• The Journal of Advanced Prosthodontics
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• 제15권6호
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• pp.302-314
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• 2023

PURPOSE. The aim of this study was to classify the shapes of retromolar pads and assess their morphometric differences using a 3D model. MATERIALS AND METHODS. Two hundred fully edentulous or Kennedy Class I partially edentulous patients (400 retromolar pads) were enrolled. Scan data of the definitive mandibular casts produced through functional impressions were obtained using a 3D laser scanner. Seven parameters (transverse diameter, longitudinal diameter, transverse-contour length, longitudinal-contour length, longitudinal/transverse diameter ratio, longitudinal/transverse-contour length ratio, and angle of the retromolar pad line to the residual alveolar ridge line) were measured using image analysis software. Subsequently, the pads were classified according to the shape. Statistical analyses were performed using 95% confidence intervals. RESULTS. Classifying the retromolar pads into three shapes led to high intra-examiner reliability (Cronbach's alpha = 0.933). The pear shape was the most common (56.5%), followed by oval/round (27.7%) and triangular (15.8%) shapes. There were no significant differences between the left and right sides according to the shape and no significant differences in any parameter according to age. The transverse diameter and longitudinal/transverse diameter ratio differed between sexes (P < .05). The triangular shape had a significantly different transverse diameter, transverse-contour length, longitudinal/transverse diameter ratio, and longitudinal/transverse-contour length ratio compared with the pear and oval/round shapes (P < .05). CONCLUSION. From a clinical reliability standpoint, classifying retromolar pads into three shapes (oval/round, pear-shaped, and triangular) is effective. The differences in the sizes among the shapes were attributed to the transverse measurement values.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제17권4호
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• pp.389-395
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• 1995

Adenoid cystic carcinoma is malignant neoplasm belonging to a group of tumors of salivary gland origin. It is an aggressive tumor characterized by slow growth and incidious destruction of surrounding tissues. Perineural invasion is a prominent feature. Spread to regional lymph node is rare, other than by direct extension. Distant metastasis are more common. We experienced a 65-year old female with adenoid cystic carcinoma of minor salivary gland in retromolar pad.

• 구강회복응용과학지
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• 제35권2호
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• pp.64-71
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• 2019

무치악 환자의 교합평면 수준을 결정할 때 후구치삼각융기는 흔하게 이용하는 해부학적 지표 중 하나로 연조직 덩어리이며 의치의 의해 피개 되어야 한다. 후구치삼각융기의 형태는 다양성을 보이며 이는 최후방 치아 발거에 따른 치유과정을 통해 형성되는 변화는 필연적이기 때문이다. 본 문헌고찰은 후구치삼각융기의 형태에 있어서 해부학적 관계와 임상적인 가치를 고려하고 형태적인 분류에 관해 고찰하고자 하였다.

• 대한치과의사협회지
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• 제23권11호통권198호
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• pp.913-913
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• 1985

• 대한치과보철학회지
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• 제43권1호
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• pp.41-51
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• 2005

Statement of problem. Anatomic landmarks have been used in the orientation of occlusal plane and the determination of vertical dimension for edentulous patients. Such as labial vestibules of anterior region and hamular notches, retromolar pads of posterior region are very useful anatomic landmarks for fabrication of occlusion rim because they are to be identified on master casts. Therefore, if average distances between landmarks of maxillae and mandible in dentate subjects are measured and applied, not only occlusal plane but also vertical dimension can be established initially. Purpose. The purpose of this study is to measure vertical distances between anatomic landmarks and to present a guide to the orientation of occlusal plane and the determination of vertical dimension of edentulous patients. Material and method. Upper and lower border-molded casts were made in 93 Korean dentulous subjects, mean age 25 years. Incisal edges of central incisors, bottoms of labial vestibules, hamular notches and the half level of retromolar pads were marked on casts. Measurements of vertical distances from incisal edge of central incisor to the bottom of labial vestibule, between upper and lower bottoms of labial vestibules, from hamular notch to retromolar pad and from hamular notch to the occlusal plane established by the incisal edge of maxillary central incisor and mesiopalatal cusps of both maxillary first molars were made on each cast. Results and conclusion. 1. The mean distance from the incisal edge of central incisor to the bottom of labial vestibule was 20.8mm(SD 1.7) on upper casts and 17.3mm(SD 1.4) on lower casts. 2. The mean distance between both bottoms of labial vestibules of upper and lower casts was 35.0mm(SD 2.7). 3 The mean distance from hamular notch to the half level of retromolar pad was 5.0mm(SD 1.3). 4. The mean distance from hamular notch to occlusal plane was 7.9mm(SD 1.5). 5. Distances from incisal edge of central incisor to labial vestibule on lower casts(P<0.01) and from hamular notch to retromolar pad(P<0.0001) were greater in male than in female.

• 대한치과보철학회지
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• 제27권1호
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• pp.25-29
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• 1989

The author analized 17 complete denture patients with lateral cephalometric roentgenograms and following results were obtained: 1. The angle between the Ala tragus line and the occlusal plane was $4.38^{\circ}$. 2. The angle between the Ala tragus line and the Frankfort horizontal plane was $13.68^{\circ}$. 3. The line between the mouth corner and the retromolar pad was more parallel to the occlusal plane than the Ala tragus line.

• 구강회복응용과학지
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• 제19권3호
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• pp.153-168
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• 2003

It is very important to arrange the artificial teeth correctly in bucco-lingual (labio- lingual) relation in reconstrcting dentition. Although many anatomic landmarks and techniques have been reported over the years, they are based on westerns. So this study was performd to examine the horizontal relations of mandibular teeth in Korean dentulous adults. 200 volunteers(mean age 22.9) who had natural dentition were selected. The impressions were taken with irreversible hydrocolloid impression material and mandibular study models were fabricated using class I dental stone. Then they were measured with 3-dimensional measuring device specially designed for this study. The results were as follows ; It is better to consider the lingual cusps of the lower posterior teeth as a guide than the linguoaxial surfaces of the lower posterior teeth, arranging the lower posterior teeth buccally to the line which starts from the mesial aspect of the lower canine and continue backward to the lingual aspect of the retromolar pad. It is better to arrange the fossae of the lower posterior teeth buccally to the line which starts from the cusp tip of the lower canine and continue backward to the top of the retromolar pad. The positions of the lower posterior teeth in the denture-bearing area ; considering the fossa as a guide, the 2nd premolar was positioned in center. considering the buccal cusp as a guide, the 1st molar and the 2nd molar were positioned in center. the distance ratio(d/a) was incresed constantly from the lower canine to the 2nd molar d ; the distance between the buccal vestibule(the lowest point) and the buccal cusp tips of the lower posterior teeth. a ; the distance between the buccal vestibule(the lowest point) and the lingual vestibule(the lowest point). The lower canine was positioned lingually($0.11{\pm}0.13$) than the labial vestibule, and the central incisor and the lateral incisor were positioned almost in the imaginary perpendicular plane of the labial vestibule(the lowest point).

• 구강회복응용과학지
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• 제21권1호
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• pp.83-93
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• 2005

This study was designed to investigate the fitness of adjustable dental impression trays. The size and shape of these trays were designed from the results of the dental arch size of Korean adults. Tray samples were made by CAD-CAM working. A hundred dental students(male:50, female:50) were selected for taking irreversible hydrocolloid impression using these trays. The author measured the width and length of impression material on the several measuring points. The results obtained were as follows : 1. Uniform impression material thickness was achieved by controlling the width of the tray using stops and beveled guides. 2. In the upper tray, the impression material thickness was measured to be rather great showing thickness of the labial vestibule 8.3 mm and the midpalatal part 8.6 mm. 3. In the lower tray, length of the impression material of the labial vestibule of first, second premolar contact point was 7.8 mm, and thickness of the lingual part of premolars(1.8 mm) and molars(1.9 mm) showed small values. 4. In the lower tray, the impression material thickness of the buccal shelf area(0.2 mm) and the retromolar pad area(0.6 mm) was measured to be too small.

• 대한치과보철학회지
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• 제52권4호
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• pp.346-351
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• 2014

흡착 의치는 의치상연 주위 전체를 가동 점막으로 봉쇄하여 연하나 교합 시 의치상 내면에 일시적으로 음압을 형성하여 의치의 유지와 안정을 강화한다. 본 증례의 환자는 81세의 남자 환자로 새로운 의치를 제작하고 싶다는 주소로 내원하였다. 의치의 유지와 저작 효율에 대한 환자의 높은 요구도를 고려하여 흡착 의치를 통한 총의치 제작을 계획하였다. 하악 후구치 융기 부위를 가압하지 않은 채로 예비 인상을 채득 후 상하악 진단모형을 제작하였다. 이후 개인 트레이 제작 후 최종 인상 채득과 동시에 고딕 아치 기록을 시행하여 중심위 및 수직 고경을 채득하였으며, 상악에는 해부학적 치아, 하악에는 비해부학적 치아를 배열하여 설측 교합을 형성하였다. 이상과 같이 완전 무치악 환자에서 하악 흡착 의치를 통한 총의치 수복은 만족스러운 유지와 기능을 회복할 수 있었기에 본 증례를 보고하고자 한다.

• 대한치과보철학회지
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• 제26권1호
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• pp.153-169
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• 1988

There is a little scientific documentation reporting the stress, distribution to the edentulous mandible by different concepts of occlusal scheme. So, this study was to investigate the hypothesis that the magnitude and distribution of the occlusal stresses, transmitted through a mandibular complete denture base to the edentulous mandible, would be influenced by the lingualized occlusion. This investigation was performed to analyze the stresses induced in a three-dimensional photoelastic edentulous mandible, when a load is applied to the denture arranged into lingualized occlusion in centric relation, lateral and protrusive functional position. The mounted denture on a Dentatus Type ARO articulator was loaded in a pure vertical direction with 15kgs on the center of articulator in each case and the stresses were frozen into epoxy edentulous model at $127^{\circ}C$ in the stress freezing furnace. The stress-frozen epoxy models were sliced with diamond disc saw into 4mm thick. The slices were examined with a circular polariscope. The results were as follows: 1. In centric relation, the stresses were low at anteriors, and gradually increase to the premolar, molar area and highest at the first molar and gradually decrease from the second molar and lowest at the retromolar pad region. The lingual side showed higher stresses than labiobuccal side. 2. In lateral functional position, the working side showed higher stresses than the balancing side. In working side, the lingual side showed higher stresses than the buccal side and in balancing side, the buccal side showed higher stresses than the lingual side. 3. In protrusive position, stress distribution was symmetrical on the posteriors and the stresses were concentrated at the labial side of the anteriors.