Effects of Orthodontic Functional Appliances in Relation to Skeletal Maturation of Cervical Vertebrae in Class II Malocclusion

Abstract

Aim: To evaluate the effects produced by functional orthodontic appliances at dental and skeletal level in relation to the level of skeletal maturation in class II patients. Study design: Longitudinal and observational study. Patients selected for the study had been wearing Sander Bite Jumping Appliance (SBJA) for at least 12 months; they were first diagnosed (T1) with skeletal class II according to Ricketts’ cephalometric analysis, and had had lateral cephalograms taken before and after orthopaedic treatment (T2). Variables studied at T1 and T2 were: facial convexity, inclination of the upper and lower incisors, and facial depth. Results were compared between T1 and T2 for each variable and in relation to cervical maturation stage (CVS) according to the Lamparski analysis. Statistical analysis was performed using Shapiro–Wilk, t-student, Analysis of Variance (ANOVA) and multiple comparison tests, taking as statistically significant a p-value <0.05. Results: A final sample of 235 patients was obtained. Statistically significant differences were found in the inclination of the mandibular incisors between T1 and T2 and among the different cervical stages when the functional appliances were placed in CVS1 (p = 0.000), CVS2 (p = 0.04) or CVS5 (p = 0.048). For the remaining variables, significant differences were also found between T1 and T2, but these differences were similar in all cervical stages. Conclusions: A significant proclination of the mandibular incisors was found when the functional appliance was placed during CVS1, CVS2, or CVS5. Time of placement of the functional appliances was not statistically significant for the remaining variables studied.