Abstract
A 20-year-and-6-month-old female patient had undergone mandibular lengthening by distraction osteogenesis for an Angle Class II division 2 case with micrognathia. We experimented with facial, skeletal, and airway changes using cephalometry, and she was also analyzed for the possible changes of oral functions between before and after treatments.
The results were as follows:
1) The mandibular lengthening was effective within ten days, and the patient's profile and jaw relationship were improved, respectively, after the treatment.
2) A relapse was not seen and the post-treatment conditions were stable after removing the lengthening device.
3) As for the airway analysis, the nasopharyngeal airway was expanded following the mandibular lengthening.
4) As for oral functions, mouth opening increased and electromyogram activity increased after the mandibular lengthening. Harmony between the temporal and masseter muscles was obtained.
From these results, it was suggested that mandibular lengthening by distraction was a favorable technique to advance the mandible of a Angle Class II case with micrognathia.
