Surgical Mandibular Advancement Research Articles

Nature of relapse after surgical mandibular advancement.

Pre-operative, post-operative and follow-up cephalometric records of 16 cases of mandibular retrognathia treated by surgical mandibular advancement were analysed retrospectively. The results showed good mean stability in the mandibular advancement with variable individual relapse. The pre-operative mandibular plane angle, magnitude of the advancement and post-operative increase in the posterior lower face height were the variables chiefly related to relapse. There appeared to be limited control over the posterior segment which was liable to distraction and rotation. The follow-up changes were time linked. Both mechanical and biological factors are postulated to explain the relapse.

Changes of the hyoid bone and tongue following advancement of the mandible

Little is known concerning the adaptation of the tongue and hyoid bone after surgical mandibular advancement. This study was undertaken to evaluate the relationship between tongue and hyoid bone posture and their adaptation following mandibular advancement in fourteen adults. The data indicate that (1) there is no statistically significant correlation between changes in the posture of the tongue and hyoid bone; (2) the hyoid bone returns toward its presurgical posture; and (3) the tongue assumes a new position relative to both the cranial base and the mandible. The changes in tongue position occurred immediately after surgery and persisted 2 years postoperatively.

Surgical mandibular advancement: A cephalometric analysis of treatment response

Fifty-two cases of surgical advancement of the mandible were evaluated by retrospective cephalometric and computer analysis for longitudinal skeletal and dental changes an average of 3 1 2 years after surgery. Postsurgical treatment response appeared to be a multifactorial biologic phenomenon with considerable individual variability. Results showed generally good stability after mandibular advancement, with a minimal to moderate tendency toward skeletal relapse during intermaxillary fixation. Positional change of the proximal segment was the most important parameter in determining stability or relapse of the advanced mandible. Anteroinferior displacement of the condyle and increased posterior facial height were found to be important factors in the skeletal relapse observed during the period of intermaxillary fixation. The magnitude of mandibular advancement was a reliable surgical predictor of postsurgical relapse. Preoperative mandibular plane angle, postfixation intersegment instability, and patient's age cannot be isolated as being solely responsible for specific postsurgical changes.

Surgical mandibular advancement studied with computer-aided cephalometrics

Surgical mandibular advancement studied with computer-aided cephalometrics

Treatment of severe mandibular retrusion in Class II, Division 2 malocclusion

The case of an adult patient with a severe mandibular retrusion of the Class II, Division 2 malocclusion type has been presented. The patient's marked anteroposterior discrepancy was complicated by the severe malocclusion. The solution to this case involved presurgical orthodontic treatment to allow for surgical mandibular advancement by a modified sagittal osteotomy and postsurgical orthodontic care for alignment of the dentition. A discussion of the importance of the patient's facial growth type for stable mandibular advancement has also been presented.