The effects of facemask and reverse chin cup on maxillary deficient patients.

Introduction: The aim of this randomized clinical trial was to assess differences in the effects of face mask and reverse chin cup therapy on maxillary deficient growing patients.

Methods: The sample consisted of 42 class III patients with maxillary deficiency randomly divided into two equal groups. Twenty-one patients (10 males and 11 females) with a mean age of 8.9 (SD: 1.4) years were treated with a face mask for 18 (SD: 2) months. Twenty-one patients (9 males and 12 females) with the mean age of 9.2 (SD: 1.1) years were treated with a reverse chin cup for 19 (SD: 4) months. Cephalometric radiographs were taken at the beginning and end of treatment and the cephalometric measurements were analysed. Paired t-tests and a Wilcoxon test were used for intra-group evaluations. Mann-Whitney test was used for inter-group evaluations.

Results: Sella-Nasion-A point (SNA) was increased by 1° (SD: 1.7°) (P<0.003) and 1.8° (SD: 1.7°) (P<0.001) in the face mask and reverse chin cup groups, respectively. The IMPA decreased by 4.1° (SD: 6.5°) in face mask group (P<0.009) and 3.1° (SD: 4.7°) in the reverse chin cup group (P<0.008). However, no statistically significant differences were seen in changes between the two groups.

Conclusion: Both face mask and reverse chin cup appliances are successful at moving the maxilla forward.