Comparative assessment of dental and basal arch dimensions of passive and active self-ligating versus conventional appliances : A randomized clinical trial.

PURPOSE: In this parallel, three-arm, single-center randomized trial, the dental and basal arch dimensions after orthodontic treatment using conventional brackets and passive and active self-ligating (SL) brackets were compared. METHODS: Patients needing comprehensive orthodontic treatment were randomly allocated to the active SL, passive SL, or conventional brackets (control) group. All patients were treated with a standardized arch wires sequence. Eligibility criteria included class I malocclusion in the permanent dentition, crowding (4-6 mm), and adequate oral hygiene. The primary outcome was intermolar width, based on cone beam computed tomography (CBCT) scans. Secondary outcomes were maxillary and mandibular widths in the canines and premolars regions, dental arch depth, buccolingual inclination, and alignment duration. Blinding of outcome assessment was implemented. Patients were followed every 4 weeks until insertion of the stainless steel 0.019â€¯× 0.025 wire. Mean values were computed from CBCT sections, and data were analyzed using a one-way analysis of variance. RESULTS: In all, 66 patients (ages 18-25 years) were randomized into a 1:1:1 ratio; 7 patients dropped out before treatment initiation. Examining dental arch dimensions in the canine and premolar regions showed that expansion of the maxillary dental arch was greatest in the passive SL brackets group, less in the active SL brackets group, and lowest in the control group (P < 0.01). Changes in maxillary intermolar width between the three groups were not significant, and changes in basal arch dimensions, depth of dental and basal arches, buccolingual inclination, and alignment duration were similar in the three groups. CONCLUSIONS: Self-ligating brackets were not more effective than conventional brackets when examining intermolar width, basal transverse dimensions, depth of the arch, and alignment duration.

Effect of fluoride-releasing resin composite in white spot lesions prevention: a single-centre, split-mouth, randomized controlled trial.

INTRODUCTION: The objective of this two-arm split-mouth randomized trial, was to evaluate the ability of fluoride-releasing resin composite to prevent demineralization and white spot lesion (WSL) formation, during orthodontic treatment with fixed appliances. METHODS: Patients needing comprehensive orthodontic treatment were randomly allocated into two groups, according to the half split-mouth technique. This trial examined a total of 300 teeth in each group: the control group, in which brackets were fixed with a non-fluoride-containing adhesive resin; and the intervention group, in which brackets were fixed with a fluoride-containing adhesive resin. Eligibility criteria included Class I malocclusion in the permanent dentition, adequate oral hygiene and no missing teeth, active caries, enamel demineralization, fluorosis staining, or heavy restorations. The primary outcome was the formation of WSLs. Randomization was achieved using a computer-generated random number table; blinding of the patients, assessor, orthodontist and data analysist were achieved. The patients were followed for twelve months, during which time their teeth were checked every three months. To investigate the differences in frequencies and ranks of demineralization and WSL formation between the two groups, odds ratios were computed using mixed modelling (to compensate for the clustered nature of the data) with intervention as a fixed effect and patient as a random effect. RESULTS: Thirty-four patients (ages, 13-25 years; mean age, 17.6) were randomized into a 1:1 ratio, though four patients dropped out before the start of the treatment. The percentage of the teeth showing the effects of demineralization and WSL formation, increased from 6.3% to 15% for the control group after three and twelve months, respectively, and from 3% to 16.3% for the study group, after three to twelve months, respectively. There were no significant differences between the two groups and no interaction between time and treatment group in the visual inspections (OR 0.79; 95% CI 0.52, 1.21), in DIAGNOdent examinations (OR 0.68; 95% CI 0.43, 1.06), or in photographic images (OR 0.72; 95% CI 0.46, 1.11). No serious harm was observed during the trial. LIMITATIONS: This trial was a single-centre trial, and treatment was carried out by one orthodontist. CONCLUSIONS: Fluoride-containing resin adhesive does not have the desired preventive effect to prevent demineralization and WSL formation, during orthodontic treatment with fixed appliance. REGISTRATION AND PROTOCOL: This randomized trial was not registered, and the protocol was not published before patient recruitment. FUNDING: The University of Damascus funded this trial.