• The Journal of Advanced Prosthodontics
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• 제15권5호
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• pp.227-237
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• 2023

PURPOSE. This study aimed to assess and compare the color stability, flexural strength (FS), and surface roughness of occlusal splints fabricated from heat-cured acrylic resin, milled polymethyl methacrylate (PMMA)-based resin, and 3D-printed (PMMA) based-resin. MATERIALS AND METHODS. Samples of each type of resin were obtained, and baseline measurements of color and surface roughness were recorded. The specimens were divided into three groups (n = 10) and subjected to distinct aging protocols: thermomechanical cycling (TMC), simulated brushing (SB), and control (without aging). Final assessments of color and surface roughness and three-point bending test (ODM100; Odeme) were conducted, and data were statistically analyzed (2-way ANOVA, Tukey, P <.05). RESULTS. Across all resin types, the most significant increase in surface roughness (Ra) was observed after TMC (P < .05), with the 3D-printed resin exhibiting the lowest Ra (P < .05). After brushing, milled resin displayed the highest Ra (P < .05) and greater color alteration (∆E₀₀) compared to 3D-printed resin. The most substantial ∆E₀₀ was recorded after brushing for all resins, except for heat-cured resin subjected to TMC. Regardless of aging, milled resin exhibited the highest FS (P < .05), except when compared to 3D-printed resin subjected to TMC. Heat-cured resin exposed to TMC demonstrated the lowest FS, different (P < .05) from the control. Under control conditions, milled resin exhibited the highest FS, different (P < .05) from the brushed group. 3D-printed resin subjected to TMC displayed the highest FS (P < .05). CONCLUSION. Among the tested resins, 3D-printed resin demonstrated superior longevity, characterized by minimal surface roughness and color alterations. Aging had a negligible impact on its mechanical properties.

• 대한치과보철학회지
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• 제48권3호
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• pp.194-201
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• 2010

연구 목적: 본 연구는 지르코니아 코핑의 다양한 디자인과 시멘트 종류에 따른 지르코니아 도재관의 파절 저항성과 변연 적합도를 평가하고자 하였다. 연구 재료 및 방법: CAD/CAM system (Everest, KAVO Dental GmbH, Biberach, Germany)을 이용하여, 다양한 두께를 가진 지르코니아 코핑을 디자인하고 제작하였다. 80개의 코핑을 디자인에 따라 20개씩 4개의 그룹으로 분류하였으며, 각 그룹은 다시 시멘트 종류에 따라 시편을 10개씩 나누어 2개의 소그룹으로 분류하였다. Group I은 전체적으로 균일하게 0.3 mm로, group II는 협면과 협측 교합면은 0.3 mm, 설면과 설측 교합면을 0.6 mm, group III은전체0.6 mm 균일하게, Group IV는 협면과 협측 교합면은 0.6 mm 설면과 설측 교합면을 1.0 mm로 디자인 하였다. Putty index를 이용해 같은 크기와 형태의 지르코니아 도재관을 축성 후, 완성하였다. 미세 경도측정기의 현미경 (Matsuzawa, MXT-70, Japan)으로 도재관의 변연 적합도를 측정하였고, 만능시험기 (Z020, Zwick, Germany)를 이용하여 cross-head speed를 1 mm/min로 도재관이 파절될 때까지 수직 하중을 가해 파절 저항성을 측정하였다. One-way ANOVA와 two-way ANOVA 를 이용해 그 결과를 비교 분석 하였으며, 사후 검정으로 Duncan's multiple range test ($\alpha$=0.05)를 사용하였다. 결과:1. 코핑 디자인에 따른 변연적합성은 유의한 차이가 있었다 (P<.05). 2. 임시합착제 (Cavitec$^{(R)}$)로 합착한 군에서 코핑 디자인에 따른 지르코니아 도재관의 파절강도는 유의한 차이가 있었다 (P<.05). 3. 영구접착제 (Panavia-$F^{(R)}$)로 접착한 군에서 코핑 디자인에 따른 지르코니아 도재관의 파절강도는 통계학적인 유의차가 없었다 (P>.05). 4. 시멘트의 종류에 따른 동일한 디자인사이에서의 파절강도는 group I과 group II에서 Panavia-F 접착군이 Cavitec$^{(R)}$ 접착군보다 통계학적으로 유의성 있게 높았다 (P<.05). 5. 도재관의 파절 양상은 지르코니아 코핑의 디자인에 따른 차이는 없었으며, 시멘트의 종류에 따라 Cavitec$^{(R)}$ 접착군에서는 시편이 완전 분리되는 전부 파절, Panavia-$F^{(R)}$ 접착군에서는 전장 도재층에서만 파절되는 부분파절이 주로 나타났다. 결론: 제한된 결과이기는 하나 심미성을 위해 가시면을 얇게 하고 강도를 위해 비가시면의 지르코니아 코핑을 두껍게 하는, 즉 기능에 따라 두께를 달리 하는 세라믹 하부구조 디자인이 임상에서 선택적으로 활용될 수 있을 것으로 사료되었다.

• 대한치과의사협회지
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• 제54권12호
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• pp.996-1023
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• 2016

There are many kinds of maintenance care services for removable denture patient. Adjustment of the denture base and occlusion should be performed regularly not only for pain relief but also for maintaining the denture function. Direct and indirect relining are needed frequently in specific cases including mandibular distal extension case or non-symmetric residual teeth situation. Surface treatments for metal and resin are essential in the relining procedure. Clinical process for the denture repair is similar to indirect relining which needs inter-occlusal registration. Especially, the peridontal maintenance care and caries prevention are most important way to preserve the abutment teeth in partial edentulism. Moreover, the caring method for the denture and the tissue should be instructed to the denture patient.

• 대한치과보존학회:학술대회논문집
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• 대한치과보존학회 2003년도 제120회 추계학술대회 제 5차 한ㆍ일 치과보존학회 공동학술대회
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• pp.609-609
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• 2003

I. Objectives The purpose of this study was to evaluate the effect of adhesive property on microtensile bond strength and to determine the failure mode. II. Materials and Methods Flat occlusal dentin surfaces were prepared using low-speed diamond saw. The dentin was etched with 37% phosphoric acid. The following adhesives were applied to the etched dentin according to manufacturer's directions；Scotchbond Multi-Purpose in group 1, Primer＆Bond NT in group 2, Scotchbond Multi-Purpose followed by Tetric-flow in group 3. After adhesive application, a cylinder of resin-based composite was built up the occlusal surface.(omitted)

• 대한치과보철학회지
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• 제56권3호
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• pp.243-249
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• 2018

과도한 치아 마모를 가진 환자들을 치료를 시작할 때 수직교합고경의 상실과 수복을 위한 공간의 적절성으로 분류하게 된다. 본 증례의 환자는 80세의 여성으로 구치부 교합지지가 상실되어 대합치가 정출하면서 교합평면의 붕괴가 일어나고 잔존 치아의 마모 증가가 동반되어 보철을 위한 약간의 악간 공간의 상실이 발생하였다. 이러한 경우 최소한의 수직교합고경의 증가를 부여하고 안정화기간을 거쳐 안정된 교합접촉을 제공한다면 성공적으로 치료할 수 있다. 본 증례에서는 수직고경의 증가를 동반하여 단일 구조 지르코니아를 이용한 고정성 보철물과 상악 가철성 국소의치로 수복을 하였고 이러한 치료과정을 통하여 기능적, 심미적으로 만족스러운 결과를 얻어 보고하는 바이다.

• 대한치과보철학회지
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• 제61권4호
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• pp.284-292
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• 2023

안정적인 구치부 교합지지는 적절한 저작기능과 정상적인 안모의 유지를 위해 매우 중요하다. 특히 65세 이상의 고령환자에서는 저작기능이 충분한 영양섭취와 환자의 전신건강에 직접적인 영향을 미친다. 본 증례에서는 상악 무치악, 하악 양측 구치부 치아 상실을 보이는 고령환자의 구치부 교합지지를 회복해주기 위해 상악 총의치를 제작하여 이상적인 교합평면을 설정하였고, 하악 양측 구치부에 컴퓨터 가이드 임플란트 식립 수술을 진행하였다. 임플란트 지지 임시 수복물을 이용한 임플란트 즉시부하를 통해 환자가 수술 후에도 음식 섭취를 원활하게 할 수 있도록 하였다. 하악 구치부 지르코니아 고정성 보철수복을 완료한 후, 상악 총의치 인공치의 교합면을 Cobalt-Chrome계 금속 합금으로 치환하여 마모 저항성을 향상시켰다. 상악 가철성 총의치, 하악 양측 구치부 고정성 보철 치료를 통해 환자의 교합지지와 저작기능을 빠르게 회복해주고, 최종 치료단계에서는 마모에 대한 장기적 안정성도 얻을 수 있었기에 이를 보고하고자 한다.

• 대한치과의사협회지
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• 제12권9호
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• pp.707-712
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• 1974

The 800 extracted permanent teeth of first and second premolar were observed and obtained the following results: Those teeth were extracted from the population of dentistless rural area. The cause of extraction of those teeth was only the dental caries. It was performed by the free dental service team from 1966 to 1973. The findings were as follows: 1. The most incidence of caries occurrence was on the distal surface and the least was mesial side occlusal surface. 2. The average rate of decayed surface was higher in the second premolar group than the first permolar. 3. The average rate of decayed surface was higher in the teeth of mandible than maxilla. 4. The average rate of decayed surface was higher in female than male. 5. The average rate of decayed surface per tooth was 3.05±1.83.

• 대한치과보철학회지
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• 제33권3호
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• pp.413-439
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• 1995

The purpose of this study was to evaluate the stress distribution developed in the supporting structures by mandibular distal extension removable partial dentures with 2 different direct retainer designs and with or without indirect retainer and abutment splinting. The examined direct retainers on the second bicuspid abutment tooth were Akers clasp and RPA clasp, the indirect retainer was located on the mesial fossa of the first bicuspid, and the first and second bicuspid were splinted in case of tooth splinting. Total 8 cases were compared and analyzed with 3-dimensional finite element method. 150N were applied vertically on the artificial teeth of the removable partial denture, and then stress distribution patterns were analyzed and compared. The results were as follows : 1. The forces transmitted to the abutment tooth were primarily from the occlusal rests. 2. The abutment tooth was displaced distally when the force was applied. The compressive stress was observed at the distal root surface of the abutment tooth and the tensile stress, at the mesial root surface. 3. The denture base was displaced posteriorly and inferiorly when the force was applied. At the more distal portion of the denture base, the greater displacement was observed.And the anterior portion of the major connector was displaced superiorly. 4. The occlusal rest placed on the distal part of the abutment tooth tended to tip the tooth more posteriorly than did one on the mesial part of that tooth. 5. Severe superior displacement was observed at the anterior portion of the major connector in case of removable partial dentures without indirect retainer. 6. In case of tooth-splinting, the stress was distributed through all the root surface of both abuments. In case of no tooth-splinting, the stress was concentrated on the distal root surface of the primary abutment.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제43권2호
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• pp.70-76
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• 2017

The purpose of this study was to perform a literature review of short implants in the posterior maxilla and to assess the influence of different factors on implant success rate. A comprehensive search was conducted to retrieve articles published from 2004 to 2015 using short dental implants with lengths less than 10 mm in the posterior maxilla with at least one year of follow-up. Twenty-four of 253 papers were selected, reviewed, and produced the following results. (1) The initial survival rate of short implants in the posterior maxilla was not related to implant width, surface, or design; however, the cumulative success rate of rough-surface short implants was higher than that of machined-surface implants especially in performance of edentulous dental implants of length <7 mm. (2) While bone augmentation can be used for rehabilitation of the atrophic posterior maxilla, short dental implants may be an alternative approach with fewer biological complications. (3) The increased crown-to-implant (C/I) ratio and occlusal table (OT) values in short dental implants with favorable occlusal loading do not seem to cause peri-implant bone loss. Higher C/I ratio does not produce any negative influence on implant success. (4) Some approaches that decrease the stress in posterior short implants use an implant designed to increase bone-implant contact surface area, providing the patient with a mutually protected or canine guidance occlusion and splinting implants together with no cantilever load. The survival rate of short implants in the posterior edentulous maxilla is high, and applying short implants under strict clinical protocols seems to be a safe and predictable technique.

• 대한치과기공학회지
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• 제46권2호
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• pp.28-35
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• 2024

Purpose: To evaluate the three-dimensional trueness of upper and lower denture bases produced using a digital light processing (DLP) printer and immersed in a constant-temperature water bath. Methods: An edentulous model was prepared and fitted with denture bases and occlusal rims manufactured using base plate wax. After scanning the model, denture bases, and occlusal rims, complete denture designs were created. Using the designs and a DLP printer, 10 upper and 10 lower complete dentures were manufactured. Each denture was scanned before (impression surface of upper denture base before constant temperature water bath [UBC] and impression surface of lower denture base before constant temperature water bath [LBC] groups) and after (impression surface of upper denture base after constant temperature water bath [UAC] and impression surface of lower denture base after constant temperature water bath [LAC] groups) immersion in the constant-temperature water bath. Scanned files were analyzed by comparing reference and scanned data, with statistical analysis conducted using the Kruskal-Wallis test (α=0.05). Results: Statistical analysis revealed no significant differences between the UBC and LBC groups, nor between the UAC and LAC groups (p>0.05). However, significant differences were observed between the UBC and UAC groups and between the LBC and LAC groups, i.e., before and after the constant-temperature water bath for both maxillary and mandibular denture bases (p<0.05). Conclusion: Denture bases not immersed in the constant-temperature water bath (UBC and LBC groups) exhibited error values within 100 ㎛, whereas those immersed in the water bath (UAC and LAC groups) showed error values exceeding 100 ㎛.