Introduction: Although self-ligating brackets presumably provide better hygiene conditions, no consensus has been reached so far. Objective: Therefore, the objective of this study was to evaluate, in an in vitro experimental design, the adherence of Streptococcus mutans (SM) in self-ligating and conventional brackets of different manufacturers and ligature types. Methods: Four commercial brands of maxillary premolar metal brackets were tested (Abzil®; Morelli®; 3M Unitek®; and GAC®). Each one was subdivided into three groups, which varied according to the type of ligature and bracket model (metallic, elastic, and self-ligating), totalizing twelve groups, composed of six brackets each. Previously sterilized brackets were initially immersed in saliva for one hour, and subsequently washed and added in a bacterial suspension, maintained in aerobiosis for 72 hours. The adhered bacteria were then separated and quantified by colony forming units (CFU/mL) counting after 48 hours of growth. The groups were compared by Kruskal-Wallis and Dunn post-hoc tests (p< 0.05). Results: Regardless of the commercial brand, self-ligating brackets had significantly less CFU/mL. However, according to comparisons performed within each commercial brand, only Abzil® self-ligating brackets had significantly lower biofilm adhesion. Among all of the self-ligating models, GAC® brackets presented the highest bacterial adhesion rate. Conclusions: Self-ligating brackets are likely to present lower rates of biofilm adhesion. Particularly, Abzil® and GAC® self-ligating brackets are less likely to accumulate biofilm. Although such results are derived from an in vitro study, practitioners might acknowledge findings concerning bacterial adhesion as one of the relevant features to be considered during bracket selection.

To compare the condyle sagittal position of class I and class II division 2 in orthodontic patients. Fifty orthodontic cases (30 females and 20 males; 12-31 years) from the records of an Orthodontic Graduate Program were collected. Such cases presented cone-beam computed tomography (CBCT) as part of their initial diagnostic examinations. The study sample constituted two groups, i.e. class I and class II division 2 groups. A previously calibrated examiner performed the measurements of the images, representing the distance between the condyle and the articular surface of the glenoid fossa, both anteriorly (anterior disk space-ADS) and posteriorly (posterior disk space-PDS). Descriptive statistics were performed. Data were normally distributed, and parametric tests were used. Paired sample test was used to identify differences between the right and the left joints. Differences between class I and class II/2 groups were tested using independent t test. All statistical tests were interpreted at 5% significance level. When the study groups were compared in relation to the dimensions observed for the right and the left ADS and PDS, no significant differences were detected. This study also calculated the differences between right and left disk spaces within the groups, and the differences were not significant for both class I and class II/2 groups. The results demonstrated, after the performance of a CBCT comparative analysis, that there is no significant difference between class II/2 and class I orthodontic patients in relation to the condyle sagittal position. The results collected here refute the expectation of spontaneous mandibular anterior repositioning after correcting the overbite in class II/2 patients.