Soft tissue facial profile in Class III malocclusion: long-term post-pubertal effects produced by the Face Mask Protocol

OBJECTIVES: The objective of this study was to analyze soft tissue changes produced by rapid maxillary expansion and facial mask therapy in growing Class III patients. MATERIALS: The treated group consisted of 32 Caucasian patients (15 females and 17 males) with dentoskeletal Class III malocclusion treated with the Face Mask Protocol (FMP, rapid maxillary expander, facial mask, and removable lower bite-block). All patients were evaluated before treatment (T1; mean age, 8.4 years), at the end of active treatment (T2; mean age, 10.7 years), and at a post-pubertal follow-up observation (T3; mean age, 15.8 years). The treated group was compared with a matched control group of 20 untreated subjects (10 females and 10 males) with dentoskeletal Class III malocclusion. Statistical comparisons between two groups were performed with the independent samples t-test (P < 0.05). RESULTS: Significant improvements were found during the long-term T1-T3 interval for profile facial angle (-5.8°), nasolabial angle (-4.4°), mandibular sulcus (-10.3°), upper lip protrusion (+0.7 mm), and lower lip protrusion (-1.1 mm) in the treated group. No significant post-pubertal effects were found in terms of lower face percentage between two groups. LIMITATIONS: This study has a retrospective design and it used a historical control sample. CONCLUSION: The FMP induced positive effects on soft tissue facial profile with a good long-term post-pubertal stability.