Cephalometric evaluation of patients with Class III malocclusion after face mask therapy in mixed dentition period

Among different treatment options for patients with Class III malocclusion, orthopedic protraction of maxilla can be a beneficial treatment procedure during the mixed dentition period. The aim of this study was to evaluate the cephalometric changes of Class III patients in the mixed dentition period following face mask therapy without any maxillary expansion. This study was conducted to compare the pre and post treatment conditions of 10 children in mixed dentition period that had class III malocclusion and maxillary deficiency according to the Steiner and Mc Namara's analyses. These patients were treated with protraction face mask without any maxillary expansion. The cephalometric changes of maxilla, mandible, soft tissue and dental relationships during treatment were recorded and analyzed using Paired sample T test. Significant changes were found in several variables [P < 0.05]. The mean improvement in overjet was 2.3 mm, the N.Sn.Pog angle decreased 3.5 degrees and the soft tissue profile was improved greatly. A Class I molar relationship was also achieved. The ISA and ItoNA distances increased 2.8 and 2.3 mm respectively, resulting from anterior movement of maxillary incisors. Face mask therapy without maxillary expansion is able to improve the horizontal position of maxilla in Class III malocclusion during the mixed dentition period