The effects of face mask therapy with and without rapid maxillary expansion in adolescent patients.

OBJECTIVE

To examine the effects of face mask therapy with and without associated rapid maxillary expansion (RME) in adolescent patients presenting with skeletal Class III malocclusion characterised by maxillary retrognathism.

METHODS

Case records consisting of lateral cephalograms and hand-wrist films of 43 patients with hypoplastic maxillary Class III malocclusions treated using a face mask with and without an RME were analysed. The patients were divided into two groups; Group A (N = 27) were treated with a face mask coupled with rapid maxillary expansion and patients in Group B (N = 16) were treated with a face mask appliance only. Ten cephalometric linear and 9 angular variables were measured to assess the dentofacial changes. Within group and between groups comparisons were determined by a paired t-test and Student's t-test, respectively.

RESULTS

Forward displacement of the maxilla and a clockwise rotation of the mandible occurred in both groups. The maxillary-mandibular relationship improved and soft-tissue changes resulted in a more convex profile. The maxillary incisors moved forward only in Group B subjects but the mandibular incisors moved backward in both groups.

CONCLUSIONS

Face mask therapy with and without an associated RME improved skeletal Class III malocclusion by a combination of skeletal and dental changes. These results suggested that the use of an RME should be based on clinical criteria rather than assisting the Class III correction.