Change in cervical posture after maxillary protraction with facemask therapy: A retrospective study.

Introduction: The aim of this study was to investigate the effects of rapid maxillary expansion (RME) and facemask therapy on cervical vertebral column in growing patients with skeletal class III malocclusion.

Material and methods: The pre- (T1) and post-treatment (T2) cephalometric records of eighteen subjects (10 girls, 8 boys; mean age, 9.47 ± 1.08 years) treated with RME and facemask therapy were included in this study. Angular measurements of three sagittal, one vertical, and eleven cervical parameters were assessed. The Shapiro-Wilk test was used to validate the normality of data and equality of the variances was checked using the Levene's test. The difference between the mean values of T1 and T2 was verified using a paired t-test.

Results: A significant difference existed between pre- and post-treatment SNA (P < 0.05), SNB (P < 0.05), and ANB (P < 0.05) angles, showing a change in maxillomandibular sagittal relationship. Two upper cervical vertebral parameters, SN-OPT (odontoid process tangent) (P < 0.05) and MP-OPT (P < 0.05), also revealed a significant difference.

Conclusions: The facemask and RME improves maxillomandibular sagittal skeletal relationship (SNA, SNB, and ANB) in growing class III patients. There was greater forward inclination of craniocervical posture after RME and facemask therapy, and upper cervical vertebral column (SN-OPT) shows highly significant improvement as compared with other cervical parameters.