• 대한치과보철학회지
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• 제31권3호
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• pp.351-384
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• 1993

Complete denture occlusion must be developed to function efficiently and with the least amount of trauma to the supporting tissues. For the preservation of supporting tissues, it is imperative to reduce to a minimum the functional stress induced by dentures. The magnitude of the horizontal component of functional stress contributed by various occlusal teeth forms has not been studied. This study was aimed to investigate the influence of different occlusal teeth forms on the mode of distribution of the stresses in the mandibular tissue, and the displacement of lower dentures during the variant functional movement of mandible for this study three dimensional finite element analysis was used. FEM models were created using commercial software Super Sap for IBM 32 bit computer. The model was composed of 3380 brick elements and 4346 nodes. The results were as follows. 1. The magnitude of stress was similar between two models in centric occlusion, in the case of anatomic model, the stress was concentrated on the buccal side of alveolar ridge beneath the bicuspids. 2. During the protrusive movement, the increasing of stress from the posterior to anterior part of mandible was seen in the case of anatomic model. 3. During the lateral movement, the stress of anatomic model was greater than that of nonanatomic model. 4. The stress of anatomic model was concentrated on the anterior region of residual ridge during the lateral movement. 5. In the case of anatomic model the anterior part of denture was displaced severely at the centric and lateral position, but the denture of nonanatomic model was displaced minutely at the protrusive and lateral position.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제38권1호
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• pp.2-8
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• 2012

Introduction: Auto-tooth bone graft material consists of 55% inorganic hydroxyapatite (HA) and 45% organic substances. Inorganic HA possesses properties of bone in terms of the combining and dissociating of calcium and phosphate. The organic substances include bone morphogenetic protein and proteins which have osteoinduction capacity, as well as the type I collagen identical to that found in alveolar bone. Auto-tooth bone graft material is useful as it supports excellent bone regeneration capacity and minimizes the possibility of foreign body reaction,genetic diseases and disease transmission. Materials and Methods: Implant placement combined with osteoinductive regeneration,preservation of extraction socket, maxillary sinus augmentation, and ridge augmentation using block type,powder type, and block+powder type autobone graft materialwere performed for 250 patients with alveolar bone defect and who visited the Department of Oral and Maxillofacial Surgery, College of Dentistry, Dankook University from September 2009 to August 2011. Results: Clinical assessment: Among the 250 patients of auto-tooth bone graft, clinical assessment was performed for 133 cases of implant placement. The average initial stabilization of placed implants was 74 implant stability quotient (ISQ). Radiological assessment: The average loss of crestal bone in the mandible as measured 6 months on the average after the application of prosthesis load was 0.29 mm, ranging from 0 mm to 3.0 mm. Histological assessment: In the histological assessment, formation of new bone, densified lamellated bone, trabecular bones, osteoblast, and planting fixtures were investigated. Conclusion: Based on these results, we concluded that auto-tooth bone graft material should be researched further as a good bone graft material with osteoconduction and osteoinduction capacities to replace autogenous bone, which has many limitations.

• 대한치과보철학회지
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• 제58권4호
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• pp.306-312
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• 2020

목적: 본 연구의 목적은 골폭이 좁은 치조골을 가진 환자에서 컴퓨터가이드를 이용한 무절개 임플란트 수술로 narrow implant 식립 후 최소 6개월 이상 경과한 환자를 대상으로 임플란트 주변의 골소실 예후를 평가하는데 있다. 재료 및 방법: 2017년 1월 1일부터 2019년 6월 30일 사이에 내원한 환자 중 임플란트 순측을 덮고 있는 치조골의 두께가 0.5 mm에서 1.5 mm 사이인 12명의 환자(12개 narrow implant)에서 CBCT를 이용하여 임플란트 순측에 남아 있는 치조골을 평가하였다. 결과: 임플란트를 덮고있는 순측 치조골의 폭이 아주 얇았지만, 수술 즉시 임시보철물을 장착후 6개월 이상 지난 임플란트의 CBCT를 촬영하여 식립전과 식립후 치조골 변화에 대한 방사선학적 평가에서 임플란트의 순측 치조골이 안정적으로 유지됨이 관찰되었다. 결론: 컴퓨터가이드를 이용한 무절개 임플란트 수술은 전치부에 골폭이 좁은 치조골을 가진 환자에서 임플란트 주변의 골소실을 방지하는데 유리함으로 narrow implant와 함께 유용하게 사용할 수 있는 방법으로 생각된다.

• 대한치과의사협회지
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• 제51권8호
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• pp.459-467
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• 2013

The use of autogenous tooth bone graft material has been commercialized since 2008. Autogenous tooth bone grafts always require that the tooth of the patient be extracted, and thus, the use of graft material are limited in many cases. For solution of limitation in quantity and concurrent use of autogenous tooth bone graft material, the grafting of familial teeth has been suggested. It has the following advantages: the teeth of family members are used as bone graft materials, the genetic composition is identical, and potential genetic and infectious risks can be minimized. Because the teeth of family members are used, a good tissue affinity is obtained, and thus, superior bone generation rates compared to those observed for allogenic or xenogenic bones can be anticipated. We used familial tooth bone-graft materials for alveolar ridge augmentation, socket preservation, and maxillary sinus graft in some cases. In most cases, the impacted third molars of their children were prepared as bone graft material and were used for surgery. In one case, the impacted third molar from the patient's brother was used as bone graft material. We obtained satisfactory result and these cases are reported herein.

• Journal of Periodontal and Implant Science
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• 제50권6호
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• pp.406-417
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• 2020

Purpose: This study investigated whether the placement of ribose cross-linked collagen (RCLC) membranes without primary soft tissue closure predictably resulted in sufficient alveolar ridge preservation in contained and non-contained extraction sockets. Methods: Membranes were positioned across extraction sockets, undermining full-thickness flaps, and the gingival margins were fixed by double-interrupted sutures without crossed horizontal mattress sutures for 1 week. In non-contained sockets, a bone substitute was used to support the membrane within the bony envelope. Radiographs and clinical images obtained 4 months later were analyzed by ImageJ software using non-parametric tests. Results: In 18 patients, 20 extraction sockets healed uneventfully and all sites received standard-diameter implants (4.1, 4.8, or 5.0 mm) without additional bone augmentation. Soft tissues and the muco-gingival border were well maintained. A retrospective analysis of X-rays and clinical photographs showed non-significant shrinkage in the vertical and horizontal dimensions (P=0.575 and P=0.444, respectively). The new bone contained vital bone cells embedded in mineralized tissues. Conclusions: Within the limitations of this pilot study, open healing of RCLC membranes may result in sufficient bone volume for implant placement without additional bone augmentation in contained and non-contained extraction sockets.

• Journal of Periodontal and Implant Science
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• 제37권3호
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• pp.637-646
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• 2007

Implants placed immediately after tooth extraction have been shown to be a successfully predictable treatment modality. Several clinical papers suggest that placing implants immediately after tooth extraction may provide some advantages: reduction of the number of surgical procedures or patient visits, preservation of the dimensions of alveolar ridge, and shortening of the interval between the removal of the tooth and the insertion of the implant supported restoration. In this case report, three patients received single immediate implant placements to replace a maxillary anterior tooth at the time of extraction. As the three cases were somewhat different, treatment protocols had to be modified as follows: Case 1. Immediate implant placement with healing abutment connection. Case 2. Immediate implant placement with immediate provisionalization. Case 3. Immediate implant placement with Guided Bone Regeneration(GBR). Every implant of these cases was placed in proper position buccolingually, mesiodistally and apicocoronally, The procedures following implantation such as immediate provisionalization and GBR were free of problem. Healing of each case was uneventful. In all cases, treatment outcomes were mostly satisfactory and the results maintained during follow-up periods. However, one case (Case 3) showed some papilla loss due to failure in delicate soft tissue handling during surgery. This papilla loss was compromised by prosthetic means. In conclusion, immediate implant placement in the fresh extraction socket can be a valid and successful option of treatment in aesthetic area. Moreover, this treatment protocol seems to maintain the preexisting architecture of soft and hard tissues in most cases.