• The Journal of Advanced Prosthodontics
• /
• 제6권6호
• /
• pp.483-490
• /
• 2014

PURPOSE. The purpose of this study was to determine the average facial proportions and mandibular movement capacity of 316 first-year dental students who carefully recorded them on each other. MATERIALS AND METHODS. This early exacting clinical experience was closely supervised by the authors in Columbus, Ohio during 1969-70. Five vertical and six horizontal distances were measured on each subject's face. An ala-tragus line and an occlusal line were drawn on the left side of the face to determine if these two lines were parallel. Measurements of mandibular movements involved maximum normal and hinge opening at the incisors and maximum amounts of right, left lateral and protrusive excursions of the mandible. RESULTS. The ala width and distance between the tips of upper right and left canine cusps averaged (35.2 mm and 34.8 mm) but with very large individual variations. The distance between ala to occlusal plane lines was 29.9 mm at the tragus and 31.3 mm near the ala. The angle between orbitale and ala-tragus averaged 13.6 degrees. CONCLUSION. The upper lip length was the most variable and the distance between the pupils was the most stable of the eleven facial measurements. The ala-tragus line and the occlusal plane lines were for all practical purposes parallel. Maximum jaw opening averaged 51.2 mm which was 3.0 times larger than maximal hinge opening of 17.2 mm. The maximum right plus left side jaw excursions (9.2 and 9.4 mm) totaled 18.6 mm, 2.3 times more than the 8.0 mm mean maximum forward protrusion.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제39권
• /
• pp.22.1-22.9
• /
• 2017

Background: Two-jaw surgery including mandibular and maxillary backward movement procedures are commonly performed to correct class III malocclusion. Bimaxillary surgery can reposition the maxillofacial bone together with soft tissue, such as the soft palate and the tongue base. We analyzed changes of pharyngeal airway narrowing to ascertain clinical correlations with the prevalence of snoring after two-jaw surgery. Methods: A prospective clinical study was designed including a survey on snoring and three-dimensional (3D) computed tomography (CT) in class III malocclusion subjects before and after bimaxillary surgery. We conducted an analysis on changes of the posterior pharyngeal space find out clinical correlations with the prevalence of snoring. Results: Among 67 subjects, 12 subjects complained about snoring 5 weeks after the surgical correction, and examining the 12 subjects after 6 months, 6 patients complained about the snoring. The current findings demonstrated the attenuation of the largest transverse width (LTW), anteroposterior length (APL), and cross-sectional area (CSA) following bimaxillary surgery given to class III malocclusion patients, particularly at the retropalatal level. The average distance of maxillary posterior movements were measured to be relatively higher (horizontal distance 3.9 mm, vertical distance 2.6 mm) in case of new snorers. Conclusions: This study found that bimaxillary surgery could lead to the narrowing of upper airway at the retropalatal or retroglossal level as well as triggering snoring in subjects with class III malocclusion. Based on the current clinical findings, we also found that upper airway narrowing at retropalatal level may contribute to increasing the probability of snoring and that polysonography may need to be performed before orthognathic surgery in subjects with class III malocclusion.

• 대한치과교정학회지
• /
• 제43권1호
• /
• pp.42-52
• /
• 2013

The aim of this paper was to propose a new method of bimaxillary orthognathic surgery planning and model surgery based on the concept of 6 degrees of freedom (DOF). A 22-year-old man with Class III malocclusion was referred to our clinic with complaints of facial deformity and chewing difficulty. To correct a prognathic mandible, facial asymmetry, flat occlusal plane angle, labioversion of the maxillary central incisors, and concavity of the facial profile, bimaxillary orthognathic surgery was planned. After preoperative orthodontic treatment, surgical planning based on the concept of 6 DOF was performed on a surgical treatment objective drawing, and a Jeon's model surgery chart (JMSC) was prepared. Model surgery was performed with Jeon's orthognathic surgery simulator (JOSS) using the JMSC, and an interim wafer was fabricated. Le Fort I osteotomy, bilateral sagittal split ramus osteotomy, and malar augmentation were performed. The patient received lateral cephalometric and posteroanterior cephalometric analysis in postretention for 1 year. The follow-up results were determined to be satisfactory, and skeletal relapse did not occur after 1.5 years of surgery. When maxillary and mandibular models are considered as rigid bodies, and their state of motion is described in a quantitative manner based on 6 DOF, sharing of exact information on locational movement in 3-dimensional space is possible. The use of JMSC and JOSS will actualize accurate communication and performance of model surgery among clinicians based on objective measurements.

• Journal of Oral Medicine and Pain
• /
• 제38권4호
• /
• pp.333-338
• /
• 2013

Purpose: 특정한 형태의 이명은 그 발생에 있어서 청각계와 체성감각계의 상호작용이 핵심적인 역할을 하고 있음을 시사하는 증거들이 지속적으로 연구되어 발표되고 있다. 이러한 맥락에서 본 연구는 턱의 운동이 이명에 미치는 영향을 조사하고자 계획되었다. Methods: 163명 이명 환자의 217귀를 대상으로 순음청력검사, 이명의 특성에 대한 설문조사, 이명의 크기, 지속시간 및 괴로운 정도에 대한 시각사상척도(visual analogue scale) 조사와 함께 9 항목의 턱관절의 등척성 운동에 따른 이명의 크기 변화를 조사하는 이명의 체성조절 검사를 시행하였다. Results: 체성조절 검사를 시행한 이명 환자의 217귀 중 125귀(57.6 %)에서 이명의 크기가 변함을 관찰할 수 있었다. 일측성 이명 109귀중 70귀(64.2%)에서 체성조절에 반응하여 양측성 이명 108귀중 55귀(50.9%)의 반응보다 유의하게 높은 빈도를 보였다(p<0.05). 검사 항목 모두에서 이명의 크기 증가가 감소보다 더 자주 관찰되었고, 크기 증가의 빈도는 6.7-15.4%로 개구 및 이악물기 항목에서 가장 자주 이명의 크기 증가가 유발되었다. Conclusion: 본 연구 결과, 턱의 운동은 이명을 악화 혹은 유발시킬 수 있으며, 체성조절 검사는 턱 관절의 자극이 이명의 유발 및 악화요인 인가를 평가하는 방법으로 활용할 수 있을 것으로 생각된다.

• The Korean Journal of Physiology
• /
• 제3권1호
• /
• pp.33-44
• /
• 1969

Electoromyographic studies were performed on the action of the muscles of the temporomandibular joints following exfoliation of the deciduous teeth. The subjects examined, being 50 children. between the age of 6 and 13 years, divided into 5 groups. They were; 1) Deciduous dentition were complete in the first group. 2) Deciduous incisors were missing in either upper or lower jaw in the second group. 3) Deciduous canine and molars were missing in the left side of either upper or lower jaw in the third group. 4) Deciduous canine and molars were missing in the right side of either upper or lower jaw in the fourth group. 5) Permanent dentition completed in the fifth group(except third molars). Electromyogram was recorded with 4 channel polygraph (Grass model VII modified for 7P3). Electrodes which were the cup-typed gold discs, 9 millimeters in the diameter, were located on the anterior, middle and posterior lobes of the temporal muscles, and also on the superficial and deep layers of the masseter muscles. Paired electrodes were held by electrode cream so that they were pressed on the skin surface at right angle, adhesive tape being used to anchor them. The distance of the pair electrodes was about 5 millimeters. The results obtained were as follow: 1) In rest position of mandible; All groups showed slight, electrical activities in the muscles involved, but in the middle lobe of temporal muscle they were slightly higher. 2) In molar occlusion of mandible; High activity-anterior lobe of temporal muscle and superficial layer of masseter muscle. Moderate activity-deep layer of masseter muscle. Low activity-middle and posterior lobes of masseter muscle. There were no differences among the first, the second and the fifth groups. In the third group the muscle activity was weaker than that of the right, and in the fourth group opposite characteristics was revealed. 3) In incisal bite of mandreble; Hight activity-superficial layer of masseter muscle. Modertae activity-deep layer of masseter muscle. Low activity-anterior, middle and posterior lobes of temporal muscle. The first, the third, the fourth and the fifth groups showed no differences but the second group showed less activity than those of others. 4) In protrusion of mandible; High activity-deep layer of masseter muscle Moderate activity-superficial layer of masseter muscle. Low activity-anterior, middle and posterior lobes of temporal muscle. In the first, the fourth and the fifth groups, there were no differences in the activities, but the second group showed less activity than the others. 5) In retrusion of mandible; High activity-deep layer of masseter muscle. Moderate activity-superficial layer of masseter muscle. Low activity-anterior, middle and posterior lobes of temporal muscle. In the first, the third, the fourth and the fifth groups, there were no differences but the second group showed less activity than the others. 6) In lateral excursion of the mandible (either direction); High activity-posterior lobe of temporal muscle. Moderate activity-anterior and middle lobes of temporal muscle. Low activity-superficial and deep layers of masseter muscle. The muscle action potentials were weaker than those of the right side in the third group and vice ver'sa in the fourth group. 7) In chewing movement; Temporal muscle activities were higher than those of masseter, especially in the middle lobe of temporal muscle the activity was highest. Right side muscle activities were higher than those of the left in the third group and, on the contrary, the left side was dominant over the right in the fourth group.

• 대한치과교정학회지
• /
• 제50권3호
• /
• pp.157-169
• /
• 2020

Objective: The aim of this retrospective study was to evaluate the pre- and postsurgical bone densities at alveolar and extra-alveolar sites following two-jaw orthognathic surgery. Methods: The sample consisted of 10 patients (mean age, 23.2 years; range, 18.0-27.8 years; 8 males, 2 females) who underwent two-jaw orthognathic surgery. A three-dimensional imaging program (Invivo 5) was used with multidetector computed tomography images taken pre- and postoperatively (obtained 32.3 ± 6.0 days before surgery and 5.8 ± 2.6 days after surgery, respectively) for the measurement of bone densities at the following sites: (1) alveolar bone in the maxilla and mandible, (2) extra-alveolar sites, such as the top of the head, menton (Me), condyle, and the fourth cervical vertebrae (C4). Results: When pre- and postsurgical bone densities were compared, an overall tendency of decrease in bone density was noted. Statistically significant reductions were observed in the densities of cancellous bone at several areas of the maxillary alveolar bone; cortical and cancellous bone in most areas of the mandibular alveolar bone; cortical bone in Me; and cancellous bone in C4. There was no statistically significant difference in bone density in relation to the depth of the alveolar bone. In a comparison of the bone densities between groups with and without genioplasty, there was almost no statistically significant difference. Conclusions: Accelerated tooth movement following orthognathic surgery may be confirmed with reduced bone density. In addition, this study could offer insights into bone metabolism changes following orthognathic surgery, providing direction for further investigations in this field.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제19권2호
• /
• pp.117-129
• /
• 1997

Recently, combined with social complexity, increment of medical demand and supply and the change of esthetic category, admission and operation of the patients of facial deformity have been changed with annual change. This study was conducted in the concept of helping the overall character of orthognathic surgery in future understood and being an important index in the establishment of better treatment course, through the patient, on whom was operated orthognathic surgery via sagittal split ramal osteotomy in our Dept. of Oral & Maxillofacial Surgery, Chonbuk National University Hospital from 1991. 1. 1 to 1995. 12. 31. The results were obtained as follows. 1. The ratio of male to female was 1 : 1.33 and the ages between 16 and 25 year was 73.6%, and the mean age was 20.4 years. 2. The ratio of setback amount between 6 to 15mm was 84.6% and the advancement amount between 1 to 10mm was 89% and the mean amount of movement was 9.0mm in setback, and 3.6mm in advancement. 3. After removal of maxillomandibular fixation(MMF), the distinction of sex was not statistically significant in ROM. 4. The ROM following methods of fixation was statistically significant in 3rd(P<0.05), 8th, and 12th week(each P<0.01), with faster rehabilitation in rigid fixation which had shorter MMF period. 5. The rehabilitation of ROM following the operation methods was statistically significant in 1st(P<0.05), 2nd, 3rd, 4th, 6th, 8th, and 12th week(each P<0.01) with faster rehabilitation in the case of SSRO than Lefort I / SSRO (Two jaw surgery). 6. The rehabilitation of ROM following directions of mandibular movement did not manifest a statistically significant difference in both setback and advancement.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제33권4호
• /
• pp.319-322
• /
• 2011

Purpose: The purpose of this study was to examine the appropriate degree of set-back of the mandible by evaluating the rate of relapse after surgery. Methods: Among the patients who visited our hospital from January 2002 to January 2007 and who underwent orthognathic surgery, of the patients available for follow-up observation, the rate of relapse after surgery was investigated according to the set-back degree. The patients were divided into groups by the degree of set-back, and relapse was evaluated by the radiographs performed the day after surgery, 6 months after surgery, 1 year after surgery, 2 years after surgery and 3 years after surgery. Results: In cases that exceeded the limit of posterior movement of the mandible (13 mm) or that had the wrong position of the condyle, a greater tendency toward relapse was shown. Conclusion: Based on the results of this study, among the cases that required a large amount of posterior movement of the mandible, two jaw surgeries accompanied by bilateral sagittal split ramus osteotomy (BSSRO) and LeFort I osteotomy are recommended.

• 한국융합학회논문지
• /
• 제7권2호
• /
• pp.53-59
• /
• 2016

뇌전증은 뇌신경세포의 과흥분으로 인한 발작증상을 동반하는 질환이며, 최근 대단위 환자유전체 정보기술의 발달로 인해 뇌전증 발병의 원인으로서 유전자적 요인이 밝혀지고 있다. 본 연구에서는 지적장애 및 뇌전증 증상을 가지는 Miles-Carpenter syndrome (MCS)의 원인유전자에 대한 녹아웃동물을 활용하여 뇌전증 연구모델로 개발하고자 하였다. MCS 녹아웃 제브라피쉬는 억제성 GABA신경세포의 결손으로 인하여 비정상적으로 과다하게 움직이는 표현형을 나타내며, 이는 뇌전증 환자에서 보여지는 발작증상과 매우 유사한 것으로 판명되고 있다. 뇌전증 연구모델로 개발하기 위해, 기존에 알려진 뇌전증 치료제인 레티가빈을 MCS 녹아웃 제브라피쉬에 처리하여 약효를 평가하였으며 증상이 완화되는 것을 확인하였다. 이상의 결과들을 바탕으로 MCS 녹아웃동물이 향후 뇌전증 기전연구를 위한 동물모델로서의 융합적인 활용이 기대된다.

• 대한두개안면성형외과학회지
• /
• 제13권1호
• /
• pp.4-10
• /
• 2012

Purpose: The objective of this retrospective study was to assess the skeletal stability after orthognathic surgery for patients with cleft lip and palate. The soft tissue changes in relation to the skeletal movement were also evaluated. Methods: Thirty one patients with cleft received orthognathic surgery by one surgeon at the Craniofacial Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan. Osseous and soft tissue landmarks were localized on lateral cephalograms taken at preoperative (T0), postoperative (T1), and after completion of orthodontic treatment (T2) stages. Surgical movement (T0.T1) and relapse (T1.T2) were measured and compared. Results: Mean anteroposterior horizontal advancement of maxilla at point A was 5.5 mm, and the mean horizontal relapse was 0.5 mm (9.1%). The degree of horizontal relapse was found to be correlated to the extent of maxillary advancement. Mean vertical lengthening of maxilla at point A was 3.2 mm, and the mean vertical relapse was 0.6 mm (18.8%). All cases had maxillary clockwise rotation with a mean of 4.4 degrees. The ratio for horizontal advancement of nasal tip/anterior nasal spine was 0.54/1, and the ratio of A' point/A point was 0.68/1 and 0.69/1 for the upper vermilion/upper incisor tip. Conclusion: Satisfactory skeletal stability with an acceptable relapse rate was obtained from this study. High soft tissue to skeletal tissue ratios were obtained. Two-jaw surgery, clockwise rotation, rigid fixation, and alar cinch suture appeared to be the contributing factors for favorable results.