• Maxillofacial Plastic and Reconstructive Surgery
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• 제28권1호
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• pp.49-57
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• 2006

Mandibular fractures have higher incidence rate compared to facial bone fractures because of relatively prominent form. Specially, mandibular angle fractures were known as common fracture site because of morphological anatomic structure. The mandibular third molar appears to be the most frequent impacted tooth. The mandibular third molar have influence on mandibular angle fractures according to it's eruption state. Also, the mandibular angle fracture including the third molar may influence on post operative infection whether the third molar is in impacted or extracted state when reduction of fracture site is operated. The presence or absence and degree of impaction of the mandibular third molar were assessed for each patient and were related to the occurrence of the mandibular angle fracture. The extraction or non extraction of the mandibular third molar were related to the occurrence of the post operative infection in the reduction of mandibular angle fractures. In the presence of mandibular third molar, the possibility of mandibular angle fractures were relatively common. When viewing the mandibular third molar at occlusal plane, the possibility of mandibular angle fractures were high in the class C group. The possibility of mandibular angle fractures were high in the mesial angulation and partial impaction. There was a statistically significant difference(P<0.05). In complete erupted mandibular third molar, the possibility of post operative infection occurs quite often, but there was no statistical significant difference(P>0.05). In the extracted or non extracted of mandibular third molar, the post operative infection showed no statistical significant difference(P>0.05). With the results mentioned above, mandibular third molar was significantly more susceptible to mandibular angle fracture. In the reduction of mandibular angle fracture, it was recommended that mandibular third molar should be extracted especially in case of pericoronitis, periodontitis and other infections.

• 대한치과의사협회지
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• 제58권2호
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• pp.114-122
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• 2020

Aesthetic facial profile is mainly determined by cultural background. In some countries, prominent mandibular angle is considered as characteristics, whereas it is considered as unattractive in East Asian countries. Therefore, reduction surgery for prominent mandibular angle is one of the popular cosmetic surgery in theses countries. The anatomical component of the mandibular angle consists of masseter muscle and the angular part of the mandibular ramus. Thus, the mandibular angle reduction can be performed by myotomy or bone reduction or both.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제29권4호
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• pp.226-231
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• 2003

The contour of mandibular angle is important for facial esthetics in the oriental population, because the wide and square face is thought to have had an unhappy life. A prominent mandibular angle produces a characteristics quardrangle, coase, and muscular appearance. So, uni- or bi-lateral mandibular angle reduction is usually performed. However, there is little guideline for bi-lateral angle reduction. So, this study was to investigate the pattern of Korean mandibular angle for bi-lateral mandibular angle reduction as guideline. This study was included 66 adult men and women over 19 years old who are having the normal mandibular angle. We measured the posterior border, angle, and inferior border of mandible using cephalometric view. The results of study was as followed : 1. The ratio of posterior mandible was 96.6, 97.3% in male, and 103.0, 106.0% in female. 2. The ratio of mandibular angle(R1-Go/R1-R2) was 120.2% in male, and 117.3% in female. 3. The ratio of inferior mandible(D5, 6, 7, E, F, G/D4) was 97.3, 90.9, 79.5, 65.2, 57.8, 46.9% in male, and 98.5, 91.2, 80.5, 67.6, 59.1, 50.2% in female. The results of this study should be useful to decide accurate amount of reduction.

• Journal of Oral Medicine and Pain
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• 제25권2호
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• pp.173-189
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• 2000

The purpose of this study was to evaluate the effect of specific head positions on the mandibular rotational torque movements in maximum mouth opening, protrusion and lateral excursion. Thirty dental students without any sign or symptom of temporomandibular disorders(TMDs) were included as a control group and 90 patients with TMDs were selected and examined by routine diagnostic procedure for TMDs including radiographs and were classified into 3 subgroups : disc displacement with reduction, disc displacement without reduction, and degenerative joint disease. Mandibular rotational torque movements were observed in four head postures: upright head posture(NHP), upward head posture(UHP), downward head posture(DHP), and forward head posture(FHP). For UHP, the head was inclined 30 degrees upward: for DHP, the head was inclined 30 degrees downward: for FHP, the head was positioned 4cm forward. These positions were adjusted with the use of cervical range-of-motion instrumentation(CROM, Performance Attainment Inc., St. Paul, U.S.A.). Mandibular rotational torque movements were monitored with the Rotate program of BioPAK system (Bioresearch Inc., WI, U.S.A.). The rotational torque movements in frontal and horizontal plane during mandibular border movement were recorded with two parameters: frontal rotational torque angle and horizontal rotational torque angle. The data obtained was analyzed by the SAS/Stat program. The obtained results were as follows : 1. The control group showed significantly larger mandibular rotational angles in UHP than those in DHP and FHP during maximum mouth opening in both frontal and horizontal planes. Disc displacement with reduction group showed significantly larger mandibular rotational angles in DHP and FHP than those in NHP during lateral excursion to the affected and non-affected sides in both frontal and horizontal planes(p<0.05). 2. Disc displacement without reduction group showed significantly larger mandibular rotational angles in FHP than those in any other head postures during maximum mouth opening as well as lateral excursion to the affected and non-affected sides in both frontal and horizontal planes. Degenerative joint disease group showed significantly larger mandibular rotational angles in FHP than those in any other head postures during maximum mouth opening, protrusion and lateral excursion in both frontal and horizontal planes(p<0.05). 3. In NHP, mandibular rotational angle of the control group was significantly larger than that of any other patient subgroups. Mandibular rotational angle of disc displacement with reduction group was significantly larger than that of disc displacement without reduction group during maximum mouth opening in the frontal plane. Mandibular rotational angle of disc displacement without reduction group was significantly larger than that of disc displacement with reduction group or degenerative joint disease group during maximum mouth opening in the horizontal plane(p<0.05). 4. In NHP, mandibular rotational angles of disc displacement without reduction group were significantly larger than those of the control group or disc displacement with reduction group during lateral excursion to the affected side in both frontal and horizontal planes. Mandibular rotational angle of disc displacement without reduction group was significantly smaller than that of the control group during lateral excursion to the non-affected side in frontal plane. Mandibular rotational angle of disc displacement without reduction group was significantly larger than that of disc displacement with reduction group during lateral excursion to the non-affected side in the horizontal plane(p<0.05). 5. In NHP, mandibular rotational angle of the control group was significantly smaller than that of disc displacement with reduction group or disc displacement without reduction group during protrusion in the frontal plane. Mandibular rotational angle of disc displacement without reduction group was significantly larger than that of the disc displacement with reduction group or degenerative joint disease group during protrusion in the horizontal plane. Mandibular rotational angle of the control group was significantly smaller than that of disc displacement without reduction group or degenerative joint disease group during protrusion in the horizontal plane(p<0.05). 6. In NHP, disc displacement without reduction group and degenerative joint disease group showed significantly larger mandibular rotational angles during lateral excursion to the affected side than during lateral excursion to the non-affected side in both frontal and horizontal planes(p<0.05). The findings indicate that changes in head posture can influence mandibular rotational torque movements. The more advanced state is a progressive stage of TMDs, the more influenced by FHP are mandibular rotational torque movements of the patients with TMDs.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제43권4호
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• pp.239-246
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• 2017

Objectives: This paper proposes Han's ratio as an objective and quantitative comparative result obtained from pre and postoperative data in patients with a mandibular angle reduction. Materials and Methods: Thirty patients, 12 men and 18 women, who visited the Department of Oral and Maxillofacial Surgery with the chief complaints of skeletal mandibular prognathism and prominent mandibular angle were selected. The subjects were classified into 3 groups according to the types of surgical procedures involved. Group A consisted of patients who underwent mandibular angle resection and mandibular setback. Group B was comprised of patients with mandibular angle resection, mandibular setback and genioplasty. Group C consisted of patients with mandibular angle resection, mandibular setback, Le Fort I osteotomy, and genioplasty. The landmarks placed in pre and postoperative frontal photographs were used to obtain the Han's ratio in each group. The Han's ratios were compared pre- and postoperation and according to the surgical techniques applied. Results: Of the 3 groups who had undergone a mandibular angle resection, all showed a statistically significant increase in Han's ratio. On the other hand, there was no statistically significant difference based on the surgical techniques used. Conclusion: The ratio of the lateral lower face proposed in this study is a potential indicator of postoperative esthetic enhancement in mandibular angle reduction surgery.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제36권5호
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• pp.201-206
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• 2014

Purpose: To establish management protocol for mandibular angle fracture, we describe pertinent factors including cause, impacted third molar and recent treatment tendency. Methods: We examined the records of 62 patients who had unilateral mandibular angle fracture. Sixty patients who had open reduction surgery were examined at postoperative weeks 1, 4, 8, 12, and 28. Results: Left mandibular angle fracture is frequent in younger males. Presence of the mandibular third molar can increase fracture risk. Because of attached muscle, favorable fractures occurred primarily in the mandibular angle area. Conclusion: Extracting the mandibular third molar can prevent angle fractures, and open reduction with only one plate adaptation is generally the proper treatment method for mandibular angle fracture.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제33권4호
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• pp.397-400
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• 2007

In an open reduction of the mandibular angle fracture, it is crucial to approximate each fracture segment as closer as possible for the reduction of the healing period. In this case report, we proposed a new technique for the mandibular angle fracture. This was designed to minimize the gap between two separated segments using mini-implants and surgical wires. Mini-implants were placed around the fracture line, followed by wire ligation to minimize the fracture gap. And then internal fixation was easily employed with plates and screws. The advantages of this technique were reduced time for operation, the promotion of healing, rapid functional recovery, and few complications.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제32권2호
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• pp.132-140
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• 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
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• 제29권4호
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• pp.340-352
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• 2007

In this systematic review on bone reduction procedures for the correction of the prominent mandibular angle, we collected and sorted the methods. The strength and weakness, indication, complication, and final esthetic result of each method were evaluated. After searching and filtering the literatures on the base of inclusion criteria, 9 eligible case series studies were included in this study. There were 3 types of curved ostectomies and 4 types of lateral cortical ostectomies. Surgical procedures for curved ostectomies were divided into 2 types. One was single curved ostectomy and the other was multistaged curved ostectomy. Lateral cortical ostectomies reported were all similar to sagittal split ramus osteotomy. The complications reported in the included studies were scarce, but curved ostectomies may be able to induce many complications. The prominent mandibular angle must be analyzed in the lateral dimension and frontal dimension, and curved ostectomy can reduce the mandibular angle laterally while lateral cortical ostectomy can reduce the bigonial distance frontally. Because curved ostectomies can induce complications and unnaturally large mandibular angle while can not reduce bigonial distance efficiently, the current trend for the angle reduction procedure is lateral cortical ostectomies.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제43권1호
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• pp.46-48
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• 2017

A patient, who underwent partial masseter muscle resection and mandibular angle reduction at a plastic surgery clinic, visited this hospital with major complaints of trismus and dysesthesia. A secondary angle formation due to a wrong surgical method was observed via clinical and radiological examinations, and the patient complained of trismus due to the postoperative scars and muscular atrophy caused by the masseter muscle resection. The need for a masseter muscle resection in square jaw patients must be approached with caution. In addition, surgical techniques must be carefully selected in order to prevent complications, and obtain effective and satisfactory surgery results.