• Journal of Oral Medicine and Pain
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• 제2권1호
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• pp.8-16
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• 1974

The author performed electromyographic analysis on edentulous patients aging 52 to 77 who have upper and lower full dentures for 3 to 7 years of duration. And the graphs were recorded in physiologic rest position, incisal occlusion, molar occlusion, left lateral excursion, right lateral excursion and mandibular projection. The results obtained are as follows : 1. 80 per cent of the patients are in unilateral mastication. 2. The shorter history of edentulous mouth reveals the more electric potency. 3. Facial deviation owing to unilateral mastication is the cause of higher electric potency to the deviated site. 4. There were no difference in electric potency between mandibular projection and incisal occlusion.

• 대한소아치과학회지
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• 제48권1호
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• pp.64-76
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• 2021

이 연구의 목적은 CBCT를 이용해 소아에서 연령에 따른 하악공과 하악소설의 위치 및 하악소설의 형태를 평가하고, 하치조신경 전달마취 시 고려할 수 있는 자입점을 제시하는 것이다. 과잉치 발거 또는 매복치 평가를 위해 CBCT를 촬영한 만 6 - 16세의 영상을 수집하였다. 연령에 따라 만 6 - 7세, 10 - 11세, 15 - 16세의 3군으로 분류하였으며 군당 남녀 각 30명씩을 포함하여 총 180명의 하악지 좌우가 분석되었다. 좌우 측의 하악소설로부터 하악지의 전연, 후연, 상연, 하연까지의 최단거리를 계측하고 하악소설과 하악공 사이의 최단거리, 교합평면에 대한 하악소설과 하악공 사이의 수직거리를 각각 측정하였다. 하악소설의 형태를 기준에 따라 4가지 형태로 분류하여 평가하였다. 하악지의 전후방 및 수직적 기준점으로부터 하악소설의 위치는 연령에 따라 모든 방향으로 증가하는 양상을 보였으며 하악소설과 하악공 사이의 거리 역시 연령에 따라 증가하는 양상을 보였다. 교합평면에 대한 하악소설 및 하악공의 거리는 연령에 따라 상방으로 이동하는 양상을 보였다. 하악소설의 형태는 삼각형 형태가 가장 많았고 결절형, 절두형, 동화형 순이었으며 연령에 따른 차이는 보이지 않았다. 연구를 통해 수평적인 마취의 자입점은 하악지의 전연으로부터 연령에 따라 각각 17 mm, 18 mm, 19 mm로 증가된 지점이 권장되며, 수직적인 마취의 자입점은 연령에 따라 교합평면 상방 2 - 3 mm, 5 - 6 mm, 9 - 10 mm로 자입점을 높이는 것이 권장된다.

• 대한치과교정학회지
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• 제28권4호
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• pp.487-498
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• 1998

이 연구는 하악전돌증의 하악후퇴수술후에 기도의 크기변화, 혀의 공간적 위치 및 형태변화,설골의 위치변화를 계측하여 이들의 순응양상을 관찰하기 위하여 시행되었다. 하악전돌증의 하악후퇴수술후 최소 6개월이상의 추적관찰기간중 임상적으로 양호한 수술결과를 보이는 37명을 대상으로 촬영한 수술직전, 수술직후 및 최소 6개월이상의 추적기간경과후에 촬영된 측모 두부 엑스선 규격사진을 연구자료로 하여 계측, 통계처리 및 분석을 통하여 다음의 결론을 얻었다. 1. 비인두부와 후두인두부의 기도크기는 수술에 의한 변화가 없었으나, 구강인두부의 기도크기는 수술직후 경미한 감소를 보였고, 추적조사기간중에 감소상태로 순응하였다. 2. 두개저에 대한 설골의 위치는 수술직후 후하방이동하였고, 추적조사기간동안에 복귀되는 양상을 보였으나, 수술전에 비해 후하방이동된 위치에서 순응하였다. 설골에서 이극까지의 거리는 수술직후 감소하고, 추적조사기간중에도 계속 감소하는 순응양태를 보였다. 3. 두개저에 대한 혀의 위치는 혀의 배면이 수술직후 하방으로 이동하였다가, 추적조사기간중에 상방이동하여 원래의 위치에서 순응하였고, 수술직후 후퇴하여 그 위치에서 순응하였다. 혀의 후상방부는 수술직후 변화 없다가 추적조사기간에 상방으로 이동하여 순응하였고, 수술직후의 추적조사기간에 전후방적변화가 없었다. 설근부는 수술직후 에 후하방으로 이동하여 추적조사기간중 그 위치에서 순응하였다. 4. 혀의 형태변화는 설골에서 설배면까지의 거리가 수술직후 증가하였다가, 추적 조사기간에 감소하였으나, 수술전에 비하여 증가하였고, 설골에서 혀의 후상방부 및 설근부까지의 거리는 수술후 증가되어 추적조사기간중에 유지되었다. 5. 수술에 의한 하악골의 후방이동량은 기도, 혀 및 설골의 위치변화량 및 크기변화량과 전반적으로 상관성을 보이지 않았다.

• 대한치과교정학회지
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• 제21권3호
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• pp.591-601
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• 1991

To determine the difference in cephalometric measurements between centric relation and centric occlusion, 60 patient-20 patients for each malocclusion group-were examined with the cephalograms in centric relation and in centric occlusion. The results are as follows: 1. There are differences in cephalometric measurements with the mandible in the two different position, and some measurements are statistically significant. 2. No clinically useful prediction may be made from cephalometric radiographs concerning the amount of mandibular deflection from centric relation to centric occlusion. 3. If, the large differences in the cephalometric measurements with the mandible in the two different position, the analysis with the cephalogram in centric occlusion is needed to be compensated with the other clinical approach.

• Restorative Dentistry and Endodontics
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• 제5권1호
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• pp.35-40
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• 1979

The author observed thy actual position of apical foramen and the radiographic appearance of files when the files were filled through canals to the external surface of apical foramen in 280 canals of extracted teeth. All the teeth were radiographed by bisecting technic and once again Walton's projection was employed on mandibular molars. The results were as followings. 1. Sixty five percents of 280 canals were actually classed as having foramina deviant from true apex of root. 2. 160 of 280 canals(Fifty seven percents) appeared to be filled short of apex on the radiograph. 3. When Walton's projection was employed to open up two mesial canals of mandibular molars and compared to straight-on projection, twelve of 120 canals Ten percent appeared to be different in radiographic appearence.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제35권6호
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• pp.420-425
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• 2009

Purpose: The aim of this study is to analyze the correlation between incidence of mandibular angle fracture and eruption state of mandibular third molar using clinical and radiographic findings. Materials and Methods: The data were obtained from the clinical and radiographic records of 205 patients who visited the Department of Oral and Maxillofacial Surgery, Chonbuk National University Hospital for treatment of the mandibular fracture. Panoramic radiographies were taken for radiographic examination and the mandibular third molars were classified according to age, gender, position and eruption state. Data were analyzed by a chi-square statistics. Results: In this study, the incidence of mandibular angle fracture had a tendency to be greater when a mandibular third molar was present(p>0.05), but there was not a statistically significant difference. Of the 255 cases with a mandibular third molar, 67 had an angle fractures. Of the 155 cases without a mandibular third molar, 138 had not angle fracture. And the incidence of mandibular angle fracture was high at class BII(by Pell & Gregory system)(p<0.05). Conclusion: Although there was not a statistically significant difference, mandibular third molar was more susceptible to mandibular angle fracture. When the reduction of mandibular angle fracture, it was recommended that mandibular third molar should be extracted especially in case of pericoronitis, periodontitis and other infections.

• 대한치과교정학회지
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• 제22권4호
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• pp.837-853
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• 1992

The purpose of this study was to investigate the positional changes of the mandibular condyles after orthognathic surgery In patients with severe skeletal Class III malocclusion. This study was based on 21 patients who had received bilateral sagittal split osteotomy for mandibular setback. Among them 14 were fixated non - rigidly (W group), and 7 were fixated rigidly (R group). After submental vertex view analysis, each subject was given the T.M.J. Tomogram in both centric occlusion and centric relation immediate before, $4\~6$ weeks after and more than 6 months after surgery. The anteroposterior and vertical changes between each time interval were measured and analyzed statistically. Following results were obtained. 1. There was no significant difference between right and left condyles in their anteroposterior and vertical changes of the condylar position. 2. In anteroposterior changes of condylar position of the wire fixation group, the condyles were moved anteriorly 4-6 weeks after surgery, and then the pattern of reestablishment to their preoperative position was observed more than 6 months after surgery. In the rigid fixation group, there was no significant difference in any observation periods of centric occlusion and centric relation. 3. In vertical changes of condylar position of the wire fixation group. the condyles were moved inferiorly 4-6 weeks after surgery, and then the pattern of reestablishment to their preoperative position was observed more than 6 months after surgery. In the rigid fixation group, the condyles were moved inferiorly 4-6 weeks after surgery, and then the pattern of reestablishment to their preoperative position was observed more than 6 months after surgery in centric occlusion only.

• 대한치과교정학회지
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• 제52권1호
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• pp.53-65
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• 2022

Objective: Planning of incisal position is crucial for optimal orthodontic treatment outcomes due to its consequences on facial esthetics and occlusion. A systematic summary of the proposed parameters is presented. Methods: Studies on Google Scholar^©, PubMed^©, and Cochrane Library, providing quantitative information on optimal central incisor position were included. Results: Upper incisors supero-inferior position (4-5 mm to upper lip, 67-73 mm to axial plane through pupils), antero-posterior position (3-4 mm to Nasion-A, 3-6 mm to A-Pogonion, 9-12 mm to true vertical line, 5 mm to A-projection, 9-10 mm to coronal plane through pupils), bucco-lingual angulation (4-7° to occlusal plane perpendicular on models, 20-22° to Nasion-A, 57-58° to upper occlusal plane, 16-20° to coronal plane through pupils, 108-110° to anterior-posterior nasal spine), mesio-distal angulation (5° to occlusal plane perpendicular on models). Lower incisors supero-inferior position (41-48 mm to soft-tissue mandibular plane), antero-posterior position (3-4 mm to Nasion-B, 1-3 mm to A-Pogonion, 12-15 mm to true vertical line, 6-8 mm to coronal plane through pupils), bucco-lingual angulation (1-4° to occlusal plane perpendicular on models, 87-94° to mandibular plane, 68° to Frankfurt plane, 22-25° to Nasion-B, 105° to occlusal plane, 64° to lower occlusal plane, 21° to A-Pogonion), mesio-distal angulation (2° to occlusal plane perpendicular on models). Conclusions: Although these findings can provide clinical guideline, they derive from heterogeneous studies in terms of subject characteristics and reference methods. Therefore, the optimal incisal position remains debatable.

• 대한치과보철학회지
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• 제32권3호
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• pp.396-410
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• 1994

Ten subjects who were going to wear conventional complete dentures were selected for this study. Theree subjects were women and seven were men. The average age was 63.1 years(range : 44 to 76 years). With the Height tracer (extraoral tracing device) in place the subject was instructed to go through the entire range of mandibular movements. The extreme lateral pathway of the incisor point, the so-called Gothic arch, was thereby inscribed by the stylus on the tracing plate. The mandibular movements in this study were peformed voluntarily by the subject(self guided technique) and guided by the dentist(chin-point technique and bimanual technique). The Gothic arch tracings were analysed and the Gothic arch angles and eccentric movement distances were measured. The results were as follows : 1. The apex position of the Gothic arch tracings of mandibular movements in edentulous patients varied both anterioposteriorly and mediolaterally. 2. The Gothic arch tracing had some lateral deviation during protrusion. 3. The average Gothic arch tracing angle was $136.7{\pm}12.0^{\circ}$ by subjects self guided technique, $135.7{\pm}5.9^{\circ}$ by chin-point technique, $136.6{\pm}6.5^{\circ}$ by bimanual technique. But there were no statistical differences in the reliability among the three techniques. 4. The average mandibular eccentric movements were irregular and the mandibular eccentric movement distances varied with a wide range.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제33권3호
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• pp.218-224
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• 2011

Purpose: The purpose of this study is to evaluate the post-operative skeletal stability after surgical correction of patients with mandibular prognathism by bilateral sagittal split ramus osteotomy (BSSRO) and to evaluate the horizontal relapse tendency after the surgery. Methods: Twenty-six patients with Class III dental and skeletal malocclusion were selected for this retrospective study. Fifteen of them underwent BSSRO for mandibular setback and eleven of them underwent two-jaw surgery (Lefort I and BSSRO). In each patient, lateral cephalometric radiographs were taken pre-operatively, post-operatively within 1 week, and post-operatively after eight months. After tracing of the cephalometric radiographs, various parameters were measured. The analyses were done by linear measurement to evaluate the change in position of hard tissue B point, pogonion and mandibular plan angle by examination on lateral cephalograms. Results: The horizontal relapse rate was 27.1% at B point and 31.6% at pogonion in patients who underwent BSSRO. The horizontal relapse rate of the group where the amount of correction exceeded 10 mm was 25.69% at B point. Conclusion: There were no statistical differences on the magnitude of setback and direction of rotation of the mandible in mandibular stability. There were also no statistical differences between single mandibular surgery and two-jaw surgery for mandibular stability.