• 대한치과보철학회지
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• 제43권6호
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• pp.717-726
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• 2005

Statement of problem. One of the common problems of provisional crown and fixed partial denture materials is that when they are subjected to constant loads for a long period of time, they exhibit a dimensional change (creep). Purpose. The aim of this study was to investigate the viscoelastic behaviour of polymer-based provisional crown and fixed partial denture materials with time at constant compressive load. Material and methods. Three dimethacrylate-based materials (Protemp 3 Garant, Temphase, Luxatemp) and one monomethacrylate-based material (Trim) were selected. Dimensional changes of the specimens were recorded by a LVDT to evaluate their viscoelastic behavior and creep strain. For all specimens, two loading procedures were used. At first, static compressive stress of 4 MPa was applied for 30 minutes and followed by 1 hour of strain recovery. Then, after 24 hours of water storage, the specimens were loaded again. The creep values between materials were statistically analyzed using one-way ANOVA and multiple comparison $Scheff\acute{e}$ test. Independent samples t-test was also used to identify the difference of creep strain between first and secondary loading conditions at the significance level of 0.05. Results. Following application of the first loading, Trim showed the highest maximum creep strain (32.7%) followed by Luxatemp, Protemp 3 Garant and Temphase, with values of 3.78%, 2.86% and 1.77%, respectively. Trim was significantly different from other materials (P<0.05), while there were no significant differences among Luxatemp, Protemp 3 Garant and Temphase (P>0.05). The highest recovery and permanent set of Trim, were significantly different from those of others (P<0.05). At the secondary loading of the dimethacrylate-based materials, creep deformation, recovery and permanent set decreased and the percentage of recovery increased, while in Trim, all values of the measurements increased. This result showed that the secondary loading at 24 hours produced a significant creep magnitude. Conclusion. The dimethacrylate-based provisional crown and fixed partial denture materials showed significantly higher creep resistance and lower deformation than the monomethacrylate-based material. Thus, monomethacrylate-based materials should not be used in long-term stress-bearing situations.

• 대한치과보철학회지
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• 제46권6호
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• pp.639-643
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• 2008

STATEMENT OF PROBLEM: The degree of conversion may influence the ultimate mechanical and physical properties of provisional crown and fixed partial denture materials. The high levels of the unreacted residual monomer may cause deleterious effect on the properties. PURPOSE: The purpose of this study was to measure the degree of conversion of bis-acrylic based provisional crown and fixed partial denture materials by using an infrared spectroscopic method. MATERIAL AND METHODS: Chemically activated three bis-acrylic based provisional crown and fixed partial denture materials, LuxaTemp [DMG, Hamburg, Germany], fast set TemPhase [Kerr, Orange, CA, USA] and Protemp 3 Garant [3M-ESPE, St Paul, MN, USA], were investigated by Fourier transform infrared spectrometry (FTIR). The FTIR spectra of the materials tested were immediately obtained after mixing. The specimens were stored under dry conditions and at $23^{\circ}C$ for 24 hours, and then the spectra of the materials were also obtained. The degree of conversion (%) was calculated from the spectrum of the absorbance between the aliphatic double bond at 1637 $cm^{-1}$ and the aromatic double bond at 1608 $cm^{-1}$ using the baseline method. The data were statistically analyzed using one-way ANOVA and the multiple comparison Scheffe test at the significance level of 0.05. RESULTS: The mean value and standard deviation of the degree of conversion were 52.5 % ${\pm}$ 1.1 %, 50.3 % ${\pm}$ 0.8 %, and 42.3 % ${\pm}$ 4.9 % for LuxaTemp, Protemp 3 Garant and fast set TemPhase, respectively. There was no significant difference between LuxaTemp and Protemp 3 Garant, whereas there was a statistically difference between Protemp 3 Garant and fast set TemPhase, and LuxaTemp and fast set TemPhase (P < .05). CONCLUSION: The degree of conversion of fast set TemPhase was significantly lower than those of the others. The degree of conversion may be correlated with the rate of polymerization.

• 대한치과보철학회지
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• 제61권2호
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• pp.135-142
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• 2023

일명 '메릴랜드 브릿지'로 불리는 Resin-bonded fixed partial denture (RBFPD)는 전치부 결손부위를 수복하는데 있어 침습범위를 최소화하는 보존적 보철치료로 잘 정립되어 있다. 하지만 RBFPD의 여러 이점에도 불구하고 높은 탈락률, 비심미성, 지지체 파절 등으로 인해 보편적인 치료방법으로 선택되지는 못하였다. 최근 치과 재료의 발달과 함께 지르코니아가 RBFPD의 새로운 재료로 도입되면서 강도와 심미성이 개선된 전치부 RBFPD의 적용에 적합한 재료로 평가받고 있다. 본 증례는 상악 좌측 측절치를 상실한 환자에서 지르코니아 RBFPD를 수복한 증례로, 전치부에서 비침습적이며 심미적인 보철물을 이용하여 치아상실부위를 수복하였고, 환자와 술자 모두 만족하는 결과를 얻었기에 본 증례를 보고하는 바이다.

• 대한치과보철학회지
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• 제42권2호
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• pp.125-132
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• 2004

Statements of problem: All ceramic fixed partial denture cores can be made by the slip casting method and the advanced alumina tape method. The fracture resistance of these core connector areas is relatively low. Purpose: The purpose of this study is to standardize the appropriate volumetric figure and location of the connectors in the alumina core fabricated in alumina tape to be used in fixed partial dentures by way of topology optimization. Material and method: A maxillary anterior three-unit bridge alumina core with teeth form and surrounding periodontal apparatus model was used to ultimately design the most structurally rigid form of the connector. Loadings from a $0^{\circ}$, $45^{\circ}$ and $60^{\circ}$ to the axis of each tooth were applied and analyzed with the 3-D finite element analysis method. Using the results from these experiments, the topology optimization was applied and the optimal reinforcement layout of connector was obtained and the detail shape in the fixed partial denture core was designed. Results: The modified prosthesis with the form of a bulk in the lower lingual surface of the connector in the event, reduced the stress concentration up to 20% in the 3-D FEA. Conclusion: The formation of a bulk in the lower lingual connector area of an alumina core for a fixed partial denture decreases the stress to a clinically favorable measure but does not harm the esthetic point of view. This result illustrates the possibility of clinical application of the modified form designed by the topology optimization method.

• 대한치과보철학회지
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• 제38권3호
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• pp.375-381
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• 2000

The conventional approach for replacing missing maxillary lateral incisors dictates the placement of either a conventional porcelain-fused-to-metal (PFM)bridge, resin-bonded fixed partial denture, or single implant prosthesis. However, several appearance-related disadvantages have been reported in the use of a prosthesis which incorporates a metal substructure. To address these limitations, metal -free restorative alternatives have been recently developed to expand the clinical options when fabrication of these prostheses is indicated. This clinical report describes the treatment of patients with a missing maxillary lateral incisor where the dentition was non-invasively restored with resin-bonded fixed partial denture(RBFPD) using In-Ceram and Targis-Vectris system.

• 대한치과의사협회지
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• 제49권6호
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• pp.334-339
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• 2011

The purpose of this study was to investigate the oral health condition and dental treatment need of low socioeconomic elderly people. A total of 116 elderly people who visited Boramae Hospital were evaluated with oral examination and panoramic radiogaph. The results showed that the most expecting treatment of low income aged people was removable partial denture. It was very clear in the age group of 70-84. In the age group under 70, most of the patients wanted prosthodontic tratement using fixed partial denture or crown. As the result of this study, elderly people with low socioeconomic status under age 85 needed removable partial denture or fixed prosthesis than complete denture. It is necessary to develop a more expanding and customized Senile prosthetic restoration program.

• 대한치과보철학회지
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• 제55권3호
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• pp.325-330
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• 2017

단일 치아 상실 시 전부피개관을 유지장치로 사용하는 고정성 보철이나 임플란트를 이용한 치료가 우선적으로 선택되어 사용되고 있다. 하지만 전부 피개관 지대치 형성을 위해서는 건전한 치질을 많이 삭제해야 한다는 단점이 있다. 임플란트의 경우 인접 치아의 손상을 피할 수 있으나 환자의 구강 상태와 전신 상태에 따라 불가능하거나 일정기간 연기해야 하는 경우도 있다. 본 증례에서는 최소한의 치질 삭제로 젊은 환자와 치은 퇴축이 있는 환자의 단일 치아 상실을 수복하기 위해 레진 접착 고정성 보철물을 선택하였다. 모든 환자들이 심미적, 기능적으로 만족하였기에 이를 보고하는 바이다.

• 대한치과보철학회지
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• 제60권1호
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• pp.29-36
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• 2022

상악 무치악 환자의 구강 회복을 계획할 때 치료 방법으로 임플란트를 이용한 고정성 보철 수복과 총의치 수복 또는 임플란트를 이용한 오버덴쳐 등을 고려할 수 있다. 총의치 수복의 경우 추가적인 수술이 필요 없고 상대적으로 경제적이며 임플란트 지지 고정성 보철 수복의 경우 일반적으로 총의치 수복에 비해 기능적인 부분이 우수하지만 임상적으로 임플란트 식립이 어려운 경우가 존재한다. 최근에는 환자의 요구 및 잔존 치조골의 상태 등을 고려하여 부분적으로 임플란트를 식립한 후 임플란트 지지 서베이드 크라운을 이용한 가철성 국소의치 수복도 시도되고 있다. 본 증례는 상악 전방부의 임플란트 지지 서베이드 크라운을 이용한 가철성 국소의치 수복을 시행한 증례로 심미 및 기능적으로 만족할 만한 결과를 보여 보고하는 바이다.

• 대한치과기공학회지
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• 제35권4호
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• pp.303-312
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• 2013

Purpose: In this research, non-linear three dimensional finite element models with contact elements were constructed. For the investigations of the distributions of contact stresses, 3 units fixed partial dentures model were studied, especially on the interface of the gold screw and cylinder, abutment screw. Methods: 3 types of models were constructed ; the basic fixed partial denture in molar region with 3 units and 3 implants, the intermediate pontic fixed partial denture model with 3 units and 2 implants, and the extension pontic fixed partial denture model with 3 units and 2 implants. For all types, the external loading due to chewing was simulated by applying $45^{\circ}$ linguo-buccal loading of 300 N to the medial crown. For the simulation of the clamping force which clinically occurs due to the torque, thermal expansion was provided to the cylinder as a preload. Results: Under 300 N concentrated loading to the medial crown, the maximum contact stress between abutment screw and gold screw was 86.85~175.86MPa without preload, while the maximum contact stress on the same area was 25.59~57.84MPa with preload. Conclusion: The preloading affected the outcomes of the finite element stress analysis. Reflecting the clinical conditions, the preloading conditions should be considered for other practical study utilizing FEA. For the study of the contact stresses and related motions, various conditions, such as frictional coefficient changes, gap between contact surfaces, were also varied and analyzed.

• 대한치과보철학회지
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• 제59권1호
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• pp.88-96
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• 2021

다수 치아가 상실된 부분 무치악 환자에서 고정성 임플란트 보철, 가철성 국소의치를 이용한 치료와 더불어 최근에는 임플란트를 보조적으로 이용한 임플란트 융합 국소의치 또한 많이 이용되고 있다. 이중 부착 장치와 서베이드 고정성 보철물을 함께 이용하는 임플란트 융합 국소의치의 경우, 부착 장치와 국소의치가 동일한 삽입로를 가지도록 하는 것이 중요하다. 본 증례의 환자는 하악 국소의치를 사용하던 중, 불편감을 주소로 내원하여 임플란트 서베이드 고정성 보철물을 활용한 임플란트 융합 국소의치를 제작하였다. 이후 추가적인 임플란트 식립 시, 기존의 임플란트 서베이드 고정성 보철물의 삽입로와 동일한 식립 방향을 설정하기 위하여 디지털 가이드 수술을 이용하였다. 임플란트 식립 후, 좌, 우측 소구치부에는 로케이터를 장착하고, 좌측 구치부에는 치유 지대주 상태로 국소의치의 지지를 부여하여 제작하였다. 이를 통해 심미적, 기능적으로 만족할 만한 결과를 얻었기에 보고하는 바이다.