Investigation of the changes in maxilla, mandible and airway in class iii cases usi̇ng rapi̇d maxillary expansion and petit type face mask

Aim: The aim of this study was to evaluate the changes (maxillary, mandibular, airway dimension) after rapid maxillary expansion and face mask therapy by compairing control groups. Material and Method: This retrospective study was conducted on cephalometric films of 47 growing subjects (25 females, 22 males) with skeletal Class III cases. The average chronological age of treatment and control group was 10.52 and 10.57 years respectively. Bonded type rapid maxillary expansion appliance and Petit type face mask were applied to the treatment group consisting of 26 cases (14 girls, 12 boys). The force applied to the bonded type rapid maxillary expansion appliance with a face mask is designed to make 200 angles with the occlusal plane. A 500 gr of force per side was applied for at least 18-20 hours a day. The treatment took an average of 8 months until a positive overjet was obtained. Cephalometric films were taken before after treatment. The control group consists of 21 cases (11 girls, 10 boys). Observation period of the control group was 7 months. During this period, no orthodontic treatment was applied to the controls. The paired t test was used to evaluate intragroup differences, and the independent t test was used to evaluate intergroup differences. Results: When we compaired differences between treatment and control groups; the change in the SNA (p<0.01), SNB (p<0.001), ANB (p<0.001), N-S-Gn (p<0.05), S-N-Pg (p<0.05), U1/SN (p<0.05), IMPA (p<0.05) angles, Witts appraisal (p<0.001), CoB-CoA (p<0.05), ANS-Me (p<0.05), Overjet (p<0.001), Overbite (p<0.05), Ls-E Line (p<0.01), Nasopharynx (p<0.01) and Upper oropharynx (p<0.05) areas were found statistically significant. Conclusion: It has been observed that maxillary growth was stimulated, maxillo-mandibular relationship was improved and upper airway area was increased with the use of rapid maxillary expansion and face mask. Key Words: rapid maxillary expansion, maxillary retrognathia, class III, face mask