• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제33권2호
• /
• pp.190-197
• /
• 2011

The management of mandibular prognathism was revolutionized by the advent of the of sagittal split ramus osteotomy (SSRO) technique as described by Obwegesser and Trauner in 1957. Facial nerve palsy following SSRO is a rare but serious problem. In the event of post-operative facial palsy, careful clinical and neurophysiological investigations such as a nerve condunction test for facial function is mandatory. The authors examined patients with facial palsy following SSRO. Patients recovered after 3~4 months and we had performed clinical examinations with electromyography and nerve conduction tests during follow-up period.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제30권2호
• /
• pp.131-135
• /
• 2004

The purpose of this study was to evaluate the resistant force of medial pterygoid muscles against the mandibular advancement and distraction to anterior, and inquire into the relationship between medial pterygoid muscles and cephalometric variables. Sixty six patients with class III malocclusion underwent bilateral sagittal splitting of ramus with intraoralvertico-sagittal ramus osteotomy for mandibular set-back. The spring scale was used to measure the resistance of medial pterygoid muscles after splitting of ramus. Skeletaldental cephalometric analysis was made and statistic package was used for correlation between resistance and cephalometric variables. The resistant force of the right medial pterygoid muscle was greater than the left one in Koreans with class III malocclusion, and the force had a linear regression relationship with facial depth. The results suggested that facial depth has significant correlation with the resistance of medial pterygoid muscle, which can be acquired from patient's cephalometric analysis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제28권1호
• /
• pp.1-6
• /
• 2002

When bilateral sagittal split ramus osteotomy or mandibular angle reduction are carried out, we have to consider the position of inferior alveolar nerve. For bone splitting or resection using a saw or an osteotome, the bucco-lingual position of the inferior alveolar nerve plays an important role in the preventing perioperative complications such as paresthesia or anesthesia. Because it is rare to find literatures concerning the mean anatomic position of the inferior alveolar nerve in Koreans, we investigated 30 patients who underwent to take CT and orthopantomogram for implant surgery, and evaluated the bucco-lingual position and vertical relationship of the inferior alveolar nerve at the mandible. The results showed that the distance between inferior alveolar nerve and buccal plate was the farthest at mandibular second molar ($7.1{\sim}7.4mm$) and the nearest at mandibular angle area ($4.4{\sim}4.8mm$). But it was no statistical relationship between the bucco-lingual postion of inferior alveolar nerve on the CT and its vertical position on the OPT. In conclusion, the results suggest that a careful surgical procedure is needed at the mandibular angle area to avoid a nerve damage and there are sufficient bone materials at the mandibular second molar are for bilateral sagittal split ramus osteotomy or mandibular angle reduction or plate fixation. And OPT is not usefull for the evaluation of a relative bucco-lingual position of inferior alveolar nerve in relation to its vertical postion on the OPT.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제23권4호
• /
• pp.348-356
• /
• 2001

The factors related to relapse in 20 skeletal class III patients who performed two-jaw surgery with Le Fort I maxillary osteotomy and bilateral sagittal split ramus osteotomy was investigated. All patients were fixed with miniplate on the maxilla and three screws at each mandible. Cephalograms taken at preoperative, immediate postoperative and 8 months postoperative after surgery were traced and digitized. 1.The horizontal and vertical relapse of maxilla and mandibular chin points was within 1mm postoperatively. Compare to the preceding report concerning the mandibular set-back surgery only group, this reveals two-jaw surgery for mandibular prognathism using rigid fixation is more stable. 2.Although there was no significant relapse tendancy was observed at chin points, the screw tip land-marks moves anterio-superiorly and each side of the screws moved as a one unit. The screw tip points moved similar direction to the masticatory force and this movements might be influenced by the muscular tension to the distal segment of the mandible. 3.According to the regression analysis, the amount of horizontal and vertical movement of mandibular set-back influenced the mandibular relapse. However, direction and amount of maxillary surgical movement did not inf1uenced the maxillary and mandibular relapse.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제32권2호
• /
• pp.132-140
• /
• 2010

Purpose: The aim of this study is to identify the usefulness of unilateral mandibular angle ostectomy, so-called "Lateral Angle Reduction", in asymmetric prognathism patients by the assessment of postoperative stability and esthetic results Patients and methods: For the retrospective study, 10 skeletal class III mandibular asymmetry patients who were performed SSRO and unilateral mandibular angle ostectomy, Lateral Angle Reduction, was selected. Lateral and posterioanterior cephalogram was taken before surgery (T0), 1day after surgery (T1) and 6month after surgery (T2). To know the esthetic results the facial width and lateral facial contour were examined on posterioanterior cephalogram and to know the postoperative stability B point and Incisor inferius was examined on lateral cephalogram. Statistical analysis was performed. Results: From T0 to T1, Intergonial width was significantly decreased, dominantly at shortened side but no significant changes at lengthened side. Those were well-maintained during 6 months. Lateral facial angle and Ramus angle was significantly decreased on only shortened side from T0 to T1. As a result, after surgery, there were no significant differences in all measurements between shortened side and lengthened side. Ramus deviation angle in shortened side and ramus angle in lengthened side which reflect the angulation of ramus on frontal plane didn't show significant changes after surgery and during postsurgical periods. Lower dental midline showed no statistical changes during postsurgical period. The relapse rate on B-point was 11.92%. Conclusion: Unilateral "Lateral angle reduction" in the asymmetric mandible is valuable to obtain the narrow lower face and symmetric facial contour with a good stability.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제40권
• /
• pp.36.1-36.5
• /
• 2018

Background: Botulinum toxin-A (BTX-A) injection into muscle reduces muscular power and may prevent post-operative complication after orthognathic surgery. The purpose of this study was (1) to evaluate BTX-A injection into the masseter muscle on the prevention of plate fracture and (2) to compare post-operative relapse between the BTX-A injection group and the no injection group. Methods: Sixteen patients were included in this study. Eight patients received BTX-A injection bilaterally, and eight patients served as control. All patients received bilateral sagittal split ramus osteotomy for the mandibular setback and additional surgery, such as LeFort I osteotomy or genioplasty. Post-operative plate fracture was recorded. SNB angle, mandibular plane angle, and gonial angle were used for post-operative relapse. Results: Total number of fractured plates in patients was 2 out of 16 plates in the BTX-A injection group and that was 8 out of 16 plates in the no treatment group (P = 0.031). However, there were no significant differences in post-operative changes in SNB angle, mandibular plane angle, and gonial angle between groups (P > 0.05). Conclusions: BTX-A injection into the masseter muscle could reduce the incidence of plate fracture.

• Journal of Yeungnam Medical Science
• /
• 제6권2호
• /
• pp.183-194
• /
• 1989

저자들은 2명의 하악 전돌증 환자에게 수술전 치열교정후 구내 하악지 경사 분열 골절단술을 시행하고 술후 치열교정을 계속 시행중이며 이 술식으로 다음과 같은 결과를 얻었다. 1. 전돌된 하악골의 후방이동으로 환자의 안모 추형과 심리적 열등감을 해소했으며 교합관계는 Angle 1급으로 회복하였으며 전반적인 부정교합을 치열교정과 더불어 해소했다. 2. 술후 감염과 골편 파절, 안면 지각이상, 측두하악 장애는 나타나지 않았으며 48시간 지난후 안면부 종창은 서서히 해소되었다. 3. 수술후 약간 고정은 8주간 시행했으며 악간 고정 제거 1주후 정상적인 개구가 가능했다. 4. 경조직의 후방이동에 따른 연조직의 하순과 하악 이부에서의 이동량은 본 증례에서는 거의 1:1로 나타났다. 5. 악간 고정 기관과 술후 치열고정 기간중의 회귀현상은 약간 관찰되었으나 이에 대하여는 더 오랜 기간의 연구 관찰이 필요하고 관찰중이다.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제34권2호
• /
• pp.100-105
• /
• 2012

Purpose: In general, the surgical treatment for mandibular retrognathism is represented by two methods, distraction osteogenesis (DO) and mandibular osteotomy surgery. The DO is mostly preferred when the degree of advancement of mandible is large. However, the postoperative stability of mandibular advancement using DO have not been actively investigated. Therefore, in the present study we have compared the postoperative stability between DO and bilateral sagittal split ramus osteotomy (BSSRO) in mandibular retrognathism. Methods: Seven patients who had been treated by DO and thirteen patients with BSSRO were included in this study. Serial lateral cephalograms were analyzed by manual tracing and the amount of the mandibular elongation was measured. To evaluate the postoperative stability, positional changes of the condylar position and B point were analyzed. Results: Mean amount of mandibular advancement was $6.51{\pm}3.57mm$ for BSSRO group and $12.43{\pm}4.35mm$ for DO group, respectively. There was no significant difference in age between the two groups (P>0.05). Mean follow up periods were 10.77 months for BSSRO group and 11.28 months for DO group, respectively. After mandibular advancement, mean positional changes in the condyle were $0.56{\pm}1.43mm$ horizontally and $0.72{\pm}1.61mm$ vertically for BSSRO group and $0.53{\pm}1.56mm$ horizontally and $0.56{\pm}1.75mm$ vertically for DO group, respectively. Mean change of distance from B point to Y-axis was $-1.76{\pm}0.83mm$ for BSSRO group and $-2.14{\pm}1.82mm$ for DO group, respectively. According to the condylar position and B point, there were no significant differences in postoperative stability between the two groups (P>0.05). Conclusion: There was no significant difference in postoperative stability between DO and BSSRO group according to condylar position and B point. Based on the results of the present study, it is hypothesized that DO would be a good treatment choice for severe mandibular retrognathism because DO could achieve more mandibular advancement and concurrent soft tissue elongation.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제18권1호
• /
• pp.120-124
• /
• 1996

The postoperative maxillary cyst develops as a delayed complication after surgical intervention or Caldwell-Luc operation in the maxillary sinus and was also reported that it could occur after Le Fort I osteotomy. This is also called as surgical cliated cyst because of its lining epithelium is usually lined by a pseudo-stratfied ciliated columnar epithelium. This report represents a case of postoperative maxillary cyst which developed within the anterior of maxilla and in association with nasal mucosa 6 years after a Le Fort I osteotomy. In 1989, 26-year-old male complained of his mandibular prognathism and underwent orthogmathic surgery, Le Fort I osteotomy, bilateral sagittal split ramus osteotomy, partial glossectomy.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제22권2호
• /
• pp.184-190
• /
• 2000

Objective : To compare two different methods of rigid fixation in postoperative stability after mandibular setback. Material and Methods : 28 patients with Class III malocclusion were treated by bilateral sagittal split ramus osteotomy(BSSRO) and mandibular setback were selected for this study. Group A(n=14) had the bone segments fixed with monocortical miniplate on the lateral side of the mandibular body and Group B(n=14) had three noncompressive bicortical screw inserted at the genial area through a transcutaneous approach. Cephalograms were taken preoperatively, postoperatively within 1 weeks and at a follow-up period (mean 8.9 months after surgery) and the amount of setback and postoperative change were measured. Results : Postoperative relapse between two groups was minimal in setback of the mandible. Statistical analysis showed no significant difference in postoperative relapse. Conclusion : This study suggests that both methods of skeletal fixation investigated give comparable postoperative stability and their use in mandibular setback appears to be a fairly stable clinical procedure .