Comparison of WALA ridge and dental arch dimensions changes after orthodontic treatment using a passive self-ligating system or conventional fixed appliance.

OBJECTIVE: To compare changes in WALA ridge and mandibular dental arch dimensions in orthodontic patients treated with a passive self-ligating system and conventional appliances. DESIGN: Original paper. SETTING: Orthodontic department at Inga University Center, Maringá, PR, Brazil. MATERIALS AND METHODS: Pretreatment (T1) and posttreatment (T2) dental casts of 60 patients with Class I malocclusion treated with slight to moderate crowding that were divided into two groups. Group 1: 30 patients treated with a passive self-ligating system, at a mean initial age of 17.68 years and mean treatment time of 2.31 years. Group 2: 30 patients treated with conventional appliances, at a mean initial age of 19.23 years and mean treatment time of 2.56 years. Measurements were taken using a digital caliper directly on pre and posttreatment dental casts to evaluate the transversal dimension behavior of the mandibular dental arch and the WALA ridge width. RESULTS: Self-ligating group presented an increase in WALA ridge width and mandibular transversal dimensions significantly greater than the conventional group, with the exception of intermolar cusp tip distance and intercanine WALA ridge. There was no statistically significant difference between the groups. There was also observed a significantly greater increase of the transversal buccal axis dimensions in the premolar area when compared to the WALA ridge increase in both groups. CONCLUSIONS: Treatment with a passive self-ligating system resulted in a significantly greater increase of the WALA ridge width and mandibular arch dimensions when compared to conventional appliance.

Comparison of Changes in Incisors Position in Cases Treated with Damon Self-Ligating and Conventional Fixed Appliances.

OBJECTIVE: This study aimed to compare the changes in maxillary and mandibular incisors position in cases treated with Damon self-ligating and conventional fixed appliances. METHODS: The sample comprised 51 patients with Class I malocclusion, mild to moderate crowding, treated without extractions, divided into 2 groups: Group 1 consisted of 20 patients treated with Damon self-ligating appliance, with a mean initial age of 15.00 years, treated for a mean period of 2.01 years; and Group 2 comprised 31 patients treated with conventional fixed appliances, with a mean initial age of 14.98 years, treated for a mean period of 1.81 years. The initial and final cephalograms of each patient were measured. The intergroup comparisons were performed with independent t or Mann-Whitney tests. RESULTS: Both groups showed a mild protrusion and a buccal inclination of the maxillary and mandibular incisors, with no statistically significant difference between them. CONCLUSION: The changes in maxillary and mandibular incisors position were similar between the groups treated with Damon self-ligating and conventional fixed appliances.