• Maxillofacial Plastic and Reconstructive Surgery
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• 제31권4호
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• pp.334-338
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• 2009

Supernumerary teeth are extra teeth or tooth-like structures which may have either erupted or unerupted in addition to the 20 deciduous teeth and the 32 permanent teeth. Clinicians sometimes confront unerupted supernumerary teeth where implants would be placed. Many clinicians consider immediate placement of implant into an extracted socket as an effective technique compared to the conventional method of waiting several months for bone healing, because of the advantages such as reduction of treatment period, preservation of alveolar bone and soft tissue, etc. We could hardly find the case of immediate placement of implant after extraction of impacted supernumerary teeth and permanent teeth together. Therefore we report the case of immediate implantation following extraction of impacted supernumerary teeth and poor periodontal conditioned permanent teeth.

• Journal of Periodontal and Implant Science
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• 제47권1호
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• pp.51-63
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• 2017

Purpose: Following tooth extraction, alveolar ridge preservation (ARP) can maintain the dimensions of ridge height and width. Although previous studies have demonstrated the effects of ARP, few if any studies have investigated the compressive force applied during grafting. The aim of this study was to determine the effects of different compressive forces on the graft materials during ARP. Methods: After tooth extraction, sockets were filled with deproteinized bovine bone mineral with 10% porcine collagen and covered by a resorbable collagen membrane in a double-layered fashion. The graft materials were compressed using a force of 5 N in the test group (n=12) and a force of 30 N in the control group (n=12). A hidden X suture was performed to secure the graft without primary closure. Cone-beam computed tomography (CBCT) was performed immediately after grafting and 4 months later, just before implant surgery. Tissue samples were retrieved using a trephine bur from the grafted sites during implant surgery for histologic and histomorphometric evaluations. Periotest values (PTVs) were measured to assess the initial stability of the dental implants. Results: Four patients dropped out from the control group and 20 patients finished the study. Both groups healed without any complications. The CBCT measurements showed that the ridge volume was comparably preserved vertically and horizontally in both groups (P>0.05). Histomorphometric analysis demonstrated that the ratio of new bone formation was significantly greater in the test group (P<0.05). The PTVs showed no significant differences between the 2 groups (P>0.05). Conclusions: The application of a greater compressive force on biomaterials during ARP significantly enhanced new bone formation while preserving the horizontal and vertical dimensions of the alveolar ridge. Further studies are required to identity the optimal compressive force for ARP.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제39권
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• pp.29.1-29.5
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• 2017

Background: The surgical extraction of the third molar is the most frequently encountered procedure in oral and maxillofacial surgery and is related with a variety of complications. This study examined the efficacy of intentional partial odontectomy (IPO) in the third molars which have no periapical lesions and are located near important anatomical structures such as inferior alveolar nerve. Methods: Seven patients (four males, three females, $39.1{\pm}11.6years$), who received IPO to reduce the risk of inferior alveolar nerve injury (IANI), were followed long-term. The treated teeth were horizontally impacted third molars in the mandibular left (n = 5) or mandibular right (n = 4) areas and were all ankylosed with the surrounding alveolar bone. During the IPO, the bone around the crown was removed to expose the crown, and then the tooth was resected at cement-enamel junction (CEJ). Any secondary trauma to the healthy root was minimized and remained intact after primary suture. Results: The mean follow-up time was $63.2{\pm}29.8months$, and all sites showed good bone healing after the crown removal. Also, sensory abnormality was not found in any patients after IPO. In one patient, the bone fragments erupted 4 months after IPO. In other patient, an implant placed on second molar site adjacent to the third molar that received IPO was explanted about 2 years after the patient's persistent discomfort. Conclusions: In case where high risk of IANI exists, IPO may be chosen alternatively to surgical extraction to reduce the risk of nerve damage.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제45권6호
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• pp.309-315
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• 2019

Objectives: The aim of this study was to evaluate the validity of the existing classification and difficulty index of impacted mandibular third molars in clinical situations and propose a more practical classification system. Materials and Methods: This study included 204 impacted mandibular third molars in 154 patients; panoramic x-ray images were obtained before tooth extraction. Factors including age, sex, and pattern of impaction were investigated. All impacted third molars were classified and scored for spatial relationship (1-5 points), depth (1-4 points), and ramus relationship (1-3 points). All variables were measured twice by the same observer at a minimum interval of one month. Finally, the difficulty index was defined based on the total points scored as slightly difficult (3-4 points), moderately difficult (5-7 points), very difficult (8-10 points), and extremely difficult (11-12 points). Results: The strength of agreement of the total points scored and difficulty index were 0.855 and 0.746, respectively. Most cases were classified as moderately difficult (73.0%). Although only 13 out of 204 cases (6.4%) were classified as extremely difficult, patients classified as extremely difficult were the oldest (P<0.05). Conclusion: For difficulty classification, the authors propose one more difficult category beyond the existing three-step difficulty index: the clinician should consider the patient's age in the difficulty index evaluation.

• Journal of Periodontal and Implant Science
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• 제54권2호
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• pp.108-121
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• 2024

Purpose: The aim of this study was to compare changes in soft and hard tissue and the histologic composition following early implant placement in sites with alveolar ridge preservation or spontaneous healing (SH), as well as implant performance up to 1 year after crown insertion. Methods: Thirty-five patients with either intact buccal bone plates or dehiscence of up to 50% following single-tooth extraction of incisors, canines, or premolars were included in the study. They were randomly assigned to undergo one of three procedures: deproteinized bovine bone mineral with 10% collagen (DBBM-C) covered by a collagen matrix (DBBM-C/CM), DBBM-C alone, or SH. At 8 weeks, implant placement was carried out, and cone-beam computed tomography scans and impressions were obtained for profilometric analysis. Patients were followed up after the final crown insertion and again at 1 year post-procedure. Results: Within the first 8 weeks following tooth extraction, the median height of the buccal soft tissue contour changed by -2.11 mm for the DBBM-C/CM group, -1.62 mm for the DBBM-C group, and -1.93 mm for the SH group. The corresponding height of the buccal mineralized tissue changed by -0.27 mm for the DBBM-C/CM group, -2.73 mm for the DBBM-C group, and -1.48 mm for the SH group. The median contour changes between crown insertion and 1 year were -0.19 mm in the DBBM-C/CM group, -0.09 mm in the DBBM-C group, and -0.29 mm in the SH group. Conclusions: Major vertical and horizontal ridge contour changes occurred, irrespective of the treatment modality, up to 8 weeks following tooth extraction. The DBBM-C/CM preserved more mineralized tissue throughout this period, despite a substantial reduction in the overall contour. All 3 protocols led to stable tissues for up to 1 year.

• 대한소아치과학회지
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• 제35권4호
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• pp.750-756
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• 2008

과잉치는 상악 정중부에서 주로 발견되며, 과잉치의 발생 기전은 유전적 또는 환경적 원인에 의하여 치배 형성기 동안에 정상 치판의 비정상적 증식에 의한 것으로 보고되었다. 과잉치로 인한 합병증으로는 인접 영구치의 맹출 장애와 전위, 회전, 정중이개, 비강으로의 맹출, 낭종 형성 등 이 있다. 과잉치를 외과적으로 발거하기 위한 시기에 대해서는 논란이 되고 있다. 인접치의 배열과 맹출 장애, 전위를 야기할 수 있기 때문에 조기에 발거하자는 견해와 어린이의 행동 조절 및 인접 영구치의 치근 형성 정도를 고려하여 $8{\sim}10$세 이후에 발거 하자는 견해가 있다. 후자와 같이 외과적 발거 시기를 연기할 경우, 역위 및 수평 매복된 과잉치는 악골 내에서 비강 또는 경구개, 소구치 부위 등으로 이동할 수 있으며, 과잉치의 이동과 전상악골의 수직고경 증가로 인하여 외과적 발거 시 난이도가 높아질 수 있다. 따라서, 역위 및 수평 매복된 과잉치의 외과적 발거 시기를 결정하기 위하여 연기하는 경우에 과잉치의 악골 내 이동을 고려해야 한다. 이 증례는 상악 정중부에 역위 매복된 과잉치가 있어서 내원한 $6{\sim}7$세의 어린이에서 과잉치의 외과적 발거 시기를 결정하기 위하여 주기적인 방사선 학적 검사로 관찰하던 중에 $2{\sim}3$년 후 과잉치 위치가 악골 내에서 초진 시 위치로부터 이동된 경우로 이를 보고하는 바이다.

• 대한치과교정학회지
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• 제35권1호
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• pp.23-34
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• 2005

본 연구에서는 III급 수술-교정 치료 방법에 영향을 미치는 치열 상의 요소를 파악함으로써 술전 교정시 상악 소구치 발치와 비발치의 판단에 필요한 임상적 정보를 얻고자 골격성 III급 부정교합 환자의 수술-교정 치료시 흔히 선택되는 상악 제1소구치 발치로 치료된 군과 비발치로 치료된 군 간의 치료전/후 상/하악 개별 치아 이동 양상과 치열궁 폭경의 변화 양상을 비교 분석하였다 이를 위하여 비발치로 III급 수술-교정 치료를 마친 환자 (24명) 와 술전교정 치료시 상악 제1소구치가 발치된 환자 (31 명)의 치료 전/후 모형 상에서 개개 치아의 근원심/협설측 각도 변화와 상/하 치열궁 폭경의 변화를 측정한 후, 두 군 사이의 교정적 치아 이동 양상을 비교 분석한 후 상/하 치열궁의 조화를 이루는데 필요한 치열궁 폭경의 변화와 이에 기여하는 치아 변위와의 관계를 분석하기 위하여 상관 분석과 회귀 분석을 시행한 결과 발치 군은 비발치 군에 비하여 상악 치열궁 폭경의 감소가 컸으며 이는 상악 구치의 inclination 감소에 크게 영향 받은 것으로 관찰되었다. 하악 치열에서는 inclination의 증가와 폭경의 증가가 있었으나, 비발치/발치군간의 차이는 유의하지 않았다 본 연구의 결과 결론적으로 III급 수술-교정 치료시 술전 상악 소구치 발치는 상악 구치부 치열궁 폭경의 감소에 크게 영향을 미치므로, 상악 소구치 발치에 대한 판단은 상/하악 치열궁의 폭경 및 구치부 경사도 문제와 연계하여 고려해야 할 사항으로 생각되었다.

• Journal of Yeungnam Medical Science
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• 제20권1호
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• pp.45-52
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• 2003

Background: Immediate implant placement has become an acceptable treatment for the edentulous area. The advantages of the immediate implant placement include considerable decrease in time from tooth extraction to placement of the finial prosthesis, fewer surgical procedures, and better acceptance of the overall treatment plans. But the success is dependent on the quantity and quality of the extraction socket. The purpose of this study is to evaluate the success of the immediate implant placement. Materials and Methods: Twenty-one sites in 16 patients were selected for the evaluation of the immediate implant placement. All of the cases were followed using clinical and radiographic examinations. Criteria of success were the absence of peri-implant radiolucency, mobility, and persistent pain or sign of infection. Results: Of the 21 implants, 13 implants have been succeeded. Of the 13 implants, 10 implants were replaced for the periodontal disease and 3 implants were replaced for the trauma. Conclusion: The criteria of the success in immediate implant placement are as follows. 1) Implants placed into fresh extraction sockets have a high rate of survival. 2) Implant should be placed as close as possible to the alveolar crest. 3) Implant placed into available bone beyond the apex have a high success rate.

• Journal of Periodontal and Implant Science
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• 제45권6호
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• pp.216-222
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• 2015

Purpose: After extraction, the alveolar bone tends to undergo atrophy in three-dimensions. The amount of alveolar bone loss in the horizontal dimension has been reported to be greater than the amount of bone loss in the vertical dimension, and is most pronounced in the buccal aspect. The aim of this study was to monitor the predictive alveolar bone level following the extraction of anterior teeth seriously involved with advanced chronic periodontitis. Methods: This study included 25 patients with advanced chronic periodontitis, whose maxillary anterior teeth had been extracted due to extensive attachment loss more than one year before the study. Periapical radiographs were analyzed to assess the vertical level of alveolar bone surrounding the edentulous area. An imaginary line connecting the mesial and the distal ends of the alveolar crest facing the adjacent tooth was arbitrarily created. Several representative coordinates were established in the horizontal direction, and the vertical distance from the imaginary line to the alveolar crest was measured at each coordinate for each patient using image analysis software. Regression functions predicting the vertical level of the alveolar bone in the maxillary anterior edentulous area were identified for each patient. Results: The regression functions demonstrated a tendency to converge to parabolic shapes. The predicted maximum distance between the imaginary line and the alveolar bone calculated using the regression function was $1.43{\pm}0.65mm$. No significant differences were found between the expected and actual maximum distances. Likewise, the predicted and actual maximum horizontal distances did not show any significant differences. The distance from the alveolar bone crest to the imaginary lines was not influenced by the mesio-distal spans of the edentulous area. Conclusions: After extraction, the vertical level of the alveolar ridge increased to become closer to the reference line connecting the mesial and distal alveolar crests.

• Journal of Periodontal and Implant Science
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• 제49권3호
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• pp.158-170
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• 2019

Purpose: This study investigated the association between health status and tooth loss based on data from the National Health Insurance Service-Health Examinee Cohort in 2002-2015. Methods: Multivariate Cox proportional hazards regression analyses were applied to a longitudinal retrospective database, which was updated and newly released in 2018, to assess the association between health status and tooth loss while adjusting for potential confounders among sociodemographic and economic factors (sex, age, household income, insurance, and presence of disability), general and oral health status (body mass index [BMI], smoking and drinking status, periodic dental visits and scaling, and brushing before sleep), and comorbid disease (hypertension, diabetes mellitus [DM], and Charlson comorbidity index [CCI]). Results: Among 514,866 participants from a South Korean population, 234,247 (45.5%) participants satisfying the inclusion criteria were analyzed. In the adjusted multivariate analysis, sex, age, household income, insurance, presence of disability, BMI, smoking and drinking status, periodic scaling, tooth brushing before sleep, DM, and CCI showed statistically significant associations with the loss of at least 1 tooth. The risk of experiencing a loss of ${\geq}4$ teeth was associated with an increase in age (in those 50-59 years of age: hazard ratio [HR], 1.98; 95% confidence interval [CI], 1.93-2.03; in those 60-69 years of age: HR, 2.93; 95% CI, 2.85-3.02; and in those 70-79 years of age: HR, 2.93; 95%, CI 2.81-3.05), smoking (HR, 1.69; 95% CI, 1.65-1.73), and DM (HR, 1.43; 95% CI, 1.38-1.48). Conclusions: The results of this study showed that the risk of experiencing tooth loss was related to multiple determinants. DM and smoking were especially significantly associated with tooth loss.