• 대한치과보철학회지
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• 제17권1호
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• pp.35-46
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• 1979

A number of experimental studies have been carried out in order to clarify the question as to how temporomandibular joint adapt to the changes of mandibular movement and occlusal equilibration. Recently, the studies on the interrelations between anatomical structure of temporomandibular joint and the state of occlusion have been actively performed in dentistry particularly in prosthodontic field. Author performed extraction of unilateral mandibular molars in 30 mature male rats, and observed histological changes of temporomandibular joint through the light microscope. Following results were obtained. 1. The loss of unilateral teeth gave rise to the changes in the location of condylar head, that is, interior displacement of condylar head in the extraction side and upper displacement in the non-extraction side. 2. Articular disk was compressed by the interior surface of condylar head, resulting in its extension below the condylar neck in the extraction side, and the histological arrangement of the compressed area showed irregular feature. 3. The extension of articular disk below the condylar neck was accompanied with the contraction of muscle fibers which were originated from the articular disk. 4. The cartilage layer of articular fossa to the exterior of the extraction side showed hypertropy. 5. Early in the experiment, the inernal extremity of condylar head of extract ion side showed bone resorption, and cartilage layer of condylar head showed hypertropy. At 12 weeks after experiment, the condylar surface showed flattened, and the cartilage layer of condylar head was replaced by the compact bone. 6. The articular disk showed the formation of pannus in the extraction side as well as in the non-extraction side. 7. The occlusal disturbance due to unilateral missing teeth has brought about the non-inflammatory retrogressive change and osteoarthrotic change late in the experiment.

• Imaging Science in Dentistry
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• 제46권1호
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• pp.25-31
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• 2016

Purpose: This study was performed to evaluate condylar surface changes and remodeling after orthognathic surgery using three-dimensional computed tomography (3D CT) imaging, including comparisons between the right and left sides and between the sexes. Materials and Methods: Forty patients (20 males and 20 females) who underwent multi-detector CT examinations before and after surgery were selected. Three-dimensional images comprising thousands of points on the condylar surface were obtained before and after surgery. For the quantitative assessment of condylar surface changes, point-to-point (preoperative-to-postoperative) distances were calculated using 3D processing software. These point-to-point distances were converted to a color map. In order to evaluate the types of condylar remodeling, the condylar head was divided into six areas (anteromedial, anteromiddle, anterolateral, posteromedial, posteromiddle, and posterolateral areas) and each area was classified into three types of condylar remodeling (bone formation, no change, and bone resorption) based on the color map. Additionally, comparative analyses were performed between the right and left sides and according to sex. Results: The mean of the average point-to-point distances on condylar surface was $0.11{\pm}0.03mm$. Bone resorption occurred more frequently than other types of condylar remodeling, especially in the lateral areas. However, bone formation in the anteromedial area was particularly prominent. No significant difference was found between the right and left condyles, but condylar surface changes in males were significantly larger than in females. Conclusion: This study revealed that condylar remodeling exhibited a tendency towards bone resorption, especially in the lateral areas. Condylar surface changes occurred, but were small.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권3호
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• pp.388-397
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• 2008

The present study was performed to evaluate the function of the mandible according to the pattern of fracture and treatment methods of condylar fractures of the mandible and help operators in making a treatment plan. Sixty patients (average follow-up period was $7.8{\pm}9.4$ months) who were treated for condylar fracture from June, 2002 to May, 2006 at the Department of Oral and Maxillofacial surgery, Chonnam National University Hospital were reviewed. The common causes of the condylar fracture were traffic accident and fall-down (35.0%). In concomitant injuries, laceration was 46.7% and the fracture of the mandibular symphysis was highest incidence (60.0%). The common site of the fracture was the condylar head (47.8%), followed by subcondyle (36.2%) and condylar neck (15.9%). Under 15 years old patients, the closed reduction was performed in 87.5% out of the patients. All of the condylar fragments were fixed to the mandible with titanium miniplates in cases of open reduction. The mean period of intermaxillary fixation (IMF) was $14.2{\pm}6.5$ days in closed reduction and $10.0{\pm}4.2$ days in open reduction. The old patient with bilateral condylar head fractures, who were treated by closed reduction with IMF for 3 weeks, showed the limitation of mandibular movements. But, there was no significant different results between open reduction and closed reduction with the respect of the Helkimo's mandibular mobility index and clinical dysfunction index (DI). Complications, such as fibrous ankylosis and resorption of the mandibular condyle, were not observed in all patients. These results suggest that the good results can be obtained by closed reduction with proper IMF periods and functional exercise in most condylar fractures of the mandible except severely displaced extracapsular fractures.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권5호
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• pp.442-446
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• 2001

Purpose : This study evaluated clinical and radiographic results after open reduction and lag-screw fixation of mandibular condyle fractures. Patients and Methods : 26 patients had been treated by lag-screw fixation for madibular condyle fracures via submandibular approach and follow up for over 6 months. The lag-screw used in this study was designed by Eckelt. Results : Radiographically, resorption of the condyle head found in 4 cases (15%) and minimal displacement of the condyle head was found in 3 cases (12%). Post-operative infection were not found in all cases. Clinically, All patiens had a stable occlusion and normal mouth opening (over 40mm). TMD problems with crepitus or some discomfort encountered in 4 patients but tolerable to the patients. Conclusion : Lag screw fixation can be a good option especially high level condylar fractures, however this procedure must be used in cautiously because of slipping of the fragments and possible to resorption of the fragments.

• 대한치과교정학회지
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• 제52권1호
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• pp.29-41
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• 2022

Objective: Condylar resorption (CR) is one of the major post-surgical complications of orthognathic surgery. This systematic review (SR) aimed to evaluate epidemiological data, risk factors, and therapeutical management of CR. Methods: Six databases were screened by two investigators until September 2020 to obtain all SRs. After reading the titles and abstracts, eligible SRs were determined and data extraction was performed. Using the latest version of A Measurement Tool to Assess Systematic Reviews, the methodological quality of the included SRs was determined. Results: Ten SRs with low or critically-low methodological quality were included in this review. Mandibular hypoplasia on the sagittal plane and hyperdivergent growth pattern on the vertical plane were the most common skeletal alterations in which CR could occur after orthognathic surgery. Post-operative condylar changes were analyzed both on two-dimensional and three-dimensional (3D) radiographic examinations. The incidence of CR was not related to the fixation method. Based on the severity of the pathological conditions, management of CR can include conservative or surgical therapy. Conclusions: Despite the limited evidence in literature, CR is considered a consequence of orthognathic surgery. However, an accurate diagnosis of CR and a better orthognathic surgical planning must include 3D radiographic examinations to improve pre- and post-surgical comparison. Well-designed studies with long-term follow-up and 3D data are needed to clarify the findings of this analysis..

• Maxillofacial Plastic and Reconstructive Surgery
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• 제19권2호
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• pp.157-166
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• 1997

Treatment of condylar fracture is still controversial, but the indication of surgical mangement is increased due to improved fixation methods and surgical techniques. In this article, we report our clinical and radiological results with the use of lag screw osteosynthesis for fixation of fractured mandibular condyle. 12 case of condyle fracture treated by open reduction and fixation with lag screw were monitored for an average of 10 months (range from 6 months to 19 months) postoperatively. The obtained results are as follows : 1. Postoperative maximum mouth opening is achieved over 40mm except one patient. 2. Although slight crepitus and deviation of mandible during mouth opening were found, Temporomandibular joint problem is satisfactory in all but one patient. 3. Distal migration of screw and resorption of fractured fragment were found in each 2 patients, but good functional recovery was achieved in all. According to the above results, we think that lag screw osteosynthesis is relatively indicated in level III or IV condylar fracture.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제23권1호
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• pp.31-39
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• 2001

The purpose of this study is to reveal the factors leading to the problem of unilateral condylar fractures and suggest a treatment guideline of treatment for good prognosis in surgical treatment. The factors can be age, sex, fracture site, degree of displacement, posterior occlusion loss, post-operative alteration of condylar head position, post-operative condylar head resorption, and maxillomandibular fixation period. One hundred and eleven patients with unilateral condylar fractures, who were treated by surgical method from 1990 Feb. to 2000 Feb., were studied. Minimum follow-up period was 6 months. The results were as follows ; 1. In the age group of $41{\sim}60$, females had significantly higher complication rate than males, therefore we must be careful about treatment of female in this age group 2. In level I fractures of the mandibular condyle, because there were abundant complications when the patients were treated with fragment removal, conservative treatment is recommended over the surgical approach. 3. There were no differences in the complication rate, in the level II, III fractures. but were severe complications in the cases of patients treated by Dr.Nam's method or fragment removal. Therefore, open reduction and internal fixation is recommended over Dr.Nam's method or fragment removal. 4. In level IV fractures, open reduction and internal fixation is recommended 5. Although there was a higher complication rate depending on the degree of deviation, there was no correlation between the degree of deviation and development of complications in each level of fracture 6. Because the complication rate was higher in cases of condylar resorption, vertical dimension loss, and alteration of condylar head position, we must make an effort to prevent such complications during treatment

• Maxillofacial Plastic and Reconstructive Surgery
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• 제19권2호
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• pp.167-180
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• 1997

1993년 1월부터 1995년 12월까지 원광 대학교 치과대학 구강악안면외과에 하악 과두 골절을 주소로 내원한 환자중 관혈적 정복술 적응증에 해당되는 79명의 환자에 대하여 관혈적 정복술을 시행하였다(이 중 25명은 Dr. 남씨법을 행한 환자임). 평균 환자 나이는 32.5세(8-65세)이었으며 환자 관찰기간은 약 18.4개월(3-28개월)이었다. 62명(81%)에서 편측 과두 골절 양상이었으며, 57명(72%) 환자가 하악골내 다른 부위와 연관되어 골절되었고 이중 47명(59%)에서 정중부와 관련되어 골절되었다. 환자 나이, 골절된 과두의 심한 정도, 임상 증상, 방사선 사진상 등을 통하여 수술 방법을 선택하였으며 과두부 골절이 아닌 경우 대개 골절 부위의 견고 고정 및 근심쪽 과두 골편 제거, 관절 성형술 및 관절원판 정복술, lag screw고정 등을 시행하였다. 술 후 악간 고정은 약 2주 정도 하였으며 이후 수동적 개구 운동 및 능동적 개구 운동을 2에서 4주, 4주이상에서 시행하였다. 술후 방사선학적 관찰시 과두 흡수 및 후방 부위로 근심 과두부 변위 등, 약 21.5%에서 술 후 방사선학적 변화를 가져왔으며 특히 Dr. 남씨법에서 더 많이 나타났다(Dr. 남씨법(32%), 다른 정복술(16%)). 술 후 임상 증상은 19%의 일시적 안면신경 마비, 개구시 하악 변위(16.4%), 악관절 동통(15.2%), 35mm 이하에서의 개구제한(10%), 기타 부정교합, 관절잡음, 가성 관절 강직 등의 합병증을 나타냈으며 이중 Dr. 남씨법에서 더 많은 합병증을 나타냈다. 과두 골절의 와괴적 처치는 가능한 견고 고정을 시행하는 것이 좋으며 이중 Dr. 남씨법은 그 사용에 있어 고려 해 보는 것이 좋다고 사료된다. 특히 과두 골절 처치에 있어 무엇보다도 술 후 계속적인 환자 관리 및 장기간 예후 관찰이 필수적이라 사료된다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제11권1호
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• pp.130-152
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• 1989

The purpose of this study was to observe the effect of intermaxillary fixation on the chondrocytes of the mandibular condyle under the light and the electron microscope. For this study, twenty rabbits were placed in maxillomandibular fixation, and two were used as a control group. The experimental group was subdivided into 3, 7, 14, 21 and 28 day group. After the experimental period of 3, 7, 14, 21 and 28 days, the animals were sacrificed with a vascular perfusion of 2.5% glutaraldehyde. The condylar processes were exenterated, and decalcified in 0.1M EDTA with 2.5% glutaraldehyde solution for two weeks. The specimens were rinsed with phosphate buffer solution and the post-fixation was carried out with 2% osmium tetroxide at $4^{\circ}C$ for two hours. Thereafter the specimens were dehydrated in alcohol series, cleared with propylene oxide and embedded in Epon 812 resin. Thin sections and ultra-thin sections were made, and the cellular structures of the condylar cartilages were observed with light and electron microscope. The results were as follows: 1. In the intermaxillary fixation group, the cartilaginous tissues of mandibular condyles showed a marked decrease in the thickness compared to the control group. 2. A remarkable change was noticed in the proliferating and the hypertrophic zone of the condylar cartilages in the experimental group. 3. An atrophic change of the condylar cartilage was appeared in the 3 day experimental group and degenerative change was observed in the 7 day experimental group, and recovery was seen in thereafter 14 day experimental group. 4. Calcification, degeneration and resorption of condylar cartilage were recognizable, and the cellular zone of the condylar cartilage was appeared indistinctly in 3 day and 7 day experimental group. The chondroblasts, however, were differentiated into chondrocytes and resumed mitosis, and then the cellular zones of the condylar cartilage were reorganized from the 14 day experimental group under the findings of light microscope. 5. Under the findings of electron microscope, atrophic changes and decrease in number of intracellular organelles, degenerative changes of cytoplasm, and pyknosis of nuclei were observed in early stage, however, a gradual regeneration and reorganization of the intracellular organelles were observed from 14 day experimental group.

• Journal of Oral Medicine and Pain
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• 제35권1호
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• pp.61-73
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• 2010

2006년 한 해 동안 경북대학교 구강내과에 내원한 하악과두의 형태적 변이가 관찰된 10대 과두흡수 환자를 대상으로 임상검사와 악안면 골격형태를 분석하여 다음과 같은 결론을 얻었다. 1. 임상적 평가 1) 10대 과두흡수 환자는 59명으로 여자는 47명, 남자는 12명으로 여자에서 월등히 많이 유발되었다. 환자의 연령분포는 12세가 2명, 14세가 9명, 15세가 4명, 16세가 8명, 17세가 12명, 18세가 12명, 그리고 19세가 12명으로 나타났다. 2) 과두의 편평화나 침식, 과두형태의 변형이 초래된 Grade II를 많이 나타냈다. 3) Class I 교합자가 27명으로 가장 많았고, 개교합이 동반된 경우는 20명, 평균 overjet은 3.58mm, overbite는 0.97mm를 보였다. 4) 과두흡수 부위의 통증을 호소한 경우는 41명, 통증을 호소하지 않은 경우가 18명이었다. 5) 이갈이 습관을 26명, 이악물기 습관은 24명이 보고하였다. 6) 환자의 치료기간은 1개월 미만이 23명, 보조요법으로 치료한 경우가 28명이었다. 2. 악안면 골격 형태 평가 1) 16세 여자환자에서 SNA, SNB는 유의한 작은 값을 나타냈고 articular angle은 유의한 큰 값을 보였다. 2) 17세 여자환자에서 SN, SAr, TPFH와 ramus height가 유의한 작은 값을, SN-GoMe, FMA 그리고 articular angle은 유의한 큰 값을 나타냈다. 3) 18세 이상 여자 환자에서는 SN, SNB, TPFH, ramus height은 유의한 작은 값을, ANB, FMA, SN-GoMe, LAFH, articular angle, gonial angle은 유의성 있는 큰 값을 보였다. 4) 18세 이상 남자 환자에서는 SN, TPFH, ramus height은 유의한 작은 값을 FMA, SN-GoMe, LAFH, articular angle, gonial angle은 유의성 있는 큰 값을 보였다. 5) mandibular body length는 10대 과두흡수 환자에서 정상인과 차이가 없었다. 10대 과두흡수의 특징은 임상적으로 통증호소는 심하지 않으나 골소실이 빠르게 일어나서 이환측 과두에서 후방지지의 갑작스런 상실이 초래되는 특발성 과두흡수의 형태를 많이 나타내며 개교합 발생 비율도 높았다. 근골격계 성장이 완료되지 않은 10대에 특히 수직적 악안면 골격형태로 인한 부하의 집중과 이상기능활동에 의해 하악과두에 과도한 부하가 가해지면 과두흡수가 더욱 쉽게 일어날 수 있으며, 결국 악골의 성장을 저해하고 안모에 악영향을 미칠 수 있을 것으로 생각한다.