The Versatility of Extraoral Vertical Ramus Osteotomy for Mandibular Prognathism: A Prospective Study

Introduction: Orthognathic surgery simply means alignment of the jaws. The aim of orthognathic surgery is to normalize the relationship of the jaws between themselves and the rest of the craniofacial complex. Mandibular prognathism is a common clinical problem all over the world. Currently, sagittal ramus osteotomy is the primary choice for correcting most cases of mandibular retrognathism and prognathism. The surgical option for extreme cases of mandibular prognathism is extraoral vertical ramus osteotomy (EVRO) or intraoral vertical ramus osteotomy (IVRO) or inverted L osteotomy. Aim: The aim of this study was to evaluate the versatility of EVRO for mandibular prognathism. Materials and methods: Ten patients with the chief complaint of mandibular prognathism with no history of keloid tendency were included in the study. EVRO was done for all patients. The parameters based on which the outcome of the surgical procedure was assessed were time taken for the surgical procedure, facial harmony both in frontal and profile views postoperatively, and intraoperative and postoperative complications, and assessment of the postoperative results was done through orthopantomogram (OPG) and 3D CT scan. Results: The time taken for the entire surgical procedure, starting from incision to closure, varied between 80 and 94 minutes with the average time taken for the surgery being 90 ± 8.80 minutes. It was found that there was a statistically significant difference between preoperative (M = 53.4, SD = 5.854) and postoperative evaluation (M = 47.5, SD = 5.039) of the posterior nasal spine to nasion 1 (PNS-N 1) horizontal plane (HP) (mm) with p < 0.001. Similarly, there was a statistically significant difference between preoperative (M = 81.4, SD = 2.716) and postoperative evaluation (M = 74.4, SD = 3.627) of mandible body length (mm) with p < 0.001. However, no statistically significant difference exists between the preoperative and postoperative evaluation of anterior nasal spine (ANS) to PNS (mm) and ramus height Ar-Go (mm). Conclusion: EVRO is an acceptable surgical procedure owing to the fact that it is relatively simple to carry out, its lack of complications, and its good results.