A comparative study of initial lateral cephalometric characteristics: mandibular setback surgery only versus mandibular setback surgery with advancement genioplasty / 대한치과교정학회지

OBJECTIVE: The aim of this study was to compare the initial lateral cephalometric characteristics in two groups of patients: those that had mandibular setback surgery only and those that had mandibular setback surgery with advancement genioplasty. METHODS: The lateral cephalograms of thirty-one patients were studied. Twenty-one Class III patients (group A) had only madibular setback surgery. Twelve Class III patients (group B) had mandibular setback surgery with advancement genioplasty. RESULTS: Differences between two groups were found in N-Me, ANS-Me, Occlusal Plane angle, Palatal Plane to U1, Mandibular Plane to L1, Mandibular Plane to L6, SN to U1, Sn-Stms, and Pog' projection. Compared to group A, group B showed more linguoversion and extrusion of upper incisors, more extrusion of lower incisors and lower first molar, and more steepness of the occlusal plane. N-Me, ANS-Me, and Sn-Stms were also longer in group B. But Pog' projection was shorter than group A. CONCLUSION: We conclude that certain initial lateral cephalometric characteristics may help indicate the inclusion of advancement genioplasty when mandibular setback surgery is planned in skeletal Class III patients.

Soft tissue changes associated with advancement genioplasty in skeletal class III individuals receiving mandibular set-back surgery / 대한치과교정학회지

PURPOSE: The purpose of this study was to assess the hard and soft tissue changes associated with mandibular bilateral sagittal split osteotomy and genioplasty. METHODS: This is a retrospective study of 40 patients who underwent either bilateral sagittal split osteotomy for mandibular setback (BSSO group, n = 20) or in combination with advancement genioplasty (Genio group, n = 20). Lateral radiographs, were taken before and immediately after surgery, and at least 6 months after surgery. RESULTS: Comparing hard and soft tissue changes between the BSSO group and Genio group, there were significant differences in the lower incisor, soft tissue B point (B'), and soft tissue Pogonion (Pg') (p < 0.5). The mean ratio of hard and soft tissue changes for B/B', Pg/Pg', and Menton/soft tissue Menton after surgery in the BSSO group was 0.997, 0.965, and 1.022 respectively, and 0.824, 0.602, and 0.887 respectively in the genio group. Significant differences were found between the two groups. There were significant differences in lip thickness (B-B', Pg-Pg') in the Genioplasty group between pre and postsurgery, but not in the BSSO group. Pogonion to Labrale inferior and B' had a correlation coefficient of 0.833, 0.922, respectively for the BSSO group, and 0.775, 0.799 for the Genio group. CONCLUSIONS: The results indicate that there is a significant difference between bilateral sagittal split osteotomy with or without genioplasty in the lower facial esthetics values. The combination of mandibular setback and genioplasty had a smaller change in soft tissue thickness of the symphysis area after surgery than that of mandibular setback only.

The Changes of Bone and Soft Tissue after Maxillary Anterior Segmental Osteotomy and Advancement Genioplasty

PURPOSE: Mid and lower facial convexity is more common in Oriental people than in Caucasian. Bimaxillary dentoalveolar protrusion is characterized by procumbent teeth, protruding lips, acute nasolabial angle, gummy smile, receding chin, facial convexity. Especially, pure maxillary dentoalveolar protrusion is less frequent than bimaxillary dentoalveolar protrusion. Therefore, it is important to make an accurate decision for the operation throughout the history taking, cephalogram, dental cast to arrive at accurate diagnosis and surgical plan. METHODS: From December 2002 to June 2004, ten patients with maxillary dentoalveolar protrusion and microgenia were corrected by maxillary anterior segmental osteotomy and advancement genioplasty. 10 patients were analyzed by preoperative and postoperative clinical photography, posteroanterior and lateral cephalograms. RESULTS: No major complications were occurred throughout the follow-up period except one of the over- recessed, otherwise most of the patients were satisfied with the result. CONCLUSION: We could correct the occulusal relationship with teeth and improve lower facial profile, asthetically and functionally, by maxillary anterior segmental osteotomy and advancement genioplasty.