• 대한치과보철학회지
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• 제30권2호
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• pp.286-318
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• 1992

The objective of preventive dentistry is the maintenance of a healthy dentition for the life of a patient. Unfortunately, if an individual has not received the benefit of a comprehensive program of preventive dentistry and has finally reached the edentulous state, as a consequence, he receives a set of complete denture. Dentures are mechanical devices and subject to the principles of mechanics. In some cases, the general health and nutritional status of the patient are felt to be the causative factors. But, the most important thing in residual ridge resorption is felt to be caused by the unequal distribution of functional forces. This study was to analyze mandibular stresses of complete denture occlusion by three dimensional finite element method. The results were as follows ; 1. As deformation and stress distribution of the complete denture of the mandible were concentrated on the upper lingual side of the mandible, alveolar ridge resorption of the mandible occurred from lingual side to labio-buccal side. 2. Analyzing by three dimensional F. E. M., the mandible is a very effective form for tolerating stress and deformation biomechanically. 3. According to the concentration of stress distibution in the upper buccal side of the lower posteriors, buccal shelf area must be a primary stress bearing area in the lower complete denture. 4. Lower complete denture moved horizontally to the balancing side under lateral occlusal force. 5. Bilateral balanced occlusion should be constructed in the complete denture for denture stability, especially in the protrusive movement. 6. Physical property of the denture base material was as important for stress distribution in the denture base as or even more than that in the mandible. 7. Impression technique is very important because of most of stress was concentrated between them due to close contact of the mandible and the denture base.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제11권1호
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• pp.93-100
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• 1989

This is a report of comparison of condyle fracture treatment by functional treatment and surgical treatment. In cases of functional therapy, mode of action of Activator that we used; By fulcrum of posterior teeth, the mandibular elevators of the opposite side cause the gap in the dental arches to be reduced, while the mandible performs a rotational movement about the fulcrum during which the fracture surface of the large fragment moves downward. Condylar fractures are often seen in association with fractures of other regions of the mandible. In our department, such cases were treated by miniplate and intramaxillary fixation. Surgical treatment of fractures of the mandible condylar were treated by intraoral approach. The result were drawn as follows : 1. Lateral displacement of condyle ; functional therapy with activator. 2. Compound fracture ; miniplate osteosynthesis and physiotherapy. 3. Anteriormedially displacement ; surgical treatment.

• Journal of Oral Medicine and Pain
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• 제13권1호
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• pp.5-12
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• 1988

The purpose of this study was to evaluate the therapeutic effect of occlusal stabilization splint on the clinical symptoms and the condylar movement in patients with Temporomandibular Disorders(TMD). For the study, 15 TMD patients treated with stabilization splint and followed up were selected. The age of them was from 18 to 65 years and the mean period of treatment was 2.9 months. The author examined signs and symptoms of TMD according to Dr. Friction's evaluation from and recorded the condylar paths with Denar pantronic before and after splint therapy. The obtained results were as follows : 1. On the first visit, 11 patients(73.3%) showed muscle tenderness on palpation and the frequency was lateral pterygoid, masseter, medial pterygoid, temporalis, sternocleidomastoideus in the order named. 2. Occlusal stabilization splint was more effective in pain relief(100%) than in other dysfunction improvement(85.7%) 3. The amount of maximum opening increased from 37.1㎜ to 42.2㎜, but those of protrusion and laterotrusion changed little. 4. Pan. PRI scores decreased from 32.9 to 21.8, which meant improved reproducibility of mandibular border movements, and the group with sever dysfunction category showed more decrease in score than the group with moderate or slight dysfunction category.

• 대한치과보철학회지
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• 제26권1호
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• pp.113-131
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• 1988

Although TMJ sound is common, its relationship to subjective and objective evaluation and the magnitude and the position of the sound during the mandibular movement is not fully understood. So, the purpose of this investigation was to provide further insight into the characteristics of the TMJ sounds. Twelve subjects (9 men and 3 women) with TMJ sounds were selected from students at Chosun University, School of Dentistry. Condylar movements and TMJ sounds of each subject were recorded and analyzed using a simplified condylar path recorder and a sound checker. Although specific conclusions were difficult to make from this study, the finding suggested the followings. 1. The position of TMJ sounds were visually observed and marked on the condylar tracings during maximum opening and closing, protrusive and retrusive and right and left lateral movements. 2. Information about the size, location and number of condylar deviations and the translation freedom of the condyle was recorded and analyzed objectively. 3. The most obvious characteristic of TMJ sounds was their variability. 4. TMJ sounds were categorized into one of four groups (soft click, hard click, soft crepitus, hard crepitus) by the quality and quantity of the duration and amplitude components.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제26권4호
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• pp.383-390
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• 2000

The purpose of this study was to compare the soft tissue movements in facial profile predicted by a computer package with those that had actually accured following a sagittal split ramal osteotomy. The reliability of predicting the results of orthodontic surgical treatment was analysed. The study was based on the serial records of 30 consecutive patients who had been treated by means of a sagittal split ramal osteotomy. The serial lateral cephalometric radiographs used for the study were taken at the following stages: immediate preoperative : immediate postoperative : 6 months postoperative. A superimposition T1, T2-3 was generated to allow visual comparision. The results can be considered in relation to four important parts of the facial profile :the nose, upper lip, lower lip, and chin. The nose & Upper lip:The amount of movement of the upper lipwas not badly predicted for the average case. The lower lip: There was a significant trend over the whole sample for vertical positionof the lower lip to be less well predicted. The chin: The soft tissue movements of the chin were well predicted.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제32권6호
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• pp.559-565
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• 2006

The aim of this study was to evaluate the amount and interrelationship of the soft and hard tissue changes after simultaneous maxillary clockwise rotation and mandibular setback surgery in skeletal class III malocclusion. The sample comprised of 16 adult patients who had anteroposterior skeletal discrepancy. These patients had received presurgical orthodontic treatment and surgical treatment which consisted of Le fort I Osteotomy and bilateral saggital split ramus osteotomy. The presurgical (T1) and postsurgical (T2) lateral cephalograms were evaluated. The computerized statistical analysis was carried out with SPSS/PC program. The results demonstrated a decrease in the vertical dimension in the soft and hard tissue. The nasolabial angle was increased and the mentolabial angle was decreased. The results showed also many statistically significant correlations(p<0.05). The lower lip closely followed the skeletal movement of the B- point in the horizontal plane. The double jaw rotation surgery can afford a good solution to solve the problems of class III malocclusion cases.

• Journal of Oral Medicine and Pain
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• 제7권1호
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• pp.47-58
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• 1982

The author has studied on the clinical features and symptomatology of 97 MPDS patients, who visited the Dept. of Dentistry, Kyungpook National University, from January to September in 1982. The results were as follow : In age and sex distribution of patients in this population, the third decades appeared to have the highest prevalence and the male to female ratio was almost 1 to 2.23. As to occupation, students and housewives were revealed to have the highest incidence of MPDS. The chief complaints of patients were pains, TMJ noises, and limitation of mouth opening in order of frequency, and the most prevalent site of symptom was that of preauricular area. In symptom sequence, the majority of initial symptoms were TMJ noise and pain but limitation of mandibular movement was progressively developed, regardless of nature of early symptoms. Chronic unfavorable oral habits were found to be the most possible predisposing factors in this study. The average maximum interincisal distance was $38.13\pm10.00mm$ in males and $30.73\pm8.75mm$ in females, and a deviation of mandible during mouth opening was observed in 60.8% of patients. In TMJ signs, tenderness of the TMJ to palpation was found in 60.8% of patients and TMJ noise was audible in 50.5% of patients with a stethoscope. The muscles of masticatory system were palpated according to usual methods, and a significant indidence of muscular tenderness was present, with the lateral pteygoid muscles being most frequently involved, followed by masseter, medical pterygoid and temporalis muscles.

• Journal of Oral Medicine and Pain
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• 제7권1호
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• pp.86-94
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• 1982

Maximal active movements of the mandible in the vertical and the horizontal plane were measured in 147 boys and 155 girls. with an age of 13, 15, 17 years respectively. The studied persons had no pain or severe symptoms of dysfunction of the masticatory system and the method used in this paper was devised by Agerberg, and the numerical calculations were performed at the Dept. of Medical Engineering of Seoul National University Hospital. The obtained results were as follows : 1. The mean values of maximal opening in 13 year-old boys and girls were 58.5 mm,58.9 mm respectively, and the mean values of boys were increased with age. 2. The mean values of maximal lateral movement to the right in 13-year-old boys and girls were 9.1 mm, 8.3 mm respectively, and the mean values to the left were 9.3 mm, 8.7 mm resprctively. The mean values were not increased with age in both. 3. The mean values of maximal protrusion in 13-year-old boys and girls were 8.7 mm, 8.1 mm respectivly, and in all ages the mean values of boys were larger than those of girls. 4. The range of maximal mandibular movements in teen-agers with 95% probability prediction ellipses were presented.

• 대한치과교정학회지
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• 제32권6호
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• pp.413-424
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• 2002

성장기 아동에서 상악골 열성장을 보이는 제III급 부정교합은 상악골 전방 견인 장치의 적응증이 된다. 상악골 전방 견인장치의 바람직한 효과는 상악골의 전방 이동이지만, 실제로는 상악 치아의 전방 이동, 하악골의 후하방 회전, 하악 전치의 설측 이동 등의 복합적인 결과로 III급 관계가 개선된다고 알려져 있다. 그러나 수직적 안모 유형별로는 상악골 전방 견인 장치의 효과에 대한 차이는 잘 알려진 바가 없다 본 연구는 1998년-2000년 사이에 연세대학교 치과병원 교정과에 내원한 환자들 중 초진시 나이는 6세 6개월에서 13세 3개월 사이의 상악골 열성장을 동반한 제 III급 부정교합으로 진단된 67명 (남 36, 여 31)을 대상으로, 안모유형별로 SNMP군과 Gonial angle군에서 low, average, high로 세부군을 나누어 치료전 측모 두부방사선 규격사진을 통해 상악골 전방견인 장치의 효과를 비교하여 다음과 같은 결과를 얻었다. 1) SNMP군의 low angle에서 B point의 후방이동량이 많았으며, High angle에서는 A point의 전방이동량이 컸다. 2) Genial angle군의 low angle에서 A point의 전방이동양이 가장 적었으며, high angle에서는 A point의 전방이동량이 상대적으로 많았다. 3) A point에 대한 arcTan를 구한 결과 A point의 이동 각도는 장안모 군에서 더 수평적인 이동 양상을 보였고, 단안모 군에서는 수직적 이동양상이 강했다. 4) SNMP군과 Gonial angle의 세부군에서 치료기간별 유의성은 없었다.

• Imaging Science in Dentistry
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• 제45권1호
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• pp.1-5
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• 2015

Purpose: Lateral pterygoid muscle (LPM) plays an important role in jaw movement and has been implicated in Temporomandibular disorders (TMDs). Migraine has been described as a common symptom in patients with TMDs and may be related to muscle hyperactivity. This study aimed to compare LPM volume in individuals with and without migraine, using segmentation of the LPM in magnetic resonance (MR) imaging of the TMJ. Materials and Methods: Twenty patients with migraine and 20 volunteers without migraine underwent a clinical examination of the TMJ, according to the Research Diagnostic Criteria for TMDs. MR imaging was performed and the LPM was segmented using the ITK-SNAP 1.4.1 software, which calculates the volume of each segmented structure in voxels per cubic millimeter. The chi-squared test and the Fisher's exact test were used to relate the TMD variables obtained from the MR images and clinical examinations to the presence of migraine. Logistic binary regression was used to determine the importance of each factor for predicting the presence of a migraine headache. Results: Patients with TMDs and migraine tended to have hypertrophy of the LPM (58.7%). In addition, abnormal mandibular movements (61.2%) and disc displacement (70.0%) were found to be the most common signs in patients with TMDs and migraine. Conclusion: In patients with TMDs and simultaneous migraine, the LPM tends to be hypertrophic. LPM segmentation on MR imaging may be an alternative method to study this muscle in such patients because the hypertrophic LPM is not always palpable.