• Journal of Korean Dental Science
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• 제16권2호
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• pp.149-155
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• 2023

Purpose: The purpose of this study was to evaluate whether the presence of a space maintainer affects the accuracy of an intraoral scanner. Materials and Methods: The maxillary primary first molar typodont tooth was removed from the primary dentition typodont model and a band and loop type space maintainer was delivered. After the model was connected to a dental phantom, intraoral scan was performed using TRIOS 4 (3Shape A/S, Copenhagen, Denmark). The scan was repeated with the same technique without the space maintainer. Each scan was performed 10 times. All scan files into a GOM inspect 2018 software and evaluated the accuracy. The accuracy was evaluated on trueness and precision, and calculated using the root mean square value. Result: When there was a space maintainer in the oral cavity, the trueness value was 0.10±0.02 mm and the precision value was 0.15±0.03 mm. In the absence of the space maintainer, the trueness value was 0.12±0.03 mm and the precision value was 0.16±0.04 mm. There were no significant differences depending on the presence of a space maintainer (P>0.05). Conclusion: Within the limits of this study, the accuracy of the intraoral scanner was not influenced by the presence of space maintainer.

• 구강회복응용과학지
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• 제40권2호
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• pp.100-106
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• 2024

조기 교정치료의 개입은 종종 성장하는 치열을 정상 교합으로 유도하는 것에서부터 시작된다. 유치의 상실로 인한 맹출 실패를 예방하는 가장 간단한 방법은 밴드 및 루프와 같은 공간 유지장치를 부착하는 것이다. 밴드 및 루프 공간 유지장치는 밴드의 픽업 인상 과정을 거쳐야 하며, 시멘트 소실과 탈회, 인접치의 locking과 같은 문제들을 갖고 있다. 이러한 문제를 해결하기 위해서 CAD/CAM을 이용한 band가 필요 없는 공간유지장치가 개발되었다. 본 증례는 밴드 없이 CAD/CAM을 이용하여 하악 제2소구치가 성공적으로 맹출할 수 있었기에 이를 보고하는 바이다.

• 대한소아치과학회지
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• 제24권1호
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• pp.186-194
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• 1997

The three child patients aged 3 to 5 years were worn by anterior space maintainer which are fixed type after missing of anterior teeth due to nursing caries, and were taken periodic follow check up. The results are : 1. At missing of anterior teeth, fixed space maintainer can be used. 2. Increased esthetic satisfaction and positive change of social behavior can be observed by these child patients. 3. Some phonations can be changed definitely after wearing the fixed space maintainer.

• 대한소아치과학회지
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• 제24권3호
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• pp.704-709
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• 1997

Space maintainers needs following extraction of primary molars, due to severe dental caries under general anesthesia. Delivery of conventional space maintainers has three of the disadvantages of the method, there being a impression taking and time consuming due to laboratory procedure, and delivery problem due to relaxed tongue. For this problem improved, modified space maintainer is prefabricated before procedure, and adjust, delivery in operation room, favorable results were obtained. The following results were obtained. 1. Delivery time is very reduced than conventional space maintainers. 2. After space maintainer delivery, follow check-up, without impingement of soft tissue, distortion of wire. After space maintainer delivery, continuous research is required so that space maintainer delivery is applied to usual dental treatment, and it is necessary of long term research.

• 대한소아치과학회지
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• 제1권1호
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• pp.49-55
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• 1974

Electromyographic studies were performed on the action of the masseter muscles. Among the children aged from 6 to 8 years, ten children with normal occlusion and another ten with space maintainer were selected. The children were divided into 3 groups. They were: 1) A group: Children who removed space maintainer 2) B group: Children who inserted space maintainer 3) C group: Children with normal occlusion. The electromyogram was recorded with 4 channel polygraph. (Grass model VII) Electrodes which were cup-typed gold disks, 9 millimeters in the diameter, were located on the superficial layer of masseter muscles. The electromyogram was recorded in the physiologic rest position, molar occlusion, chewing movement, protraction, left lateral movement, and right lateral movement. The conclusions were as follows. 1. In the physiologic rest position, lateral movement, the electrical potentials of the masseter muscles were not changed clearly in each groups. 2. In molar occlusion, chewing movement, The electrical potentials of the masseter muscles of the B group were almost 10% higher than those of A group, and were almost 60-70% in comparision with C group. 3. In protraction, the electrical potentials of the masseter muscles of the B group were almost 40% higher than those of A group, and were almost equal to C group. 4. The electrical activities of the masseter muscles in the mandibular movements were in the following order: (1) Molar occlusion (2) Chewing movement (3) Protraction (4) Lateral movement.

• 대한치과의사협회지
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• 제11권4호
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• pp.277-280
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• 1973

The author observed the changes of dental arch dimensions and compared spae-maintainer group with non-space-maintainer group after primary tooth extraction. The results were as follows 1) The rate of growth of dental arch of expeirmental group in intercanine width and in inter-1st molar width was more rapid than that of the control group. 2) Arch length is almost no dimensions but it was slightly decreased in lower arch. 3) Dental arch growth and tooth eruption were stimulated by space-maintainer appliance, so it is the best way to replace a new appliance at least once a year. 4) It is thought that satisfactory conclusions in this observation must be researched successively until the mixed dentition completes.

• 대한소아치과학회지
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• 제24권4호
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• pp.776-780
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• 1997

Patient with alveolar abscess due to dental caries with severe alveolar bone loss, severe tooth mobility, root resorption need extraction of tooth because it is impossible to carry out pulp treatment and restoration by using conventional method. Early loss of primary molar might cause masticatory interference, extrusion of opposing tooth, problem in maintaining space and interference on eruption of permanent tooth. Especially, early loss of primary second molar before the eruption of permanent first molar might cause space closure by mesially erupted permanent first molar and impaction of second premolar. In such a case, distal shoe space maintainer and removable space regaining appliance was the first choice of treatment. But, distal shoe space maintainer need precise adaptation and might cause chronic inflammation if the oral hygiene is poor. In a case using removable space regaining appliance, patient's cooperation is most important. If the distal root of primary second molar is comparably sound and alveolar abscess with alveolar bone loss is localized at mesial root, hemisection should be carried out for precise guide to eruption of the permanent first molar, restoration of masticatory fuction and solution to the discomfort of the patient

• 대한치과의사협회지
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• 제12권4호
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• pp.241-244
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• 1974

The author measured the masticatory efficiency in the 50 children with normal sound dentition, in the 20 children with amalgam filling and in the 20 children with fixed type space maintainer i.e. in the 90 children in total and got the following results. 1. the masticatory efficiency were 53.8% in children with normal sound primary dentition. 2. The masticatory efficiency 48.3% in children with amalgam filling and 40.0% in children with fixed type space maintainer 3. The masticatory efficiency of children were 60.0% of adult's in normal dentition.

• 대한치과의사협회지
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• 제22권8호통권183호
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• pp.646-646
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• 1984

• 대한치과의사협회지
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• 제27권11호통권246호
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• pp.1001-1007
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• 1989