Dentoskeletal and soft-tissue changes of class II malocclusion treatment with modified first class appliances: a prospective clinical trial.

BACKGROUND/OBJECTIVES: Intraoral distalizers are effective and conservative alternatives for Class II malocclusion treatment. However, the literature is still controversial regarding the effects of using skeletal anchorage in intraoral distalizers with different designs. The aim of this study is to compare dentoskeletal and soft-tissue changes of Class II malocclusion patients treated with three types of First Class (FC) distalizers. MATERIALS/METHODS: The sample of this prospective clinical trial included 30 consecutive patients divided into three groups: G1-FC conventionally anchored; G2-FC skeletally anchored Type 1; G3-FC skeletally anchored Type 2. Each group consisted of 10 patients. Lateral cephalograms were analyzed in two stages: at pre-treatment (T0) and after distalization (T1). The radiographs were digitized and analyzed using the software Dolphin Imaging 11.5. Comparisons of treatment changes between groups (T1-T0) were performed using one-way analysis of variance (ANOVA), followed by the Tukey test. RESULTS: Patients treated with the conventionally anchored FC showed significantly greater incisors protrusion and labial inclination, second premolars mesial inclination and mesialization than the FCs skeletally anchored. No differences were observed regarding the amount of molar distalization and molar angulation between groups. LIMITATIONS: It can be considered that the limitation of this study lies in its non-randomized design. CONCLUSIONS/IMPLICATIONS: First Class distalizers with conventional and skeletal anchorage are effective alternatives for Class II molar distalization. Distalization associated with indirect skeletal anchorage reduce the undesirable effects observed in the incisors and premolars during distalization when compared to distalization conventionally anchored.

Teeth angulations after class II treatment with the Jones Jig followed by fixed appliances: A retrospective panoramic analysis.

OBJECTIVE: The purpose of this study was to compare the maxillary mesiodistal dental angulations of Class II malocclusion patients treated with the Jones Jig, followed by fixed appliances, with normal values of a historical control group, on panoramic radiographs. MATERIAL AND METHODS: The sample comprised 80 panoramic radiographs of 40 patients divided into two groups. Eligibility criteria included patients with predominantly dental Class II malocclusion; the presence of all teeth up to the second molars and no previous orthodontic treatment. The experimental group was composed of 60 radiographs of 20 patients treated with the Jones Jig distalizer followed by fixed appliances. The radiographs were taken at pre-treatment (T0), post-distalization (T1), and post-treatment (T2). The historical control group comprised 20 radiographs of 20 subjects with untreated normal occlusion. The mesiodistal axial angulations of all maxillary erupted teeth were evaluated with the Dolphin Imaging software. Intragroup comparisons in the experimental group were performed with repeated measures analysis of variance (ANOVA), followed by Tukey tests. The experimental group at T2 versus the control group were compared with t tests. RESULTS: After distalization, significant distal angulation of the molars (110.58°±8.54, P<0.000) and mesial angulation of the second (86.43°±8.08, P<0.000) and first premolars (80.11°±8.01, P<0.000) was observed. However, this was corrected after comprehensive fixed orthodontics (100.54°±6.53; 98.95°±7.00; 94.92°±6.44; P<0.000, for these teeth, respectively). Intergroup comparisons resulted in first molars, premolars, canines, and central incisors significantly more distally angulated in the experimental group, when compared to the control. CONCLUSIONS: In general, at the end of orthodontic treatment, patients treated with the Jones Jig distalizer followed by fixed appliances presented more distally angulated maxillary teeth when compared to an untreated group with normal occlusion.