Aim of the study: The objective of this study was to evaluate the skeletal and dental effects of intermaxillary Class III elastics using bone anchored miniplates compared to an untreated Class III control group.
Subjects and methods: 24 subjects (14 females and 10 males) having skeletal Class III malocclusion with maxillary deficiency with an age range of 8-11 years old were divided into two groups 12 patients each (n=12). Group A constituted treatment with Class III elastics anchored to
4 titanium miniplates, 2 anchored in the zygomatic buttress of the maxilla and 2 miniplates anchored in the symphyseal region of the mandible at the lateral/canine region. Group B (n=12) constituted untreated skeletal Class III cases (control group). The treatment and observation periods for both groups were 8 months. Lateral cephalometric radiographs were taken for the patients at start of treatment (T1) and at the end of the treatment/observation periods (T2). The radiographs were analyzed by performing lateral cephalometric analysis. Independent student t test was done to compare variables between the two groups.
Results: There was correction of the skeletal Class III in the miniplates group with statistically significant increase in angle SNA (mean 3.50° ± 0.68), A-Nperp (mean 4.04mm ± 1.20), ANB (mean 4.06◦±0.95) and Witts appraisal (mean 4.91mm ± 1.76) .Slight mandibular retrusion occurred with a reduction in angle SNB (mean -0.56◦ ±0.57). Changes in B-Nperp were (-1.85mm±1.36).Overjet correction was obtained and no significant changes in the maxillary incisor angulation was observed. There was proclination of mandibular incisors by (mean 6.43◦±2.11).
Conclusions: The use of intermaxillary Class III elastics and miniplates in the orthopedic treatment of skeletal Class III is a successful technique with more skeletal than dental effects.