• 대한치과교정학회지
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• 제47권4호
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• pp.256-267
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• 2017

Objective: To evaluate transverse skeletal and dental changes, including those in the buccolingual dental axis, between patients with skeletal Class III malocclusion and facial asymmetry after bilateral intraoral vertical ramus osteotomy with and without presurgical orthodontic treatment. Methods: This retrospective study included 29 patients with skeletal Class III malocclusion and facial asymmetry including menton deviation > 4 mm from the midsagittal plane. To evaluate changes in transverse skeletal and dental variables (i.e., buccolingual inclination of the upper and lower canines and first molars), the data for 16 patients who underwent conventional orthognathic surgery (CS) were compared with those for 13 patients who underwent preorthodontic orthognathic surgery (POGS), using three-dimensional computed tomography at initial examination, 1 month before surgery, and at 7 days and 1 year after surgery. Results: The 1-year postsurgical examination revealed no significant changes in the postoperative transverse dental axis in the CS group. In the POGS group, the upper first molar inclined lingually on both sides (deviated side, $-1.8^{\circ}{\pm}2.8^{\circ}$, p = 0.044; nondeviated side, $-3.7^{\circ}{\pm}3.3^{\circ}$, p = 0.001) and the lower canine inclined lingually on the nondeviated side ($4.0^{\circ}{\pm}5.4^{\circ}$, p = 0.022) during postsurgical orthodontic treatment. There were no significant differences in the skeletal and dental variables between the two groups at 1 year after surgery. Conclusions: POGS may be a clinically acceptable alternative to CS as a treatment to achieve stable transverse axes of the dentition in both arches in patients with skeletal Class III malocclusion and facial asymmetry.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제41권
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• pp.23.1-23.10
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• 2019

The choice of surgical technique in orthognathic surgery is based primarily on the surgical treatment objectives (STO), which is a fundamental component of the orthognathic treatment process. In the conventional orthodontics-first approach, presurgical planning can be performed twice, during the preorthodontic (initial STO) and presurgical phases (final STO). Recently, a surgery-first orthognathic approach (SFA) without presurgical orthodontic treatment has been introduced and combined initial and final STO at the same time. In contrast to the conventional surgical-orthodontic treatment protocol that includes preoperative orthodontics for dental decompensations to maximize stable postoperative occlusion, the SFA potentially shortens the treatment period and minimizes esthetic concerns during the decompensation period because skeletal problems are corrected from the beginning. The indications for the SFA have been proposed in the literature, but no consensus exists. Moreover, because dental occlusion of the pre-orthodontic arches cannot be used as a guide for establishing the surgical treatment plan, there are fundamental limitations in accurate prediction of postsurgical results in the SFA. Recently, the concepts of postsurgical orthodontic treatment are continuously changing and evolving to overcome this inherent limitation of the SFA. The elimination of presurgical orthodontics can change the paradigm of orthognathic surgery but still requires cautious case selection and thorough discussion and collaboration between orthodontists and surgeons regarding the goals and postoperative management of the orthognathic procedure.

• 대한치과교정학회지
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• 제46권5호
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• pp.301-309
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• 2016

Objective: The aim of this study was to evaluate the skeletal and dental changes after intraoral vertical ramus osteotomy (IVRO) with and without presurgical orthodontics by using cone-beam computed tomography (CBCT). Methods: This retrospective cohort study included 24 patients (mean age, 22.1 years) with skeletal Class III malocclusion who underwent bimaxillary surgery with IVRO. The patients were divided into the preorthodontic orthognathic surgery (POGS) group (n = 12) and conventional surgery (CS) group (n = 12). CBCT images acquired preoperatively, 1 month after surgery, and 1 year after surgery were analyzed to compare the intergroup differences in postoperative three-dimensional movements of the maxillary and mandibular landmarks and the changes in lateral cephalometric variables. Results: Baseline demographics (sex and age) were similar between the two groups (6 men and 6 women in each group). During the postsurgical period, the POGS group showed more significant upward movement of the mandible (p < 0.05) than did the CS group. Neither group showed significant transverse movement of any of the skeletal landmarks. Moreover, none of the dental and skeletal variables showed significant intergroup differences 1 year after surgery. Conclusions: Compared with CS, POGS with IVRO resulted in significantly different postsurgical skeletal movement in the mandible. Although both groups showed similar skeletal and dental outcomes at 1 year after surgery, upward movement of the mandible during the postsurgical period should be considered to ensure a more reliable outcome after POGS.

• 대한치과교정학회지
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• 제33권1호
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• pp.1-9
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• 2003

본 연구에서는, 술전 교정전 예측치와 교정 후 실측치 사이에 나타나는 오차의 크기와 정확성 및 어떠한 요소가 그러한 결과에 영향을 미치는지에 대해 평가하고자 하였다. 연세대학교 치과병원 교정과에서 골격성 III급 부정교합으로 진단되어 술전 교정치료 및 양악수술을 받은 환자 가운데 조건에 부합되는 45명(남자 17명, 여자 28명)을 선별하여, 초진 상태를 T1, 교정 치료전 예측치를 T2, 술전 교정후를 T3로 정의하고 각각의 계측치를 수평과 수직좌표로 나누어 측정하였다. 또한 환자의 어떠한 진단적 요소가 술전교정의 예측치와 실측치 사이의 차이에 영향을 미치는지 알아보기 위해 연구대상을 arch length discrepancy (ALD), 상$\cdot$하악 전치의 치축(U1 to SN, IMPA), curve of Spee(COS), 발치 여부, 발치한 치아의 종류 등에 의해 여러 군으로 분류하여 유의성을 평가하였으며 다음과 같은 결과를 얻었다. 1. U6mbc, L1x의 수평 좌표와 U1i, U1x, W6me, U6mbc, L6mbc의 수직 좌표에서 예측한 위치와 수술직전의 실제 위치의 차이가 유의성(p<0.05) 있게 나타났다. 2. 예측의 정확성은 수평적인 차이의 예측에 있어서 수직적인 차이의 예측에 비해 상대적으로 높게 나타났다. 3. 하악에서보다 상악의 많은 계측점에서 예측치와 실측치 사이의 유의한 차이(p<0.05)가 관찰되었다. 4. 상악의 경우 발치 여부 및 발치한 치아의 종류, ALD의 양에 따라 상악 전치와 제1대구치 위치의 예측에 유의한 차이(p<0.05)를 보였으며, 하악의 경우에는 ALD의 양과 IMPA에 따라 하악 전치와 제1대구치의 위치의 예측에 유의한 차이(p<0.05)를 나타냈다. 이번 연구에서 얻은 결과를 통하여 술전 교정전 예측치와 실측치 사이의 오차의 정도와 그것에 영향을 미치는 요소들을 분석하고 회귀 계수를 구함으로써, 악교정 수술을 동반한 교정 환자의 치료 계획 시 예측의 정확성을 높일 수 있을 것으로 생각된다. 또한 수직적인 예측에 있어서는 앞으로 더 많은 연구가 이루어져야 할 것으로 생각된다.