• 대한치과보철학회지
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• 제41권5호
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• pp.565-581
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• 2003

Statement of problem : A scientific examination and understanding of overall aspects of the natural dentition is the first step involved in making a satisfactory selection in the shade of an aesthetic prosthesis. Proper natural shade selection of the prosthetic restoration that is in harmony with the remaining dentition is as important aesthetically, as harmony of form and function in the anterior dentition. Clinically, the most commonly applied method of shade selection has been visual, but because of the subjective nature inherent to this method, shade selection results are variable and can be influenced by such factors as the technician, the type of shade guide used, and the type and intensity of the lighting. Purpose : The purpose of this study was to develop a more objective and scientific approach to examining and understanding the shade of teeth, which has in turn lead to the development of a number of shade analysis devices that present a more objective method of shade analysis. Material and Method : In this study, the shades of healthy anterior teeth were examined and analyzed using the recently developed digital shade analysis of the $ShadeScan^{TM}$ System. The study examined 80 individuals in their twenties, 40 males and 40 females, presenting 6 healthy, unrestored maxillary anterior teeth. Tooth brushing and oral prophylaxis were performed prior to evaluation. The ShadeScan handpiece was used to acquire images of the 6 maxillary anterior teeth. These images were analyzed using the Vita/Classical mode of the $ShadeScan^{TM}$ Software, and shade maps of each tooth were acquired and divided into cervical, middle, and incisal thirds. The shade distribution of each third, left and right symmetry, and gender differences were investigated and analyzed. Results : The results of the study are as follows : 1. An overwhelming majority of the examined teeth were found to possess shades belong to Group A, with the greatest variations occurring at the middle and cervical thirds of the maxillary central and lateral incisors, in both male and female subjects. 2. Canines of both male and female subjects showed left and right symmetry with uniform shade distribution of A4 and C4, while the lateral and central incisors showed left-right symmetry of the incisal 1/3 with a uniform shade distribution of A2 and A3 shades 3. No significant differences in shade distribution were seen between genders in maxillary canines, whereas maxillary central and lateral incisors showed differences at the middle and cervical thirds between male and female subjects The results of this study show that with the exception of maxillary canines, maxillary anterior teeth display a diverse shade distribution as well as gender differences. Conclusion : Clinically, when making a shade selection using the existing shade guide, one must consider the fact that even a single tooth consists of a variety of shades. The results of this study show that when selecting a shade from a number of groups is difficult, shades from A group are the most consistent with the natural shade or maxillary anterior teeth.

• 대한치과보철학회지
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• 제30권4호
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• pp.508-525
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• 1992

The purpose of this study was to evaluate the effect of some resistance form designs on the bond strength of resin-retained prosthesis. Six sub-groups are designed in natural teeth group and resin teeth group . The framework designs in natural teeth group: 1) no groove preparation 2) groove at the center of distal surface 3) groove at the distobuccal line angle 4) 45 degree lateral load with no groove 5) 45 degree lateral load with center groove 6) splint two teeth with no groove. The framework designs in resin teeth group: 1) no groove preparation 2) groove at the center of distal surface 3) groove at the distobuccal line angle 4) metal covered the 1/2 of distal surface 5) metal covered the 1/2 of mesial surface 6) metal extended over the 114 of buccal surface. Specimens were treated electrolytic etching by Oxy-Etch and cemented with Panavia EX. Failure load was measured by Instron. Another 30 specimens were carried out fatigue tests by MTS 810 fatigue testing machine for 5000 cycles at different load level. The following results were obtained from this study. 1. The failure load was significantly increased by resistance forms. 2. The failure load was not increased by increase of total surface area bonded with teeth. The distal surface area played an important role in failure load. 3. In 45 degree lateral load group, the failure load was decreased significantly than that of in vertical load group. 4. Bond failure modes between static test and fatigue test exhibited no differences.

• 구강생물연구
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• 제42권4호
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• pp.208-215
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• 2018

The purpose of this study was to identify the risk of dysphagia among patients that visited prosthodontics department, and evaluate the difference in risks arising from oral conditions and disease in order to preliminarily intervene the various influencing factors of dysphagia. A questionnaire was given to patients that were aged 65 years or older who visited the prosthodontics department between September to December 2017. The data was collected and analyzed using the t-test, $x^2-test$ and logistic regression analysis. The mean age of the patients was 75 years. Out of 300 patients, 206 patients (68.7%) had a risk of dysphagia. There were statistically significant differences between the -non-risk and risk groups, which included the number of natural teeth, total number of teeth including prosthesis, denture use, denture discomfort, number of tooth brushing, oral dryness, digestive system diseases, and musculoskeletal diseases. Among these, oral dryness was a risk factor while the total number of teeth, including natural teeth and prostheses, served as a protective factor. More than half of the elderly patients were at risk of dysphagia. Oral dryness is influenced by many factors and it should continuously be managed. Patients should fully recover their masticatory function by preserving the remaining teeth and compensating for the missing teeth. A dental practitioner should be fully aware of the risk of dysphagia in elderly patients and be able to intervene and offer proper patient health care in advance through treatment guidelines and education.

• 구강회복응용과학지
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• 제36권4호
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• pp.232-241
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• 2020

목적: 이 연구는 정출된 자연치와 대합되는 임플란트에 발생하는 합병증과 그 양상에 대해 고찰하여 대합치 정출이 임플란트 합병증에 어떠한 영향을 미치는지에 대해 알아보고자 하였다. 연구 재료 및 방법: 조선대학교 치과병원에서 2006년부터 2018년 사이에 임플란트치료를 받은 환자 중에서 유지관리기간이 최소 5년 이상이면서 구치부 임플란트와 대합되는 자연치가 방사선 사진상으로 측정 및 비교 가능한 임플란트만을 선택하였다. 정출된 구치부 자연치와 대합되는 임플란트를 실험군인 Group 1 (n = 167: 상악(Group 1max) = 92, 하악(Group 1man) = 75)과 정출소견이 없는 구치부 자연치와 대합되는 임플란트를 대조군인 Group 2 (n = 656: 상악(Group 1max) = 272, 하악(Group 1man) = 384)로 분류하였다. 두 그룹 사이에 합병증의 발생빈도와 변연골 흡수에 대해 조사하였다. 결과: Group 1과 Group 2 사이에 합병증의 발생빈도는 통계학적으로 유의성이 있었다. 특히, 상악골의 치조골 소실 빈도와 치조골 소실 양이 통계적으로 유의한 차이를 나타내었다. 결론: 정출된 자연치는 대합되는 임플란트에 골흡수를 비롯한 합병증을 더 빈번하게 유발할 수 있다.

• 구강회복응용과학지
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• 제40권2호
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• pp.82-90
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• 2024

치조제의 조직 변화, 의치 또는 지대치의 파절 등으로 인해 국소의치의 수리가 필요한 경우가 종종 발생한다. 기존 국소의치의 금속 구조물에 맞는 보철물을 제작하면 몇 가지 장점이 존재한다. 환자의 경제적 부담이 줄어들고, 새로운 의치를 제작하기 위해 여러 번 내원할 필요가 없다. 자연치아가 파절되어 의치를 수리할 때 사용되는 인공치는 자연치아와 유사한 형태를 갖기 어려우며, 심미적인 인공치 수리를 위해서는 환자 개개인의 치아 형태와 유사한 맞춤형 인공치 제작이 필요하다. 최근에는 CAD/CAM 기술을 이용한 기존 국소의치에 맞는 보철물을 제작하여 높은 유지력과 적합도를 확보할 수 있으며, 맞춤형 인공치아를 디자인하여 더욱 심미적이고 조화로운 의치 수리가 가능하다. 디지털 방식을 이용하여 기존 국소의치에 맞춤형 보철물과 인접치열을 미러링한 맞춤형 인공치를 제작하여 의치를 수리한 증례로 시간과 비용을 절약하고 과정을 단순화하면서 심미적, 기능적으로 만족스러운 결과를 얻었기에 이를 보고하는 바이다.

• Journal of Oral Medicine and Pain
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• 제23권4호
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• pp.457-473
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• 1998

This study was performed to investigate the morophological and positional correlation between the upper cervical vertebra, the oral structures and the pharyngeal tissues, and the correlation of these anatomical structures with dental features, such as teeth wear area nad tooth contact status, etc. Seventy patients with temporamandibular disorders and sixty three dental students without any signs and symptoms in head and neck region were selected for this study. All they had natural dentition without any fixed and removable protheses. Teeth wear area and arch width wre measured from the upper dental cast, tooth contact status were observed by T-Scan system$^\textregistered$ and four cephaloradiograpohs were taken from four head postures, namely, natural(NHP), forward(FHP), upward(UHP), and downward head postiure(DHP). 22 cephalometric items were measured on the films and the data were processed with SAS statistical program. The result of this study were as follows : 1. In normal group, angle of cervical vertebra tangent and of between hard and soft palate were broader in female subjects than those in male subjacets, but distance from subocciput to axis, size of soft palate, and pharyngeal space width were larger in male subjects. 2. In normal group with natural head posture, the items correlated each others from the three anatomical regions were distance between first nad second vertebra in posterior part, distance from the lingual surface of lower anterior teeth to anterior surface of soft palate, and distance from the hyoid bone to third vertebra. 3. Three set of items showed significant correlation each other in the four head postures in normal group. First set was the angle between hard and soft palate and the idstance from subocciput to posterior arch of first vertebra, second set was the distance between first and second vertebra in posterior part and the teeth wear area, third set was number and force of tooth contact and length of soft palate and distance from anterior tip of hyoid bone to mandibular plane.

• 대한치과보철학회지
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• 제46권4호
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• pp.381-395
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• 2008

서론: 임플랜트와 자연치가 혼재하는 증례에 있어서 보철물의 연결여부와 그 결과에 대해 논쟁이 많이 있어왔다. 본 연구에서는 임플랜트와 자연치를 이중관으로 연결했을 경우에 치조골 내에서 임플랜트 주변 조직의 하중에 대한 응력의 양상을 분석하여 자연 치와 임플랜트를 연결하는 보철물의 방식으로 이중관의 사용가능성을 비교 분석하고자 하였다. 연구재료 및 방법: 실험군으로서는 한 개의 자연치아와 한 개의 임플랜트를 이중관으로 연결한 모델을 사용하고, 대조군으로 두 개의 임플랜트를 이중관으로 연결한 모델을 사용하여 응력분포의 차이를 비교분석하였다. 임플랜트와 자연치 각각 통상적인 금합금을 사용하여 내,외관을 모델링한 후 각각의 외관을 연결한 구조를 형성한다. 내관과 외관은 $6^{\circ}$의 경사도 (taper)로 형성하고 내외관 사이의 공간을 인정하여, 하중을 가했을 경우 내외관 사이에 합금의 마찰력과 변위를 계산하여, 그 결과가 골내 임플랜트의 응력 분포에 영향을 줄 수 있도록 실험모델을 형성하였다. 하중은 일반적인 저작력의 크기로 임플랜트 부위와 자연치 부위에 각각 부여하여 응력의 차이를 비교하였으며, 최종적으로 대조군과의 차이를 비교하고자 하였다. 하중 조건은 임플랜트와 자연치아 사이, 임플랜트 후방, 전방부 자연치아의 사이에 하중을 가하였으며, Load case 1, 2, 3로 분류하였다. 실험을 위해서 ANSYS Version 8.1을 사용하여 3차원 유한 요소 분석을 시행하였다. 연구성적: 지대주에 가해지는 응력 - 최대 응력은 실험군이 대조군에 비해 각각 2.4 (Load Case1), 1.02 (Load Case2), 0.46 (Load Case3)배 높게 나타났으며,Load Case3의 경우 대조군의 최대응력이 더욱 높게 나타났는데, 이것은 전치부 치아의 경우 하중을 효과적으로 분산하기 때문인 것으로 보인다. 악골내에 가해지는 응력 - 악골내에서 최대 응력은 실험군이 대조군에 비해 각각 1.69 (Load Case1), 1.26 (Load Case2), 1.93 (Load Case3) 배 크게 나타났다 결론: 임플랜트와 자연치아가 혼재된 경우, 이중관으로 상부 보철물을 연결한 경우, 임플랜트만으로 구성된 대조군에 비해, 임플랜트 및 임플랜트 식립 부위의 악골에 가해지는 최대 응력은 1.02 에서 2.4배 가량 높게 나타났다. 자연치아의 움직임이 임플랜트의 경부 및 악골 내에 응력을 집중시킨 것으로 보이며, 자연치아가 있는 악골부위에서는 응력이 거의 발생하지 않았다. 본 실험의 경우 자연치아와 임플랜트에서 모든 하중을 받는 것으로 계산하였고, 실제 가철성 의치에서 나타나는 점막의 영향을 배제하였기 때문에, 실제 임상에서는 후방 임플랜트에 미치는 최대 응력의 크기는 2.4배 이하일 것으로 추정할 수 있다. 앞으로, 실제 임상에 적용하였을 경우, 임플랜트에 미치는 영향 및 자연치아에 미치는 결과에 대한 연구가 필요할 것이다.

• 보건의료산업학회지
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• 제10권3호
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• pp.123-133
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• 2016

Objectives : This study analyzed the effect of health-related characteristics of middle-aged and elderly people on the number of existing permanent teeth by considering each age group through the improvement of health-related characteristics. This study contributes by offering fundamental information on the prevention of dental diseases and on developing an education program that can be used by dental health businesses to improve dental health. Methods : This study used primitive data of the sixth term of the first year and the second year and selected a total of 4,393 people as the final research subject. In order to determine the factors that influence the number of existing natural teeth, confounding factors were considered, and regression analysis using general linear models was done. Results : According to the results of this research, the middle-aged and elderly groups have more existing permanent teeth in the following three cases: 1. Talking is comfortable when daily brushing frequency is 3 times or more. 2. Self-recognition of dental health condition is good. 3. Number of dental caries present in permanent teeth is low. Conclusions : For a and medical system, a dental health care system that takes into consideration the lifespans of people must be legislated and implemented.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제27권5호
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• pp.457-463
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• 2001

In the unconscious patient with general muscle rigidity, the natural teeth can be luxated and then bite wounds may be occurred around lip, owing to the pathologic involuntary self-biting habit. If the forceful biting is generated continuously, the teeth may be avulsed and aspirated into the aerodigestive tract with the infection of biting wound. For the prevention of pulmonary aspiration of the teeth and wound infection, the biting teeth should be cared before the fact. The authors treated the teeth as endodontic drainage with removal of the crown or iodoform gauze drainage into the socket with extraction of the teeth. The prognosis was more favorable without biting wounds.

• 대한치과의사협회지
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• 제55권3호
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• pp.249-256
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• 2017

Gingival recession is one of the common mucogingival problems during the orthodontic treatment. The causes of the gingival recession are similar to gingival recession in patients with periodontal diseases. Accumulation of bacterial deposits around the natural teeth induces the gingival inflammation and gingival recession occurs in the teeth with the lack of the supporting bone. However, malpositioned teeth which are labially positioned teeth or rotated teeth are more risky for gingival recession. Once root is exposed to oral cavity due to gingival recession, the orthodontic tooth movement is compromised and esthetic problems appeared. In addition, excessive gingival recession over the mucogingival junction jeopardizes the oral hygiene control, which has a risk of further gingival recession and bone loss around the tooth. To cover exposed root or to prevent further gingival recession, mucogingival surgery with gingival graft is recommended for the patients under orthodontic treatment. This case report aimed to present the mucogingival treatments of gingival recession observed during orthodontic treatment. Case I had had initial slight gingival recession before the orthodontic treatment. However, during the retraction phases, the gingival recession progressed and the periodontal treatment was referred. In case II, miller Class III gingival recession was occurred after correction of rotation. Both cases were treated by coronally advanced flap with free gingival grafts and recovered to the level of adjacent teeth despite of complete root coverage was not achieved in Case II. After periodontal treatment, orthodontic treatment was successfully completed. In conclusion, mucogingival surgery during the orthodontic treatment is recommended for the successful orthodontic treatment as well as periodontal health.