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.

OBJECTIVES: To assess the success rate of spontaneous space closure after extraction of the first permanent molar (FPM) in the maxilla and the mandible, and to identify the factors that make spontaneous space closure most favorable in each.

MATERIALS AND METHODS: A retrospective records-based cohort study was conducted through a search of the database of the Public Dental Service, Stockholm County Council, Stockholm, for young adults born between 2000 and 2001, who underwent extraction of one or more FPM between 2006 and 2016. A total of 995 extracted teeth were identified, of which 203 teeth in 155 patients met the inclusion criteria.

RESULTS: Of the 203 extracted teeth, 166 (81.8%) did not receive any orthodontic treatment. The success rate for space closure in orthodontically treated patients was 91.9%. The success rate for spontaneous space closure was 84.3%. All unsuccessful spontaneous space closure in the maxilla occurred in patients older than 12 years. The dental developmental stage of the second permanent molar (SPM) had a statistically significant association with spontaneous space closure in the mandible (P < .001).

CONCLUSIONS: The success rate of spontaneous space closure was high (84.3%) and was higher in the maxilla (94.1%) than the mandible (74.1%). Age at time of extraction and dental developmental stage of the SPM were significant factors for successful spontaneous space closure in the maxilla and mandible, respectively.

Objective. To clarify the effect of Lactobacillus plantarum 299v on the salivary cortisol and salivary IgA levels in young adults under examination stress. Design. Forty-one students with an upcoming academic exam were included in a randomized double-blind, placebo-controlled study. The probiotic bacteria or the placebo product was administered in capsules once a day during 14 days. Saliva was collected and a perceived stress test was filled out at each sampling occasion. Saliva was collected for cortisol analysis by Electrochemiluminescence Immunoassay (ECLI) and salivary IgA was analysed by Enzyme-Linked Immunosorbent Assay (ELISA). Abundance of lactobacilli was evaluated by cultivation of saliva on selective medium and identification of L. plantarum 299v was done on randomly selected colonies by a random amplification of polymorphic DNA (RAPD) typing. Results. A significant difference in cortisol levels was found between the treatment group and the placebo group (P < 0.05), together with a significant increase in levels of lactobacilli in the treatment group compared with the placebo group (P < 0.001). No significant changes were found for salivary IgA. Conclusion. A probiotic bacterium with ability to reduce symptoms of irritable bowel syndrome (IBS) prohibited increased levels of the stress marker cortisol during the examination period. The registration number of the study is NCT02974894, and the study is registered at ClinicalTrials.gov.

Background The most advocated clinical method for diagnosing salivary dysfunction is to quantitate unstimulated and stimulated whole saliva (sialometry). Since there is an expected and wide variation in salivary flow rates among individuals, the assessment of dysfunction can be difficult. The aim of this systematic review is to evaluate the quality of the evidence for the efficacy of diagnostic methods used to identify oral dryness. Methods A literature search, with specific indexing terms and a hand search, was conducted for publications that described a method to diagnose oral dryness. The electronic databases of PubMed, Cochrane Library, and Web of Science were used as data sources. Four reviewers selected publications on the basis of predetermined inclusion and exclusion criteria. Data were extracted from the selected publications using a protocol. Original studies were interpreted with the aid of Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool. Results The database searches resulted in 224 titles and abstracts. Of these abstracts, 80 publications were judged to meet the inclusion criteria and read in full. A total of 18 original studies were judged relevant and interpreted for this review. In all studies, the results of the test method were compared to those of a reference method. Based on the interpretation (with the aid of the QUADAS tool) it can be reported that the patient selection criteria were not clearly described and the test or reference methods were not described in sufficient detail for it to be reproduced. None of the included studies reported information on uninterpretable/intermediate results nor data on observer or instrument variation. Seven of the studies presented their results as a percentage of correct diagnoses. Conclusions The evidence for the efficacy of clinical methods to assess oral dryness is sparse and it can be stated that improved standards for the reporting of diagnostic accuracy are needed in order to assure the methodological quality of studies. There is need for effective diagnostic criteria and functional tests in order to detect those individuals with oral dryness who may require oral treatment, such as alleviation of discomfort and/or prevention of diseases.

Objectives: To evaluate the cephalometric effects of premolar extraction on skeletal and dental parameters, and on the soft tissues, in patients subsequently treated with fixed appliances. Prevalence and severity of external apical root resorption due to premolar extraction were also examined.Materials and methods: The dental records of 79 patients treated with fixed appliances were retrieved (groups: extraction, n = 19; non-extraction, n = 60). Pre- and post-treatment statuses of skeletal, dentoalveolar, and soft tissue variables were analyzed on lateral cephalograms to determine change. Periapical radiographs of the maxillary incisors were assessed for external apical root resorption using the Levander & Malmgren index. The t-test, Mann-Whitney U test, chi-squared test, and Kruskal-Wallis test were used to analyze the data. Significance was set at p < .05.Results: Changes in the protrusion and proclination of the incisors and in lip position were significantly different between the groups. Prevalence of external apical root resorption in the two groups was similar.Conclusions: Our findings suggest that extraction therapy affects dentoalveolar traits but not jaw position, nor the risk of root resorption, in patients treated with fixed appliances

Background Compliance is crucial for the treatment outcome with removable appliances. Previous studies on treatment with the Twin Block appliance have focused on effectiveness in relation to other treatment methods or wear-time. Studies on different check-up intervals to improve compliance seem to be lacking. Objectives To compare the impact of two different check-up prescriptions on patient compliance and treatment outcome during treatment with Twin Block. Trial Design Two-arm parallel group, single-centre, randomized controlled trial. Materials and Methods Seventy-three patients, 38 boys, and 35 girls, mean age 11.2 years, were included and block-randomized into two groups treated with a Twin Block appliance. Group 1 was called for check-up visit every sixth week and group 2 every fourth week. Compliance was evaluated with a TheraMon (R) microsensor, moulded into the appliance, measuring wear-time. Overjet, overbite, and molar relationships were assessed on study casts before and after treatment. The treatment outcomes were analysed on an intention-to-treat basis. Results In group 1, the reduction of overjet was 5.2 mm and the mean wear-time was 6.9 hours. In group 2, the reduction was 4.7 mm and the wear-time was 6.1 hours. Seventy-four per cent of the patients presented an overjet of 4 mm or less. Wear-time did not correlate to age, gender, or severity of malocclusion. Harms No harm was observed in any patient. Lateral open bites were registered during treatment but were normalized at the end of the treatment. Limitations The trial was a single-centre study and long-term effects were not evaluated. Conclusions During treatment with the Twin Block appliance, a 4-week check-up interval did not improve treatment outcome or increase wear-time, compared to a 6-week check-up interval. The mean wear-time was 6.5 hours per day, even if the recommendation was 12 hours.

BACKGROUND: Malocclusions in adolescents might have a negative impact on oral health-related quality of life (OHRQoL). Potential confounding variables (confounders) such as age, gender, caries, and socioeconomic status may skew the real relationship between malocclusions and OHRQoL.

OBJECTIVES: To analyse the effect of malocclusions in adolescents on OHRQoL, when controlled for potential confounders.

SEARCH METHODS: Five databases (PubMed, Cochrane Library, Cinahl, Scopus, and Web of Science) were searched up to 15 June 2022.

SELECTION CRITERIA: Studies in which OHRQoL in 10-19-year olds with and without malocclusions were compared.

DATA COLLECTION AND ANALYSIS: Screening, data extraction, and quality assessments were performed by four investigators independently. Risk of bias was assessed according to the Swedish Agency for Health Technology Assessment and Assessment of Social Services (SBU) guidelines. To be included, studies had to control for confounders. Certainty of evidence was assessed with GRADE.

RESULTS: Thirteen cross-sectional studies with low and moderate risk of bias were included in the qualitative synthesis. Four of these were also included in the quantitative synthesis (meta-analysis). The 13 studies in the qualitative synthesis displayed a large variation among the indices used for malocclusion ratings, as well as in instruments measuring OHRQoL. There was moderate quality of evidence that malocclusions have a negative effect on OHRQoL. The four articles included in the quantitative synthesis (meta-analysis) measured malocclusions with DAI and OHRQoL with CPQ 11-14 short form. There was moderate quality of evidence that malocclusions have a negative effect on OHRQoL (RR/PR 1.15, 95% CI 1.12-1.18, 3672 participants).

CONCLUSIONS: There is moderate quality of evidence that malocclusions in adolescents have a negative impact on OHRQoL, after taking relevant confounders into consideration. Future studies should ideally use standardized measures for malocclusion ratings and OHRQoL.

REGISTRATION: PROSPERO. CRD42020186152.

BACKGROUND: Mouthwashes containing oral antiseptics or enzymes are suggested suitable for controlling biofilm accumulation in patients with fixed appliances and thereby limiting unwanted side effects during the orthodontic treatment.

OBJECTIVES: To evaluate the effect of an enzyme-based mouthwash on the amount of dental biofilm and the composition of the salivary microbiome in patients undergoing treatment with fixed orthodontic appliances.

TRIAL DESIGN: Randomized double-blind placebo-controlled trial.

MATERIAL AND METHODS: In total, 35 young adolescents (14-18 years) under treatment with fixed appliances were consecutively enrolled and randomly allocated to an experimental or a placebo group by opening a computer-generated numbered envelope. The subjects were instructed to rinse twice daily during an intervention period of 8 days with experimental mouthwash or placebo without active enzymes. Unstimulated whole saliva samples were collected at baseline and after 8 days. The participants and examiner were blinded for the allocation. The primary outcome was the Orthodontic Plaque Index (OPI) and the secondary was the composition of the salivary microbiome.

RESULTS: In total, 28 adolescents (21 females and 7 males) completed the trial and there were no differences in age, clinical, or microbial findings between the test (n = 14) and the placebo group (n = 14) at baseline. We found a decreased OPI in the test group after 8 days and the difference was statistically significant compared with the placebo group (P < 0.05). There were no significant treatment effects on the richness and global composition of the salivary microbiome.

HARMS: In total, one participant in the test group claimed nausea and abandoned the project. In total, two participants did not like the taste of the mouthwash but used it as instructed. No other adverse events or side effects were reported.

LIMITATIONS: Short-term pilot trials may by nature be sensitive for selection and performance biases and are not designed to unveil persisting effects.

CONCLUSION: Daily use of enzyme-containing mouthwash reduced the amount of dental biofilm in adolescents under treatment with the fixed orthodontic appliances, without affecting the composition of the salivary microbiota.

ETHICAL APPROVAL: Approved by the Regional Ethical Board, Lund, Sweden (Dnr 2020-05221).

CLINICAL TRIAL REGISTRATION: NCT05033015.

Objective: To evaluate whether retention is needed after orthodontic treatment of impacted maxillary canines.

Trial design: Two-arm parallel group single-centre randomized controlled trial.

Materials and methods: Sixty-three patients, 39 girls and 24 boys, were recruited to the study. The inclusion criteria were patients with at least one impacted or unerupted maxillary canine, and moderate irregularity of the maxillary six anterior teeth according to Little’s index (LI). After gaining informed consent from the patient and their custodians, the patients were randomized to one of two groups, i.e. to a non-retention group or a retention group. The randomization process was prepared and carried out by an independent person not involved in the trial and the randomization used blocks of 20 (10 + 10). Primary outcomes were changes in single contact point discrepancy, and LI measured on digitalized three-dimensional study casts 1-year post-treatment. The study casts were anonymized before assessment and the changes were blinded for the assessor. Data were evaluated on an intention-to-treat basis. Thus, all randomized patients were incorporated into the final analysis. In the non-retention group a 10-week interim period was used to detect patients who eventually have a relapse immediately after treatment. If so, the patient got the arch-wire reinserted. Most patients in the retention group received a vacuum-formed retainer and pretreatment spacing cases got a bonded retainer.

Results: Mean irregularity change was 0.4 mm in the retention and 1.3 mm in the non-retention group (P < 0.001). Maximum change was 2.5 mm in the retention and 3.2 mm in the non-retention group (P < 0.001). Most changes in the non-retention group occurred during the 10-week interim period. In the non-retention group, one patient developed contact point discrepancy of >2 mm during the interim period and was realigned.HarmsOne patient met the stopping guideline criteria. This patient had the arch wire reinserted for 2 months. After realignment, the patient received a retention appliance.LimitationsThe trial was a single-centre study and short-term changes were evaluated.

Conclusions: Changes between the retention and the non-retention group were statistically but not clinically significant. Since satisfactory clinical results 1-year post-treatment were found in the non-retention group, retention does not appear to be needed. The 10-week interim period was useful in detecting patients who might have a relapse immediately after treatment.

Trial registration: The trial was not registered.

Background: Retention of the maxillary anterior teeth is commonly recommended to maintain the teeth in their corrected positions. Both fixed and removable retention methods are used, but the certainty of evidence is low.

Objective: To evaluate post-treatment changes in irregularity of the maxillary six anterior teeth and single tooth contact point discrepancy (CPD) of three different retention methods.

Trial design: Three-arm parallel group single-centre randomized controlled trial.

Materials and methods: Ninety patients, 54 girls and 36 boys, were recruited to the study. The inclusion criteria were adolescent patients treated with fixed appliances at least in the maxilla. After gaining informed consent from the patient and their custodians, the patients were randomized to one of three groups: bonded retainer 13–23, bonded retainer 12–22, and removable vacuum-formed retainer (VFR) covering the maxillary teeth including the second molars. The randomization, prepared by an independent person, used blocks of 30. The primary outcomes were changes in single CPD and Little’s irregularity index (LII) measured on digitalized three-dimensional study casts before and after 2-year retention. The study casts were anonymized before assessment and the changes were blinded for the assessor. Data were evaluated on an intention-to-treat basis. Thus, all randomized patients were incorporated into the final analysis.

Results: The LII and CPDs increased slightly in all three groups without any statistically significant differences between the groups. The VFR group showed a small intercanine width increase and some more changes of canine rotations than in the other groups.

Harms: No harm was observed in any subjects and none of the patients needed retreatment.

Limitations: The trial was a single-centre study and short-term changes were evaluated.

Conclusions: All three retention methods showed equally effective retention capacity and all the changes found in the three groups were small and considered clinically insignificant. Thus, the null hypothesis was confirmed. All three methods can be recommended.

Trial registration: NCT04616755

Background: Maxillary bonded and removable retainers maintain teeth in correct positions following orthodontic treatment. There is insufficient evidence regarding the capacity of the retention methods to stabilize the maxillary teeth both during and after retention.

Objective: To evaluate retention capacity and 1-year post-retention changes in the irregularity of maxillary anterior teeth and single anterior tooth contact point discrepancy (CPD) of two bonded and one removable retention method.

Trial design: Three-arm parallel group single-centre randomized controlled trial.

Methods: Ninety adolescent patients treated with fixed orthodontic appliances were enrolled. After gaining informed consent, the patients were randomized in blocks of 30 by an independent person into one of three groups: A) bonded retainer 13-23; B) bonded retainer 12-22; and C) removable vacuum-formed retainer. The primary outcomes were changes in Little's irregularity index (LII) and single CPD measured on digitalized casts before retention (T1), after 2 years of retention (T2), and 1-year post-retention (T3).

Blinding: The digital casts were blinded for the outcome assessor.

Results: Data on all 90 patients were analysed according to intention-to-treat principles. Changes in LII during retention were 0.3 mm in group A, 0.6 mm in group B, and 1.0 mm in group C. No significant differences between the groups were seen (P > 0.05). Changes during post-retention were 1.1 mm in group A, 0.5 mm in group B, and 0.4 mm in group C. Group A showed more significant changes than groups B and C (P = 0.003). During the whole post-treatment period, no significant differences were shown between the groups (P > 0.05). CPD did not differ significantly between the groups at any point.

Harms: Three patients showed changes of LII over 3 mm or CPD over 2 mm during the post-retention period, and two accepted to be realigned.

Limitations: The trial was a single-centre study evaluating 1-year post-retention changes.

Conclusions: The changes were clinically insignificant during and after the retention period. Thus, all three methods showed equal retention capacity.

Trial registration: www.clinicaltrials.com (NCT04616755).

Syftet med arbetet var att skapa översikt av metoder och substanser för ”farmakologisk retention” efter ortodontisk behandling via injicering lokalt eller systemiskt samt undersöka kvalitén i dessa studier. Substanserna som undersöktes var Bisphosphonat, Relaxin, Bone morphogenetic protein (BMP), Anti-VEGF and Simvastatin. För den systematiska genomgången av litteraturen användes databaserna PubMed/Medline och Cochrane Library . Två personer granskade abstract utifrån inklusions/exklusionskriterier. Sökningen resulterade i 22 studier på djur. Efter inklusion/exklusion kvarstod sju studier som delades upp i lokal respektive systemisk administration. Lokal eller systemisk injicering av farmakologiska substanser visade sig minska recidiv hos försöksdjur där tänder roterats eller tippats. Underlaget är emellertid begränsat och ytterligare forskning krävs. Studier som långsiktigt undersöker substansernas effekt behövs, liksom studier på eventuell systemisk påverkan.

Det finns få studier om de små spottkörtlarna, men deras främsta funktion anses vara att skydda individen genom att utsöndra ett skyddande sekret som utgör en slags barriär mot främmande och sjukdomsframkallande substanser. Från observationer på vuxna är det känt att körtlarna producerar en rad antibakteriella ämnen, tillhörande det specifika och det ospecifika immunförsvaret. Vidare anses de små körtlarna ha en smörjande effekt, vilket troligen har stor betydelse för välbefinnandet. Inga studier av unga växande individers sekretion från små salivkörtlar tycks finnas. Studierna inriktar sig främst på att öka kunskaperna om grundläggande egenskaper hos de små salivkörtlarna och olika immunologiska faktorer i saliven från dessa körtlar. De baseras på jämförande studier mellan förskolebarn, tonåringar och yngre vuxna. Avhandlingen söker svar på följande frågeställningar: Studie I. Finns det åldersrelaterade skillnader i salivflöde från, och förekomst av, små salivkörtlar?Studie II. Finns det åldersrelaterade skillnader i mängden av framträdande ospecifika försvarskomponenter (mucinerna MUC5B och MUC7) i saliv från små körtlar? Studie III. Finns det åldersrelaterade skillnader i koncentrationen av specifika försvarskomponenter (saliv-IgA) och protein i småkörtel- och helsaliv?Studie IV. Finns det åldersrelaterade skillnader i mängden av ytterligare en viktig ospecifik försvarskomponent (Gp-340) samt mängden kolhydrater (främst sialinsyra) som företrädesvis sitter på ospecifika försvarskomponenter, i småkörtel-och helsaliven? Huvudfynden i studierna är:• Barnen hade lägre flöde från små körtlar i kindslemhinnan jämfört med de vuxna. Vidare uppvisade barnen fler körtlar i läppen jämfört med de vuxna.• Barnen och de vuxna hade samma innehåll av MUC5B, men barnen hade mindre innehåll av MUC7 i saliv från små körtlar i läppen. Endast ett fåtal individer uppvisade muciner i saliven från små körtlar i kinden.• Barnen hade lägre koncentration av saliv-IgA i saliv från små körtlar i läppen och i helsaliv, jämfört med de vuxna.• Barnen och de vuxna uppvisade liknande mängder av gp-340 och sialinsyra i småkörtelsaliven men barnen hade större mängd gp-340 i helsaliven. De vuxna hade större mängder av gp-340 och sialinsyra i saliven från små körtlar i kinden jämfört med körtlarna i läppen.Förskolebarnens småkörtelsaliv innehåller samma mängd av en rad viktiga komponenter tillhörande det ospecifika immunförsvaret som de vuxnas, medan det specifika immunförsvaret tycks fortfarande vara under utveckling hos förskolebarnen. Vidare har förskolebarnen lägre salivflöde från de små körtlarna i kinden och tätare mellan körtlarna i läppen än de vuxna. Genom denna grundläggande kunskap kan genomförandet av nya jämförande studier av hur saliven fungerar hos yngre medicinskt eller odontologiskt belastade individer och av omhändertagande av patienter med störningar i saliven utformas. Skillnader i salivsekretion mellan barn och vuxna är också viktiga att utreda bland annat som eventuell förklaringsmodell för åldersvariationer i hur orala sjukdomstillstånd mellan åldrarna uttrycks.

Purpose: The aim of this study was to assess the artefacts of 12 fixed orthodontic appliances in magnetic resonance images obtained using 1.5-T and 3-T scanners, and to evaluate different imaging sequences designed to suppress metal artefacts. Materials and Methods: In vitro, study casts of 1 adult with normal occlusion were used. Twelve orthodontic appliances were attached to the study casts and scanned. Turbo spin echo (TSE), TSE with high readout bandwidth, and TSE with view angle tilting and slice encoding for metal artefact correction were used to suppress metal artefacts. Artefacts were measured. In vivo, 6 appliances were scanned: 1) conventional stainless-steel brackets; 2) nickelfree brackets; 3) titanium brackets; 4) a Herbst appliance; 5) a fixed retainer; and 6) a rapid maxillary expander. The maxilla, mandible, nasopharynx, tongue, temporomandibular joints, and cranial base/eye globes were assessed. Scores of 0, 1, 2, and 3 indicated no artefacts and minor, moderate, and major artefacts, respectively. Results: In vitro, titanium brackets and the fixed retainer created minor artefacts. In vivo, titanium brackets caused minor artefacts. Conventional stainless-steel and nickel free brackets, the fixed retainer, and the rapid maxillary expander caused major artefacts in the maxilla and mandible. Conventional stainless-steel and nickel-free brackets caused major artefacts in the eye globe (3-T). TSE with high readout bandwidth reduced image artefacts in both scanners. Conclusion: Titanium brackets, the Herbst appliance, and the fixed retainer caused minor artefacts in images of neurocranial structures (1.5-T and 3-T) when using TSE with high readout bandwidth.

Background/objectives: The management of post-orthodontic white spot lesions is based on remineralization strategies or a minimal-invasive camouflage of the lesions. Aim: The aim of this systematic review was to identify and assess the quality of evidence for the various clinical technologies. Search methods: Four databases were searched for relevant literature published in English between 2011 and October 31 2015 according to a pre-determined PICO. Only controlled clinical studies were considered. Abstract lists and the selected full-text papers were independently examined by two reviewers and any differences were solved in consensus. The Cochrane handbook and the AMSTAR tool were used for grading the risk of bias. The quality of evidence was rated according to GRADE. Results: Out of 280 identified publications, 7 studies on remineralization, micro-abrasion and resin infiltration met the inclusion criteria. Two of them were assessed with low risk of bias. No pooling of results was possible due to study heterogeneity. The quality of evidence for all technologies was graded as very low. Limitations: Only papers published in English with more than 20 adolescents or young adults were considered. Furthermore, a follow-up period of at least 8 weeks was required. The publication bias could not be assessed due to the paucity of included trials. Conclusions/clinical implications: There is a lack of reliable scientific evidence to support re-mineralizing or camouflaging strategies to manage post-orthodontic white spot lesions. Further well-performed controlled clinical trials with long-term follow-up are needed to establish best clinical practice.

Background: Self-applied and professional fluorides are key elements to limit caries-related side-effects during orthodontic treatment with fixed appliances.

Objective: To evaluate the effectiveness of a new fluoride varnish formula containing 1.5% ammonium fluoride in preventing white spot lesions (WSLs) in adolescents undergoing multi-bracket orthodontic treatment.

Subjects and methods: The study employed a randomized controlled triple-blinded design with two parallel arms. One hundred eighty-two healthy adolescents (12-18 years) referred to three orthodontic specialist clinics were eligible and consecutively enrolled. Informed consent was obtained from 166 patients and they were randomly allocated to a test or a placebo group (with aid of a computer program, generating sequence numbers in blocks of 15). In the test group, fluoride varnish was applied in a thin layer around the bracket base every sixth week during the orthodontic treatment, while patients in the placebo group received a varnish without fluoride. The intervention started at onset of the fixed appliances and continued until debonding. The endpoint was prevalence and severity of WSLs on the labial surfaces of the maxillary incisors, canines, and premolars as scored from high-resolution pre- and post-treatment digital photos with aid of a four-level score.

Results: One hundred forty-eight patients completed the trial, 75 in the test group and 73 in the placebo group (dropout rate 10.8%). The total prevalence of WSL's on subject level after debonding was 41.8% in the test group and 43.8% in the placebo group. The number of patients exhibiting more severe lesions (score 3 + 4) was higher in the placebo group (P < 0.05); the absolute risk reduction was 14% and the number needed to treat was 7.1.

Limitations: The multicentre design with somewhat diverging routines at the different clinics may have increased risk for performance bias. No health-economic evaluation was carried out.

Conclusions: Regular applications of an ammonium fluoride varnish reduced the prevalence of advanced WSL during treatment with fixed orthodontic appliances.

Clinical trial registration: ClinicalTrials.gov (NCT03725020).

Protocol: The protocol was not published before trial commencement.

BACKGROUND: Topical fluorides are commonly recommended to prevent the development of white spot lesion (WSL) during treatment with fixed orthodontic appliances (FOAs), but the certainty of evidence is low, and long-term effects of fluoride preventive methods to reduce lesions seem to be rare.

OBJECTIVE: To evaluate the long-term effectiveness of professional applications of a fluoride varnish containing 1.5% ammonium fluoride in preventing WSL development in adolescents undergoing multi-bracket orthodontic treatment.

SUBJECTS AND METHODS: We performed a randomized controlled trial in which 166 healthy adolescents (12-18 years) from three different clinics were enrolled and randomly allocated to a test or a placebo group. The randomization was performed by a computer program, generating sequence numbers in blocks of 15. The fluoride varnish or the non-fluoride placebo varnish was applied in a thin layer around the bracket base every sixth week during the course of the orthodontic treatment (mean duration 1.7 years). We scored the prevalence of WSL on the labial surfaces of the maxillary incisors, canines and premolars immediately after debonding (baseline) and approximately 1 year after debonding, from digital photos with aid of a four-step score. The examiners were not involved in the treatment of the patients and blinded for the group assignment.

RESULTS: One hundred and forty-eight patients were available at debonding and 142 of them could be re-examined after 1 year (71 in the test and 71 in the placebo group). The 1-year attrition rate was 4.0%. On patient level, the prevalence of post-orthodontic WSLs (score ≥ 2) dropped by over 50% during the follow-up with no significant difference between the groups. On surface level, there were significantly fewer remaining WSLs in the test group compared with the placebo group (4.5% versus 10.4%; relative risk 0.44, 95% confidence interval 0.28-0.68).

LIMITATIONS: The compliance with fluoride toothpaste was not checked, and the patients' general dentists may have instigated additional risk-based preventive measures. No cost-benefit analysis was carried out.

CONCLUSIONS: This follow-up study displayed a small beneficial long-term effect of fluoride varnish in reducing WSL development during treatment with FOA.

REGISTRATION: NCT03725020.

PROTOCOL: The protocol was not published before trial commencement.

Background: Recently low-level laser therapy (LLLT) has been proposed to improve orthodontic treatment. The aims of this systematic review were to investigate the scientific evidence to support applications of LLLT: (a) to accelerate tooth movement, (b) to prevent orthodontic relapse and (c) to modulate acute pain, during treatment with fixed appliances in children and young adults. Methods: To ensure a systematic literature approach, this systematic review was conducted to Goodman's four step model. Three databases were searched (Medline, Cochrane Controlled Clinical Trials Register and Scitation), using predetermined search terms. The quality of evidence was rated according to the GRADE system Results: The search identified 244 articles, 16 of which fulfilled the inclusion criteria: three on acceleration of tooth movement by LLLT and 13 on LLLT modulation of acute pain. No study on LLLT for prevention of relapse was identified. The selected studies reported promising results for LLLT; elevated acceleration of tooth movement and lower pain scores, than controls. With respect to method, there were wide variations in type of laser techniques Conclusions: The quality of evidence supporting LLLT to accelerate orthodontic tooth movement is very low and low with respect to modulate acute pain. No studies met the inclusion criteria for evaluating LLLT to limit relapse. The results highlight the need for high quality research, with consistency in study design, to determine whether LLLT can enhance fixed appliance treatment in children and young adults.

The minor salivary glands are of great importance in the physiology and pathology of the oral cavity. So far, studies of the minor glands have concentrated on adults. In the present study, minor salivary gland secretion was studied in the buccal and labial mucosa of 3-year-old children, adolescents and young adults. In addition, the number of glands per surface area was assessed in the labial mucosa. A total of 90 individuals were included, 30 in each age-group. Saliva was collected on filter paper discs and the salivary secretion rate was measured using a Periotron 8000. The number of secreting labial glands was assessed on PAS-stained filter paper discs under a microscope. Salivary secretion in the buccal mucosa was found to be age-related, with a statistically significant lower rate of secretion (P=0.003) in the 3-year-olds (mean 7.7 microl x cm(-2) x min(-1)) compared with the young adults (11.9 microl x cm(-2) x min(-1)). No significant differences between the sexes were noted. For the labial glands, no age- or sex-related differences were found. In all age-groups, salivary secretion was significantly higher in the buccal than in the labial mucosal area. A statistically significant difference in number of secreting glands was found between all age-groups, with a decreasing number of glands per surface unit with age. The number of glands was significantly lower in males compared with females in the group of adults. The lower rate of buccal salivary secretion in the young children may imply that the oral mucosa is more vulnerable to external injury and that caries protection on the buccal molar surfaces is lower. Previous studies indicate that adults with a reduced rate of minor salivary gland secretion are more susceptible to caries.

Glycoprotein 340 (gp-340) is a bacterial-binding glycoprotein observed in major and minor gland saliva. Sialic acid, a common terminal structure of salivary glycoproteins, interacts with microorganisms and host ligands, as well as free radicals. This study investigated the content of gp-340 and sialic acid in minor gland and whole saliva of children (3-yr-olds), adolescents (14-yr-olds) and adults (20 to 25-yr-olds). Labial and buccal gland saliva was collected on filter paper and un-stimulated whole saliva by draining into a tube. The relative amount of gp-340 and sialic acid was determined by ELISA and ELLA, respectively. In minor gland saliva, no statistically significant differences in gp-340 and sialic acid were seen between the age-groups. Significantly lower amounts of gp-340 and sialic acid were seen in labial saliva compared to buccal among adults (P < 0.05, P < 0.01). In whole saliva, the amount of gp-340 was significantly lower among adults compared to children (P < 0.01). No differences between genders were seen. Stable gp-340 and sialic acid contents in minor-gland saliva across the age-groups and higher gp-340 content in the whole saliva of the youngest age-group (3-yr-olds) compared with the adult-group may reflect a vital innate factor of immunity in children’s saliva.

Immunoglobulin A (IgA) is the principal immunoglobulin in human saliva and minor salivary glands contribute with approximately 30-35 % of the total salivary IgA in whole saliva. Salivary IgA is considered to be a vital component of the defence of the oral tissues and the concentration seems to increase with age. However, data on the salivary IgA-concentration in minor gland saliva of children, compared to adults, is not available. Objectives: To study the salivary IgA-concentration in minor gland saliva in defined mucosal areas, and in un-stimulated whole saliva, in children in different ages and young adults. Methods: 90 individuals were recruited: 3-year-old children (n = 30), 14-year-old children (n = 30), and young adults (n = 30). Minor gland saliva was collected on labial and buccal mucosa with filter papers and the volume was determined using a Periotron 8000. The whole saliva was collected by draining into a tube. Assessment of the salivary IgA-concentration was carried out in a sandwich ELISA. One-way ANOVA was used testing the differences between the age-groups (at the 0.05 level of significance). Results: The salivary IgA-concentration in labial gland saliva was significantly lower (p<0.05) in the 3-year-olds (3.7 mg/100 ml +/- 3.5) compared with the 14-year-olds (12.6 mg/100ml +/- 12.8) and the adults (12.8 mg/100ml +/- 13.4). In the un-stimulated whole saliva, a significantly lower salivary IgA-concentration was noted for the youngest group (9.0 mg/100ml +/-9.1) compared with the 14-year-olds (17.9 mg/100ml +/-14.9) and the adults (17.0 mg/100ml +/-9.9). Conclusion: The salivary IgA-concentration in labial and un-stimulated whole saliva seems to increase with age. This may reflect a developing specific immune response in saliva of young children. Approved by the ethical committee, Lund University. Funded by The Crafoord foundation (20090733), Swedish Patent Revenue Foundation and Faculty of Odontology, Malmö University (OD27-2009/275).

According to previous studies, minor glands produce about 35% of the total salivary immunoglobulin A (salivary IgA). The age-dependent increase in whole-saliva salivary IgA concentrations has been studied extensively, but we found no published reports comparing the minor-gland saliva concentrations of salivary IgA in children, adolescents, and adults. In this study we measured the concentration of salivary IgA in saliva from the labial and the buccal minor glands of children, adolescents, and adults. Three age groups donated saliva for analysis: 3-yr-old children, 14-yr-old adolescents, and 20- to 25-yr-old adults. Minor-gland saliva was collected on filter paper and unstimulated whole saliva was collected by draining into a tube, and the salivary IgA concentration was determined by ELISA. The salivary IgA concentration in labial saliva was significantly lower among 3-yr-old children (0.037 mg 100 ml(-1), SD = 0.035) than among 14-yr-old adolescents (0.126 mg 100 ml(-1), SD = 0.128) and adults (0.128 mg 100 ml(-1), SD = 0.13). The 3-yr-old children also had significantly lower whole-saliva salivary IgA values compared with the other age groups (0.09 mg 100 ml(-1), SD = 0.091; 0.179 mg 100 ml(-1), SD = 0.149; and 0.170 mg 100 ml(-1), SD = 0.099, respectively). This increase in salivary IgA concentrations with age might reflect a developing immune response in the growing child.

This study determined the concentration of salivary immunoglobulin A (salivary IgA) in saliva from labial and buccal minor glands of children, adolescents, and adults. According to previous studies minor glands produce about 35% of total salivary IgA. Age-dependent increase in whole-saliva salivary IgA concentrations has been studied extensively, but we found no reports comparing minor-gland saliva concentrations of salivary IgA in children, adolescents, and adults. Three age groups donated saliva for analysis: 3-yr-olds (n = 28), 14-yr-olds (n = 27), and 20 to 25-yr-olds (n = 26). Minor-gland saliva was collected on filter paper and unstimulated whole saliva by draining into a tube and salivary IgA concentration was determined by ELISA. Salivary IgA concentration in labial saliva was significantly lower (P < 0.01) among 3-yr-olds (3.7 mg 100 ml-1, SD 3.5) compared to 14-yr-olds (12.6 mg 100ml-1, SD 12.8) and adults (12.8 mg 100ml-1, SD 13.4). The 3-yr-olds also had significantly lower (P < 0.05) whole-saliva salivary IgA values compared to the other age groups (9.0 mg 100ml-1, SD 9.1; 17.9 mg 100ml-1, SD 14.9; and 17.0 mg 100ml-1, SD 9.9, respectively). This increase in salivary IgA concentrations with age might reflect a developing immune response in the growing child

Apical Root Resorption (ARR) of the maxillary incisors is an adverse effect in patients during treatment with orthodontic appliance. Limited number of prospective investigations on ARR in patients with Removable Orthodontic Appliance (ROA) is available and the reliability of assessments of ARR in periapical radiographs has not been evaluated. The aims were to investigate 1) Observer agreement regarding assessment of ARR in radiographs obtained during treatment with ROA in children and 2) The extent and severity of ARR in children during treatment with ROA. Material and Methods One hundred ten children, with Angle class II malocclusion or anterior cross bite suitable for treatment with ROA were consecutively recruited. Periapical radiographs of maxillary incisors were obtained before (T0) and after six month of treatment (T1). The contour of the roots was scored as 0, 1, 2, 3 or 4 according to a modified Levander and Malmgren index, by five observers. Score 0 represent normal root contour, score 4 severe root resorption. Inter- and intra-observer agreement was calculated as overall agreement and kappa values. Results In the 110 patients, 49 females, 61 males, the mean age was 10.6 years. Totally 439 roots were available for assessment. Kappa values for pair wise inter-observer agreement during treatment ranged between -0.01 and 0.27. Kappa values for intra-observer agreement ranged between -0.09 and 0.45 before treatment and -0.22 and 0.48 after treatment. Conclusion Reliability in assessing root morphology/resorption in periapical radiographs obtained in children during treatment with removable appliance is low. ARR seems to be of minor extent, however, the low reliability indicates difficulties in evaluating the severity and thereby the clinical importance in this young patient group.

BACKGROUND: There has been an increased interest in conducting healthcare economic evaluations. Also, orthodontic treatments have gathered focus from an economic point of view, however orthodontic research seldom examines both clinical and economic outcomes.

OBJECTIVE: To evaluate and compare the costs of three retention methods: a bonded retainer to the maxillary four incisors, a bonded retainer to the maxillary four incisors and canines, and a removable vacuum-formed retainer (VFR) in the maxilla. The null hypothesis was that there was no difference in costs for the three types of retention methods.

TRIAL DESIGN: Three-arm, parallel group, single-centre, randomized controlled trial.

MATERIALS AND METHODS: Ninety adolescent patients, 54 girls and 36 boys, treated with fixed or removable retainers in the maxilla, were recruited to the study. The patients were randomized in blocks of 30, by an independent person, to one of three groups: bonded multistranded PentaOne (Masel Orthodontics) retainer 13-23, bonded multistranded PentaOne (Masel Orthodontics) retainer 12-22, and removable VFR. A cost analysis was made regarding chair time costs based on the costs per hour for the specialist in orthodontics, and material costs plus any eventual costs for repairs of the appliance. Changes in Little's irregularity index and in single contact point discrepancies (CPDs) were measured on digitalized three-dimensional study casts. Data were evaluated on an intention-to-treat basis. The analysis was performed at 2 years of retention.

RESULTS: No statistically significant difference in costs between the maxillary fixed retainers and the VFRs was found, however, the material and emergency costs were significantly higher for the VFR compared with the bonded retainers. All three retention methods showed equally effective retention capacity, and no statistically significant differences in irregularity or CPDs of the maxillary anterior teeth in the three groups was detected.

LIMITATIONS: It was a single-centre trial, and hence less generalizable. Costs depended on local factors, and consequently, cannot be directly transferred to other settings.

CONCLUSIONS: All three retention methods can be recommended when considering costs and retention capacity.

TRIAL REGISTRATION: NCT04616755.

Objectives: Approximately 25% of the adolescents in the Scandinavian population are treated with a fixed orthodontic appliance (FOA). Adverse effects such as enamel decalcification (white spot lesions - WSL), seem to affect over 30% of patients. WSL have only a limited ability to improve, thus seriously jeopardising the treatment outcome. The aim of present study was to explore the biofilm phenotype by investigating plaque collected: 1) adjacent to brackets, and 2) in gingival margin of maxillary incisors in adolescents with FOA. Incidence of WSL after treatment was also assessed. Design: In eight adolescent patients treated with FOA, supra-gingival plaque formed on: 1) brackets, and 2) along the gingival margin of the maxillary incisors, was collected after 6-8 months of treatment. The patients were documented before and after treatment by intraoral photos. Plaque samples were tested for glycosidase(fluorogenic substrates) and protease (FITC-labelled casein substrate) activities. The plaque samples were visualised by Live/Dead BacLight stain, following which cells were investigated by confocal scanning laser microscopy. Results: In the collected plaque samples, all enzymes tested displayed small variations in activity between the individuals, except glucosidases, which varied significantly. Four patients developed WSL. The patients displayed higher glucosidase activity in plaque of brackets compared to patients without WSL. In seven patients, plaque at the gingival margin displayed higher protease activity than plaque of brackets. Conclusions: The current study shows two distinct environmentally induced biofilm phenotypes: 1) brackets with higher glucosidase activity, and 2) gingival margin with higher protease activity. Glucosidase activity might thus be used as a putative biomarker for risk of WSL.

BACKGROUND: Fluoride varnish (FV) is an established technology for primary and secondary caries prevention.

OBJECTIVE: The aim of this review was to evaluate the preventive effect of FV on development of white spot lesions (WSL) when regularly applied during orthodontic treatment with fixed appliances.

SEARCH METHODS: We searched PubMed, Scopus and Google Scholar up to October 2022 using predetermined keywords.

SELECTION CRITERIA: We included randomized controlled trials of a duration of minimum 12 months and at least quarterly FV applications.

DATA COLLECTION AND ANALYSIS: Based on abstracts, we retrieved full-text papers, extracted key outcome data, and assessed risk of bias. Primary outcome was prevalence of WSLs on subject level after debonding. We conducted a narrative synthesis and pooled comparable outcome data in a random effects model.

RESULTS: We included seven studies covering 666 patients and assessed four publications with low or moderate risk of bias and three with high. The prevalence of WSLs at debonding varied between 12 and 55%. All studies presented results in favour for the FV intervention, one reached statistical significance on subject level. Five studies provided data for a meta-analysis. The pooled risk ratio was 0.64 [95% CI: 0.42, 0.98], indicating a statistically significant preventive effect. Certainty of evidence was graded as very low after reducing for risk of bias, inconsistency and imprecision.

LIMITATIONS: We pooled data on subject level and did not consider lesion severity on tooth level.

CONCLUSIONS AND IMPLICATIONS: Even if the certainty of evidence was very low, it was shown that FV can prevent development of WSL when regularly applied during orthodontic treatment. Larger investigations reporting a core outcome set are required to increase the certainty of evidence.

REGISTRATION: PROSPERO database (CRD42022370062).

OBJECTIVE: To evaluate the effectiveness of daily tooth brushing with high-fluoride toothpaste on white spot lesion (WSL) formation in adolescents during treatment with fixed orthodontic appliances (FOA). Materials and Methods: Four hundred and twenty-four healthy 11- to 16-year-old patients, referred to five Orthodontic Specialist Clinics, were randomized to use either toothpaste containing 5000 ppm fluoride or regular toothpaste with 1450 ppm fluoride. To be eligible for inclusion, the patients had to be scheduled for bimaxillary treatment with FOA for an expected duration of at least 1 year. The primary and secondary outcome measures were prevalence and incidence of WSL, as registered from digital photos of the maxillary incisors, canines, and premolars taken before onset and immediately after debonding. The photos were evaluated separately by two blinded and calibrated clinicians using a 4-step score. A random sample of 50 cases was reassessed to check intra- and interexaminer reliability (Kappa = 0.70; 0.74). Results : The use of high-fluoride toothpaste resulted in fewer WSL (P = 0.042) with a prevented fraction of 32%. The lateral incisor was most commonly affected in both groups. Conclusion: To prevent WSL during treatment of FOA, daily use of high-fluoride toothpaste may be recommended.

OBJECTIVE: The study was designed to investigate the relative amount of MUC5B and MUC7 in minor salivary glands in children and adults, in order to test the hypothesis that secretion of salivary mucins changes between childhood and adulthood. METHODS: Ninety individuals in the age-groups 3-year-olds, 14-year-olds, and young adults 20-25 year-olds were recruited. Sialopapers were applied on the labial and the buccal mucosa and then placed in the Periotron 8000 (Proflowtrade mark) for calculation of the amount of saliva. The assessment of MUC5B and MUC7 was carried out in an ELISA using the LUM5B-2 and the LUM7-1 antiserum, respectively. RESULTS: MUC5B and MUC7 were detected in the labial minor gland saliva in all age groups. In buccal gland saliva, only a few individuals in each age group showed detectable amounts of the mucins. In the labial area, a significantly lower level of MUC7 was noted in 3-year-olds compared with adults. CONCLUSION: The results indicate a site-dependent difference in minor gland mucin secretion and an age-related difference in the labial gland secretion of MUC7.