Denture-frame modifications in class III patients treated with rapid palatal expansion and facemask: a prospective controlled study

Abstract

Aim: The aim of this prospective controlled investigation was to analyze the short-term cephalometric treatment outcomes, according to the denture frame analysis proposed by Sato, of rapid palatal expansion (RPE) and facial mask (FM) therapy.

Methods: A group of 21 patients with Class III malocclusion treated with the RPE and FM (TG) was compared with untreated Class III controls (CG). The mean age of treatment group was 8.8 years; treatment consisted of 4 weeks of RPE activation (0.20 mm/die) followed by 14 hours wear of the FM for a mean of 333.1 days. As CG were used the data published by Tanaka and Sato. Pre- and post-treatment cephalometric values were compared and statistical analyzed with one-sample t-test. A P-value <0.05 was considered statistically significant.

Results: For almost all parameters the differences pre and post treatment values resulted significantly different compared to those observed in CG. Regarding conventional occlusal plane (POC) values some differences compared to control group were found but they were not statistically significant (P=0.067) while for aterior occlusal plane (POA) no differences where noticed.

Conclusion: This study revealed an increase in inter-jaw angle during treatment with FM and RPE, an increase in the inclination of the posterior occlusal plane with respect to the Frankfurt plane and a posterior and lower adaptation of the mandible.