Introduction
malocclusion, condylar head, glenoid fossa, dentoskeletal, Class II malocclusions
TMJ
One of the controversial topics in orthodontics is the best time to treat Class II malocclusions with mandibular retrognathism. During the pre-pubertal phase, with high growth potential, functional appliance treatment can alter the jaw relationship resulting in dentoalveolar and/or orthopedic changesIt has been reported that the treatment of post-adolescent and young adults Class II cases with Herbst appliance could exploit the residual mandibular growth and induce remodeling processes in the region of the temporomandibular joint even after the age of 20 years and could consequently be a proper alternative to orthognathic surgery, particularly in mild skeletal Class II casesThe skeletal and dental effects of Herbst appliance in the pre-and post-pubertal periods had been investigated extensively by conventional cephalometric radiographs. However, identifying some landmarks such as condylar head, glenoid fossa, and TMJ spaces cannot be accurately detected using traditional cephalometric tracing/digitization techniquesThe objective of this study was to compare the skeletal and dental effects of using cast splint supported Herbst IV appliance for the treatment of skeletal Class II malocclusion in the Pre-pubertal and Post-pubertal periods using CBCT. The null hypothesis was that the dentoskeletal changes in Class II malocclusion treatment using Herbst appliance in the Pre-pubertal is more than the Post-pubertal stage due to the remaining growth potential for the pre-pubertal patients, the alternate hypothesis was that there is no difference in the dentoskeletal changes in Class II malocclusion treatment using Herbst appliance in the Pre-pubertal and Post-pubertal growth stages.