Hard and Soft Tissue Stability of Orthognathic Surgery

Abstract

Objective: To test the hypothesis that there is no difference in the stability of the hard and soft tissue changes following a surgical mandibular setback using a sagittal split ramus osteotomy or an intraoral vertical ramus osteotomy. Materials and Methods: The samples consisted of 45 female patients with mandibular prognathism, who were divided into two groups. Twenty-three underwent a sagittal split ramus osteotomy (SSRO) with rigid fixation by titanium mini-screws and maxillomandibular fixation (MMF) for 14.0 Ϯ 0.7 days. Twenty-two underwent intraoral vertical ramus osteotomy (IVRO) without rigid fixation, and MMF was released 21.5 Ϯ 3.3 days after surgery. Data were collected from standardized cephalometric radiographs taken at the start of preoperative orthodontic treatment (T1), immediately after surgery (MMF, T2), and the completion of postoperative treatment (T3). Angular measurements were compared on each of T1, T2, and T3. Results: There were no significant differences in the pretreatment hard and soft tissue morphology between the SSRO and IVRO. However, when fixation was released, the mandible was posteriorly positioned in the IVRO group. In the soft tissue profile, the mental region was located backward in the IVRO group at postoperative stage (T3). Conclusions:The hypothesis is rejected. The soft tissue profile of the IVRO group especially showed a retromandibular position after postoperative treatment in comparison with the SSRO group. This tendency of the IVRO group would contribute to the database for treatment planning and prediction. (Angle Orthod. 2009;79:158-165.)

Assessment of skeletal stability of intraoral vertical ramus osteotomy with one-day maxillary–mandibular fixation followed by early jaw exercise

“…While postoperative MMF is generally required for a period of couple of days to two weeks for SSRO (Yoshioka et al, 2008, Kitahara et al, 2009, IVRO requires two to six weeks, depending on the institution where it is performed (Ueki et al, 2005, Chen et al, 2011. There is no consensus thus far on what constitutes an adequate period of MMF after IVRO.…”

Three-dimensional analysis of hard and soft tissue changes in patients with facial asymmetry undergoing 2-jaw surgery

“…In general, the treatment plan for orthognathic surgery depends on the amount of bone that has to be moved, although the assessment of facial aesthetic changes to be accomplished by surgery mostly depends on the soft tissue changes. 2 It is therefore important to be able to predict precisely the postoperative correlation of hard and soft tissue changes when creating a treatment plan.…”

Cephalometric evaluation of surgical mandibular advancement

“…Combined orthodontic and surgical treatment is the best choice for adult individuals, since it results in better esthetic appearance and function, followed by long term stability. 1,2,3,4 Compensatory treatment can lead to occlusal and muscular changes, dysfunctional problems, and TMJ disorders. 5 The diagnosis and treatment plan for patients with dentoskeletal deformities should be carried out individually, with cephalometric, occlusal and facial analyses, which take into account the position of the maxillary and mandibular incisors on the basal bone.…”