-pain score, on a scale of 0-3. The patients' acceptance of their TMD condition was also noted. Results. The subjects comprised 2837 adults (53% females, 47% men). Of the total sample, 4.9% reported a TMD-pain score of 1-3. The gender difference was significant: women predominated (p < 0.003). Forty-three per cent of those with TMD-pain scores of 1-3 (36% men, 47% women) considered that the condition warranted treatment, especially those registering a pain score (significant difference between pain and dysfunction groups, p < 0.000). Conclusions. The TMD-pain score shows promise as a useful instrument for detecting and recording TMD-pain. The prevalence of TMD disclosed in the study is high enough to be considered a public health concern. Most of the subjects with lower scores on the TMD-pain scale accepted their condition as not severe enough to require treatment.

Specialistinstanser i bettfysiologi möter i huvudsak patienter som har en långvarig och svårt smärtproblematik. Under 1900-talet har dock även behandling av obstruktiv sömnapné tillkommit. Ofta är det en läkare som remitterat patienten till den bettfysiologiska kliniken. Denna studie visar att bettfysiologen är en viktig länk mellan tandvården och sjukvården vid utredning och behandling av orofacial smärta. Syf-tet med studien var att jämföra orsakerna till remisser till bettfysiologi. En jämförelse gjordes mellan fyra specialistkliniker i bettfysiologi un-der en 4-månadersperiod år 2001. De flesta remitterade patienter var kvinnor i åldern 20 år och uppåt. Bland de remitterade kvinnorna var smärta den dominerande orsaken medan männen lika ofta remittera-des för sömnstörning som för smärta. 86 procent av patienterna som remitterats för smärta värderade smärtans intensitet som måttlig till väldigt svår. Hos 80 procent av dessa patienter var smärtan långvarig.

This thesis is focused on (I) the outcome of reconstructive treatment of peri-implant defects and (II) risk factors for the development of peri-implantitis.

Background

An increasing number of individuals have dental implant-supported reconstructions. The long-time survival rate of dental implants is good, but complications do occur. Accumulation of bacteria on oral implants and the development of a pathogenic biofilm at the mucosal margin will result in inflammatory responses diagnosed as peri-implant mucositis(PiM). Furthermore, PiM may progress to peri-implantitis (Pi) involving the implant-supporting bone and potentially result in a severe inflammatory process resulting in alveolar bone destruction and consequently implantloss. Currently, Pi is a common clinical complication following implant therapy.The prevalence of peri-implantitis has been reported to be around 20 %. Susceptibility to infections and a history of periodontitis are considered as important risk indicators for peri-implantitis. It seems logical that a past history of periodontitis is linked to an increased risk of peri-implantitis. It is possible that other patient-associated factors such as a smoking habit, and presence of general diseases may also be linked to a higher risk for developing peri-implantitis.Treatment of peri-implantitis is difficult. Non-surgical treatment modalities may not be sufficient to resolve the inflammatory process to obtain healthy conditions.Surgical treatment of peri-implantitis has commonly been employed in clinical practice to obtain access to the implant surface thereby increasing the possibility to effectively decontaminate the implant surfaces.The effectiveness and long-term outcomes of reconstructive surgical treatments of peri-implantitis has been debated. The scientific evidence suggests that regular supportive care is an essential component in order to maintain and secure long-term results following treatment of peri-implantitis.

Aims

1. To assess the short-term efficacy of reconstructive surgical treatmentof peri-implantitis  (Study I).

2. To analyse risk factors related to the occurrence of peri-implantitis(Study II).

3. To assess the importance of defect configuration on the healing response after reconstructive surgical therapy of peri-implantitis (Study III).

4. To assess the long-term efficacy of reconstructive surgical treatmentof peri-implantitis (Study IV).

MethodsFour studies were designed to fulfil the aims:

- A single-blinded prospective randomised controlled longitudinal human clinical trial evaluating the clinical and radiographic results of reconstructive surgical treatment of peri-implantitis defects usingeither AB or BDX.

- A retrospective analysis of individuals with either peri-implantitis, or presenting with either peri-implant health, or peri-implant mucositis assessing the likelihood that peri-implantitis was associated with a history of systemic disease, a history of periodontitis, and smoking.

- A prospective study evaluating if the alveolar bone defect configuration at dental implants diagnosed with peri-implantitisis related to clinical parameters at the time of surgical intervention and if the short- and long-term outcome of surgical intervention of peri-implantitis is dependent on defect configuration at the time of treatment.

- A prospective 5-year follow-up of patients treated either with AB or BDX.

Results

- The success for both surgical reconstructive procedures was limited. Nevertheless, bovine xenograft provided evidence of more radiographic bone fill than AB. Improvements in PD, BOP, and SUP were observed for both treatment modalities

-In relation to a diagnosis of peri-implantitis, a high likelihood of comorbidity was expressed in the presence of a history of periodontitis and a medical history of cardiovascular disease

- The buccal-lingual width of the alveolar bone crest was explanatory to defect configuration

- 4-wall defects and deeper defects demonstrated more radiographic evidence of defect fill

- Reconstructive surgical treatment of peri-implant defects may result in successful clinical outcomes, that can be maintained over at least five years

- The use of BDX is more predictable than use of harvested bone from the patient (AB)

Conclusions

The study results suggest that a bovine xenograft provides better radiographic evidence of defect fill than the use of autogenous bone harvested from cortical autologous bone grafts.Treatment with bone grafts to obtain radiographic evidence of defect fill is more predictable at 3- and 4-wall defects than at peri-implantitis bone defects with fewer bone walls.In relation to a diagnosis of peri-implantitis, a high likelihood of comorbidity was found for a history of periodontitis and a history of cardiovascular disease.

OBJECTIVES: The aim of this study was to assess the long-term efficacy of reconstructive treatment of peri-implantitis intraosseous defects.

MATERIAL AND METHODS: Peri-implant intraosseous defects were augmented using either an autogenous bone graft (AB) or a bovine-derived xenograft (BDX) in combination with a collagen membrane. Maintenance was provided every third month.

RESULTS: In the AB group, 16 patients with 25 implants remained at year five. In the BDX group, 23 patients with 38 implants remained. Between baseline and year 5, bleeding on probing (BOP) and probing pocket depth (PPD) scores were reduced in both groups (p < .001). In the AB and BDX groups, mean PPD between baseline and year five was reduced by 1.7 and 2.8 mm, respectively. The difference between groups was significant (p < .001). In the AB group, the mean bone level change at implant level between baseline and years three and five was-0,2 and -0.7 mm, respectively. In the BDX group, the mean bone level change at implant level between baseline and years three and five was 1.6 and 1.6 mm, respectively. The difference between the groups was significant (p < .001). Successful treatment (no bone loss, no probing pocket depth (PPD) > 5 mm, no suppuration, maximum one implant surface with bleeding on probing (BOP) at year five) was obtained in 9/25 implants (36%) in the AB group and in 29/37 implants (78.3%) in the BDX group.

CONCLUSIONS: Reconstructive surgical treatment of peri-implant defects using BDX resulted in more predictable outcomes than using autogenous bone over 5 years.

OBJECTIVES: To assess if (I) the alveolar bone defect configuration at dental implants diagnosed with peri-implantitis is related to clinical parameters at the time of surgical intervention and if (II) the outcome of surgical intervention of peri-implantitis is dependent on defect configuration at the time of treatment.

MATERIALS AND METHODS: In a prospective study, 45 individuals and 74 dental implants with ≥ 2 bone wall defects were treated with either an autogenous bone transplant or an exogenous bone augmentation material. Defect fill was assessed at 1 year.

RESULTS: At baseline, no significant study group differences were identified. Most study implants (70.7%, n = 53) had been placed in the maxilla. Few implants were placed in molar regions. The mesial and distal crestal width at surgery was greater at 4-wall defects than at 2-wall defects (p = 0.001). Probing depths were also greater at 4-wall defects than at 2-wall defects (p = 0.01). Defect fill was correlated to initial defect depth (p < 0.001). Defect fill at 4-wall defects was significant (p < 0.05).

CONCLUSIONS: (I) The buccal-lingual width of the alveolar bone crest was explanatory to defect configuration, (II) 4-wall defects demonstrated more defect fill, and (III) deeper defects resulted in more defect fill.

BACKGROUND: Limited evidence exists on the efficacy of regenerative treatment of peri-implantitis.

MATERIAL AND METHODS: Subjects receiving antibiotics and surgical debridement were randomly assigned to placement of autogenous bone (AB) or bovine-derived xenograft (BDX) and with placement of a collagen membrane. The primary outcome was evidence of radiographic bone fill and the secondary outcomes included reductions of probing depth (PD) bleeding on probing (BOP) and suppuration.

RESULTS: Twenty-two subjects were included in the AB and 23 subjects in the BDX group. Statistical analysis failed to demonstrate differences for 38/39 variables assessed at baseline. At 12 months, significant better results were obtained in the BDX group for bone levels (p < 0.001), BOP (p = 0.004), PI (p = 0.003) and suppuration (p < 0.01). When adjusting for number of implants treated per subject, a successful treatment outcome PD ≤ 5.0 mm, no pus, no bone loss and BOP at 1/4 or less sites the likelihood of defect fill was higher in the BDX group (LR: 3.2, 95% CI: 1.0-10.6, p < 0.05).

CONCLUSIONS: Bovine xenograft provided more radiographic bone fill than AB. The success for both surgical regenerative procedures was limited. Decreases in PD, BOP, and suppuration were observed.

Periodontitis and dental caries are two of the most prevalent human diseases, affecting nearly 2 billion worldwide. Persistence is largely attributed to the formation of biofilms (plaque) by oral bacteria, which left undisturbed lead to destruction of surrounding tissues and increase the risk for secondary disease. As current treatments such as mechanical removal and adjunctive therapies can be inadequate, there is a need for new anti-plaque chemical agents. Stabilized hypochlorous acid (sHOCl) has emerged as a potential anti-biofilm agent in areas such as wound therapy but its use in treating oral diseases remains unknown. Therefore, our aim in this thesis was to assess the role of sHOCl as an antimicrobial agent for use in the oral cavity.

We found that at low concentrations, sHOCl was effective in killing bacteria within mixed-species in vitro models resembling periodontitis and dental caries. Moreover,  sHOCl  displayed  higher  antibiofilm  activity  compared  to chlorhexidine, whilst not damaging tested oral surfaces. At sub-lethal levels, sHOCl was observed to target multiple cellular components through oxidative stress in Streptococcus biofilms. Simultaneously, work on our models revealed a possible new application of CFSE-based dyes in microscopy for the live-imaging of biofilms. In particular, multi-dye compatibility opens up the possibilities for future research employing mixed-species biofilms. Finally, our preliminary findings also indicate that sHOCl may permit a selective re-growth of biofilms following exposure.

Taken together, the results of this thesis lay the groundwork for investigations of sHOCl as an antibiofilm agent, and continue to push microbial research towardsmore relevant models.

BACKGROUND: Caries and periodontitis are amongst the most prevalent diseases worldwide, leading to pain and loss of oral function for those affected. Prevention relies heavily on mechanical removal of dental plaque biofilms but for populations where this is not achievable, alternative plaque control methods are required. With concerns over undesirable side-effects and potential bacterial resistance due to the use of chlorhexidine gluconate (CHX), new antimicrobial substances for oral use are greatly needed. Here we have investigated the antimicrobial effect of hypochlorous acid (HOCl), stabilized with acetic acid (HAc), on oral biofilms and compared it to that of CHX. Possible adverse effects of stabilized HOCl on hydroxyapatite surfaces were also examined.

METHODS: Single- and mixed-species biofilms of six common oral bacteria (Streptococcus mutans, Streptococcus gordonii, Actinomyces odontolyticus, Veillonella parvula, Parvimonas micra and Porphyromonas gingivalis) within a flow-cell model were exposed to HOCl stabilized with 0.14% or 2% HAc, pH 4.6, as well as HOCl or HAc alone. Biofilm viability was assessed in situ using confocal laser scanning microscopy following LIVE/DEAD® BacLight™ staining. In-situ quartz crystal microbalance with dissipation (QCM-D) was used to study erosion of hydroxyapatite (HA) surfaces by stabilized HOCl.

RESULTS: Low concentrations of HOCl (5 ppm), stabilized with 0.14% or 2% HAc, significantly reduced viability in multi-species biofilms representing supra- and sub-gingival oral communities, after 5 min, without causing erosion of HA surfaces. No equivalent antimicrobial effect was seen for CHX. Gram-positive and Gram-negative bacteria showed no significant differential suceptibility to stabilized HOCl.

CONCLUSIONS: At low concentrations and with exposure times which could be achieved through oral rinsing, HOCl stabilized with HAc had a robust antimicrobial activity on oral biofilms, without causing erosion of HA surfaces or affecting viability of oral keratinocytes. This substance thus appears to offer potential for prevention and/or treatment of oral biofilm-mediated diseases.

Introduction: In orthognathic surgery, understanding the patient’s motives for treatment is a key factor for postoperative patient satisfaction and treatment success. In countries/systems where orthognathic surgery is funded by public means, patients are referred mainly due to functional problems, although studies of quality of life related changes after treatment indicate that psychosocial and aesthetic reasons might be equal or more important for the patient. There is no available validated condition specific instruments in the Swedish language for quality of life evaluation of patients with dentofacial deformities. Aims/objectives: Cross cultural translation and adaptation of the English-language instrument ‘Orthognathic Quality of Life Questionnaire’ (OQLQ) into Swedish. Methods: OQLQ was translated into Swedish. A total of 121 patients in four groups were recruited and the Swedish version of the OQLQ (OQLQ-S) was tested by psychometric methods. Reliability was assessed by internal consistency and test–retest reliability. Validity was evaluated by face, convergent and discriminant validity. Results/findings and conclusions: OQLQ-S is reliable and showed good construct validity and internal consistency and can be used in a Swedish speaking population as a complement to clinical variables to evaluate patients with dentofacial deformity.

Guld har i många år använts som rekonstruktionsmaterial vid bettrehabilitering. Mer än 50% av Sveriges vuxna befolkning har kronor och/eller broar framställda i guldlegering och guld används också till stift i rotfyllda tänder, på vilka sedan kronor kan fästas. Guld har länge betraktats vara inert, dvs. ej kunna ge några reaktioner vid användning i kroppen, men på senare år har en ökad frekvens av kontaktallergi mot guld kunnat konstateras. Kontaktallergi är en typ av allergi, som vid upprepad kontakt med ämnet kan ge patienten en reaktion i hud och slemhinna. När det gäller guld kan kontaktallergi uppstå t.ex. under guldringar, av örhänge eller av halsband. När man utreder patienter för kontaktallergi mot guld – s.k. lapptestning, fäster man en häfta med guldsaltet guldnatriumtiosulfat (GSTS) på ryggen i 48 timmar. Patienten tar efter dessa två dygn bort testlappen och 3–4 samt 7 dagar efter exponeringen värderas den eventuellt uppkomna reaktionen av en hudläkare. Reaktionerna kan klassas som ospecifika irritationsreaktioner, negativa reaktioner, tveksamma reak-tioner och allergiska (positiva) reaktioner av eksemtyp. 1991 började man i Malmö rutinmässigt använda GSTS vid lapptestning av kontaktallergi mot guld, och då kunde konstateras att 10 % av de testade uppvisade kontaktallergi mot guld. Man har också visat att ett positivt lapptest är en manifestation av kontaktallergi. GSTS är, efter nickelsulfat, det näst vanligaste allergenet, som ger positiv hudreaktion vid rutintestning av eksempatienter. Detta tillsammans med en enkätstudie, som indikerade att kontaktallergi för guld var överrepresenterat hos patienter som hade guld i munnen, utgör bakgrunden till detta avhandlingsprojekt. I det första delarbetet studerades om dentalt guld (kronor, broar, inlägg) kunde sättas i samband med kontaktallergi för guld. Patienterna som ingick i studien var patienter som skulle testas eftersom de hade eksem. Resultaten visade att de patienter som vid tandläkarundersökning visat sig ha guld i munnen också i större utsträckning hade kontaktallergi för guld vid lapptestning. Symtom i munnen eller tecken på munslemhinnereaktioner kunde dock inte sättas i samband med dentalt guld eller positivt lapptest för guld. Däremot kunde det konstateras att de som hade mycket guld i munnen i större utsträckning hade kontaktallergi mot guld. I delarbete två studerades guldhalten i blodet hos samma patientpopulation. Det kunde konstateras att de patienter som hade dentalt guld hade förhöjda värden av guld i blod. I tredje delarbetet undersöktes mängden guld i blod efter att patienterna fått guldinlägg, vilket motsvarar en krona men med en fyllnings utsträckning. Patienterna hade mer guld i blodet efter att inläggen satts in jämfört med mängden guld i blod innan inläggen sattes fast. Fortfarande 15 år efter att inläggen sattes in hade patienterna förhöjda värden av guld i blod, vilket måste tolkas som en kontinuerlig frisättning av guld från dentalt guld till blod. Förhöjda värden av guld i blod har visat sig ha betydelse för hudens reaktion i kontakt med guld. Huruvida det föreligger ett samband mellan dentalt guld, kontaktallergi mot guld och munslemhinnelesioner, är inte väl utrett. Dock har studier på patienter med oral lichen indikerat att dessa patienter skulle kunna vara allergiska mot guld, men även mot andra tandvårdsmaterial. I fjärde delarbetet undersöktes därför patienter med oral lichen, med avseende på kontaktallergi mot guld i jämförelse med kontrollpatienter, vilka var remitterade till Yrkes- och miljödermatologiska avdelningen, Hudkliniken i Malmö, för misstanke om allergiskt kontakteksem. I denna studie kunde man finna en numerär skillnad avseende kontaktallergi för guld men inte någon statistisk skillnad mellan grupperna. Det är därför av vikt att i fortsatta studier, med större undersökningsmaterial, försöka utröna om det finns ett statistiskt säkert samband mellan oral lichen och kontaktallergi mot guld eller andra tandvårdsmaterial eftersom dessa patienter kan uppleva perioder med stora besvär, vilka kan försvåra både födointag och upprätthållande av en adekvat munhygien.

Questionnaire studies have indicated that patients with dental gold will more frequently have contact allergy to gold. This study aimed at investigating the relationship between contact allergy to gold and the presence and amount of dental gold alloys. A total of 102 patients were referred for patch testing because of suspicion of contact allergy. Patch tests were performed with gold sodium thiosulphate 2% and 5%. The patients underwent an oral clinical and radiological examination. Contact allergy to gold was recorded in 30.4% of the patients, and of these 74.2% had dental gold (p=0.009). A significant correlation was found between the amount of gold surfaces and contact allergy to gold (p=0.008), but there was no statistical relationship to oral lesions. It is concluded that there is a positive relationship between contact allergy to gold and presence and amount of dental gold alloys.

The aim of the present controlled study was to investigate a possible relationship between contact allergies to potential allergens and oral lichen lesions. Eighty-three patients with oral lichen lesions (OLL) and control groups of age- and gender-matched dermatitis patients (DP, n = 83) and patch-tested dermatitis patients randomly selected from files (PSFF, n = 319) were included in the study. OLL and DP groups were patch-tested epicutaneously and examined intraorally. The frequencies of contact allergy to mercury and carvone were statistically higher in the OLL group than in the DP group. Surfaces of amalgam and composite restorations were statistically more frequent in the OLL group compared to the DP group. Contact allergy to nickel and colophony, the latter with a statistically significant difference, was more common in the DP group. The numerical difference found for nickel allergy was, however, not significant comparing the OLL and PSFF groups. Contact allergy to mercury was overrepresented in patients with OLL and has been reported in previous studies, but the present finding of an overrepresentation of contact allergy to carvone in patients with oral lichen lesions has not been reported previously. Carvone, in addition to mercury and gold, as previously suggested, can be one of the causative or maintenant factors for oral lichen lesions. Carvone-hypersensitive patients with oral lichen lesions should therefore avoid carvone-containing products for oral use.

The aetiology of oral lichen lesions is obscure. In this study the frequency of contact allergy to gold in 83 patients with oral lichen lesions was compared with that in two control groups, comprising 319 age- and gender-matched patients with dermatitis selected from files and 83 clinically examined dermatitis patients. All patients were tested epicutaneously with gold sodium thiosulphate. The two control groups tested were under examination for a tentative diagnosis of allergic dermatitis not related to oral problems. The frequency of contact allergy to gold was 28.9% in the patients with oral lichen lesions, 18.2% in patients selected from files, and 22.9% in the clinically examined control patients. The difference in frequency between patients with oral lichen lesions and those taken from files was statistically significant.

Establishing the clinical relevance of contact allergy to dental materials in patients with oral lichen lesions (OLL) may be difficult, and tests are often read only on day 3 or day 4; also, concentration of the tested allergens may vary. Several studies on dermatitis patients have shown that additional positive patch test reactions can be found after day 4. Therefore, the aim of the present study was to analyse the frequency of late positive reactions to potential allergens in patients with OLL. Eighty-three of 96 consecutive patients with biopsy-verified OLL were patch-tested with a recently developed lichen series. The patches were removed after 48 h and reactions read 3 and 7 days after application. A total of 129 contact allergies were found, and 26 (20.2 %) of the allergic reactions in 23 patients were seen on day 7 only. The 25.2 % increase in positive test reactions with an additional reading on day 7 in addition to day 3 was statistically significant. Metals were the substances with the highest frequency of late positive reactions. Patients with OLL cannot be considered properly investigated with regard to contact allergy, unless the testing has been performed with mandatory readings on day 3 (or day 4) and day 7. Late patch test readings are crucial in order to elucidate the role of contact allergy to dental materials in the aetiology of OLL.

OBJECTIVE: Several studies have reported increased levels of gold (Au) in the blood of patients with dental gold restorations. This study analyzed gold levels in blood plasma before dental gold inlay insertion, 0-12 months after, and 15 years after. MATERIAL AND METHODS: Plasma samples from 9 patients were taken before and 0-10 months after gold inlay insertion. Fifteen years after gold inlay insertion, further blood samples taken from 8 of these patients were analyzed for gold using inductively coupled plasma mass spectrometry. An oral examination was also carried out before and 15 years after gold inlay insertion. RESULTS: Gold levels in plasma were significantly higher 0-12 months after gold inlay insertion than before treatment (p=0.008). No significant difference in gold plasma levels was found between 0-12 months after and 15 years after insertion (p=0.109), although there was a significant correlation between the number of gold alloy surfaces and the amount of gold in plasma 15 years after insertion (p=0.028). CONCLUSIONS: This study supports a dose-related release of gold into plasma from dental gold restorations, a release that appears to be stable over time.

Aim: To evaluate how well the working length radiograph and obturation radiograph corresponded with the working length (WL) measured initially by electronic apex locator (EAL). Furthermore, the aim of this study was to evaluate if the quality of root canal fillings was dependent on tooth type, number of dental visits and if there was any different in treatment procedure before and during the Covid-19 pandemic. Additionally, signs of healing were evaluated if radiographs were available.

 Material and method: Patient journal and intraoral radiographs of 635 patients who had undergone endodontic treatment by students at the Faculty of Odontology at University of Malmö during 2016–2021 were evaluated. A total number of 350 patients fulfilled the inclusion’s criteria. Patient’s journal and radiographs were reviewed by two independent observers. 

Results: Of 350 teeth, in 262 teeth working length radiograph and obturation radiograph was consistent with the working length determined by EAL. Mandibular morals followed by maxillary molars and premolars were tooth types that failed to keep WL measured by EAL. Approximately 70% teeth were treated between 2-6 visits. In 84 cases radiographs were available and signs of healing were observed in 78 cases (approx. 92%). No significant differences were observed in treatment procedure before and under the Covid-19 pandemic.  

Conclusion: The root canal fillings were of good quality based on clinical and radiographic evidence. Students need more time to carry out endodontic treatment but, in most cases, root canal fillings were of good quality and periapical healing was obtained. Furthermore, the students need clearer recommendations regarding determination of WL. 

Aim: The aim of the study was to systematically review the evidence from clinical intervention trials evaluating the effect of periodontal treatment (PT) on surrogate markers on individuals diagnosed with periodontal disease (PD) and atherosclerotic cardiovascular disease (ACVD). The systematic review was based on quantitative literature. Method: A electronic search for relevant articles published between October 2012- October 2022 was carried out in the following databases: PubMed, Cochrane Library, and Web of Science. Results: The systematic search identified 686 articles, after the title and abstract screening 14 articles were read in full-text, 7 articles underwent risk of bias assessment, 1 was excluded due to high risk of bias and 6 articles were ultimately included. The results found that PT led to decreased levels of inflammatory biomarkers and surrogate markers of ACVD, improved periodontal parameters and endothelial function, and reduced levels of periodontopathogens. Conclusion: The findings indicate that PT can potentially benefit atherosclerosis by managing and improving its risk factors. As demonstrated by the small sample size further research is needed to fully determine the effects of PT on atherosclerosis.

The aim was to investigate how endogenous cytokine control of tumor necrosis factor (TNF) influences temporomandibular joint (TMJ) pain in relation to the role of anti-citrullinated peptide antibodies (ACPA) in patients with rheumatoid arthritis (RA). Twenty-six consecutive patients with TMJ RA were included. Temporomandibular joint pain intensity was assessed at rest, on maximum mouth opening, on chewing, and on palpation. Mandibular movement capacity and degree of anterior open bite (a clinical sign of structural destruction of TMJ tissues) were also assessed. Systemic inflammatory activity was assessed using the Disease Activity Score in 28 joints (DAS28) for rheumatoid arthritis. Samples of TMJ synovial fluid and blood were obtained and analyzed for TNF, its soluble receptor, soluble TNF receptor II (TNFsRII), and ACPA. A high concentration of TNF in relation to the concentration of TNFsRII in TMJ synovial fluid was associated with TMJ pain on posterior palpation on maximum mouth opening. The ACPA concentration correlated significantly to the TNF concentration, but not to the TNFsRII concentration, indicating that increased inflammatory activity is mainly caused by an insufficient increase in anti-inflammatory mediators. This study indicates that TMJ pain on palpation in patients with RA is related to a deficiency in local cytokine control that contributes to increased inflammatory activity, including sensitization to mechanical stimuli over the TMJ.

OBJECTIVE: To investigate if TNF, IL-1 or their endogenous controls, in relation to ACPA, are associated with radiological signs of ongoing temporomandibular joint (TMJ) bone tissue resorption and disc displacement in RA patients. METHODS: Twenty-two consecutive outpatients with TMJ of RA were included. Systemic inflammatory activity was assessed by DAS28. The number of painful regions in the body and ESR, CRP, RF and ACPA were analyzed. TMJ synovial fluid and blood samples were obtained and analyzed for TNF, TNFsRII, IL-1ra, IL-1sRII and ACPA. The ratios between the mediators and their endogenous control receptors were used in the statistical analysis. Magnetic resonance imaging was performed in closed- and open-mouth positions and evaluated regarding disc position and presence of condylar and temporal erosions of the TMJ. RESULTS: A high TNF level in relation to TNFsRII in TMJ synovial fluid correlated to the degree of TMJ condylar erosion. A high IL-1ra level in relation to TNF in TMJ synovial fluid was also correlated to the degree of TMJ condylar erosion. The total degree of TMJ condylar erosion was correlated with the number of painful regions. CONCLUSION: This study indicates that TNF in TMJ synovial fluid mediates TMJ cartilage and bone tissue resorption in RA. The study also suggests that the degree of endogenous cytokine control is of importance for development of bone tissue destruction.

Previous studies have demonstrated an association between gold allergy and the presence of dental gold restorations. The aim of the present study was to investigate the relationship between the concentration of gold in blood (B-Au) and the number of tooth surfaces with gold alloys in subjects with and without contact allergy to gold. In 80 patients referred for patch testing because of eczematous disease, blood samples were taken and analyzed for B-Au using inductively coupled plasma mass spectrometry. The detection limit for the Au determination was 0.04 microg/L. In addition, a dentist made a clinical and radiological examination of the patients and registered the number of dental gold surfaces. Patients with dental gold restorations had a statistically significantly higher B-Au in Mann-Whitney U test (P = 0.025), (range < 0.04-1.07 microg/L) than patients without (range < 0.04-0.15 microg/L). Furthermore, a positive correlation was found between B-Au and the number of dental gold surfaces (P < 0.01). There was no statistically significant difference in B-Au between persons with and without contact allergy to gold. The study thus indicates that gold is released from dental restorations and taken tip into the circulation.

INTRODUCTION: Oral health is part of general health, and oral diseases share risk factors with several non-communicable diseases. The World Dental Federation (FDI) has published a theoretical framework illustrating the complex interactions between the core elements of oral health (CEOHs): driving determinants, moderating factors, and general health and well-being. However, the framework does not specify which self-reported or clinical measurements to be included in the CEOHs.

OBJECTIVES: To explore oral health measurements relevant for a general adult population to be included in the CEOHs in the FDI's theoretical framework of oral health.

MATERIALS AND METHODS: A psychometric study was performed, using cross-sectional data from Sweden (N = 630, 54% women, mean age 49.7 years). The data set initially consisted of 186 self-reported and clinical measurements. To identify suitable measurements, the selection was discussed in different settings, including both experts and patients. Principal component analyses (PCAs) were performed to explore, reduce and evaluate measurements to be included in the three CEOHs. Internal consistency was estimated by Cronbach's Alpha.

RESULTS: The validation process yielded 13 measurements (four clinical, nine self-reported) in concordance with the CEOHs. PCAs confirmed robust validity regarding the construction, predicting 60.85% of variance, representing psychosocial function (number of measurements = 5), disease and condition status (number of measurements = 4), and physiological function (number of measurements = 4). Cronbach's Alpha indicated good to sufficient internal consistency for each component in the constructs (α = 0.88, 0.68, 0.61, respectively).

CONCLUSION: In a Swedish general adult population, 13 self-reported and clinical measurements can be relevant to include to operationalise CEOHs in the FDI's theoretical framework.

Objective:  The antimicrobial peptide hCAP18/LL-37 is detected in desquamated epithelial cells of human whole saliva, but the functional importance of this pool of hCAP18/LL-37 is not understood. Here, we assess the impact of homogenates of desquamated oral epithelial cells and exogenous, synthetic LL-37 on two oral bacteria: S. mutans and S. gordonii.

Material and methods:  Desquamated epithelial cells of unstimulated whole saliva were isolated and cellular and extracellular levels of hCAP18/LL-37 analyzed by ELISA. Bacterial viability was determined by BacLight Live/Dead staining and confocal laser scanning microscopy.

Results:  Desquamated oral epithelial cells harboured hCAP18/LL-37, and they spontaneously released/leaked the peptide to their medium. Exogenous, synthetic LL-37 showed cytotoxic activity against S. mutans but not S gordonii, suggesting that LL-37 acts differentially on these two types of oral bacteria. Homogenates of desquamated oral epithelial cells had no effect on S. mutans viability. Treatment with exogenous, synthetic LL-37 (8 and 10 μM) reduced S. mutans viability, whereas lower concentrations (0.1 and 1 µM) of the peptide lacked effect.

Conclusions:  Desquamated oral epithelial cells contain hCAP18/LL-37, but their cellular levels of hCAP18/LL-37 are too low to affect S. mutans viability, whereas exogenous, synthetic LL-37 has a strong effect on these bacteria.