• 대한치과보철학회지
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• 제8권1호
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• pp.9-14
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• 1968

A total of 11,039 permanent missing teeth and their 2,696 prosthetic replaced teeth in 6,123 Korean patients were selected for this study, Analyzing the data according to age, sex, jaw and the location, following results were obtained. 1. Tooth mortality and replacement were higher in female than in male. 2. Replaced teeth were only 24 percent of missing teeth. 3. More teeth were extracted and replaced on lower jaw in young patients and on upper jaw in old patients. 4. There are no significant difference in right and left sides of both jaws in missing and replaced teeth, respectively. 5. First molar was the highest percentage in both mortality and replacement. 6. Upper tooth mortality and replacement were higher in anterior portion and lower in posterior portion.

• 대한소아치과학회지
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• 제37권1호
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• pp.91-96
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• 2010

많은 연구에서, 유치와 그 계승 영구치의 선천적 결손 간에는 상당한 연관관계가 있는 것을 보고하였다. 그러나 하악 전치부에서, 유치의 선천적 결손에도 불구하고, 그 계승 영구치는 정상적으로 존재하는 증례가 임상적으로 종종 관찰되기도 한다. 본 연구의 목적은 한국 어린이에서 하악 유절치와 그 계승 영구치의 선천적 결손 간의 상호 연관관계를 평가하는 데에 있다. 2005년 1월 1일부터 2008년 9월 5일까지 서울대학교치과병원에 내원하여 파노라마 방사선사진을 촬영한 6세 이하의 남녀 어린이 총 14,307명을 대상으로 하악 전치부의 치아양상을 관찰하여 유치와 영구치의 선천적 결손 관계를 평가하여 다음과 같은 결과를 얻었다. 1. 하악 유절치의 결손률은 0.24%였으며, 하악 유절치가 존재 시 후속 영구치가 존재할 승산(odds)은 7163.5였으며, 유절치의 결손시 후속 영구절치가 존재할 승산(odds) 0.79였다. 2. 하악 유절치 결손의 증례 중 후속 영구치가 모두 존재하는 경우는 44.12%였다. 유절치의 양측 결손 시 후속 영구치가 하나라도 존재할 승산(odds)은 유절치 편측 결손 시에 비하여 1.57 배였다. 3. 유절치 결손이 있을 때 유절치의 편측 결손일 승산(odds)은 여자가 남자에 비해 2.2 배였다. 또한, 유절치 결손이 있을 때 후속 영구절치가 존재할 승산(odds)은 남자가 여자의 경우에 비하여 2.22 배였다.

• Journal of Korean Dental Science
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• 제3권1호
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• pp.17-24
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• 2010

Objective : To investigate the prevalence of dental anomalies and to determine the associations between dental anomalies in permanent teeth Materials and methods : The samples were 1,240 patients (760 females and 480 males, mean age=15.1 years) who visited the Samsung Medical Center. Dental anomalies were diagnosed using pre-treatment dental casts, radiographs, clinical examinations, and medical/dental histories. Prevalence and association were investigated according to gender and sidedness. The Chi-square test was performed for statistical analysis. Results : The most common missing tooth was the lower lateral incisor, followed by the lower and upper second premolars. This particular dental anomaly is characteristic of the East Asian population (prevalence of congenital missing tooth=12.3%). The upper anterior area was the most frequently affected area (prevalence of supernumerary tooth was 1.5%). The presence of a supernumerary tooth was more prevalent in males than in females (p<.05, odds ratio=3.2). The most frequently affected tooth was the upper canine (prevalence of impacted tooth=4.3%). Unilateral impaction of the upper canine occurred significantly more often compared to bilateral impaction (p<.001). The prevalence of peg lateralis was 2.7%. The presence of congenital missing tooth was closely associated with peg lateralis (p<.01). If children aged 7~8 years have peg lateralis, the rest of the teeth should be checked for congenital absences. Conclusion : The early detection of dental anomalies and understanding of their associations help clinicians determine the appropriate treatment timing and methods of dealing with these anomalies.

• 치과방사선
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• 제20권1호
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• pp.79-89
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• 1990

The incidence and several characteristic features of fused and geminated teeth were studied radiographically, with full mouth periapical radiogram and pantomogram, in 4201 patients of mixed dentition and 5358 patients of permanent dentition. The obtained results were as follows: 1. The prevalence was revealed to 2.86%, 0.32%, 0.33%, and 0.06% in deciduous fused tooth, permanent fused tooth, deciduous geminated tooth and permanent geminated tooth respectively, and these anomalies were occured in female more than male. 2. Fused teeth were observed predominantly in lower anterior teeth area, especially in lateral incisor and canine region, and many cases of deciduous geminated tooth were observed in upper central incisor region. 3. Congenital missing rates of succedaneous tooth in deciduous fused teeth were 57.1 %, 85.7%, 71.0%, 69.0% in upper right and left central-lateral incisor regions, lower right and left lateral incisor-canine regions, respectively. 4. Prevalence of dental caries was 42.3%, 18.8% and 5.6% in deciduous fused, deciduous geminated and permanent fused tooth, respectively. 5. In classifying of fused and geminated teeth into 9 types, by following appearance such as number of crown, root, pulp chamber and pulp canal of those teeth, it was more favorable that Type Ⅰ(2 crown, 2 root, 2 pulp chamber, 2 pulp canal) in deciduous fused tooth and Type Ⅸ (I crown, 1 root, 1 pulp chamber, 1 pulp canal) in permanent fused tooth, deciduous and permanent geminated tooth.

• 대한치과교정학회지
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• 제28권6호
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• pp.981-989
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• 1998

하악 전치의 위치와 각도, 형태와 근원심 폭경 등은 심미성, 전치부의 적절한 교합, 그리고 치료 후 안정성 측면에서 중요한 의미를 갖는다. 하악 전치가 선천적으로 결손된 경우 수평피개 및 수직피개의 증가, 인접치의 이동, 공극 및 치아 크기 부조화 등 교정적으로 복잡한 문제를 야기할 수 있으므로 하악 전치 결손시 이에 대한 충분한 고려가 필요하다. 하악 전치 결손의 치료계획 수립시 전치의 위치와 각도, 입술 모양, crowding양, 견치와 대구치 관계, 수평 및 수직피개, 전후방적 골격 관계 및 치아크기 비율 등이 고려되어야 하며, 전치부 치아 크기 부조화에 대한 정확한 평가를 위해 diagnostic model set-up을 시행하는 것이 많은 도움이 된다. 본 증례의 두 환자는 모두 하악 전치 2개가 결손되었지만 crowding양, 골격 관계 및 입술 모양, 구치 관계 등이 달랐으며 이에 따른 치료 계획 역시 발치 및 비발치로 상이하였다. 앞으로 두 환자의 치료후 안정 및 유지에 대한 장기간의 관찰이 필요하리라 사료된다.

• Journal of Oral Medicine and Pain
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• 제46권4호
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• pp.125-130
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• 2021

Purpose: The dental age estimation of children is performed using dental maturity. Postmortem missing of the anterior teeth or the distortion of image of the anterior teeth in panoramic radiographs can make it difficult to analyze the development of the anterior teeth. This pilot study was conducted to derive a new age estimation method based only on the developmental stage of mandibular posterior teeth. Methods: This study was conducted using panoramic radiographs of 650 subjects aged 3 to 15 years old. The dental developmental stages of the lower left first premolar, second premolar, first molar and second molar were evaluated according to the Demirjian's criteria. The intra-/inter-observer reliability was evaluated, and multiple linear regression analyses were performed including the developmental stage of each tooth as an independent variable. Results: The intra-/inter-observer reliability was 0.9626 and 0.8877, respectively, and showed very high reproducibility. Multiple linear regression analyses were performed for males and females, and the age calculation table was derived by obtaining the intercept and the coefficient according to the development stage of each tooth. The coefficient of determination (r²) of the age calculation method was 0.9634 for male and 0.9570 for female subjects, and the mean difference between chronological age and estimated dental age was -0.42 and -0.21, respectively. Conclusions: This pilot study evaluated the developmental stages of four lower posterior teeth in the Korean group according to Demirjian's criteria, and derived age estimation method. The accuracy was lower than when more teeth were used, but it will be useful to estimate age of children when the anterior teeth are difficult to accurately analyze.

• 대한치과교정학회지
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• 제24권4호
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• pp.759-772
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• 1994

Orthodontists have experienced the treatment of cases with three lower incisors. Occasionally a lower incisor was either congenitally missing or so seriously damaged by injury or disease that its removal presented the best prospect for the patient. Sometimes the intentional extraction of a lower incisor is needed to produce enhanced functional and esthetic results with minimal orthodontic manipulation. Such cases have unfavorable anterior tooth size discrepancies and present difficulties in achieving good occlusal results. However such difficulties can be overcome by the sensible diagnosis and treatment plan. Three different cases are presented and the conclusions are listed. 1. It is important for orthodontist who tries to treat three lower incisor cases to measure and calculate accurately the degree of deviation of tooth size and morphology and the anterior tooth size ratio. 2. A diagnostic setup model should be made to determine whether the incisor extraction is appropriate and space closure is needed or not. It is the best way to be sure that the occlusal results, including overbite and overjet, will be acceptable and how far the degree of midline deviation is. It also shows the amount of interproximal reduction to achieve an acceptable occlusal result. 3. The class I relationship between the upper canine and the lower one must be obtained to establish the canine rise during eccentric movement by the concept of mutually protective occlusion. It also helps to maintain the stable occlusal result.

• 대한치과교정학회지
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• 제27권4호
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• pp.661-668
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• 1997

치열의 crowding을 해소하는 방법에는 크게 발치, 비발치로 크게 나눌 수 있다. 발치로 교정하는 경우 주로 고려되는 발치대상 치아는 제1, 2 소구치이며 그 다음이 제2 대구치, 하악전치, 제1대구치등 이다. 하악전치의 발치는 소구치 발치가 여의치 않을 때, 선택적으로 사용될 수 있다. case를 잘 선택한다면, 치료시간도 줄일 수 있고, 간편하게, 심미적 및 기능적으로도 좋은 효과를 얻을 수 있다. 아직 이에 대한 국내 연구와 보고가 활발하지 않아 소개하고자 한다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제14권3호
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• pp.185-193
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• 1992

The calcifying odontogenic cyst was identified as a pathological entity by Gorlin & his associates in 1962. This lesion is one of the rarest and most disputable cysts in the oral region. The calcifying odontogenic cyst has variable clinical and radiological features. We review the previous literatures and report 2 cases of calcifying odontogenic cyst at Department of Oral and Maxillofacial Surgery, Kyung-Hee University. The 1st case was as follows. The patient vas 22 year old female. The past dental history revealed extraction of prolonged retained #73 tooth about 15days ago. She complained a painful swelling on the lower anterior teeth area. There were chin and vestibular swelling on the lower anterior teeth area, tenderness and missing of #33 tooth. The radiograph revealed well-demarcated unilocular radiolucency containing radiopaque calcific flecks around impacted #33 tooth. The clinical diagnosis was COC, so surgical enucleation was done. There was no recurrence and COC was confirmed by pathologist. The second case was as follows. The patient was 72 year old male. The past history revealed inactive tuberculosis, bronchial asthma and denture construction. The chief complaint was rapidly growing mass on the lower left anterior edentulous area. The clinical findings were chin swelling protruding mass with surface ulceration, fluctuation and a few bloody fluid in aspiration. The radiograph revealed well-demarcated radiolucency mimiking the residual cyst. The biopsy result was COC. The surgical excision was done, but the lesion was recurred 10 months later. The treatment was surgical excision with aggressive peripheral bone grinding and FTSG form groin area. There was no problem during the postoperative period.

• 대한심미치과학회지
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• 제25권1호
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• pp.25-34
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• 2016

상실한 하악 4전치에서의 치료 계획은 어느 다른 부위보다 수술의 성공률이나 보철치료시 유리한 환경을 지니고 있다고 흔히 생각되는 부위이다. 하지만 하악 전치들의 M-D 사이즈나 crowding으로 인한 공간적 제한, 임시치아 문제, 치조골 흡수로 인해 생기는 심미적인 문제 등 의외로 까다로운 경우가 종종 발생하는 부위기도 한다. 본문에서는 하악 4전치 상실 시의 치료 계확에 대해서 케이스를 통해 알아 보겠다. 하악 4전치 상실시 가능한 옵션들: 하나 혹은 4전치중 일부 상실의 경우나 잔존 치조골의 흡수가 거의 없어 임플란트 위치 관계가 심미적으로 중요하다고 판단되는 경우라면 직경이 작은 임플란트들을 원래 발치와 중앙에 식립(Narrow type 이나 One body mini implant type) 최종 보철물 형태가 Pink porcelain을 포함하는 이미 광범위한 치조골의 흡수가 일어난 경우 즉 임플란트 식립 위치가 덜 중요한 상황이라면 regular size의 임플란트들을 측절치와 중절치의 사이 Interseptal bone위치에 식립 4전치중 하나 혹은 일부가 상실됐고 남아 있는 전치들의 예후가 불량하다고 의심되나 환자가 당장 나머지 전치들의 발치에는 동의하지 않을 때 남아 있는 전치들이 발치 될 때까지의 Tentative restoration로서 Resin Bonded Bridge(Resin Retained Bridge/Resin Bonded Fixed Partial Denture)의 적용.