두부 위치에 따른 하악 과두의 파노라마상

김정화,최순철 大韓口腔顎顔面 放射線學會 1990 Imaging Science in Dentistry Vol.20 No.2

Panoramic radiography is convenient in clinic and visualizes those areas which other technique do not give. But the technique has limitation of image distortion which results from the relationship of the ramus to the focal trough and from the direction of the central ray. This study is, using 7 dry skulls, to determine the effect of rotation of patient's head on reducing those distortion and determine the magnification ratio of images of mandibular condyle in rotated patient head postition. The obtained results were as follows : 1. Generally, in panoramic radiography the anterolateral portion of the mandibular condyle was best to be visualized. 2. There are no significant difference between the image readability of anteromedial portion and that of anterocentral portion of the mandibular condyle. 3. Anterolateral portion of the mandibular condyle was better visualized in rotated head position by 20 degree or horizontal condylar inclination than in conventional position or in rotated head position by 10 degree. 4. The magnification ratio of the anteroposterior diameter in the image of mandibular condyle was least in the rotated head position by horizontal inclination of the mandibular condyle and was largest by 20 degree.

Condyle dislocation following mandibular reconstruction using a fibula free flap: complication cases

Kang, Sang-Hoon,Lee, Sanghoon,Nam, Woong Korean Association of Maxillofacial Plastic and Re 2019 Maxillofacial Plastic Reconstructive Surgery Vol.41 No.-

Background: Condylar dislocation can arise as a complication in patients who required mandibular and/or condylar reconstruction and were operated on with fibula free flap (FFF) using surgical guides designed using simulation surgery. Surgeons should be aware of the complications in these present cases when planning and performing reconstructions as well as predicting prognoses. Cases presentation: Two cases showed condylar dislocation in mandibular reconstruction using a FFF fixed with a reconstruction plate. Three cases showed condylar dislocation in mandibular reconstruction using a fibula free flap fixed with a mini-plate. Conclusion: Despite the lack of clinical symptoms in these cases following mandibular reconstruction using an FFF, the mandibular condyle was severely displaced away from the glenoid fossa. A surgeon must have sufficient time to consider the use of a long flap with thickness similar to that of the mandible, ways to minimize span and bending, and methods of fixation. The patient, moreover, should be educated on condylar dislocation. Customized CAD/CAM-prototyped temporomandibular condyle-connected plates may be a good alternative even if virtual simulation surgery is to be performed before surgery. These considerations may help reduce the incidence of complications after mandibular reconstruction.

편측저작시 하악골 과두의 응력분포에 관한 삼차원 유한요소분석적 연군

남도현,허성주,김광남,Nam, Do-Hyun,Hoe, Seong-Joo,Kim, Kwang-Nam 대한치과보철학회 1997 대한치과보철학회지 Vol.35 No.3

It has been held that excessive mechanical forces to the osseous and soft tissues of the TMJ result in joint dysfunction. Understanding the stress pattern on TMJ is very important in TMJ research. But, it is very difficult to measure directly the biomechanical stress distribution in the TMJ when the mandible is loaded. Therefore, stress distribution in the TMJ during functional movement was studied through animal experiment or mathematical model. It was observed and compared the stress distribution occuring in the working and balancing condyle when lower right canine, lower right first molar and lower right second molar were clenched by the three dimensional finite element analysis. Also, stress distribution in the working and balancing condyles were observed and compared when $20^{\circ}$ forward and buccal bite forces were applied to the first molar. The results were as follows : 1. Stress distribution in the condyles during unilateral clenching of the first molar, second molar, canine showed no difference. In the working condyle, tensile force was concentrated on the lateral aspect of the condylar articular surface and condylar neck. And compressive force was concentrated on the anteromedial and lateral aspect of condyle. In the balancing condyle, tensile and compressive forces were concentrated on the lateral aspect of the condylar articular surface and stress transmission to the temporal bone was not observed. 2. When lateral forces were applied to the first molar, tensile forces were concentrated on the medial aspect of the condylar neck and condylar posterior surface in working and balancing condyle. Compressive force was concentrated on the anteromedial and lateral surface of the condyle and stress transmission to the temporal bone was not observed. 3. During unilateral clenching, stress in the working condyle decreased as the occlusal load moved posteriorly while the stress in the balancing condyle increased. when lateral force was applied to first molar, the incremental amount of stress was greater than vertical load. 4. During unilateral clenching, the average balancing/working condyle stress ratio was 2.52. There was a greater concentration of stress in the balancing condyle. The ratio increased as the occlusal load moved posteriorly and decreased considerably when lateral forces were applied to the first molar.

하악골 골절의 원인과 양상에 관한 연구

정일혁,한기덕,서제덕,황경균,Chung, Il-Hyuk,Han, Ki-Deok,Suh, Je-Duck,Hwang, Kyung-Gyun 대한악안면성형재건외과학회 2005 Maxillofacial Plastic Reconstructive Surgery Vol.27 No.5

This study investigated the mandibular fractures that were treated at the Seoul National University Boramae Hospital in order to analyze the characteristics of mandibular fractures and the relationship between the causes and injury patterns. A total of 141 patients with mandibular fractures who were treated between 1996 and 2004 were analyzed retrospectively. The male to female ratio in the patient group was 5.13:1, and the mean age was 33.7 years. The most common etiologic factor was assaults (45.4%), and which was followed by activities associated with daily-life (40.4%) includeding falls, stumbling, collisions, and traffic accidents (11.3%). Single fracture sites were present in 75 patients (53.2%), two or more fracture sites were observed in other patients, and a total of 211 fracture sites were observed. The mandibular angle fractures (46.7%) was the most common in case of single fractures, and symphysis and angle fractures (45.4%) was most common in multiple fractures. Through out overall fracture sites, the most common fracture site was the symphysis (41.2%), followed by the angle (32.2%) and condyle (18.5%). Among assault and falls-related injuries, the common involving sites were the symphysis, and followed by the body and condyle. In case of traffic accidents, the symphysis fracture was the most common, and which was followed by the condyle and angle fractures. This study documented the characteristics of the mandibular fractures. The results demonstrate that preventive measures according to these characteristics will need to be implemented in order to minimize the risk of maxillofacial injuries. 저자 등은 1996년 1월부터 2004년 12월까지 서울대학교 보라매병원 구강악안면외과에서 치료받은 141명의 하악골 골절 환자의 임상적 연구를 통하여 다음을 알 수 있었다. 1. 전체 환자에서 남,녀 성별 발생빈도는 5.13대 1로 남자에서 호발 하였으며, 연령대별로는 20대에서 가장 빈발하였고 (30.5%), 그 다음 30대, 40대 (22.7%) 순이었다. 2. 하악골 골절의 원인으로 폭행 (45.4%), 낙상, 추락 및 충돌 (40.4%), 교통사고 (11.3%) 순이었다. 3. 골절부의 위치는 하악 정중부 (41.2%), 우각부(32.2%), 과두부 골절(18.5%)의 순으로 나타났으며, 단일 골절의 경우 하악 우각부 골절이 (46.7%)로 가장 많았고, 두 군데 이상의 골절의 하악 정중부 및 우각부 동시 골절이 가장 많았다 (45.5%). 4. 교통사고로 인한 하악 골절은 정중부, 과두부, 우각부 골절의 순으로 발생 빈도를 보였고, 폭력과 낙상, 추락 및 충돌 등으로 인한 골절의 경우 정중부, 우각부, 과두부 골절 순으로 발생빈도를 보였다.

Cone beam형 전산화단층촬영법을 이용한 하악과두의 골변화에 관한 연구

이지운,김형섭,송주섭,김경아,고광준 대한구강악안면방사선학회 2007 Imaging Science in Dentistry Vol.37 No.3

Purpose : To assess bone changes of mandibular condyle using cone beam computed tomography (CBCT) in temporomandibular disorder (TMD) Patients. Materials and Methods : 314 temporomandibular joints (TMJs) images of 163 TMD patients were examined at the Department of Oral and Maxillofacial Radiology, Chonbuk National University. The images were obtained by PSR9000N (Asahi Roentgen Co., Japan) and reconstructed by using Asahivision software (Asahi Roentgen Co.,Japan). The CBCT images were examined three times with four weeks interval by three radiologists. Bone changes of mandibular condyle such as flattening, sclerosis, erosion and osteophyte formation were observed in sagittal, axial, coronal and 3 dimensional images of the mandibular condyle. The statistical analysis was performed using SPSS 12.0. Intra-and interobserver agreement were performed by 3 radiologists without the knowledge of clinical information. Results : Osteophyte (2.9%) was found more frequently on anterior surface of the mandibular condyle. Erosion (31.8%) was found more frequently on anterior and medial surfaces of the mandibular condyle. The intraobserver agreement was good to excellent(k=0.78-0.84), but interobserver agreement was fair(k=0.45). Conclusion : CBCT can provide high qualified images of bone changes of the TMJ with axial, coronal and 3 dimensional images.

Anatomical and Functional Recovery of Intracapsular Fractures of the Mandibular Condyle: Analysis of 124 Cases after Closed Treatment

Lee, Jong-Sung,Jeon, Eun-Gyu,Seol, Guk-Jin,Choi, So-Young,Kim, Jin-Wook,Kwon, Tae-Geon,Paeng, Jun-Young Korean Association of Maxillofacial Plastic and Re 2014 Maxillofacial Plastic Reconstructive Surgery Vol.36 No.6

Purpose: The purpose of this study is to evaluate the influence of intracapsular fracture lines of the mandibular condyle on the anatomical and functional recovery after non-surgical closed treatment. Methods: Clinical and radiological follow-up of 124 patients with intracapsular fractures of the mandibular condyle was performed after closed treatment between 2005 and 2012. The intracapsular fractures were classified into three categories: type A (medial condylar pole fracture), type B (lateral condylar pole fracture with loss of vertical height) and type M (multiple fragments or comminuted fracture). Results: By radiological finding, fracture types B and M lost up to 24% vertical height of the mandibular condyle compared to the height on the opposite side. In Type M, moderate to severe dysfunction was observed in 33% of the cases. Bilateral fractures were significantly associated with the risk of temporomandibular joint (TMJ) dysfunction in fracture types A and B. Bilateral fracture and TMJ dysfunction were not statistically significantly associated in type M fractures. Conclusion: Most of the mandibular intracapsular condylar fractures recovered acceptably after conservative non-surgical treatment with functional rehabilitation, even with some anatomical shortening of the condylar height. The poor functional recovery encountered in type M fractures, especially in cases with additional fracture sites and bilateral fractures, points up the limitation of closed treatment in such cases.

발육중인 생쥐 하악 과두에서 연골 및 골의 특이 유전자 발현

지국섭,윤영주,박주철,김광원 대한치과교정학회 2004 대한치과교정학회지 Vol.34 No.2

하악과두 연골이 발생하고 분화하는 과정에서 나타내는 특성을 규명하기 위하여, 발생 16, 18일과 출생 1일, 5일, 10일, 20일 및 30일 후의 ICR생쥐의 하악과두를 형태학적으로 분석하고, 생쥐 Ⅰ형, Ⅱ형, X형 교원질, Indian hedgehog(IHH) 및 BMP-4 등의 mRNA 발현을 in-situ hybridization 방법으로 연구하였다. 1. 생쥐 Ⅰ형 및 Ⅱ형 교원질 mRNA는 하악과두의 발생 및 성장과정에서 모두 발현되었다. Ⅰ형 교원질 mRNA는 휴지층과 증식층의 상부에서 관찰된 반면 Ⅱ형 교원질은 휴지층과 증식층 그리고 비대연골층의 상부에서 관찰되었다. 2. 하악과두 연골은 성장에 따라 비대연골층이 계속 증가하는 소견을 보였으며, 비대 연골층의 세포들은 특징적으로 X형 교원질 mRNA의 발현을 보였다. 3. BMP-4 mRNA는 하악과두 연골 원기와 골화중인 하악골체에서 모두 발현되었다. 4. IHH mRNA는 하악과두의 발생과정에서 증식 연골층의 하부와 비대연골층의 상부에서 선택적으로 관찰되었다. It has not been elucidated whether the initiation of condylar development of the mandible is related with the periosteum of the mandible, or if it derives from a separate programmed blastema not related with the mandible. Also, although the mandibular condylar cartilage is known to promote growth, few studies have dealt with molecular-biologic mechanisms such as the expression of specific genes according to the differentiation of the mandibular condyle. To elucidate the unique cellular characteristics, development, and differentiation process of the mandibular condyle, an examination of expressions of genes characteristic of cartilage and bone were carried out using RT-PCR and mRNA in situ hybridization. 1. Type?collagen mRNA was detected with type Ⅱ collagen mRNA in the differentiation and growth process of the cartilage of the mandibular condyle. Type Ⅱ collagen mRNA was demonstrated in the whole resting and upper part of the proliferative zone, whereas type Ⅱ collgen mRNA was observed in the resting, proliferative and upper hypertrophic cartilage zone of the mandibular condyle. 2. The condylar cartilage rapidly increased in size due to the accumulation of hypertrophic chondrocytes as characterized by the expression of type Ⅱ collagen mRNA during postnatal development. 3. BMP-4 mRNA was present in the anlage of the future condylar process and also in the ossifying mandibular body. 4. IHH mRNA was limited exclusively to the lower part of the proliferative zone and the upper part of the hypertrophic cartilage zone during condylar development. These findings were different from those in the growth-plate cartilage of the long bone, indicating a characteristic feature of the differentiation of the chondrocytes in the condylar cartilage present in prenatal and postnatal development. Furthermore, it was also suggested that chondroblasts of condylar cartilage rapidly differentiate into hypertrophic chondrocytes with increased functional Load force such as muscle activity and mastication.

편측저작시 하악골 과두의 응력분포에 관한 삼차원 유한요소분석적 연구

김광남,남도현 대한 두개하악 장애학회 1996 대한두개하악장애학회지 Vol.8 No.2

It has been held that excessive mechanical forces to the osseous and soft tissues of the TMJ result in joint dysfunction. Understanding the stress pattern on TMJ is very important in TMJ research. But, it is very difficult to measure directly the biomechanical stress distribution in the TMJ when the mandible is loaded. Therefore, stress distribution in the TMJ during functional movement was studied through animal experiment or mathematical model. It was observed and compared the stress distribution occuring in the working and balancing condyle when lower right canine, lower right first molar and lower right second molar were clenched by the three dimensional finite element analysis. Also, stress distribution in the working and balancing condyles were observed and compared when 20˚ forward and buccal bite forces were applied to the first molar. The results were as follows : 1. Stress distribution in the condyles during unilateral clenching of the first molar, second molar, canine showed no difference. In the working condyle, tensile force was concentrated on the lateral aspect of the condylar articular surface and condylar neck. And compressive force was concentrated on the anteromedial and lateral aspect of condyle. In the balancing condyle, tensile and compressive forces were concentrated on the lateral aspect of the condylar articular surface and stress transmission to the temporal bone was not observed. 2. When lateral forces were applied to the first molar, tensile forces were concentrated on the medial aspect of the condylar neck and condylar posterior surface in working and balancing condyle. Compressive force was concentrated on the anteromedial and lateral surface of the condyle and stress transmission to the temporal bone was not observed. 3. During unilateral clenching, stress in the working condyle decreased as the occlusal load moved posteriorly while the stress in the balancing condyle increased, when lateral force was applied to first molar, the incremental amount of stress was greater than vertical load. 4. During unilateral clenching, the average balancing/working condyle stress ratio was 2.52. There was a greater concentration of stress in the balancing condyle. The ratio increased as the occlusal load moved posteriorly and decreased considerably when lateral forces were applied to the first molar.

Post-traumatic bifid mandibular condyle: A case report and literature review

Woo, Min-Ho,Yoon, Kyu-Ho,Park, Kwan-Soo,Park, Jae-An Korean Academy of Oral and Maxillofacial Radiology 2016 Imaging Science in Dentistry Vol.46 No.3

Bifid mandibular condyle (BMC) is an uncommon morphological variant of the mandibular condyle. Although authors have proposed various etiologies for BMC, no consensus has emerged. In addition, varying findings have been reported regarding the epidemiological parameters of BMC (e.g., prevalence, gender ratio, and age), possibly due to its low incidence. BMC is occasionally associated with symptoms of the temporomandibular joint, such as ankylosis, pain, and trismus; however, it is difficult to detect this condition on conventional radiographs. This study reports a case of BMC with radiographic findings, and reviews the literature on the epidemiology of BMC.

Post-traumatic bifid mandibular condyle: A case report and literature review

우민호,윤규호,박관수,박재안 대한영상치의학회 2016 Imaging Science in Dentistry Vol.46 No.3

Bifid mandibular condyle (BMC) is an uncommon morphological variant of the mandibular condyle. Although authors have proposed various etiologies for BMC, no consensus has emerged. In addition, varying findings have been reported regarding the epidemiological parameters of BMC (e.g., prevalence, gender ratio, and age), possibly due to its low incidence. BMC is occasionally associated with symptoms of the temporomandibular joint, such as ankylosis, pain, and trismus; however, it is difficult to detect this condition on conventional radiographs. This study reports a case of BMC with radiographic findings, and reviews the literature on the epidemiology of BMC.