• 대한치과기공학회지
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• 제26권1호
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• pp.69-76
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• 2004

The objective of this finite element method study was to analyze the stress distribution induced on a supporting bone by 3.75mm, 4.0mm, 5.0mm diameter of dental implant fixture(13mm length). 3-dimensional finite element models of simplified gold alloy crown(7mm height) and dental implant structures(gold cylinder screw, gold cylinder, abutment screw, abutment, fixture and supporting bone(cortical bone, cancellous bone) designs were subjected to a simulated biting force of 100 N which was forced over occlusal plane of gold alloy crown vertically. Maximum von Mises stresses(MPa) under vertical loading were 9.693(3.75mm diameter of fixture), 8.885(4.0mm diameter of fixture), 6.301(5.0mm diameter of fixture) and the highest von Mises stresses of all models were concentrated in the surrounding crestal cortical bone. The wide diameter implant was the good choice for minimizing cortical bone-fixture interface stress.

• The Journal of Advanced Prosthodontics
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• 제6권6호
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• pp.521-527
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• 2014

This case series evaluated the clinical efficacy of autogenous tooth bone graft material (AutoBT) in alveolar ridge preservation of an extraction socket. Thirteen patients who received extraction socket graft using AutoBT followed by delayed implant placements from Nov. 2008 to Aug. 2010 were evaluated. A total of fifteen implants were placed. The primary and secondary stability of the placed implants were an average of 58 ISQ and 77.9 ISQ, respectively. The average amount of crestal bone loss around the implant was 0.05 mm during an average of 22.5 months (from 12 to 34 months) of functional loading. Newly formed tissues were evident from the 3-month specimen. Within the limitations of this case, autogenous tooth bone graft material can be a favorable bone substitute for extraction socket graft due to its good bone remodeling and osteoconductivity.

• 대한치과교정학회지
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• 제32권5호
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• pp.361-373
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• 2002

이번 연구의 목적은 골격성 III급 부정교합자의 악교정 수술 전과 수술 후의 하악전치부 치조골의 형태 변화를 평가하는 것이다 : 하악지 시상골분할절단술만을 시행받은 30명의 성인 골격성 III급 부정교합자를 대상으로 하였다. 초진시와 수술 전과 수술 후 3개월이 경과하였을 때의 측모두부규격방사선 사진을 비교하였다 골격과 하악이부의 계측치를 비교하였으며 이들 사이의 상관성 분석을 시행하여서 다음과 같은 결과를 얻었다. 1. 술전교정후군과 악교정수술후군에서 치료전군에 비해 하악전치부의 순측과 설측의 치조골 높이가 감소하였다. 2. 치조골 기저부의 전후방적인 폭경은 두개안면골격의 수직계측항목과 역상관관계를, IMPA와는 순상관관계를 보였다(P<0.01). 3. 하악이부 계측항목중 하악이부의 장경과 폭경은 두개안면골격과 상관관계를 보이지 않았다. 4. 순측의 치조골 높이와 설측의 치조골 높이는 순상관관계를 나타냈지만(p<0.001), 설측의 치조정의 폭경과는 역상관관계를 보였다(p<0.01). 순측과 설측의 치조정의 폭경은 역상관관계를 보였다(p<0.05). 하악이부의 장경과 폭경은 서로 순상관관계를 보였다(p<0.01). 5. IMPA와 LISA는 순, 설측치조골의 장경과 설측의 치조골 폭경과는 역상관관계를 보였지만, 순측치조골폭경과는 순상관관계를 보였다

• 대한심미치과학회지
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• 제8권1호
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• pp.28-35
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• 1999

The preservation of a healthy periodontal attachment is the most significant factor in the long-term prognosis of a restored tooth. The 'Biologic Width' is composed of the connective tissue attachment and the epithelial attachment in the dentogingival junction. The violation of the biologic width may result in a progressive inflammatory process and crestal bone loss. So a careful soft tissue management is needed to preserve it for the gingival health and an esthetic restoration. The following clinical cases show the five different situations of the violation of the biologic width and their management.

• 대한치주과학회:학술대회논문집
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• 대한치주과학회 2007년도 제47회 종합학술대회 연제초록
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• pp.186-187
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• 2007

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제48권4호
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• pp.245-245
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• 2022

• Maxillofacial Plastic and Reconstructive Surgery
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• 제34권6호
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• pp.440-448
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• 2012

Purpose: The purpose of this study was to evaluate marginal bone loss of the alveolar crest on implants with or without guided bone regeneration and variables that have influenced. Methods: The clinical evaluation were performed for survival rate and marginal bone loss of 161 endosseous implants installed with guided bone regeneration (GBR) in 83 patients from September 2009 to October 2010 in relation to sex and age of patients, position of implant, implant system, length and diameter of implant. Study group (n=42) implant with GBR procedure, control group (n=41) implant without GBR technique. Simultaneous GBR approach using resorbable membranes combined with autogenous bone graft or freeze-dried bone allograft or combination. Radiographic examinations were conducted at healing abutment connection and latest visit. Marginal bone level was measured. Results: Mean marginal bone loss was 0.73 mm in study group, 0.63 mm in control group. Implants in maxillary anterior area (1.21 mm) were statistically significant in study group (P<0.05), maxillary posterior area (0.81 mm) in control group (P<0.05). Mean marginal bone loss 1.47 mm for implants with diameter 3.4 mm, 0.83 mm for implants of control group with diameter 4.0 mm (P<0.05). Some graft materials showed an increased marginal bone loss but no statistically significant influence of sex, implant type or length. Conclusion: According to these findings, this study demonstrated the amount of marginal bone loss around implant has maintained a relative stable during follow-up periods. We conclude that implants with GBR had similar survival rate and crestal bone level compared with implants in native bone.

• Journal of Periodontal and Implant Science
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• 제37권3호
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• pp.647-653
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• 2007

Rapid crestal bone resorption following maxillary tooth loss is further accentuated in the posterior regions because of pneumatization and enlargement of the maxillary sinuses. A treatment rationale that allows preservation and augmentation of vertical available bone at the time of posterior maxil-lary tooth extraction may offer numerous therapeutic benefits which are more short courses of ther-apy and no needs of additional surgical augmentation. The present study comprised 3 patients who had 4 posterior maxillary teeth with no evident bone between the tooth apex and sinus floor, as estimated through preoperative radiographic analysis. Sinus floor augmentation at the time of tooth extraction was chosen for the ltreatment of these patients. After the tooth was carefully extracted, the empty alveolus was thoroughly debrided and a trephine approach was performed. Particulated autogenous bone was gently pushed beyond the empty alveolus to elevate the sinus membrane using an osteotome. The distance between bone crest and si-nus floor was radiographically estimated 4 months after the first procedure. Another procedure was then carried out to place the implants of 11 mm length without another augmentation procedure. All implant were clinically stable, with no sign of infection. The presented surgical procedure performed at the time of extraction of posterior maxillary teeth in close proximity to the sinus floor allowed placement of implants of proper length.

• 구강회복응용과학지
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• 제18권2호
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• pp.127-144
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• 2002

There is an increasing appreciation of the vital role that biomechanics play in the performance of oral implant. The aim of this article is to provide some basic principles that will allow a clinician to formulate a biomechanically valid treatment plan. However, at this point in the history of oral implantology, the clinician should realize that we do not know enough to provide absolute biomechanical rules that will guarantee success of all implants in all situations. To examine the biomechanical questions, one must begin with an analysis of the distribution of biting forcess to implants. Related topics, such as stress transfer to surrounding tissues and interrelationships between bone biology and mechanical loading are major subjects, deserving a separate discussion. Once rigid fixation, angulation, crestal bone level, contour, and gingival health are achieved, stress beyond physiologic limits is the primary cause of initial bone loss around implants. The restoring dentist has specific responsibilities to reduce overload to the bone-implant interface. These include proper diagnosis, leading to a treatment plan designed with adequate retention and form, and progressive loading to improve the amount and density of bone and further reduce the risk of stress beyond physiologic limits. The major remaining factor is the development of occlusal concept in harmony with the rest of the stomagnetic system.

• 구강회복응용과학지
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• 제22권1호
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• pp.55-74
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• 2006

The external contour of an implant can have significant effects on the load transfer characteristics and may result in different bone failure rates for different implant system. The purpose of this study was to investigate the effects of crest module shape and occlusal load direction on bone failure modes of five commercially available dental implant systems. Five different implant systems with internal connection; ITI (Model 1), Astra (Model 2), Bicon (Model 3), Friadent (Model 4), and Paragon (Model 5), comparable in size, but different in thread profile and cest module shapes, were compared using the finite element method. Conclusively, in the internal connection system of the implant-abutment connection methods, the stress-induced pattern at the supporting bone according to the abutment connection form had differenence among them, and implants with narrowing crestal module cross-sections at the top of the cortical bone created more favorable load transfer characteristics in this region. But it is considered that the future study is necessary about how this difference in the magnitude of the stress have an effect on the practical clinic.