Sequence of treatment in mandibular prognathism patients.

Intraoral vertical ramus osteotomy (IVRO) and advancement genioplasty are effective and predictable methods of treating selective individuals with mandibular prognathism. The sequence of performing these procedures does have a clinical effect, but this is not found in the literature. The purpose of this article is to introduce the clinical implication of the sequence of procedures and to recommend the preferred sequence based on experience. A retrospective study was conducted on 75 patients treated by IVRO with or without genioplasty. In 31 patients, IVRO was performed without genioplasty; only one patient suffered from transient hypoesthesia. When IVRO was performed before genioplasty (sequence I) in 20 patients, nine suffered from mental nerve hypoesthesia. However, when IVRO was performed after genioplasty (sequence II) in 24 patients, permanent mental nerve anesthesia occurred in five patients and mental nerve hypoesthesia in 15 patients. Based on these results, it is recommended that IVRO be performed before genioplasty.