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Objective To identify and determine the relationship between facial, maxillary arch and incisor dimensions of patients presenting with a unilaterally impacted palatal canine. Methods Prospective referrals over one calendar year of patients identified with a unilaterally impacted palatal canine were compared with prospectively recruited control subjects. Canine location was determined radiographically and re-confirmed two weeks later. Facial, maxillary arch and incisor dimensions were assessed. Intra-examiner reproducibility was re-assessed using randomly selected images (20%, n = 40). General linear models were applied for inter-group comparisons incorporating Bonferroni adjustment with categorical parameters assessed using Fisher’s exact test (SAS®, Version 9.4, SAS.com). Inter-class correlation coefficients were calculated for relationships between the variables. Results Fifty-four patients (37 females; 17 males) presenting with a unilaterally impacted palatal canine [mean age 14.5 (SD 1.7) years] and 54 control subjects (37 females, 17 males) [mean age 14.3 (SD 2.2) years] were recruited. Measurement error was small for landmark data (0.58 mm), palatal depth (0.09 mm), palatal area (0.42 mm²) and Bolton ratio (0.14%). For facial, maxillary arch and tooth shape assessments, landmark error was 0.05 mm with complete agreement for classification. The mean nasal basal width was smaller in the unilaterally impacted palatal canine group compared with the control group (P P > 0.05). The mean anterior Bolton ratio was larger in the impacted canine group (P P > 0.05). No positive correlations were identified between the variables. Conclusions Patients with a unilaterally impacted palatal canine had a narrower mean nasal basal width and a larger mean anterior Bolton ratio compared to a control group but the clinical significance of the differences was considered minor. Facial, maxillary arch and incisor dimensions were neither individually nor collectively correlated with a palatal canine which may lend support to a genetic aetiology.

The twin-block appliance is a widely used functional appliance for the correction of Class II division 1 malocclusion in growing children and adolescents. This article outlines the indications and case assessment, the steps in clinical management and appliance design. Evidence regarding the mode of action, effects and prediction of treatment outcome of the twin-block appliance for Class II division 1 malocclusion are also presented. CPD/Clinical Relevance: The twin-block appliance is a widely used functional appliance in the UK for the correction of Class II division 1 malocclusion in growing children and adolescents.

Retaining teeth in their corrected positions following orthodontic treatment is one of the most challenging aspects of orthodontic practice. Despite much research, the rationale for retention is not entirely clear. Teeth tend to revert to their pre-treatment positions due to periodontal and gingival, soft tissue, occlusal and growth factors. Changes may also follow normal dentofacial ageing and are unpredictable with great variability. In this overview, each of these factors are discussed with their implications for retention, along with adjunctive procedures to minimise relapse. The state of current knowledge, methods used to assess relapse, factors regarded as predictive of or associated with stability as well as overcorrection are outlined. Potential areas requiring further investigation are suggested. The way in which the clinician may manage current retention practice, with a need for individualised retention plans and selective retainer wear, is also considered.

Indefinite retention is now considered essential to prevent relapse after orthodontic treatment. Compliance with removable retainer wear is suboptimal and appears to decline with time post-treatment. As a result, use of bonded retainers may become more commonplace in the future. In this narrative review, the characteristics of bonded retainers are outlined and a summary of the evidence from randomized clinical trials regarding their effectiveness is provided. Guidance is also offered regarding care and maintenance. CPD/Clinical Relevance: All general dental practitioners (GDPs) should be familiar with types of bonded retainers, evidence relating to their effectiveness and the GDP's role regarding their care and maintenance.

BACKGROUND: Crowded teeth develop when there is not enough space in the jaws into which the teeth can erupt. Crowding can affect baby teeth (deciduous dentititon), adult teeth (permanent dentition), or both, and is a common reason for referral to an orthodontist. Crowded teeth can affect a child's self‐esteem and quality of life. Early loss of baby teeth as a result of tooth decay or trauma, can lead to crowded permanent teeth. Crowding tends to increase with age, especially in the lower jaw. OBJECTIVES: To assess the effects of orthodontic intervention for preventing or correcting crowded teeth in children. To test the null hypothesis that there are no differences in outcomes between different orthodontic interventions for preventing or correcting crowded teeth in children. SEARCH METHODS: Cochrane Oral Health's Information Specialist searched four bibliographic databases up to 11 January 2021 and used additional search methods to identify published, unpublished and ongoing studies. SELECTION CRITERIA: We included randomised controlled trials (RCTs) that evaluated any active interventions to prevent or correct dental crowding in children and adolescents, such as orthodontic braces or extractions, compared to no or delayed treatment, placebo treatment or another active intervention. The studies had to include at least 80% of participants aged 16 years and under. DATA COLLECTION AND ANALYSIS: Two review authors, independently and in duplicate, extracted information regarding methods, participants, interventions, outcomes, harms and results. We resolved any disagreements by liaising with a third review author. We used the Cochrane risk of bias tool to assess the risk of bias in the studies. We calculated mean differences (MDs) with 95% confidence intervals (CI) for continuous data and odds ratios (ORs) with 95% CIs for dichotomous data. We undertook meta‐analysis when studies of similar comparisons reported comparable outcome measures, using the random‐effects model. We used the I(2) statistic as a measure of statistical heterogeneity. MAIN RESULTS: Our search identified 24 RCTs that included 1512 participants, 1314 of whom were included in analyses. We assessed 23 studies as being at high risk of bias and one as unclear. The studies investigated 17 comparisons. Twenty studies evaluated fixed appliances and auxiliaries (lower lingual arch, lower lip bumper, brackets, archwires, lacebacks, headgear and adjunctive vibrational appliances); two studies evaluated removable appliances and auxiliaries (Schwarz appliance, eruption guidance appliance); and two studies evaluated dental extractions (lower deciduous canines or third molars). The evidence should be interpreted cautiously as it is of very low certainty. Most interventions were evaluated by a single study. Fixed appliances and auxiliaries One study found that use of a lip bumper may reduce crowding in the early permanent dentition (MD −4.39 mm, 95% CI −5.07 to −3.71; 34 participants). One study evaluated lower lingual arch but did not measure amount of crowding. One study concluded that coaxial nickel‐titanium (NiTi) archwires may cause more tooth movement in the lower arch than single‐stranded NiTi archwires (MD 6.77 mm, 95% CI 5.55 to 7.99; 24 participants). Another study, comparing copper NiTi versus NiTi archwires, found NiTi to be more effective for reducing crowding (MD 0.49 mm, 95% CI 0.35 to 0.63, 66 participants). Single studies did not show evidence of one type of archwire being better than another for Titinol versus Nitinol; nickel‐titanium versus stainless steel or multistrand stainless steel; and multistranded stainless steel versus stainless steel. Nor did single studies find evidence of a difference in amount of crowding between self‐ligating and conventional brackets, active and passive self‐ligating brackets, lacebacks added to fixed appliances versus fixed appliances alone, or cervical pull headgear versus minor interceptive procedures. Meta‐analysis of two studies showed no evidence that adding vibrational appliances to fixed appliances reduces crowding at 8 to 10 weeks (MD 0.24 mm, 95% CI −0.81 to 1.30; 119 participants). Removable appliances and auxiliaries One study found use of the Schwarz appliance may be effective at treating dental crowding in the lower arch (MD ‐2.14 mm, 95% CI −2.79 to −1.49; 28 participants). Another study found an eruption guidance appliance may reduce the number of children with crowded teeth after one year of treatment (OR 0.19, 95% CI 0.05 to 0.68; 46 participants); however, this may have been due to an increase in lower incisor proclination in the treated group. Whether these gains were maintained in the longer term was not assessed. Dental extractions One study found that extracting children's lower deciduous canines had more effect on crowding after one year than no treatment (MD −4.76 mm, 95 CI −6.24 to −3.28; 83 participants), but this was alongside a reduction in arch length. One study found that extracting wisdom teeth did not seem to reduce crowding any more than leaving them in the mouth (MD −0.30 mm, 95% CI −1.30 to 0.70; 77 participants). AUTHORS' CONCLUSIONS: Most interventions were assessed by single, small studies. We found very low‐certainty evidence that lip bumper, used in the mixed dentition, may be effective for preventing crowding in the early permanent dentition, and a Schwarz appliance may reduce crowding in the lower arch. We also found very low‐certainty evidence that coaxial NiTi may be better at reducing crowding than single‐stranded NiTi, and that NiTi may be better than copper NiTi. As the current evidence is of very low certainty, our findings may change with future research.

Objective: To compare Phase 1 treatment, using the Frankel 2 (FR2) or the modified Twin Block (MTB), for Class II division 1 malocclusion in children and adolescents with respect to: treatment duration, number of appliance breakages, occlusal outcome, and patient and parent perspectives. Materials and Methods: Sixty participants with a Class II division 1 malocclusion were randomly assigned to either the FR2 or MTB appliance in a two-armed parallel randomized clinical trial with an allocation ratio of 1 to 1. Time to achieve a Class I incisor relationship was the primary outcome. The number of appliance breakages was recorded. The Peer Assessment Rating (PAR) index was used to evaluate pre- and post-treatment occlusal outcome on study models. Participants completed the child OHRQoL (oral health-related quality of life), Piers-Harris, Standard Continuum of Aesthetic Need (SCAN), and Oral Aesthetic Subjective Impact Score (OASIS) questionnaires pre- and post-treatment; parents completed a SCAN questionnaire. Results: Forty-two participants completed treatment (FR2: 20; MTB: 22). Multiple imputation was used to impute missing data for noncompleters. Mean treatment duration was similar for the two appliances (FR2: 376 days [SD 101]; MTB: 340 days [SD 102]; P = .41). There were no significant differences in mean number of appliance breakages (FR2: 0.3 SD 0.7; MTB: 0.4 SD 0.8; P = .67 or mean PAR score P = .48). Patient and parent perspectives did not differ between appliances (P > .05). Conclusions: Phase 1 treatment duration, number of appliance breakages, occlusal outcome, and patient and parent perspectives were similar in 11–14 year olds with Class II division 1 malocclusion treated using the FR2 or MTB appliance.

OBJECTIVE: To obtain the opinion of British Orthodontic Society (BOS) members in relation to possible patterns of prescription of orthodontic extractions over the past 5-10 years and to relate any changes identified to treatment objectives, facial and smile aesthetics, and treatment strategies and adjuncts. DESIGN: Cross-sectional questionnaire. SETTING: On-line survey of BOS members. METHODS: A 14-item on-line questionnaire was sent to orthodontic practitioners for completion. The questionnaire covered demographics, possible changes in frequency of prescribed extractions with specific information concerning the effect of patient age, and the influence of other factors including alternative approaches to space creation, evolving treatment mechanics, smile and facial aesthetics, and retention protocols. RESULTS: Two hundred and eight responses were obtained with 95.6% (n = 199) reporting reduced extraction prescription over the last 5-10 years. Overall, 29.9% and 35.5% felt that their threshold for extractions had increased by more than 2 mm in adolescents and adults, respectively. Facial (n = 145; 69.7%) and smile (n = 127; 61.1%) aesthetics, and increased use of inter-proximal reduction (n = 102; 49%) were the factors most frequently reported as having either a moderate or major influence on this trend. Based on ordinal logistical regression analyses, no significant relationship was found between threshold for extractions and work setting (P = 0.675; O.R. 0.51; 95% CI: 0.39, 1.85) or level of orthodontic experience (P = 0.15; O.R. 1.02; 95% CI: 0.15, 1.05), although a higher threshold for extractions was more likely among users of conventional than self-ligating brackets (P = 0.001; O.R. 4.74; 95% CI: 1.95, 11.5). CONCLUSIONS: A reduced tendency to prescribe orthodontic extractions over the past 5-10 years among British Orthodontic Society members was identified. Comparative clinical research exploring the relative merits of extraction and non-extraction approaches could be timely.

Background/aims Mild resting facial asymmetry exists in clinically symmetrical faces, but the effect of smiling on the magnitude of overall facial asymmetry in adults has not been assessed. The aim of the present study was to use stereophotogrammetry to quantify the effect of smiling on overall facial asymmetry in Caucasian adults who presented with Class I incisor relationships and no history of orthodontic treatment. Methods Twenty male and 20 female Caucasians aged 18–30 years with no history of orthodontic treatment, a clinically symmetrical face and a Class I incisor relationship had 3D stereophotogrammetric images captured at rest and on natural and maximal smile (T1). The images were repeated 2–4 weeks later (T2) to assess expression reproducibility. Overall facial asymmetry scores were produced from 27 landmarks using partial Ordinary Procrustes Analysis (OPA) and assessed by an Analysis of Covariance (ANCOVA) model. A random sample of the images was re-examined two months later to calculate intraobserver landmark reproducibility. Results Mean landmark error was low (0.41 ± 0.07 mm). Mean overall facial asymmetry scores were not significantly gender different (p = 0.5300); therefore, the male and female data were pooled. Mean overall facial asymmetry scores for maximal (0.91 ± 0.16) and natural smile (0.88 ± 0.18) were higher than at rest (0.80 ± 0.17) (p < 0.0001) and were reproducible across (T1–T2) sessions (p = 0.3204). Conclusions/implications Overall 3D facial asymmetry scores for the sampled Caucasian adults with clinically symmetrical faces increased in magnitude from rest to natural and to maximal smile. Clinicians should assess overall facial asymmetry at rest and on natural and maximal smile at baseline, during treatment and as part of a core outcome assessment, particularly for cases with unilateral posterior crossbite, unilateral cleft lip and palate or skeletal asymmetry.

To report the opinions of specialist orthodontists regarding the profile, characteristics and treatment of adults currently undergoing orthodontic treatment in the Republic of Ireland (ROI) Design/setting: A national cross-sectional questionnaire study in the ROI.A pilot-tested questionnaire was distributed to 122 specialist orthodontists in the ROI. Questions addressed general and treatment information for current adult orthodontic patients. Those whose treatment involved orthognathic surgery were not excluded.A response of 83% was obtained. Ninety-five per cent of specialists reported treating adults, most of whom were self-referred and were typically professional, female and aged 25-35 years. The overall ratio quoted of professionals to non-professionals was almost 3:2. For 50% of specialists, males were estimated to account for 20-40% of their adult cases and for 23%, this increased to an estimated 40-60%. Class II division 1 malocclusion and skeletal II were considered the most common dentofacial characteristics. Occlusal features encountered in decreasing frequency were generalised crowding, increased overjet, deep overbite, late lower incisor crowding, spacing and impacted teeth. Fifteen per cent reported that at least 10% of their adult cases required orthodontics with maxillofacial surgery but 8% reported that this was at least 50%. Treatment challenges commonly acknowledged were overbite reduction, anchorage management, 'black triangles' and overjet reduction. Tooth whitening was reckoned to be used by 19% of specialists. Aesthetic upper and stainless steel lower brackets were indicated to be used most often whereas only 19% used clear aligners and 10% used lingual appliances often.The profile and characteristics of adults currently undergoing orthodontic treatment in the ROI were diverse. Higher estimates were quoted for self- than for general dental practitioner-referral. A high percentage of treatment was reported to be undertaken for non-professionals and males. A wide range of treatment and varying use of appliance types were cited.

Background\ud \ud Early dental decay or demineralised lesions (DLs, also known as white spot lesions) can appear on teeth during fixed orthodontic (brace) treatment. Fluoride reduces decay in susceptible individuals, including orthodontic patients. This review compared various forms of topical fluoride to prevent the development of DLs during orthodontic treatment. This is the second update of the Cochrane Review first published in 2004 and previously updated in 2013.\ud \ud Objectives\ud \ud The primary objective was to evaluate whether topical fluoride reduces the proportion of orthodontic patients with new DLs after fixed appliances.\ud \ud The secondary objectives were to examine the effectiveness of different modes of topical fluoride delivery in reducing the proportions of orthodontic patients with new DLs, as well as the severity of lesions, in terms of number, size and colour. Participant‐assessed outcomes, such as perception of DLs, and oral health‐related quality of life data were to be included, as would reports of adverse effects.\ud \ud Search methods\ud \ud Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 1 February 2019), the Cochrane Central Register of Controlled Trials (CENTRAL; 2019, Issue 1) in the Cochrane Library (searched 1 February 2019), MEDLINE Ovid (1946 to 1 February 2019), and Embase Ovid (1980 to 1 February 2019). The US National Institutes of Health Ongoing Trials Register (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases.\ud \ud Selection criteria\ud \ud Parallel‐group, randomised controlled trials comparing the use of a fluoride‐containing product versus a placebo, no treatment or a different type of fluoride treatment, in which the outcome of enamel demineralisation was assessed at the start and at the end of orthodontic treatment.\ud \ud Data collection and analysis\ud \ud At least two review authors independently, in duplicate, conducted risk of bias assessments and extracted data. Authors of trials were contacted to obtain missing data or to ask for clarification of aspects of trial methodology. Cochrane's statistical guidelines were followed.\ud \ud Main results\ud \ud This update includes 10 studies and contains data from nine studies, comparing eight interventions, involving 1798 randomised participants (1580 analysed). One report contained insufficient information and the authors have been contacted.\ud \ud We assessed two studies as at low risk of bias, six at unclear risk of bias, and two at high risk of bias.\ud \ud Two placebo (non‐fluoride) controlled studies, at low risk of bias, investigated the professional application of varnish (7700 or 10,000 parts per million (ppm) fluoride (F)), every six weeks and found insufficient evidence of a difference regarding its effectiveness in preventing new DLs (risk ratio (RR) 0.52, 95% confidence interval (CI) 0.14 to 1.93; 405 participants; low‐certainty evidence). One placebo (non‐fluoride) controlled study, at unclear risk of bias, provides a low level of certainty that fluoride foam (12,300 ppm F), professionally applied every two months, may reduce the incidence of new DLs (12% versus 49%) after fixed orthodontic treatment (RR 0.26, 95% CI 0.11 to 0.57; 95 participants).\ud \ud One study, at unclear risk of bias, also provides a low level of certainty that use of a high‐concentration fluoride toothpaste (5000 ppm F) by patients may reduce the incidence of new DLs (18% versus 27%) compared with a conventional fluoride toothpaste (1450 ppm F) (RR 0.68, 95% CI 0.46 to 1.00; 380 participants).\ud \ud There was no evidence for a difference in the proportions of orthodontic patients with new DLs on the teeth after treatment with fixed orthodontic appliances for the following comparisons:\ud \ud ‐ an amine fluoride and stannous fluoride toothpaste/mouthrinse combination versus a sodium fluoride toothpaste/mouthrinse,\ud \ud ‐ an amine fluoride gel versus a non‐fluoride placebo applied by participants at home once a week and by professional application every three months,\ud \ud ‐ resin‐modified glass ionomer cement versus light‐cured composite resin for bonding orthodontic brackets,\ud \ud ‐ a 250 ppm F mouthrinse versus 0 ppm F placebo mouthrinse,\ud \ud ‐ the use of an intraoral fluoride‐releasing glass bead device attached to the brace versus a daily fluoride mouthrinse.\ud \ud The last two comparisons involved studies that were assessed at high risk of bias, because a substantial number of participants were lost to follow‐up.\ud \ud \ud \ud Unfortunately, although the internal validity and hence the quality of the studies has improved since the first version of the review, they have compared different interventions; therefore, the findings are only considered to provide low level of certainty, because none has been replicated by follow‐up studies, in different settings, to confirm external validity.\ud \ud A patient‐reported outcome, such as concern about the aesthetics of any DLs, was still not included as an outcome in any study. Reports of adverse effects from topical fluoride applications were rare and unlikely to be significant. One study involving fluoride‐containing glass beads reported numerous breakages.\ud \ud Authors' conclusions\ud \ud This review found a low level of certainty that 12,300 ppm F foam applied by a professional every 6 to 8 weeks throughout fixed orthodontic treatment, might be effective in reducing the proportion of orthodontic patients with new DLs. In addition, there is a low level of certainty that the patient use of a high fluoride toothpaste (5000 ppm F) throughout orthodontic treatment, might be more effective than a conventional fluoride toothpaste. These two comparisons were based on single studies. There was insufficient evidence of a difference regarding the professional application of fluoride varnish (7700 or 10,000 ppm F). Further adequately powered, randomised controlled trials are required to increase the certainty of these findings and to determine the best means of preventing DLs in patients undergoing fixed orthodontic treatment. The most accurate means of assessing adherence with the use of fluoride products by patients and any possible adverse effects also need to be considered. Future studies should follow up participants beyond the end of orthodontic treatment to determine the effect of DLs on patient satisfaction with treatment.

This study evaluated the quality, reliability and readability of information on the Internet on adult orthodontics.A quality assessment of adult orthodontic websites.Postgraduate Orthodontic Unit, Cork University Dental School and Hospital, Cork, Ireland.An Internet search using three search engines (Google, Yahoo and Bing) was conducted using the terms ('adult orthodontics' and 'adult braces'). The first 50 websites from each engine and under each search term were screened and exclusion criteria applied. Included websites were then assessed for quality using four methods: the HON seal, JAMA benchmarks, the DISCERN instrument and the LIDA tool. Readability of included websites was assessed using the Flesch Reading Ease Score (FRES).Only 13 websites met the inclusion criteria. Most were of US origin (n = 8; 61%). The authors of the websites were dentists (n = 5; 39%), professional organizations (n = 2; 15%), past patients (n = 2; 15%) and unspecified (n = 4; 31%). Only 1 website displayed the HON seal and three websites contained all JAMA benchmarks. The mean overall score for DISCERN was 3.9/5 and the mean total LIDA score was 115/144. The average FRES score was 63.1/100.The number of informative websites on adult orthodontics is low and these are of moderate quality. More accurate, high-quality Internet resources are required on adult orthodontics. Recommendations are made as to how this may be achieved.

Background: Initial arch wires are the first arch wires to be inserted into the fixed appliance at the beginning of orthodontic treatment and are used mainly for the alignment of teeth by correcting crowding and rotations. With a number of different types of orthodontic arch wires available for initial tooth alignment, it is important to understand which wire is most efficient, as well as which wires cause least amount of root resorption and pain during the initial aligning stage of treatment. This is an update of the review entitledInitial arch wires for alignment of crooked teeth with fixed orthodontic braces, which was first published in 2010. Objectives: To assess the effects of initial arch wires for the alignment of teeth with fixed orthodontic braces, in terms of the rate of tooth alignment, amount of root resorption accompanying tooth movement, and intensity of pain experienced by patients during the initial alignment stage of treatment. Search methods: Cochrane Oral Health's Information Specialist searched the following databases: Cochrane Oral Health's Trials Register (to 5 October 2017), the Cochrane Central Register of Controlled Trials (CENTRAL) (the Cochrane Library, 2017, Issue 9), MEDLINE Ovid (1946 to 5 October 2017), and Embase Ovid (1980 to 5 October 2017. The US National Institutes of Health Trials Registry (ClinicalTrials.gov) and the World Health Organization International Clinical Trials Registry Platform were searched for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. Selection criteria: We included randomised controlled trials (RCTs) of initial arch wires to align teeth with fixed orthodontic braces. We included only studies involving participants with upper or lower, or both, full arch fixed orthodontic appliances. Data collection and analysis: Two review authors were responsible for study selection, 'Risk of bias' assessment and data extraction. We resolved disagreements by discussion between the review authors. We contacted corresponding authors of included studies to obtain missing information. We assessed the quality of the evidence for each comparison and outcome as high, moderate, low or very low, according to GRADE criteria. Main results: For this update, we found three new RCTs (228 participants), bringing the total to 12 RCTs with 799 participants. We judged three studies to be at high risk of bias, and three to be at low risk of bias; six were unclear. None of the studies reported the adverse outcome of root resorption. The review assessed six comparisons. 1. Multistrand stainless steel versus superelastic nickel-titanium (NiTi) arch wires. There were five studies in this group and it was appropriate to undertake a meta-analysis of two of them. There is insufficient evidence from these studies to determine whether there is a difference in rate of alignment between multistrand stainless steel and superelastic NiTi arch wires (mean difference (MD) -7.5 mm per month, 95% confidence interval (CI) -26.27 to 11.27; 1 study, 48 participants; low-quality evidence). The findings for pain at day 1 as measured on a 100 mm visual analogue scale suggested that there was no meaningful difference between the interventions (MD -2.68 mm, 95% CI -6.75 to 1.38; 2 studies, 127 participants; moderate-quality evidence). 2. Multistrand stainless steel versus thermoelastic NiTi arch wires. There were two studies in this group, but it was not appropriate to undertake a meta-analysis of the data. There is insufficient evidence from the studies to determine whether there is a difference in rate of alignment between multistrand stainless steel and thermoelastic NiTi arch wires (low-quality evidence). Pain was not measured. 3. Conventional NiTi versus superelastic NiTi arch wires. There were three studies in this group, but it was not appropriate to undertake a meta-analysis of the data. There is insufficient evidence from these studies to determine whether there is any difference between conventional and superelastic NiTi arch wires with regard to either alignment or pain (low- to very low-quality evidence). 4. Conventional NiTi versus thermoelastic NiTi arch wires. There were two studies in this group, but it was not appropriate to undertake a meta-analysis of the data. There is insufficient evidence from these studies to determine whether there is a difference in alignment between conventional and thermoelastic NiTi arch wires (low-quality evidence). Pain was not measured. 5. Single-strand superelastic NiTi versus coaxial superelastic NiTi arch wires. There was only one study (24 participants) in this group. There is moderate-quality evidence that coaxial superelastic NiTi can produce greater tooth movement over 12 weeks (MD -6.76 mm, 95% CI -7.98 to -5.55). Pain was not measured. 6. Superelastic NiTi versus thermoelastic NiTi arch wires. There were three studies in this group, but it was not appropriate to undertake a meta-analysis of the data. There is insufficient evidence from these studies to determine whether there is a difference in alignment or pain between superelastic and thermoelastic NiTi arch wires (low-quality evidence). Authors' conclusions: Moderate-quality evidence shows that arch wires of coaxial superelastic nickel-titanium (NiTi) can produce greater tooth movement over 12 weeks than arch wires made of single-strand superelastic NiTi. Moderate-quality evidence also suggests there may be no difference in pain at day 1 between multistrand stainless steel arch wires and superelastic NiTi arch wires. Other than these findings, there is insufficient evidence to determine whether any particular arch wire material is superior to any other in terms of alignment rate, time to alignment, pain and root resorption.

Introduction In this study, we aimed to compare the incidence of new demineralized lesions and bond failures between 2 groups of participants wearing fixed orthodontic appliances bonded with either light-cured resin-modified glass ionomer cement or light-cured composite. Methods This trial was a multicenter (6 centers: 2 teaching hospitals, 4 specialist orthodontic practices), single-blinded, randomized controlled trial with 2 parallel groups. Patients aged 11 years or older, in the permanent dentition, and about to start fixed orthodontic treatment in these 6 centers were randomly allocated to have either resin-modified glass ionomer cement or light-cured composite for bonding brackets, forward of the first molars. Pretreatment and day-of-debond digital photographic images were taken of the teeth and assessed by up to 5 clinical and 3 lay assessors for the presence or absence of new demineralized lesions and the esthetic impact. The assessors were masked as to group allocation. Results We randomized 210 participants, and 197 completed the trial. There were 173 with complete before-and after-digital images of the teeth. The incidence of new demineralized lesions was 24%; but when the esthetic impact was taken into account, this was considerably lower (9%). There was no statistically significant difference between the bracket adhesives in the numbers with at least 1 new demineralized lesion (risk ratio,1.25; 95% confidence interval, 0.74-2.13; P = 0.403) or first-time bracket failure (risk ratio,0.88; 95% confidence interval, 0.67-1.16; P = 0.35). There were no adverse effects. Conclusions There is no evidence that the use of resin modified glass ionomer cement over light-cured composite for bonding brackets reduces the incidence of new demineralized lesions or bond failures. There might be other reasons for using resin modified glass ionomer cement. Registration This trial was registered at ClinicalTrials.gov NCT01925924 . Protocol The protocol is available from the corresponding author on request.

Background/objectives Functional appliances are commonly used to correct Class II malocclusion. This study aimed to compare the facial soft tissue changes in Caucasians between pre-treatment and with the construction bite versus pre-treatment and completion of treatment with a modified Twin-block appliance (MTBA). Materials and methods Fifty-eight Caucasian subjects with Class II division 1 malocclusion had 3D stereophotogrammetric images captured pre-treatment (T1), with the construction bite (T2), and on completion of MTBA treatment (T3). Twenty-six landmarks were located on each image and 10% were re-landmarked 1 month later. Soft-tissue linear and volumetric changes (T1-T2 and T1-T3) were analyzed using linear mixed effect models (SAS® Version 9.4, www.sas.com). Results Forty-seven subjects [mean age 13.2 (SD 1.7) years] completed treatment [mean duration 9.8 (SD 3.8) months]. Differences between the changes from T1 to T2 versus T1 to T3 for upper facial and upper lip landmarks were insignificant (all P > 0.05) except for nasion, orbitale right, pronasale, and subnasale. For the same comparisons, lower lip and chin landmarks changed significantly (all P < 0.05) as did facial soft tissue volume (P< 0.0001). Limitations There was no control group. Conclusion The facial soft tissue changes from pre-treatment to with the construction bite were considerably more than those from pre-treatment to completion of treatment with a MTBA. Implication With MTBA treatment, the soft tissue changes from pre-treatment to with the construction bite in situ, overestimate those from pre- to post-treatment.

The need for long-term retention following orthodontic treatment is now considered essential to prevent post-orthodontic treatment relapse. The vacuum-formed retainer (VFR) has gained popularity in recent times. This paper describes briefly the characteristics of VFRs and summarizes the evidence in relation to their effectiveness. Clinical Relevance: VFRs are now widely used after orthodontic treatment and it is important that clinicians adopt an evidenced-based approach to their use.

BACKGROUND: Correction of the type of dental problem where the bite is deep and the upper front teeth are retroclined (Class II division 2 malocclusion) may be carried out using different types of orthodontic treatment. However, in severe cases, surgery to the jaws in combination with orthodontics may be required. In growing children, treatment may sometimes be carried out using special upper and lower dental braces (functional appliances) that can be removed from the mouth. In many cases this treatment does not involve taking out any permanent teeth. Often, however, further treatment is needed with fixed braces to get the best result. In other cases, treatment aims to move the upper first permanent molars backwards to provide space for the correction of the front teeth. This may be carried out by applying a force to the teeth and jaws from the back of the head using a head brace (headgear) and transmitting this force to a part of a fixed or removable dental brace. This treatment may or may not involve the removal of permanent teeth. In some cases, neither functional appliances nor headgear are required and treatment may be carried out without extraction of any permanent teeth. Instead of using a headgear, in certain cases, the back teeth are held back in other ways such as with an arch across or in contact with the front of the roof of the mouth which links two bands glued to the back teeth. Often in these cases, two permanent teeth are taken out from the middle of the upper arch (one on each side) to provide room to correct the upper front teeth. It is important for orthodontists to find out whether orthodontic treatment only, carried out without the removal of permanent teeth, in children with a Class II division 2 malocclusion produces a result which is any different from no orthodontic treatment or orthodontic treatment only involving extraction of permanent teeth. OBJECTIVES: To establish whether orthodontic treatment, carried out without the removal of permanent teeth, in children with a Class II division 2 malocclusion, produces a result which is any different from no orthodontic treatment or orthodontic treatment involving removal of permanent teeth. SEARCH STRATEGY: The Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE were searched. The handsearching of the main international orthodontic journals was updated to April 2006. There were no restrictions with regard to publication status or language of publication. International researchers, likely to be involved in Class II division 2 clinical trials, were contacted to identify any unpublished or ongoing trials. SELECTION CRITERIA: Trials were selected if they met the following criteria: randomised controlled trials (RCTs) and controlled clinical trials (CCTs) of orthodontic treatments to correct deep bite and retroclined upper front teeth in children. DATA COLLECTION AND ANALYSIS: Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were to be conducted in duplicate and independently by two review authors. Results were to be expressed as random-effects models using mean differences for continuous outcomes and risk ratios for dichotomous outcomes with 95% confidence intervals. Heterogeneity was to be investigated including both clinical and methodological factors. MAIN RESULTS: No RCTs or CCTs were identified that assessed the treatment of Class II division 2 malocclusion in children. AUTHORS' CONCLUSIONS: It is not possible to provide any evidence-based guidance to recommend or discourage any type of orthodontic treatment to correct Class II division 2 malocclusion in children.

To compare mean anterior (AR) and mean overall (OR) tooth size ratios, prevalence of clinically significant tooth size discrepancies (TSDs) and correlation between AR and OR in subjects with Class II division 1 and Class III malocclusion treated by surgical-orthodontic or orthodontic means.Retrospective, cross-sectional.State-funded and private clinics.From pre-treatment cohorts of 770 surgical and 610 non-surgical subjects, Class II division 1 and Class III malocclusion groups were identified with 60 surgical and 60 non-surgical subjects, comprising 30 males and 30 females, in each.AR and OR were calculated by landmarking digital models. Differences in AR and OR and their relationship were analysed using two-way analysis of variance (ANOVA) and a correlation coefficient, respectively. The proportions of the surgical and non-surgical groups with a TSD were assessed using logistic regression. Intra-examiner reproducibility involved re-landmarking 30 randomly selected image sets and differences in ARs and ORs were compared using a paired t-test. Random error was assessed using the intraclass correlation coefficient (ICC). Analyses were performed using SAS (SAS Institute Inc., Cary, NC, USA) at the 5% level of significance.There were no statistically significant differences associated with the measurement of either the mean AR (P = 0·913) or the mean OR (P = 0·874). ICC values were very high (AR = 0·95; OR = 0·90). Differences existed between both Class II and Class III surgical (AR: P0·001; OR: P0·001) and non-surgical groups (AR: P = 0·012; OR: P = 0·003). The AR and OR relationship was strong (correlation coefficient = 0·72). The highest percentage of clinically significant TSDs was seen in the AR of both Class II and Class III surgical groups (23·3%).In the cohort examined: AR and OR differed significantly for malocclusion groups. The prevalence of clinically significant TSDs did not differ significantly between surgical and non-surgical groups although the highest percentage of clinically significant TSDs was recorded for AR in Class II and Class III surgical cases. AR and OR were closely related.

Mild resting facial asymmetry exists in clinically symmetrical faces, but the effect of smiling on the magnitude of overall facial asymmetry in adults has not been assessed. The aim of the present study was to use stereophotogrammetry to quantify the effect of smiling on overall facial asymmetry in Caucasian adults who presented with Class I incisor relationships and no history of orthodontic treatment.Twenty male and 20 female Caucasians aged 1 8-30 years with no history of orthodontic treatment, a clinically symmetrical face and a Class I incisor relationship had 3D stereophotogrammetric images captured at rest and on natural and maximal smile (T1). The images were repeated 2-4 weeks later (T2) to assess expression reproducibility. Overall facial asymmetry scores were produced from 27 landmarks using partial Ordinary Procrustes Analysis (OPA) and assessed by an Analysis of Covariance (ANCOVA) model. A random sample of the images was re-examined two months later to calculate intraobserver landmark reproducibility.Mean landmark error was low (0.41 ± 0.07 mm). Mean overall facial asymmetry scores were not significantly gender different (p = 0.5300); therefore, the male and female data were pooled. Mean overall facial asymmetry scores for maximal (0.91 ± 0.16) and natural smile (0.88 ± 0.18) were higher than at rest (0.80 ± 0.17) (p0.0001) and were reproducible across (T1-T2) sessions (p = 0.3204).Overall 3D facial asymmetry scores for the sampled Caucasian adults with clinically symmetrical faces increased in magnitude from rest to natural and to maximal smile. Clinicians should assess overall facial asymmetry at rest and on natural and maximal smile at baseline, during treatment and as part of a core outcome assessment, particularly for cases with unilateral posterior crossbite, unilateral cleft lip and palate or skeletal asymmetry.

To investigate the use of bonded molar tubes (BMTs) by specialist orthodontists.Prospective postal questionnaire.Ireland.Registered members of the Orthodontic Society of Ireland.A questionnaire was posted to registered members of the Orthodontic Society of Ireland. It investigated demographics, pattern of use, reasons for use and techniques for placement of BMTs.A 74% response rate was obtained. In more than 80% of cases, BMTs were used on first and second permanent molars by 52% and 33% of orthodontists respectively. BMT usage was adopted by 97% of respondents in the previous decade. Direct bonding was used by all for BMT placement. Etch times for molars, compared to other teeth, increased from 15 to 30 seconds by 51% of orthodontists. Of the respondents, 97% used light-cured adhesives and 17% used self-etching primers. Molar tube holders were preferred by 54% for placement. Only with a history of epilepsy, were bands preferred to BMTs. BMTs were regarded as more cost-effective than molar bands by 66% of responding clinicians.Specialist orthodontists preferred BMTs to bands on first permenent molars. Direct bonding was favoured using a 30-second etch, a light-cured primer and adhesive with specialized molar tube holders. BMTs were perceived to be more cost-effective than molar bands.

The objective of this study was to determine if increased overjet (greater than 6 mm) influences the magnitude and reproducibility of natural smile and maximal smile in Caucasian adult females. Twenty adult females with an increased overjet (6–10 mm) and 20 control adult females (overjet 2–4 mm) with no history of orthodontic treatment volunteered to participate. The mean age in the control group was 30.1 ± 6.4 years and the mean age in the test group was 31.9 ± 10.8 years. Three-dimensional stereophotogrammetric images were captured of each subject for three expressions: at rest, natural smile, and maximal smile. The images were recorded twice on two separate occasions, 6 weeks apart. Images were landmarked and a partial ordinary Procrustes superimposition was used to adjust for the differences in head posture between the same expressions. The magnitude of movement relative to the rest position, averaged over all the landmarks, was calculated and compared between the groups using analysis of variance (linear mixed-effects model); the intra- and inter-session reproducibility of both expressions was assessed. There was greater mean movement, averaged over all the landmarks, in the control group than in the increased overjet group for both natural smile and maximal smile ( P = 0.0068). For these expressions, there were no statistically significant differences in reproducibility within sessions ( P = 0.5403) or between sessions ( P = 0.3665). Increased overjet had a statistically significant effect on the magnitude of smiling but did not influence the reproducibility of natural or maximal smile relative to controls.

Objective: To determine the prevalence of tooth size discrepancies (TSDs) in an Irish orthodontic population among different malocclusion groups. Materials and Methods: From 850 pretreatment sets of orthodontic models at a university clinic, 240 were selected with 30 female and 30 male sets for each malocclusion (Class I, Class II division 1, Class II division 2, and Class III). Digital models were produced, and the mesial and distal contact points were digitized to calculate overall and anterior tooth size ratios. The differences between the male and female groups and among the malocclusion groups were analyzed using two-way analysis of variance (ANOVA) (P , .05). Results: A clinically significant anterior TSD (more than two standard deviations from the Bolton means) existed in 37.9% of the subjects. No differences existed in the prevalence of overall TSDs between the male and female groups (P 5 .5913) or among the malocclusion groups (P 5 .0809). For the mean anterior tooth size ratios in the male group, the values for Class III and Class II division 2 were higher than in Class II division 1, and the value for Class II division 2 was higher than in Class I (P 5 .0184). Conclusions: The prevalence of anterior tooth size discrepancies in this sample of Irish orthodontic patients was 37.9%. There were no statistically significant differences in the prevalence of mean overall TSDs with regard to malocclusion or gender. In the male group, the mean anterior tooth size ratio was higher in Class III and in Class II division 2 malocclusion than in Class II division 1 and higher in Class II division 2 malocclusion than in Class I malocclusion. (Angle Orthod. 2011;81:130–133.)

OBJECTIVE: To screen patients with oligoarticular and polyarticular forms of Juvenile Idiopathic Arthritis (JIA) to determine (i) the severity of their class II skeletal pattern; (ii) temporomandibular joint signs and symptoms and (iii) use of systemic corticosteroids. DESIGN: Cross-sectional screening. SUBJECTS AND SETTING: Sixty-eight children with JIA aged between 9 and 16 years old who were screened at four regional treatment centres in the UK. METHOD: Patients were screened clinically and radiographically for the presence of class II skeletal pattern and temporomandibular (TMJ) pain dysfunction syndrome. In addition, the JIA sub-type and history of disease activity and medication were recorded. MAIN OUTCOME MEASURES: Class II skeletal pattern, TMJ signs and symptoms, use of systemic corticosteroids. RESULTS: The mean ANB values were 4.2 degrees (SD = 2.9 degrees) in the oligoarticular group and 5.1 degrees (SD = 3.8 degrees) in the polyarticular group. Just under one-third of children had a moderate or severe class II skeletal pattern and a further quarter of children had a mild class II skeletal pattern. Clinical signs and symptoms of temporomandibular joint pain dysfunction syndrome were low (

Background: To determine the relationship between clinically significant tooth size discrepancies (TSD) and archform classification in orthodontic patients. Material and Methods: Two hundred and forty consecutive sets of pre-treatment orthodontic study models were scanned and landmarked. All models had permanent teeth erupted from first molar to first molar in both arches. Sixty sets of images were classified into two groups of 30 according to the presence (group 1) or absence (group 2) of a clinically significant overall or anterior TSD (>2 SD from Bolton’s original means). Mean upper and lower archforms were created for each group using a fourth degree polynomial curve. Upper and lower archforms in each group were classified as square, tapering or ovoid; their distribution was analysed using the Fisher test with a 5% level of significance. To evaluate the intra-operator error when determining archform type, the 60 archforms were re-classified by the same operator two weeks later. The unweighted Kappa statistic at 95% confidence intervals was used to determine the similarity of the classification on the two occasions. Results: Reproducibility of the classification of archform was very good (unweighted Kappa statistic of 0.83 with a 95% confidence interval of 0.73, 0.93). There was no statistically significant difference in the distribution of archform type between group 1 and group 2 for the upper ( p =0.3305) or lower ( p =0.6310) arches. Conclusions: The presence of a clinically significant TSD and archform classification do not appear to be related.

To evaluate the effectiveness of different retention strategies used to maintain tooth position after treatment by orthodontic appliances.The search strategy was carried out according to the standard Cochrane systematic review methodology. The following databases were searched for randomized clinical trials (RCT) or controlled clinical trials (CCT): Cochrane Oral Health Group Trials Register, Cochrane Clinical Trials Register, MEDLINE and EMBASE. No language restrictions were applied. Authors of trials were contacted to identify unpublished trials. Inclusion and exclusion criteria were applied when considering the studies to be included and a quality assessment made for each paper.The primary outcome was the amount of relapse. Secondary outcomes were survival of retainers, adverse effects on oral health and patient satisfaction.Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in duplicate and independently by two reviewers. Five studies (2 RCTs and 3 CCTs) fulfilled the inclusion criteria.There was evidence, based on data from one trial, that there was a statistically significant increase in stability in both the mandibular (P0.001) and maxillary anterior segments (P0.001) when the CSF (circumferential supracrestal fiberotomy) was used in conjunction with a Hawley retainer, compared with a Hawley retainer alone. However, this evidence may be unreliable due to flaws in the study design. There was also weak, unreliable evidence that teeth settle quicker with a Hawley retainer than with a clear overlay retainer after 3 months.There is currently insufficient evidence on which to base the clinical practice of orthodontic retention.

Objective To evaluate dental arch relationships and dimensions, relative to an age matched noncleft sample, in Caucasian 3-year-old children with repaired unilateral cleft lip (UCL) or unilateral cleft lip and palate (UCLP). Design Prospective, cross-sectional, case-control study performed in Scotland, U.K. Participants Eleven children with repaired unilateral cleft lip, 16 children with repaired unilateral cleft lip and palate, and 78 children as controls. Main Outcome Measures Dental arch relationships and linear arch dimensions. Results Prevalence of Class III incisor relationship was 31.3% in children with unilateral cleft lip and palate compared with 9.1% in children with unilateral cleft lip. A buccal crossbite was present in 36% of children with unilateral cleft lip, compared with 75.6% of children with unilateral cleft lip and palate. Mean linear maxillary arch dimensions did not differ significantly between children with unilateral cleft lip and the controls. Except for second intermolar width, statistically significant differences existed in mean linear maxillary arch dimensions between the unilateral cleft lip and the unilateral cleft lip and palate groups; the mean linear maxillary arch dimensions were significantly greater in the control group than in the unilateral cleft lip and palate group. The mean cleft-affected anterior quadrant length appeared to be the arch dimension with the greatest power of discrimination among the three groups. There were no significant differences in mean linear mandibular arch dimensions among the three groups. Conclusions Anterior crossbite was almost three times more common in the unilateral cleft lip and palate group than in the unilateral cleft lip group. Mean linear maxillary arch dimensions differed significantly between the unilateral cleft lip and palate group and the control group. There were no significant differences in mean linear maxillary arch dimensions between unilateral cleft lip and controls or between mean linear mandibular arch dimensions for unilateral cleft lip, unilateral cleft lip and palate, and controls.

To evaluate the effectiveness of fluoride in preventing white spot lesion (WSL) demineralization during orthodontic treatment and compare all modes of fluoride delivery.The search strategy for the review was carried out according to the standard Cochrane systematic review methodology. The following databases were searched for RCTs or CCTs: Cochrane Clinical Trials Register, Cochrane Oral Health Group Specialized Trials Register, MEDLINE and EMBASE. Inclusion and exclusion criteria were applied when considering studies to be included. Authors of trials were contacted for further data.The primary outcome of the review was the presence or absence of WSL by patient at the end of treatment. Secondary outcomes included any quantitative assessment of enamel mineral loss or lesion depth.Six reviewers independently, in duplicate, extracted data, including an assessment of the methodological quality of each trial.Fifteen trials provided data for this review, although none fulfilled all the methodological quality assessment criteria. One study found that a daily NaF mouthrinse reduced the severity of demineralization surrounding an orthodontic appliance (lesion depth difference -70.0 microm; 95% CI -118.2 to -21.8 microm). One study found that use of a glass ionomer cement (GIC) for bracket bonding reduced the prevalence of WSL (Peto OR 0.35; 95% CI 0.15-0.84) compared with a composite resin. None of the studies fulfilled all of the methodological quality assessment criteria.There is some evidence that the use of a daily NaF mouthrinse or a GIC for bonding brackets might reduce the occurrence and severity of WSL during orthodontic treatment. More high quality, clinical research is required into the different modes of delivering fluoride to the orthodontic patient.

The aims of this study were to determine the mean tensile force of four different elastomeric modules, the archwire seating force of different ligation methods, and its effect on frictional resistance. To determine the mean tensile force, each elastomeric module (purple, grey, Alastik, and SuperSlick) was extended by 5 mm using two hooks attached to a load cell using a Nene M3000 testing machine. To assess the median archwire seating force, a maxillary premolar bracket (3M Unitek) was welded to a sheet of stainless steel (SS) and glued to a Perspex block. The bracket base was removed and the cut continued into the Perspex below. A length of test wire was taken and bent to form a "U" shape, with the middle portion 20 mm in length. The free ends of the wire were secured to the load cell of the Nene testing machine. Two wire sizes were tested, 0.017 x 0.025 and 0.019 x 0.025 inch SS. The load cell was activated and the force with which the wire was displaced into the slot by the ligation method was measured. Four types of elastomeric module were tested together with a pre-formed 0.09 inch SS ligature. The experimental method used to determine the mean frictional force of each module and wire size was carried out using a method described previously. Statistically significant differences existed in the mean tensile forces and median archwire seating forces between the elastomeric modules. Grey modules with either size wire produced the lowest median archwire seating force, whereas SS ligatures produced the highest forces. SS ligatures with either wire produced the lowest mean frictional forces, whereas grey modules produced significantly higher mean frictional force (P < 0.01). The force with which the wire was seated into the bracket did not seem to be related to the subsequent amount of mean frictional force produced.

Objective To validate a new method of facial volumetric assessment that is dependent on the use of stereophotogrammetric models and a software-based Facial Analysis Tool. Design The method was validated in vitro with three-dimensional (3D) models of a lifelike plastic female dummy head and in vivo with a male-subject head. Methods Thirty facial silicone explants were added in the nasal and perioral regions of each head, and their volumes were obtained by three different algorithms. These were compared with the actual values obtained by a “water displacement” method. Results The least mean error was found with the “tetrahedron formation” method followed by the “projection” method and the “back-plane construction” method. The error with the tetrahedron formation method was 0.071 cm3 (95% confidence interval [CI]: −0.074 to 0.2161 cm3) with the in vitro models and 0.314 cm3 (95% CI: −0.080 to 0.708 cm3) with the in vivo models. The increased volumetric assessment error observed in vivo was attributed to the registration procedure and possible changes in facial expression. Conclusions These results encourage the use of this method in the 3D assessment of orthognathic surgical outcome, provided a standardized facial expression is used for image acquisition.

Objective To review the stimulus media, measurements and scoring system, rater's characteristics, and facial region used in assessment of the appearance of cleft-related deformity. Methods A review of the literature was conducted using MedLine from January 1966 to June 2003. Key orthodontic journals and The Cleft Palate–Craniofacial Journal were hand searched as well. Results Most studies used a static two-dimensional means of assessment. Direct clinical assessment, three-dimensional media, or both have been used to a lesser extent. Only one study utilized all three assessment media. Three studies, however, attempted to compare the direct clinical assessment with that obtained using two-dimensional media. Most of the studies demonstrated that appearance of the cleft-related deformity could be measured by a variety of judges. The reliability and validity of the three different media as methods of assessment have received limited attention. The facial area assessed has varied from the full face, nasolabial area, or specific features of the lip or nose. Conclusions Wide variation exists in the study design related to assessment of cleft-related deformity. An internationally agreed objective method of assessment for this facial deformity is required. A three-dimensional, rather than a two-dimensional, means of assessment should be adopted.

We developed a new three-dimensional (3D) method of analysis of facial asymmetry and applied it to 44 patients: 20 Class III cases treated by bimaxillary osteotomy; 12 Class III cases treated by maxillary advancement alone, and 12 Class II cases treated by bimaxillary operations. 3D images were taken within a week before operation (T1), and one (T2), three (T3), and six (T4) months after operation. Landmarks were digitised on each 3D model and facial asymmetry scores were calculated. In the bimaxillary osteotomy group, facial symmetry improved after operation. In the maxillary advancement group, there was no notable improvement in facial symmetry after operation. In the bimaxillary group, facial symmetry deteriorated after operation, particularly at the tip of the nose and prominence of the chin. At six months follow-up, the changes in facial asymmetry in the three groups were not significant.

The aim of the study was to investigate the effect of elastomeric type and stainless steel (SS) ligation on frictional resistance using a validated method. To assess the validity of the new test system to measure mean frictional forces, SS and TMA wires, each with dimensions of 0.017 x 0.025 and 0.019 x 0.025 inches, were used in combination with a self-ligating Damon II bracket or a conventional preadjusted edgewise premolar SS bracket without ligation. Four types of elastomeric module, purple, grey, Alastik or SuperSlick, and a pre-formed 0.09 inch SS ligature were then assessed as methods of ligation using preadjusted edgewise premolar SS brackets. The specimens were tested on a Nene M3000 testing machine, with a crosshead speed of 5 mm/minute and each test run lasted for 4 minutes. Each bracket/wire combination with each method of ligation was tested 10 times in the presence of human saliva and the mean frictional force was recorded. The mean frictional forces were compared using three-way analysis of variance. The Damon II self-ligating bracket and unligated conventional SS bracket produced negligible mean frictional forces with any of the wires tested. For the 0.017 x 0.025 SS, 0.019 x 0.025 SS or 0.019 x 0.025 inch TMA wires, SS ligatures produced the lowest mean frictional forces. With the 0.017 x 0.025 TMA wire, purple modules produced the lowest mean frictional force. There was no consistent pattern in the mean frictional forces across the various combinations of wire type, size and ligation method. Under the conditions of this experiment, the use of passive self-ligating brackets is the only method of almost eliminating friction.

Part I of this paper describes the background, general concepts, available techniques and the clinical applications of recording external craniofacial morphology in three dimensions. Part II explores the different 3D techniques of imaging the dental arches, and their possible uses in orthodontic diagnosis and treatment.

The aims of this in vitro study were to compare the cariostatic potential of a resin modified glass ionomer cement (Fuji Ortho LC) to that of a resin control (Transbond) for bracket bonding and to compare the effect of extrinsic fluoride application on the cariostatic potential of each material.Ex vivo study.Orthodontic brackets were bonded to 40 extracted premolars, 20 with Fuji Ortho LC and 20 with Transbond. The teeth were subjected to pH cycling, pH 4.55, and pH 6.8, over a 30-day period. Ten teeth bonded with each material were immersed in a 1000 ppm fluoride solution for 2 minutes each day. Fluoride release was measured throughout the study from all teeth. After 30 days, the teeth were assessed visually for signs of enamel decalcification.Significant differences in decalcification existed macroscopically between all four groups of teeth, with the exception of those bonded with Fuji Ortho LC alone compared with Transbond alone (P = 0.22), and Fuji Ortho LC alone compared with Transbond with added fluoride (P = 0.3). Fluoride release from Fuji Ortho LC alone fell to minimal values, but with the addition of extrinsic fluoride the levels fell initially and then followed an upward trend. There was minimal fluoride release, from Transbond alone, but with daily addition of extrinsic fluoride, subsequent fluoride release was increased. Significant differences existed in the amount of fluoride released between all groups, except comparing Fuji Ortho LC alone and Transbond with added fluoride.The results of this study have indicated that with an in vitro tooth-bracket model, the creation of white spot inhibition could best be achieved by the use of a resin-modified glass ionomer cement, supplemented with fluoride exposure. The least protection was afforded by the composite control. The resin-modified glass ionomer cement alone and the composite with added fluoride demonstrated equivalent protection.

The aim of the present study was to compare the mean bonding time, mean shear bond strength and mean survival time of stainless steel brackets with a micro-etched base bonded with a light-cure composite using a self-etching primer (SEP) or a conventional two-stage etch and prime system. Brackets were bonded to 30 premolars with each bonding system. The bonding time was recorded for each specimen using a stopwatch. After storage in a humidor at 37°C for 24 hours, the shear debonding force was measured at a crosshead speed of 0.5 mm/minute. Another 10 premolars were bonded with each bonding system and used to assess survival time following the application of mechanical stress in a ball mill for 100 hours. The mean bonding time of the SEP group (111.5 seconds) was significantly less than that of the two-stage bonding group (170.5 seconds) [mean difference 59 seconds; 95 per cent confidence interval (CI) 51.8–66.2 seconds, two sample t-test P < 0.001]. The mean shear bond strength of the SEP group (2.88 MPa) was significantly less than that of the two-stage bonding group (3.71 MPa) (mean difference 0.83 MPa; 95 per cent CI 0.23–1.42 MPa; two sample t-test P = 0.008). For the survival study, only one of the two-stage bonding group failed within 1 hour in the ball mill. The SEP significantly reduced bracket bonding time. The mean shear bond strength of the brackets bonded with the SEP was significantly less than those bonded with a conventional two-stage etch and prime system. There was no difference in survival time of brackets bonded by each bonding system.

Objectives: To determine the extent of reproducibility of five facial expressions. Design: Thirty healthy Caucasian volunteers (15 males, 15 females) aged 21 to 30 years had 20 landmarks highlighted on the face with a fine eyeliner pencil. Subjects were asked to perform a sequence of five facial expressions that were captured by a three-dimensional camera system. Each expression was repeated after 15 minutes to investigate intrasession expression reproducibility. To investigate intersession expression reproducibility, each subject returned 2 weeks after the first session. A single operator identified 3-dimensional coordinate values of each landmark. A partial ordinary procrustes analysis was used to adjust for differences in head posture between similar expressions. Statistical analysis was undertaken using analysis of variance (linear mixed effects model). Results: Intrasession expression reproducibility was least between cheek puffs (1.12 mm) and greatest between rest positions (0.74 mm). The r...

The past decade, has seen a wholesale shift in medical UK training towards outcome-based learning with the consequent development of an assessment method concentrating on what doctors do in everyda...

At an orthodontic meeting in recent years, a colleague recounted to me that when a presenter had finished their presentation on a systematic review, the person beside leaned over and said to my col...

Reason for withdrawal from publication Protocol has been withdrawn as it is a non-priority topic. To view the published versions of this article, please click the 'Other versions' tab.

BACKGROUND/OBJECTIVES: Social perceptions are influenced by dental appearance. The aim of this study was to determine whether social perceptions of a young adult are influenced by orthodontic retainer design and appearance. MATERIALS AND METHODS: Following ethical approval, a pilot-tested questionnaire study was conducted with 402 third-level students from the Republic of Ireland. Each participant was invited to look at one randomly allocated colour full-face smiling photograph of a young adult male or a young adult female wearing one of five maxillary retainers and asked to make judgements on a Likert scale concerning the subject’s social competence (SC), psychological adjustment (PA), intellectual ability (IA), and attractiveness. Five computer-modified standardized photographs of each subject wearing each of the following retainers were used: Essix, conventional Hawley, acrylated Hawley, and Begg; an image with no retainer simulated a bonded retainer (BR) appearance. Statistical analyses were performed in SAS® (Version 9.2). RESULTS: No significant differences were found between the retainers for SC ( P = 0.6741) and PA ( P = 0.7217). In the male subject only, greater perceived IA was found with the BR appearance compared to that of the conventional Hawley ( P = 0.0018) or the acrylated Hawley ( P = 0.0016). The BR appearance was perceived as more attractive than that of the Begg retainer ( P = 0.0103). LIMITATIONS: In this study, participants were required to make arbitrary judgements on a single image, which may not be a complete representation of a person. CONCLUSIONS/IMPLICATIONS: Social perceptions were found to be influenced by retainer design and appearance. This may be a factor in determining retainer choice.

To evaluate retention protocols and use of vacuum-formed retainers (VFRs) among specialist orthodontists.Postal/electronic (e-) questionnaire.Republic of Ireland.Members of the Dental Council of Ireland Specialist Register of Orthodontists and/or Orthodontic Society of Ireland.A pilot-tested questionnaire was distributed to 123 eligible specialist orthodontists. Questions addressed respondent demographics, preferred retainer choice in the maxillary and mandibular arches, prescribed wear protocols, VFR characteristics and factors influencing retainer choice. Statistical analyses were performed using PASW® version 18.The response rate was 82%. VFRs were the most commonly chosen retainer, prescribed by 53% of respondents in the maxilla and 33% in the mandible. Full-time followed by part-time wear of removable retainers (RRs) was the wear protocol favoured by the majority (70-76%). Full occlusal coverage was the VFR design favoured by 93%. VFR sheet thicknesses of 1.0 mm (68%) and 0.75 mm (16%) were most commonly prescribed. Seventeen per cent were aware that their patients used their VFRs as a receptacle for dental bleaching gel. Life-time wear of retainers was advised by 67-78%. The operator factor that most influenced retainer choice was the pre-treatment situation (88%).VFRs were the most common retainer choice in the maxilla and mandible with full-time wear followed by part-time wear of RRs favoured by most. Full occlusal coverage with a thickness of 1.0 mm was the VFR design prescribed by the majority. More than one in six specialist orthodontists were aware that their patients used their VFRs as a receptacle for dental bleaching gel.

This retrospective study was designed to assess skeletal stability after the correction of mandibular prognathism by sagittal split osteotomy (SSO) and intraoral vertical subsigmoid osteotomy (VSO). We used lateral cephalographs of 31 patients taken before, immediately after, and at least one year after the operation. We recorded euclidean distance matrix analysis, linear and angular measurements, and x and y co-ordinates of cephalometric landmarks for each cephalograph. There were no significant differences in extent of the mandibular retrognathia or magnitude of change between the two groups. The main significant changes in both groups were reduction of the total mandibular length, and posterior shifting in the mandible. One year after the operation the main change was the mean forward relapse of 2.5 mm in the SSO group and the mean posterior relapse of 0.5 mm in the VSO group. The difference in skeletal stability between the groups was significant (P< 0.05), and we conclude that VSO is the more effective technique for correcting mandibular prognathism.

The aim of this in vitro study was to compare fluoride release from two cement disc models (partially varnished and unvarnished) of three orthodontic bonding materials with fluoride release from the same materials when used to bond an orthodontic bracket onto a tooth surface. A resin-modified glass ionomer cement (Vitremer) and a compomer material (Dyract Ortho) were compared with a conventional resin adhesive (Right-On). Ten discs (3.0 mm diameter and 1.5 mm thick) of each material were manufactured in a silicone mould and ten premolar teeth were bonded with orthodontic brackets using each material. All the premolar teeth were covered with nail varnish up to the bracket periphery and five of the discs for each material were coated with nail varnish on both upper and lower surfaces which halved the surface area. The fluoride released into 2 ml of deionised water, from each tooth or disc, was measured at regular intervals over 60 days. At 60 days, cumulative fluoride release was highest from the unvarnished discs, less for the varnished discs and least from the tooth-bracket model for both test materials. Despite having twice the surface area, the unvarnished disc model released only 1.2 to 1.5 times more fluoride than the varnished disc model. Compared with the tooth-bracket model, the unvarnished discs released 3.0 to 4.5 times more fluoride, whereas the varnished discs released only 2.2 to 3.7 times more fluoride. For the materials tested in this study, halving the surface of the discs did not reduce the cumulative fluoride release by half. The tooth/bracket model with minimal bonding material demonstrated substantial cumulative fluoride release. The pattern of fluoride release was similar for all models tested.

The aim of this audit was to evaluate orthodontic treatment eligibility among new patients referred for assessment from primary dental care clinics in the Health Service Executive (HSE) South region to a HSE orthodontic referral centre.A data collection form was designed and applied prospectively to consecutive new patient referrals who attended diagnostic clinics at the Orthodontic Unit, Cork University Dental School and Hospital, between October 2011 and February 2012. Orthodontic treatment eligibility was based on guidelines introduced by the HSE in 2007.Data on 291 patients (147 males and 144 females) with a mean age of 11.6 years (SD +/- 2.4 years; range 8-19 years) were evaluated. Of the 83 (29%) patients eligible for orthodontic treatment under the guidelines, the most commonly diagnosed malocclusion traits were a crossbite with greater than 2 mm discrepancy between retruded contact position and intercuspal position (24 patients), followed by an overjet greater than 9 mm (21 patients).A total of 29% of new patient referrals were deemed eligible for orthodontic treatment under HSE eligibility guidelines introduced in 2007. Reduction of new patient referrals not eligible for treatment, under these guidelines, is required to enable more efficient use of resources.

To evaluate the case profile and verify the treatment eligibility (based on the modified IOTN) from written case records, of patients accepted for orthodontic treatment from the North Cork area of HSE South.A data collection form was designed and applied to the written case records of 200 consecutive patients accepted for orthodontic treatment in 2009/2010. Data relating to the IOTN (DHC and AC, where relevant) were provided by a calibrated examiner.Based on the written case records, most (57%) of the treatment cohort were female and had an average age of 14 years and two months. The predominant malocclusion was Class II division 1 (40%). The prevalence of Class III malocclusion was high at 18%. A total of 61% of patients were in grade 5 and 36% in grade 4. The majority of patients in each of these grades fell into DHC 5a (32%), followed by 5i (24%) and 4d AC8 (16%).Written case records conclude that patients accepted for orthodontic treatment from the North Cork area of HSE South were predominantly female. Class II division 1 malocclusion was the most common accepted for treatment. These records verify that those patients accepted for orthodontic treatment satisfy the eligibility criteria for HSE treatment.