Comparison of Changes in Intraoral Dynamic Space (Donders Space) with Myofunctional Therapy in Skeletal Class II Division 1 Malocclusion: An In Vivo Study.

AIM: To evaluate the changes in the intraoral dynamic space with myofunctional therapy in skeletal class II division 1 malocclusion using three-dimensional digital volume tomography (3D-DVT). MATERIALS AND METHODS: The study type is observational and the duration of intervention was 3 years. Dental casts obtained from 20 samples of 11-14 years age-group were collected and 3D-DVT scans were performed prior to and after the myofunctional therapy. The parameters depicting the arch perimeter, arch width, arch length, arch shape, and arch volume on dental cast were used in the study using several linear and volumetric measurements. All parameters were compared before and after myofunctional therapy using t-test. RESULTS: The Intraoral volume before myofunctional therapy (T0) was 5.59 mL and after myofunctional therapy (T1), it was 7.22 mL. Significant changes were seen in intraoral volume, arch perimeter, arch length, and intercanine and intermolar arch width and the arch shape. Linear and volumetric measurements were increased after myofunctional therapy. CONCLUSION: Myofunctional appliances lead to an expansion in the anteroposterior and sagittal direction thus increasing the Donders space and leading to proper formation of dental arches and proper positioning of the teeth. CLINICAL SIGNIFICANCE: Myofunctional therapy is an effective method of increasing arch width, length, and volume. This therapy can be used in routine practices in young children with constricted arch and improvement in facial esthetic.