• 대한치과보철학회지
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• 제45권5호
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• pp.633-643
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• 2007

Statement of problem: Recently there are on an increasing trend of using implants-especially in edentulous mandible of severly alveolar bone recessed. Purpose: The aim of this study was to analyze the displacement and stress distribution of various mandibular implant-retained overdenture models supported by two implants in interforaminal region under the occlusion scheme load. Material and method: FEA models were made by the 3D scanning of the edentulous mandibular dentiform. The three models were named as Model M1, M2, and M3 accord ing to the position of implants: M1, Lt. incisor area, M2, Canine area, and M3, 1st Premolar area. Inter-implant angulation model was named as M4. Conventional complete denture was named M5 and used as a control group. Ball implant and Gold matrice were used as a retentive anchors. The occlusion type loads were applied horizontally over each tooth. Results: 1. In mandibular implant retained overdenture Canine Protected Occlusion type load resulted in higher levels of stress to the implants and female matrices than other types of loads. 2. The overdenture model M1, with implants in lateral incisor areas resulted in lower stress concentration to the implants and female matrices than other models. 3. In mandibular implant retained overdenture the stresses of the implant and female matrice were lower in mesially inclined implant than these of parallel installed implant. Conclusion: Lateral incisor areas could be the best site for the implants in mandibular implant-retained overdenture. The mandibular implant retained overdenture models mentioned above showed to the lowest stress to the implants and female matrices.

• The Journal of Advanced Prosthodontics
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• 제8권2호
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• pp.85-93
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• 2016

PURPOSE. The purpose of this study was to determine the effect of anchorage systems and palatal coverage of denture base on load transfer in maxillary implant-retained overdenture. MATERIALS AND METHODS. Maxillary implant-retained overdentures with 4 implants placed in the anterior region of edentulous maxilla were converted into a 3-D numerical model, and stress distribution patterns in implant supporting bone in the case of unilateral vertical loading on maxillary right first molar were compared with each other depending on various types of anchorage system and palatal coverage extent of denture base using three-dimensional finite element analysis. RESULTS. In all experimental models, the highest stress was concentrated on the most distal implant and implant supporting bone on loaded side. The stress at the most distal implant-supporting bone was concentrated on the cortical bone. In all anchorage system without palatal coverage of denture base, higher stresses were concentrated on the most distal implant and implant supporting bone on loaded side. CONCLUSION. It could be suggested that when making maxillary implant retained overdenture, using Hader bar instead of milled bar and full palatal coverage rather than partial palatal coverage are more beneficial in distributing the stress that is applied on implant supporting bone.

• 구강회복응용과학지
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• 제33권4호
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• pp.321-328
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• 2017

무치악은 총의치나 임플란트 보철물로 수복이 가능하며 임플란트를 이용한 피개의치는 총의치보다 유지와 안정이 우수하고, 임플란트 고정성 보철물에 비해 저렴하고 심미적이다. CM $LOC^{(R)}$ $Pekkton^{(R)}$ 어태치먼트는 여자부가 poly-ether-ketone-ketone으로 마모저항성이 뛰어나다. 한편, SR Ivocap system은 가압주사성형법으로 의치의 수직고경 변화가 적고 강도가 우수하다. 본 증례에서 상악은 4개의 임플란트 식립 후 CM $LOC^{(R)}$ $Pekkton^{(R)}$ 어태치먼트와 SR Ivocap system을 이용한 임플란트 유지 피개의치를, 하악은 가철성 국소의치를 제작하였고 심미적 및 기능적으로 만족스러운 결과를 얻었기에 이를 보고하는 바이다.

• 대한치과보철학회지
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• 제41권6호
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• pp.747-761
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• 2003

Statement of problem. The proper materials of attachments for implant retained overdenture are unknown, such as the correlation between retention and abrasion, as well as the types of materials that are suitable for patrix and for matrix individually. Purpose of this study. The aim of this study was to select a proper clinical attachment system for a successful treatment as well as patient satisfaction. Methods. Retention and abrasion of 14 commercial attachments were measured during 15,000 removes. Results. A retentive part (matrix) which requires elasticity has to be made of gold while the patrix part which does not require elasticity has to be made of titanium. This gold matrix / titanium patrix combination showed the most retentive force and the least retention loss.

• The Journal of Advanced Prosthodontics
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• 제5권3호
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• pp.333-340
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• 2013

PURPOSE. This study was accomplished to assess the biomechanical state of different retaining methods of bar implant-overdenture. MATERIALS AND METHODS. Two 3D finite element models were designed. The first model included implant overdenture retained by Hader-clip attachment, while the second model included two extracoronal resilient attachment (ERA) studs added distally to Hader splint bar. A non-linear frictional contact type was assumed between overdentures and mucosa to represent sliding and rotational movements among different attachment components. A 200 N was applied at the molar region unilaterally and perpendicular to the occlusal plane. Additionally, the mandible was restrained at their ramus ends. The maximum equivalent stress and strain (von Mises) were recorded and analyzed at the bone-implant interface level. RESULTS. The values of von Mises stress and strain of the first model at bone-implant interface were higher than their counterparts of the second model. Stress concentration and high value of strain were recognized surrounding implant of the unloaded side in both models. CONCLUSION. There were different patterns of stress-strain distribution at bone-implant interface between the studied attachment designs. Hader bar-clip attachment showed better biomechanical behavior than adding ERA studs distal to hader bar.

• 구강회복응용과학지
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• 제33권1호
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• pp.55-62
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• 2017

무치악 환자를 수복할 때 임플란트 피개의치를 이용한 치료법은 전통적인 총의치의 문제점인 저작시 동통, 의치의 부족한 유지와 안정을 포함하는 기능저하 문제 등을 해결할 수 있는 방법이다. $Locator^{(R)}$ (Zest Anchors LLC, Espandido, USA) 어태치먼트는 임플란트 피개의치에 사용되는 어태치먼트 중 수직적으로 필요한 공간이 가장 적고, 나일론 부품에 따라 유지력 조절이 용이하다. 하지만 Ball이나 Bar에 비해 기능시 부품의 마모로 유지력이 빠르게 감소하는 특징이 있어 가급적 임플란트 간 각도가 최소가 되도록 식립하려는 노력이 필요하다.

• 대한치과보철학회지
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• 제46권2호
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• pp.193-200
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• 2008

임플랜트 고정체의 표면처리 기술의 발달에 기인하여 골유착의 성공률이 좋아지고 있으며 임플랜트를 이용하는 보철물의 형태와 임상 술 식도 다양하게 발전되고 있다. 상악의 임플랜트 피개의치는 아직 표준화된 치료법에 대한 의견이 분분하다. 본 연구는 상악 무치악의 치료를 위하여 해부학적인 요소와 생역학적인 요소를 고려하여 양측 견치부 또는 소구치부위에 2개의 임플랜트를 식립할 때의 응력분포를 삼차원 유한요소분석을 이용하여 관찰하고자 하여 다음과 같은 결론을 얻었다. 1. 임플랜트를 양측 견치 부위에 식립한 모형에서 부하가 가해지는 우측의 임플랜트의 원심면에 최대 응력이 집중되었다. 2. 임플랜트를 양측 제2소구치 부위에 식립한 모형에서 임플랜트 주위의 응력 분포는 부하지점의 거리와 상관없이 고르게 나타났다. 3. 치조골에 발생하는 응력 분포의 관찰 결과, 임플랜트가 양측 제2소구치 부위에 식립된 모형이 양측 견치부위에 식립된 모형보다 고르게 나타났다. 이상의 결과로 볼 때, 상악 피개의치를 위한 임플랜트 식립 위치는 견치 부위에서보다 제2소구치 부위가 구강점막, 주위 골과 임플랜트에 전달되는 응력의 분포에 유리한 것으로 사료된다.

• 구강회복응용과학지
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• 제24권4호
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• pp.351-359
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• 2008

임플란트의 도입으로 악골이 흡수된 무치악 환자의 보철 치료에 획기적인 변화가 가능해졌다. 특히 하악 무치악 환자의 경우 2개의 임플란트에 의해 유지를 얻는 피개의치가 일반적인 총의치의 대안으로 자리잡았으며 첫 번째로 고려되어야 할 치료 방법으로 받아들여지고 있다. 본 증례는 상하악 완전 무치악 환자로서 상악에는 일반적인 총의치, 하악에는 2개의 임플란트를 식립하고 $Locator^{(R)}$ Attachment를 사용하여 수복한 임상과정 및 결과에 관하여 보고하고자 한다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제45권4호
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• pp.199-206
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• 2019

Objectives: In mandibular edentulism, the treatment option with a two-interforaminal implant-retained bridge and a removable partial denture is rarely evaluated in literature. The aim of this in vitro study was to evaluate the stress distribution of this treatment option by comparing it with traditional treatment options with interforaminal implants in the edentulous mandible. Materials and Methods: Two interforaminal implants were placed in a formalin-fixed cadaver mandible, and overdentures with three different types of attachments were fabricated: (1) two ball attachments and an overdenture, (2) a Dolder bar and an overdenture, and (3) screw-retained two-implant inter-canine porcelain fused to a metal bridge and an implant-assisted removable denture (IARD) with precision attachments. Three biting conditions were generated for each denture type, and the strains were documented under vertical loading of 100 N. Results: The calculated strain values from measured strains in all measurement sites and loading conditions for the screw-retained two-implant intercanine porcelain fused to a metal bridge and a cast framework partial denture with precision attachments situation were lower than in the other scenarios (P<0.05). Conclusion: Within the limitations of the present study, it can be concluded that an IARD may be a reasonable and valuable alternative to ball attachments or a bar in two interforaminal implants, especially when the patients prefer to be able to show their teeth even when they take out their removable dentures.

• 대한치과보철학회지
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• 제45권6호
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• pp.760-768
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• 2007

Statement of problem. Conventional denture treatment for totally edentulous patients is associated with a variety of functional and psychosocial problems. The placement of implants in the anterior region of the maxilla and mandible and the fabrication of an implant-retained overdenture might solve these problems. Purpose. This study compared the marginal bone loss around the implant and evaluated the implant survival rate and complications in patients treated with overdentures retained by implants for 2 years. Material and methods. Patients who had received implant-retained overdentures using a Dolder bar at Samsung Medical Center from January 1999 to June 2005 and had participated in the annual recall programs for two years were selected for this study. A total of 18 patients and 56 $Br{\aa}ne-mark\;system^{(R)}$ implants were used, and their data were reviewed. Evaluations of the survival rate, bone quality, marginal bone loss, and complications were performed. The data on the Dolder bar length and clip length were measured. The change in marginal bone loss and the correlation between the marginal bone loss and bar length, clip length, or bone quality were investigated. Results. Implants placed in this study showed a 100% survival rate. The average annual bone loss was 1.12mm in the first year and 0.27mm in the second year in the maxilla, and 0.58mm in the first year and 0.22mm in the second year in the mandible. The marginal bone loss in the maxilla showed no significant association with those in the mandible. (P>.05). There was no significant difference in marginal bone loss around implants between the first and second year. (P>.05) There was no statistically significant relationship (P>.05) between the marginal bone loss and bone quality, clip length, or Dolder bar length. The Dolder bar length showed a high correlation with the clip length. (P<.05) Various complications were noted. Conclusion. These results confirmed the favorable outcome for patients treated with implant-retained overdentures.