• 대한심미치과학회지
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• 제10권1호
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• pp.8-15
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• 2001

The Class III malocclusion classified in two types of Skeletal Class III and Pseudo Class III. In the case of the maxillary deficiency, the protraction H-G(facemask) with Bonded RPE can be used. For children with A-P and vertical maxillary deficiency, the preferred treatment is to move the maxilla into a more anterior and inferior position, which also increases its size as bone is added at the posterior and superior sutures. Successful forward repositioning of the maxilla can be accomplished before age 8. To resist tooth movement as much as possible, the maxillary teeth should be splinted together as a single unit. The maxillary appliance must have hooks for attachment to the facemask that are located in the canine-primary molar area above the occlusal plane. The facemask usually worn until a positive overjet of 2-5mm is achieved interincisally. Occipital chin cup is successful in those patients who can bring their incisors close to an edge-to-edge position when in centric relation. This treatment is particularly useful in patients who begin treatment with a short lower anterior facial height, as this type of treatment can lead to an increase in lower anterior facial height. If the pull of the chin cup is directed below the condyle, the force of the appliance may lead to a downward and backward rotation of the mandible.

• 대한치과교정학회지
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• 제19권1호
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• pp.153-167
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• 1989

This study was undertaken to analyze the growth of mandible in surgically repaired unilateral cleft lip and palate. The subjects consisted of 63 unilateral cleft lip and palate individuals, 60 class III malocclusions and 60 normal occlusions ranging from 6 to 15 years old. Each group was divided into two age groups. (6-10 Y and 11-15 Y) The results obtained from UCLP compared with other groups were as follows: 1. The anteroposterior position of the chin was similar to that of the normal occlusions. 2. The shape of the mandible was similar to that of the class III malocclusions. 3. In mandibular size, ramus height was the smallest among three groups, but body length and overall mandibular length were similar to those of the normal occlusions. 4. The lower border of the mandible was the steepest among three groups and strong vertical or clockwise growth tendency was indicated. 5. The position of condyle in relation to the cranial base showed little difference in three groups. 6. In older age group , vertical growth tendency of the mandible decreased more or less.

• 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 Oral Medicine and Pain
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• 제39권4호
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• pp.152-155
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• 2014

Temporomandibular joint (TMJ) dislocation is defined that the disc-condyle complex is positioned anterior to the articular eminence in the open mouth position, and is unable to return to a normal closed mouth position without a manipulative maneuver. TMJ dislocation can recur habitually and result several problems to patients such as discomfort, pain, fear, and anxiety. The only definitive treatment for TMJ dislocation is surgical alteration of the joint itself. In most cases, however, a surgical procedure is far too aggressive for the symptoms experienced by the patient. In addition, the effect of surgical treatment may be insufficient, and the recurrence have been reported. It is also possible to develop several complications after surgical treatment. Therefore much effort should be directed at supportive therapy in an attempt to eliminate the disorder or at least reduce the symptom to tolerable levels. Through this cases the authors present favorable treatment outcome using occlusal splint with the patient of TMJ dislocation. Occlusal splint therapy can be considered as easy, safe, and useful non-invasive modality to treatment of TMJ dislocation.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제13권1호
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• pp.95-99
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• 1991

악안면 기형에 대한 활발한 치료가 행해지고 있는 가운데 악교정술 후에 발생하는 회귀현상(Relapse)에 대해서는 아직도 많은 연구가 진행되고 있다. 특히 하악골 전돌증으로 후방이동술을 시술받은 환자의 경우에 회귀의 원인으로 Schendel, Epker, Lake, Worms, Ive, Poulton과 Ware등 많은 학자들이 하악과두의 부적합한 위치를 강조하였다. 하악골 시상골절단술시에는 이미 Leonard(1976), Zecha 등 (1978)이 상악의 선부자에 acrylic과 wire 또는 retainer 등을 이용하여 하악근심 골편의 보존을 시도하였다. 이에 저자는 하악골 전돌증의 후방 이동량이 큰 경우나 심한 안면 기형이 있는 19명의 환자에 대해 하악지 수직골절단술을 시술한 경우에 주로 정형외과에서 사용하는 External Skeletal Pin Fixation인 Mini-Hoffmann Sets을 이용하여 하악과두의 중심교합위 보존에 도움을 주었기에 보고하는 바이다.

• 대한치과의사협회지
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• 제56권3호
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• pp.134-141
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• 2018

Purpose: To measure the head tilting angle creating initial condylar cut-off and to find the head position inducing the superimposition of the cervical vertebrae over the mandibular ramus on panoramic radiograph. Materials and Methods: The panoramic radiographs were taken with Didactic skull on cervical spine model (Scientific GmbH, Hamburg, Germany) using Kodak 8000c Digital Panoramic radiography. For the inherent radiolucency of the plastic skull model, radiopaque 1 mm diameter lead wires were attached along the margin of the mandibular condyle, ramus, mandibular body, cervical vertebrae, and FH plane of the skull model. For measuring the head tilting angle creating the condylar head cutoff, panoramic radiographs were taken by tilting the FH plane downward in 5 degree increments. For finding the distance between transverse process of the third cervical vertebra and gonion inducing superimposition of cervical vertebrae on the mandibular ramus, panoramic radiographs were taken by decreasing the distance in 0.5 cm increments. Result and Conclusion: The condylar cutoff began to appear when the head of skull model was tilted downward by 15o. As the head tilting angle increasing, the condylar cutoff became more prominent. The superimposition of cervical vertebrae over the mandibular ramus began to appear when the distance between the gonion and third cervical vertebra was 1.0 cm. As the distance decreasing, the superimpostion became more prominent.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제12권2호
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• pp.9-20
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• 1990

A series of 19 cases with maxillary hyperplasia and mandibular retrognathia were operated on by simultaneous superior repositioning of the maxilla after Le Fort I osteotomy and anterior repositioning of the mandible after bilateral sagittal split ramus osteotomies with or without osteotomy of the inferior border of the mandible. These were evaluated by retrospective cephalometric and computer analysis for the longitudinal skeletal and dental changes for an average of 17.1 months after surgery. For stabilization of the osteotomized segments, the authors used wire osteosynthesis by means of bilateral infraorbital and zygomatic buttress suspension wire at the maxilla, and direct interosseous wire at the split segments of the mandibular rami. Results show generally good stability after simultaneous maxillary and mandibular surgery with wire osteosynthesis, and a minimal to moderate tendency toward skeletal and dental relapse. This article is a preliminary study to defy the efficiency of the wire osteosynthesis (wo)compared with rigid internal fixation (RIF) for simultaneous maxillary and mandibular surgery. 1. The vertical relapse rate of the A point after superior repositioning of the maxilla is 2.2%. 2. The horizontal relapse rate of the B point after advancement of the mandible is 18.3%. 3. The condyle is distracted inferiorly and slightly posteriorly at the immediate postoperative period. 4. At the long term follow up examination, the condyle presents tendency of return to the preoperative position. 5. Condylar segment angle is decreased at the immediate postoperative period, and at the long term follow up evaluation, the angle is increased. 6. Gonial angle is increased at the immediate postoperative period, and then is decreased at the long term follow up evaluation. 7. The dentition is satisfactory with acceptable movement at the long term follow up evaluation. 8. At the mandibular free body analysis, genioplasty shows good stability. 9. Wire osteosynthesis provides excellent stabilization for the simultaneous maxillary and mandibular surgery.

• Imaging Science in Dentistry
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• 제46권2호
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• pp.127-131
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• 2016

Purpose: This study was performed to compare the condylar position in patients with temporomandibular joint disorders (TMDs) and a normal group by using cone-beam computed tomography (CBCT). Materials and Methods: In the TMD group, 25 patients (5 men and 20 women) were randomly selected among the ones suffering from TMD according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). The control group consisted of 25 patients (8 men and 17 women) with normal temporomandibular joints (TMJs) who were referred to the radiology department in order to undergo CBCT scanning for implant treatment in the posterior maxilla. Linear measurements from the superior, anterior, and posterior joint spaces between the condyle and glenoid fossa were made through defined landmarks in the sagittal view. The inclination of articular eminence was also determined. Results: The mean anterior joint space was 2.3 mm in the normal group and 2.8 mm in the TMD group, respectively. The results showed that there was a significant correlation between the superior and posterior joint spaces in both the normal and TMD groups, but it was only in the TMD group that the correlation coefficient among the dimensions of anterior and superior spaces was significant. There was a significant correlation between the inclination of articular eminence and the size of the superior and posterior spaces in the normal group. Conclusion: The average dimension of the anterior joint space was different between the two groups. CBCT could be considered a useful diagnostic imaging modality for TMD patients.

• 대한구순구개열학회지
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• 제5권1호
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• pp.27-42
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• 2002

This study was designed to evaluate the morphology and the position of the mandible in the complete unilateral cleft lip and palate patients, Craniofacial skeletal morphology pattern was analyzed on the lateral cephalometric radiographs of the 50 subjects of complete unilateral cleft lip and palate, the 50 normal and 50 class III, Each group was divided into child and adult sub-groups, All the data were tested statistically. The results were as follows: I, In the comparison with the normal group, complete cleft group showed smaller angular, condylar length, clockwisely rotated mandible and larger NMe/SGo(p<0.01). 2, In the comparison with the class III group, the complete cleft group showed significantly smaller angular, condylar, ramal, body length of the mandible(p<0,01). 3. As for the position of the mandibular condyle to the cranial base, the class III group was the most anterior, the normal group was the most posterior and the complete cleft group was in the middle(p<0.05). 4. In the comparison with child group, the normal adult group showed smaller mandibular angle and mandibular plane angle, but not the other two groups. And the complete cleft group and the class III group showed the similar change. The normal and class III group showed increased XiCd/XiPog, but not the complete cleft group(p<0.01).

• Journal of Periodontal and Implant Science
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• 제46권2호
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• pp.96-106
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• 2016

Purpose: Stress distribution and mandible distortion during lateral movements are known to be closely linked to bruxism, dental implant placement, and temporomandibular joint disorder. The present study was performed to determine stress distribution and distortion patterns of the mandible during lateral movements in Class I, II, and III relationships. Methods: Five Korean volunteers (one normal, two Class II, and two Class III occlusion cases) were selected. Finite element (FE) modeling was performed using information from cone-beam computed tomographic (CBCT) scans of the subjects' skulls, scanned images of dental casts, and incisor movement captured by an optical motion-capture system. Results: In the Class I and II cases, maximum stress load occurred at the condyle of the balancing side, but, in the Class III cases, the maximum stress was loaded on the condyle of the working side. Maximum distortion was observed on the menton at the midline in every case, regardless of loading force. The distortion was greatest in Class III cases and smallest in Class II cases. Conclusions: The stress distribution along and accompanying distortion of a mandible seems to be affected by the anteroposterior position of the mandible. Additionally, 3-D modeling of the craniofacial skeleton using CBCT and an optical laser scanner and reproduction of mandibular movement by way of the optical motion-capture technique used in this study are reliable techniques for investigating the masticatory system.