Perceptions of undertaking a higher degree alongside dental specialty training: A cross-sectional survey of UK dental specialty trainees.

INTRODUCTION: The curricula for UK dental specialty training have recently been under review and until 2024, completion of a research component during training in Dental Public Health, Oral Microbiology and Orthodontics has been mandatory (with an alternative route for Orthodontics involving the submission of two scientific papers for those trainees not wishing to undertake a higher degree). Anecdotally, some trainees in other dental specialties choose to undertake higher degrees alongside specialty training. AIMS: The aims were to investigate how many dental specialty registrars study for higher degrees alongside specialty training, and whether undertaking a higher degree alongside specialty training has an impact on completion of training, research skills, research experience, patient care and career opportunities. MATERIALS AND METHODS: This was a cross-sectional study design, involving the distribution of an online, anonymous questionnaire-based survey to UK dental specialty registrars in November and December 2022. RESULTS: In total, 38 questionnaires were completed, representing a 7.7% response rate of the entire dental specialty registrar cohort in the UK and 42% of those who received it. Most respondents (76.3%) were either studying or had completed a clinically relevant higher degree prior to specialty training. Most respondents (76.3%) reported that the higher degree increased career opportunities and gave them additional skills. CONCLUSIONS: Dental specialty trainees who responded to this survey perceived the higher degree to be beneficial in terms of preparing for exams, gaining skills in critical appraisal and for increasing future career opportunities.

Duration of tooth alignment with fixed appliances: A systematic review and meta-analysis.

INTRODUCTION: A key goal of orthodontic treatment with fixed appliances is alignment of the dentition, and this remains a commonly selected outcome in clinical studies investigating orthodontic tooth movement. This systematic review has evaluated treatment duration to achieve alignment of the mandibular dentition using fixed appliances. METHODS: Systematic literature searches without restrictions were undertaken in 9 databases for randomized clinical trials (RCTs) assessing duration and rate of tooth alignment using fixed appliances with or without treatment adjuncts published up to January 2021. After duplicate study selection, data extraction, and risk of bias assessment according to Cochrane, random-effects meta-analyses of aggregate data, and individual patient data were conducted. RESULTS: Thirty-five trials were included with 2258 participants (39% male; mean age 17.8 years), giving a pooled duration to achieve whole-arch alignment of the mandibular dentition of 263.0 days (4 trials; 95% confidence interval [CI], 186.7-339.4 days) and incisor alignment in the mandibular arch of 100.7 days (9 trials; 95% CI, 84.1-117.4 days). Surgical-assisted orthodontics was associated with reduced duration of incisor alignment: mean difference of 44.3 days less (4 trials; 95% CI, 20.0-68.9 days; P <0.001; high quality of evidence), whereas subgroup and meta-regression analyses indicated significant effects of baseline crowding and premolar extractions. Individual patient data analysis from 3 RCTs indicated that for each additional participant age year, whole-arch alignment of the mandibular dentition took 13.7 days longer (3 trials; 95% CI, 7.7-17.7 days; P <0.001) and for each additional mm of irregularity, 17.5 days more were needed (2 trials; 95% CI, 9.8-25.2 days; P <0.001). CONCLUSIONS: Patient and treatment-related characteristics can significantly affect the duration of tooth alignment and should be taken into account both clinically and when designing trial outcomes. Future research studies investigating rates of orthodontic tooth alignment would benefit from adequate sample sizes and a more consistent methodology in outcome assessment. Data in this systematic review provides a basis for appropriate trial design for future RCTs investigating the rate of orthodontic tooth alignment with fixed appliances.

Microbial colonisation associated with conventional and self-ligating brackets: a systematic review.

BACKGROUND: Decalcification and gingivitis caused by plaque accumulation around brackets are common iatrogenic effects of fixed appliances. The influence of conventional versus self-ligating bracket design on microbial colonisation is unknown. OBJECTIVE: To assess the levels of microbial colonisation associated with conventional and self-ligating brackets. SEARCH SOURCES: Three databases were searched for publications from 2009 to 2021. DATA SELECTION: Randomised controlled trials comparing levels of microbial colonisation before and during treatment with conventional and self-ligating brackets were assessed independently and in duplicate. DATA EXTRACTION: Data were extracted independently by two authors from the studies that fulfilled the inclusion criteria. Risk of bias assessments were made using the revised Cochrane risk of bias tool for randomized trials. The quality of the included studies was assessed using the Critical Appraisal Skills Programme Checklist. RESULTS: A total of 11 randomised controlled trials were included in this systematic review. Six of the studies were found to be at low risk of bias and five presented with some concerns. The studies were considered moderate to high quality. Five trials reported no statistically significant difference in microbial colonisation between bracket types. The remaining studies showed mixed results, with some reporting increased colonisation of conventional brackets and others increased colonisation of self-ligating brackets. The heterogeneity of study methods and outcomes precluded meta-analysis. CONCLUSION: Of the 11 studies included in this systematic review, five found no differences in colonisation between conventional and self-ligating brackets. The remaining studies showed mixed results. The evidence is inconclusive regarding the association between bracket design and levels of microbial colonisation.

Patient reported experiences and treatment outcomes of orthodontic patients treated within secondary care settings in the South West of England during the COVID-19 pandemic.

OBJECTIVE: To assess the impact of the temporary cessation of orthodontic services on patients undergoing treatment during the COVID-19 pandemic. DESIGN: Two-phase multicentre service evaluation. SETTING: Secondary care orthodontic departments in the South West of England. MATERIALS AND METHODS: Phase 1 - Patient-Reported Experience Measure questionnaire (PREM). The questionnaire was distributed to patients who had undergone orthodontic treatment during the COVID-19 pandemic once services had resumed. Phase 2 - assessment of treatment outcomes, specifically with the Peer Assessment Rating (PAR) Index. A total of 280 PAR scores were obtained from a cohort of patients treated before and during the pandemic. RESULTS: A total of 711 PREM questionnaires were completed. Participants generally felt relaxed when visiting secondary care settings, orthodontic departments and whilst wearing orthodontic appliances during the pandemic. Nearly 40% of participants were concerned that the pandemic would impact on their treatment, particularly treatment length. Treatment outcomes revealed that patients treated before and during the pandemic experienced percentage PAR score reductions of 83.9% and 80.6%, respectively. Patients receiving treatment during the pandemic experienced longer treatment durations of 126 days. CONCLUSION: During the pandemic, low levels of anxiety were reported with respect to receiving orthodontic treatment in secondary care settings. Irrespective of the pandemic, a high standard of orthodontic treatment was provided. However, patient concerns regarding treatment length were justified.

Educational Attainment of Children Born with Unilateral Cleft Lip and Palate in the United Kingdom.

OBJECTIVE: This study evaluated association between functional outcomes in children born with unilateral cleft lip and palate (UCLP) and educational attainment. DESIGN: Cleft Care UK (CCUK) was a United Kingdom (UK) wide cross-sectional study. SETTING: UK Cleft Teams (data collected from all UK sites providing centralized cleft services). PATIENTS, PARTICIPANTS: Five-year olds born with nonsyndromic UCLP (n = 268). MAIN OUTCOME MEASURE(S): National tests for educational attainment Key Stage 1 (KS1) undertaken by children at age 7 were linked to CCUK data to describe differences in educational attainment. Associations between functional outcomes and KS1 results were evaluated using regression analysis. We adjusted for birth month, gender, and an area-based measure of socioeconomic status. RESULTS: Data were available for 205 children with UCLP. These children scored lower than national average (NA) scores across all subject areas, with a 0.62 lower score observed in the Average Point Score (APS; P = .01). There was association between being in a lower category for a cleft related outcomes and poorer KS1 results, with a trend for poorer attainment with higher numbers of poor functional outcomes. Those with 3 or more poor outcomes had a -2.26 (-3.55 to -0.97) lower APS compared to those with 0 to 1 poor outcomes. CONCLUSIONS: Children born with UCLP have poorer educational attainment at age 7 across all subject areas though differences were modest. Children with poor functional outcomes at age 5 had worse educational outcomes age 7. Improvements in functional outcomes could enhance educational outcomes.

Is There a Correlation Between Nasolabial Appearance and Dentoalveolar Relationships in Patients With Repaired Unilateral Cleft Lip and Palate?

OBJECTIVE: To determine whether a relationship exists between the aesthetic scores given to photographic records of the nasolabial region of patients with repaired unilateral cleft lip and palate (UCLP) and the 5-Year Olds' Index scores of study models for the same participants. DESIGN: Retrospective study. SETTING: University of Bristol Dental Hospital, United Kingdom. PARTICIPANTS: Patients with nonsyndromic UCLP previously enrolled in the Cleft Care UK (CCUK) Study. METHODS: The CCUK participants, who had both study models and photographs (frontal and worm's eye view), were identified and their records retrieved. These were rated by 2 consultants and 2 senior registrars in orthodontics. The 5-Year Olds' Index was used to score the study models, and at a separate sitting, a 5-point Likert scale was used to score the cropped frontal and worm's eye view photographs of the same children. The results were analyzed using intraclass correlation coefficients and Cohen κ. MAIN OUTCOME MEASURES: Correlation between the aesthetic scores of the photographic views and the concordant 5-Year Olds' Index scores of the study models. RESULTS: The intraclass correlation coefficient scores showed very poor agreement between the photographic views and their concordant study models. The level of inter- and intra-rater reliability was strongest when scoring the study models. CONCLUSIONS: There was no agreement between the scores given to various photographic views and their corresponding study models. Scoring the study models using the 5-Year Olds' Index was the most reliable outcome measure for this age-group.

Chlorhexidine hexametaphosphate as a coating for elastomeric ligatures with sustained antimicrobial properties: A laboratory study.

INTRODUCTION: White spot lesions are a common side effect of orthodontic treatment. This laboratory study aimed to explore the suitability of chlorhexidine hexametaphosphate (CHX-HMP) as a coating for orthodontic elastomeric ligatures to provide sustained chlorhexidine (CHX) release. METHODS: Dissolution kinetics of CHX-HMP were firstly explored using spectroscopy and a colorimetric phosphate assay. Elastomeric ligatures were categorized into 3 groups-acetone-conditioned, ethanol-conditioned, and as received-and were then immersed in 5 mM CHX-HMP suspension or 5 mM chlorhexidine digluconate solution and rinsed. CHX release was measured over 8 weeks, and the effects of conditioning and immersion on elastomeric force and extension at rupture and surface topography were investigated. RESULTS: CHX-HMP exhibited a gradual equilibration that had not reached equilibrium within 8 weeks, releasing soluble CHX and a mixture of polyphosphate and orthophosphate. CHX digluconate-treated ligatures showed no CHX release, whereas CHX-HMP-treated ligatures showed varying degrees of release. As received, CHX-HMP-treated ligatures showed a modest release of CHX up to 7 days. Acetone conditioning did not enhance CHX-HMP uptake or subsequent CHX release and caused a deterioration in mechanical properties. Ethanol conditioning enhanced CHX-HMP uptake (6×) and led to a sustained CHX release over 8 weeks without affecting mechanical properties. CONCLUSIONS: Within the inherent limitations of this in-vitro study, CHX-HMP led to a sustained release of CHX from orthodontic elastomeric ligatures after ethanol conditioning. Conditioned and coated elastomeric ligatures may ultimately find application in the prevention of white spot lesions in orthodontic patients.

The use of attachments in aligner treatment: Analyzing the "innovation" of expanding the use of acid etching-mediated bonding of composites to enamel and its consequences.

Orthodontic treatment with sequential aligners has seen a considerable surge in the last decades, and is currently used to treat malocclusions of varying severity. To enhance tooth movement and broaden the spectrum of malocclusions that can be treated with aligners, composite resin attachments are routinely bonded with the acid-etch technique on multiple teeth, a process known to impose irreversible alterations of the enamel structure, color, gloss, and roughness. Additionally, this clinical setting introduces a unique scenario of different materials applied in a manner that involves the development of friction and attrition between the attachment and the softer aligner material, all performing in the harsh conditions of the oral environment, which impact the aging of these materials. The latter may give rise to alterations of the aligners and the composite attachments and potential intraoral release of Bisphenol A, a known endocrine disrupting agent. Furthermore, at the final stages of contemporary aligner treatment, the removal of multiple, sometimes bulky, composite attachments with a volume and surface far greater than the remnant adhesive after debonding of brackets, through grinding that might be associated with pulmonary effects for the patient or staff. Because of the extensive enamel involvement in bonding, the release of factors from the attachment-aligner complex during service, the aging of these entities in the oral environment, and the laborious debonding/composite grinding process coupled with the hazardous nature of aerosol produced during the removal of these bulky specimens, appropriate risk management considerations should be applied and an effort to confine the application of multiple composite specimens bonded to enamel to the absolutely necessary should be pursued.

Experiences of mentoring ST4-ST5s amongst a group of orthodontic trainers at Bristol Dental School and Hospital.

OBJECTIVE: To explore the experiences of mentoring higher-grade trainees amongst senior orthodontic trainers at Bristol Dental School. DESIGN: Qualitative study using interpretive methodology. SETTING: University of Bristol Dental School. PARTICIPANTS: Six consultant orthodontists, five of whom also have district general hospital experience. METHODS: One-to-one semi-structured interviews were undertaken on a purposeful sample of orthodontic trainers. The interviews were audio recorded, transcribed verbatim and Thematic Analysis was used to analyse the data. RESULTS: Four main themes emerged from the data were. They were: How to Mentor; Mentor-Mentee Pairings; Resources and Success; and Pitfalls of Mentoring. CONCLUSION: The present study revealed that senior trainers have a good understanding of the qualities of a mentor and appreciate the roles which mentors need to perform. They are altruistic in their motives, but would benefit from more time, organisational support and training to help them perform their duties better.

Outcome Measures in UCLP: The Modified 5-Year-Olds'-Index-Development and Reliability.

OBJECTIVE: Can we reliably discriminate severity within the existing categories of the 5-Year-Olds' Index? DESIGN: Retrospective method comparison and development study. SETTING: School of Oral and Dental Science, University of Bristol. METHODS: Dental study models of 5-year-olds with unilateral cleft lip and palate (UCLP) were collected from the archives of 2 national cleft surveys (n = 351). One hundred randomly selected models were ranked to construct the modified 5-Year-Olds' Index and also scored using a visual analogue scale (VAS). Reliability testing was performed on 51 study models. Visual analogue scale scores were used to aid statistical analysis and investigate the reliability of a VAS for outcome measurement. The modified 5-Year-Olds' Index was then applied to 198 study models of 5-year-olds with UCLP. RESULTS: The modified 5-Year-Olds' Index showed excellent intra and interexaminer agreement (intraclass correlation > 0.94) and good discrimination of severity. When applied to the Cleft Care UK participants (n = 198), the modified 5-Year-Olds' Index showed good discrimination of severity within the better categories (groups 1-3) of the 5-Year-Olds' Index. Visual analogue Scale scores resulted in unacceptable variation between measurements. CONCLUSIONS: The new modified 5-Year-Olds' Index is a reliable method of assessing outcomes at 5 years of age and showed improved discriminatory power between the "better" outcome categories than the original 5-Year-Olds' Index. A VAS was found to be unsuitable for assessing outcome at 5 years of age for children with UCLP.

Particulate production during debonding of fixed appliances: Laboratory investigation and randomized clinical trial to assess the effect of using flash-free ceramic brackets.

INTRODUCTION: The aim of this laboratory and randomized clinical trial was to investigate particulate production at debonding and enamel clean-up following the use of flash-free ceramic brackets and to compare them with non-flash-free metal and ceramic brackets. METHODS: In the laboratory study, brackets were bonded to bovine teeth. After 24 hours of immersion in water, the brackets were debonded, the adhesive remnant scores noted, and the enamel cleaned with the use of rotary instruments. Four bracket-adhesive combinations and 2 different enamel pretreatment regimens were tested, including metal and ceramic brackets (conventional, adhesive precoat [APC], and APC flash-free) and conventional acid etch and self-etching primer. Quantitative (mg/m3) and qualitative analysis of particulate production was made in each case. In the clinical trial, 18 patients treated with the use of fixed appliances were recruited into this 3-arm parallel-design randomized controlled trial. They were randomly allocated to 1 of 3 groups: experimental flash-free ceramic bracket or non-flash-free ceramic or metal bracket group. Eligibility criteria included patients undergoing nonextraction maxillary and mandibular fixed appliance therapy. At completion of treatment, the brackets were debonded, and the primary outcome measure was particulate concentration (mg/m3). Randomization was by means of sealed envelopes. Data were analyzed with the use of quantile plots and linear mixed models. The effect of etch, bracket, and stage of debonding of clean-up on particle composition was analyzed with the use of mixed-effects regression. RESULTS: In the laboratory study, the APC brackets produced the highest particulate concentration. Although statistically significantly higher than the metal and conventional ceramic brackets, it was not significantly higher than the ceramic flash-free brackets. In the clinical study, there was no statistically significant effect of bracket type on particulate concentration (P = 0.29). This was despite 3 patients with APC flash-free and 1 patient with conventional Clarity (with 1 bracket) having 1 or more ceramic bracket fracture at debonding requiring removal. No adverse events reported. CONCLUSIONS: Particulates in the inhalable, thoracic, and respirable fractions were produced at enamel clean-up with all bracket types. Although APC and APC flash-free brackets produced the highest concentrations in the laboratory study, there was no difference between any of the brackets in the clinical trial. REGISTRATION: The trial was not registered. FUNDING: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

National British Orthodontic Society (BOS) Orthognathic Audit 2017-2018.

OBJECTIVE: To carry out a UK national clinical audit of orthognathic acceptance criteria and information provided to orthognathic patients before treatment. DESIGN: National clinical audit. SETTING: Data collected using Bristol Online Surveys. PARTICIPANTS: Sixty-nine UK hospital orthodontic departments submitted data. METHODS: Data were collected at two time points using Bristol Online Surveys over a period of 12 months. These were before treatment at the first multidisciplinary clinic (MDT) and immediately after surgery. The data collected included: Index of Orthognathic Functional Treatment Need (IOFTN); Index of Orthodontic Treatment Need (IOTN); age; previous orthodontic treatment; attendance at an MDT; treatment times; and information provision. RESULTS: Eighty-five units agreed to take part in the audit with 69 submitting data, giving a response rate of 81%. The data from 3404 patients were uploaded, 2263 before treatment and 1141 immediately after surgery. Of patients, 91.07% had an IOFTN score of 4 or 5 and 88.73% had an IOTN score of 4 or 5. The mean age at the first MDT was 22 years in the first cohort and 21 years and 4 months in the second immediate post-surgery cohort. Of patients, 37.93% had undergone some form of previous orthodontic treatment, but only 0.28% had undergone previous orthognathic treatment; 96.93% had an MDT confirm that orthodontic treatment by itself was insufficient to adequately correct their functional symptoms. The average treatment time from bond up to surgery was 2 years and 6 months. With respect to information provision, patients received information from a number of sources, principally the British Orthodontic Society (BOS) patient information leaflets and the BOS website Your Jaw Surgery. CONCLUSIONS: In the UK, the majority of orthognathic cases fulfil the criteria for acceptance for NHS-funded orthognathic treatment, as outlined by the Chief Dental Officer's interim guidance on orthognathic treatment. This suggests any prior approval process would not be a good use of NHS resources in the commissioning of orthognathic treatment.

Chewing gum vs. ibuprofen in the management of orthodontic pain, a multi-centre randomised controlled trial - the effect of anxiety.

OBJECTIVES: Pain is a common side effect of orthodontic treatment. An objective of this study, part of a large previously reported RCT on pain and analgesic use, was to determine the effect of anxiety on perceived pain and use of analgesia. METHODS: 1000 patients aged 11-17 years, undergoing upper and lower fixed appliance treatment in nine hospital departments were recruited into this two-arm parallel design randomised controlled trial. One arm was given sugar-free chewing gum and the other arm ibuprofen for pain relief. Neither the clinicians nor patients were blinded to assignment. In addition to recording pain experience and analgesic use for 3 days following appliance placement and first archwire change, each patient recorded their level of anxiety immediately following the fitting of the appliance and the first archwire change. RESULTS: 419 chewing gum group (84%) and 407 ibuprofen group (83%) questionnaires were returned following appliance placement, and 343 chewing gum group (70%) and 341 ibuprofen group (71%) questionnaires were returned following the first archwire change. The mean anxiety scores following fitting of the appliance and first archwire change were 2.7 (SD 2.1) and 1.6 (SD 1.8), respectively. There were weak but significant positive associations between anxiety scores and pain scores. Multi-level modelling produced a coefficient for anxiety of 0.23 (95% CI 0.17-0.28) for appliance placement, suggesting a small rise (0.23) on the 11-point pain scale for a one-point increase on the corresponding anxiety scale. Following archwire change, the corresponding coefficient was 0.32 (0.24-0.39). For ibuprofen use, again simple analyses suggested a relationship with anxiety. Multi-level logistic modelling produced an odds ratio for ibuprofen use of 1.11 (95% CI 1.07-1.15) at appliance placement and 1.21 (1.10-1.33) at the first archwire change. There was a 10-20% increase in the odds of using ibuprofen for each one-point increase on the anxiety scale. No such relationship was found between anxiety and chewing gum use. There were no adverse effects or harms reported during the trial. Approvals were granted by the Research Ethics Committee (08/H0106/139), R&D and MHRA (Eudract 2008-005522-36) and the trial was registered on the ISRCTN (79884739) and NIHR (6631) portfolios. Support was provided by the British Orthodontic Society Foundation. CONCLUSIONS: There was a weak positive correlation between anxiety reported and pain experienced following both the initial fitting of the fixed appliances and at the subsequent archwire change. Patients that were more anxious tended to take more ibuprofen for their pain relief.

What is the truth behind the smile?

A number of arguments surround orthodontics and orthodontic treatment and this article aims to discuss the current thinking and evidence base associated with these controversies.

Microbiological assessment of aerosol generated during debond of fixed orthodontic appliances.

INTRODUCTION: The aims of this study were to describe bacterial load and diversity of the aerosol created during enamel cleanup after the removal of fixed orthodontic appliances and to assess the effect of a preprocedural mouth rinse. METHODS: The study involved the sampling of ambient air adjacent to the patient's mouth during adhesive removal using a slow-speed handpiece and a spiral fluted tungsten carbide bur without water irrigation. Sampling was carried out during enamel cleanup with or without a preprocedural mouth rinse of either sterile water or chlorhexidine. Airborne particles were collected using a viable inertial impactor simulating the human respiratory tree. The bacteria collected were analyzed using both culture and molecular techniques. RESULTS: Bacteria produced during debond and enamel cleanup can reach all levels of the respiratory tree. The use of a preprocedural mouth rinse, either sterile water or chlorhexidine, increased the numbers and diversity of the bacteria in the air. CONCLUSIONS: When using a slow-speed handpiece and a spiral fluted tungsten carbide bur for enamel cleanup after orthodontic treatment, the bacterial load and diversity of the aerosol produced are lower when a preprocedural mouth rinse is not used.

Comparative assessment of chewing gum and ibuprofen in the management of orthodontic pain with fixed appliances: A pragmatic multicenter randomized controlled trial.

INTRODUCTION: The aim of this randomized trial was to investigate the effect of the use of a sugar-free chewing gum vs ibuprofen on reported pain in orthodontic patients. METHODS: This was a 2-arm parallel design randomized controlled trial in 9 sites in the southwest of England. Patients about to undergo orthodontic treatment with maxillary and mandibular fixed appliances were recruited and randomly allocated to an experimental chewing gum group or a control ibuprofen group. Eligibility criteria included patients undergoing fixed maxillary and mandibular appliance therapy, aged 11 to 17 years, and able to use ibuprofen and chewing gum. The primary outcome measure was pain experienced after appliance placement using a mean of 3 recordings on a scale of 0 to 10. Secondary outcome measures were pain experienced in the subsequent 3 days, pain after the first archwire change, ibuprofen use, and appliance breakages. Pain scores were recorded with a questionnaire and posted to a collection center by each patient. Randomization was by means of a central telephone service and comprised computer-generated random numbers used to generate a sequential allocation list, with permuted blocks of variable size (2 and 4) and stratified by center. Neither the clinicians nor the patients were blinded to the intervention. Patients in the control group were permitted to use ibuprofen only, and patients in the experimental group were allowed to use ibuprofen if they did not get sufficient analgesia from the chewing gum. Data were analyzed using the principle of intention to treat with multilevel modeling to reflect the structured nature of the data (scores within patient within site). RESULTS: One thousand patients were recruited and randomized in a ratio of 1:1 to the chewing gum and ibuprofen (control) groups. The male-to-female ratios were similar in the groups. The pain questionnaire response rates were good at approximately 84% and 83% after appliance placement (chewing gum group, 419; ibuprofen group, 407) and 70% and 71% after the first archwire change (chewing gum group, 343; ibuprofen group, 341). The primary outcomes were similar for the 2 groups: mean pain scores, 4.31 in the chewing gum group and 4.17 in the ibuprofen group; difference, 0.14 (95% CI, -0.13 to 0.41). There was a suggestion that the relative pain scores for the 2 groups changed over time, with the chewing gum group experiencing slightly more pain on the day of bond-up and less on the subsequent 3 days; however, the differences had no clinical importance. There were no significant differences for the period after archwire change. The reported use of ibuprofen was less in the chewing gum group than in the ibuprofen group; after appliance placement, the mean numbers of occasions that ibuprofen was used were 2.1 in the chewing gum group and 3.0 in the ibuprofen group (adjusted difference, -0.96 [95% CI, -0.75 to -1.17; P <0.001]); after archwire change, the figures were 0.8 and 1.5 occasions (difference, -0.65 [-0.44 to -0.86; P <0.001]). After appliance placement and the first archwire change, there was no clinically or statistically significant difference in appliance breakages between the chewing gum and ibuprofen groups after either bond-up (7% and 8.8%, respectively) or the first archwire change (4.2% and 5.5%, respectively). No adverse events were reported. CONCLUSIONS: The use of a sugar-free chewing gum may reduce the level of ibuprofen usage but has no clinically or statistically significant effect on bond failures. REGISTRATION: International Standard Randomised Controlled Trial Number (79884739) and National Institute of Health Research (6631) portfolios. FUNDING: This research was supported by an award by the British Orthodontic Society Foundation.

Does a true knowledge of dental crowding affect orthodontic treatment decisions?

OBJECTIVES: To assess whether a true knowledge of crowding alters treatment decisions compared with estimates of crowding. MATERIALS AND METHODS: Thirty-six orthodontists were asked to estimate crowding using visualization on eight mandibular arch study models and to indicate possible extraction choices. For each model, the intermolar widths, intercanine widths, and clinical scenarios were identical, but the true crowding varied from 0.2 to 8.4mm as to a lesser extent did the curve of Spee. Eleven orthodontists repeated the visualization exercise after 2 weeks to assess reliability. All 36 of the orthodontists were asked to repeat the treatment planning exercise on the same models, but this time was provided with the true amount of crowding in each case. RESULTS: When the 36 orthodontists used direct visualization of the models to assess crowding, the range of their estimates of crowding increased as the crowding increased. As might be expected, they also tended to move towards extraction treatments as the crowding increased (P = 0.013, odds ratio = 3). Although the reliability of the repeat estimates of crowding were moderate, the mean estimates were greater than the true crowding for each model. When orthodontists were presented with the true amount of crowding, rather than their estimate of crowding, it had a significant effect on the decision to extract, with fewer orthodontists recommending extractions. LIMITATIONS: The principal limitation of this study is that it was a laboratory-based study and utilized just the mandibular arch model for estimation and treatment planning. CONCLUSIONS: Direct visualization may overestimate the amount of crowding present. When the true amount of crowding is known, it can lead to more consistent treatment planning, with the decision to extract fewer teeth in the borderline cases. A formal space analysis is likely to assist with treatment planning.

Axenic culture of a candidate division TM7 bacterium from the human oral cavity and biofilm interactions with other oral bacteria.

The diversity of bacterial species in the human oral cavity is well recognized, but a high proportion of them are presently uncultivable. Candidate division TM7 bacteria are almost always detected in metagenomic studies but have not yet been cultivated. In this paper, we identified candidate division TM7 bacterial phylotypes in mature plaque samples from around orthodontic bonds in subjects undergoing orthodontic treatment. Successive rounds of enrichment in laboratory media led to the isolation of a pure culture of one of these candidate division TM7 phylotypes. The bacteria formed filaments of 20 to 200 µm in length within agar plate colonies and in monospecies biofilms on salivary pellicle and exhibited some unusual morphological characteristics by transmission electron microscopy, including a trilaminated cell surface layer and dense cytoplasmic deposits. Proteomic analyses of cell wall protein extracts identified abundant polypeptides predicted from the TM7 partial genomic sequence. Pleiomorphic phenotypes were observed when the candidate division TM7 bacterium was grown in dual-species biofilms with representatives of six different oral bacterial genera. The TM7 bacterium formed long filaments in dual-species biofilm communities with Actinomyces oris or Fusobacterium nucleatum. However, the TM7 isolate grew as short rods or cocci in dual-species biofilms with Porphyromonas gingivalis, Prevotella intermedia, Parvimonas micra, or Streptococcus gordonii, forming notably robust biofilms with the latter two species. The ability to cultivate TM7 axenically should majorly advance understanding of the physiology, genetics, and virulence properties of this novel candidate division oral bacterium.

Comparative assessment of alignment efficiency and space closure of active and passive self-ligating vs conventional appliances in adolescents: a single-center randomized controlled trial.

INTRODUCTION: The aim of this study was to compare the time to initial alignment and extraction space closure using conventional brackets and active and passive self-ligating brackets. METHODS: One hundred adolescent patients 11 to 18 years of age undergoing maxillary and mandibular fixed appliance therapy after the extraction of 4 premolars were randomized with stratification of 2 age ranges (11-14 and 15-18 years) and 3 maxillomandibular plane angles (high, medium, and low) with an allocation ratio of 1:2:2. Restrictions were applied using a block size of 10. Allocation was to 1 of 3 treatment groups: conventional brackets, active self-ligating, or passive self-ligating brackets. All subjects were treated with the same archwire sequence and space-closing mechanics in a district general hospital setting. The trial was a 3-arm parallel design. Labial-segment alignment and space closure were measured on study models taken every 12 weeks throughout treatment. All measurements were made by 1 operator who was blinded to bracket type. The patients and other operators were not blinded to bracket type during treatment. RESULTS: Ninety-eight patients were followed to completion of treatment (conventional, n = 20; active self-ligating brackets, n = 37; passive self-ligating brackets, n = 41). The data were analyzed using linear mixed models and demonstrated a significant effect of bracket type on the time to initial alignment (P = 0.001), which was shorter with the conventional brackets than either of the self-ligating brackets. Sidak's adjustment showed no significant difference in effect size (the difference in average response in millimeters) between the active and passive self-ligating brackets (the results are presented as effect size, 95% confidence intervals, probabilities, and intraclass correlation coefficients) (-0.42 [-1.32, 0.48], 0.600, 0.15), but the conventional bracket was significantly different from both of these (-1.98 [-3.19, -0.76], 0.001, 0.15; and -1.56 [-2.79, -0.32], 0.001, 0.15). There was no statistically significant difference between any of the 3 bracket types with respect to space closure. Space-closure times were shorter in the mandible, except for the Damon 3MX bracket (Ormco, Orange, Calif), where active and total space-closure times were shorter in the maxilla. No adverse events were recorded in the trial. CONCLUSIONS: Time to initial alignment was significantly shorter for the conventional bracket than for either the active or passive self-ligating brackets. There was no statistically significant difference in passive, active, or total space-closure times among the 3 brackets under investigation.

How good are we at estimating crowding and how does it affect our treatment decisions?

OBJECTIVES: To assess the estimation of crowding by orthodontists and their subsequent extraction choices. MATERIALS AND METHODS: Sixty-two orthodontists were asked to quantify crowding on eight lower arch study models using their preferred method and also to indicate possible extraction choices. For each model, the intermolar widths, intercanine widths, and clinical scenarios were identical, but the true crowding varied from 0.1 to 7.5mm across the eight models as to a lesser extent did the curve of Spee. Eleven orthodontists repeated the exercise after 9 months to assess reliability. RESULTS: The preferred method of space estimation by all of the orthodontists was direct visualization. However, the estimates of crowding were very variable. For the most crowded lower model with 7.5mm of crowding, the estimates ranged from 5 to 20mm. Extraction choices were less variable than estimates of crowding and shifted from second to first premolars as crowding increased. Estimates of crowding and treatment decisions changed with time in 28 of 33 repeat measures. Estimates of crowding were unrelated to clinical experience. LIMITATIONS: The principal limitation of this study is that it was a laboratory-based study and utilized just the lower arch model for estimation and treatment planning. CONCLUSIONS: Extraction decisions and estimates of crowding tended to vary both initially and over time but were less varied in the case of the extraction decisions. Although this may have been a reflection of the limited treatment options, perhaps reassuringly, as the degree of crowding increased, so did the likelihood of prescribing extractions and the decisions generally shifted from second to first premolars. How orthodontists estimate crowding and make subsequent extraction choices is important and has potential medico-legal implications.