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.

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.

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.

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.

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.

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.