• The Journal of Advanced Prosthodontics
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• 제12권3호
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• pp.173-180
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• 2020

PURPOSE. This study compared digital (reference point matching) and replica methods for measuring marginal and internal fit of full coverage restorations. MATERIALS AND METHODS. A maxillary left first molar typodent was fixed on to an aluminum base and prepared to receive all-ceramic full coverage restoration. The model was scanned with an intraoral scanner (CEREC Omnicam, Sirona, York, PA, USA). Twelve crowns were fabricated from lithium disilicate blocks (IPS emax CAD, Ivoclar Vivadent) and then crystalized. Marginal and internal fit of each restoration was measured by two examiners using replica and a new digital three-dimensional technique. Reliability between the two methods and two examiners was assessed by correlation and Cronbach's Alpha coefficient (P<.05). A Bland-Altman assessment for agreement was used to compare the two methods. RESULTS. Bland-Altman assessment showed that the mean of difference for marginal, absolute marginal, and axial gap was respectively -1.04 ㎛, -41.9 ㎛, and -29.53 ㎛ with limit of agreement (LOA) between -37.26 to 35.18 ㎛ for marginal, -105.85 to 22.05 ㎛ for absolute marginal and -80.52 to 22.02 ㎛ for axial gap. Positive correlation for repeatability (P<.05) in determining marginal and internal gaps by the two examiners in both techniques was revealed. Reliability of both techniques in all sites of measurements was at least good (0.8 ≤ α < 0.9). CONCLUSION. Both measuring techniques appeared highly reliable for evaluating fit of fixed dental restorations, while reference point matching provided higher values in axial and absolute marginal gap assessment.

• 대한소아치과학회지
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• 제26권2호
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• pp.240-247
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• 1999

치아우식증, 외상, 발육성 결함으로 광범위한 수복이 필요한 유전치의 치료는 소아치과의사에게 있어 매우 까다로운 문제이다. 이상적인 수복술식은 강도, 내구성, 심미성과 장착의 효율성을 모두 갖추어야 한다. 이에 행동조절문제가 있는 어린이를 치료하는 기술적 문제를 더하면, 여러 가능한 수복 방법 중에서 적절한 술식을 선택하는 것은 어려운 일이다. 현재 사용되는 수복술식에는 복합레진의 접착을 사용한 celluloid strip crown, conventional stainless steel crown, open-faced stainless steel crown, commercially 및 chairside veneered stainless steel crown과 epoxy-coated stainless steel crown 등이 있다. 이 모든 술식이 나름대로의 기술적, 기능적 또는 심미적 단점을 갖고 있어 각각의 효율적이고 효과적인 사용을 위해서는 적절한 선택이 중요하다. 이에 저자는 이러한 여러 가지의 전장피개수복 방법을 사용해 유전치를 치료하여 그 결과를 보고하는 바이다.

• Restorative Dentistry and Endodontics
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• 제43권4호
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• pp.38.1-38.9
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• 2018

The restoration of endodontically treated teeth (ETT) with more than one cusp missing and thin remaining walls is challenging for the general practitioner. The use of posts combined with full coverage restorations is a well-established approach, yet not following the minimal invasive principles of adhesive dentistry. Endocrowns are indirect monoblock restorations that use the pulp chamber of the ETT for retention. In this study the fabrication of 4 endocrowns and their clinical performance will be discussed. Two clinical cases include computer-aided design/computer-aided manufacturing manufactured molar endocrowns (one feldspathic ceramic and one hybrid composite-ceramic restoration) and the other two are dental laboratory manufactured resin composite premolar endocrown restorations. The modified United States Public Health Service criteria were used to assess the clinical behavior of the restorations at different follow up periods. Endocrown restorations present a satisfactory clinical alternative, either by the use of resin composite or glass ceramic and hybrid materials. Specific guidelines with minimal alterations should be followed for an endocrown restoration to be successful. Due to limited evidence regarding the long term evaluation of this restorative technique, a careful selection of cases should be applied.

• 대한소아치과학회지
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• 제26권1호
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• pp.103-108
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• 1999

광범위한 치질파괴가 있는 상악유전치를 갖는 소아에서 silicoater technique에 의한 veneered stainless steel crown으로 수복 후 $3{\sim}12$개월 동안 주기적 검사와 수복물의 평가 결과, 다음과 같은 결론을 얻었다. 1. 행동조절이 어려운 소아에서 chair time을 감소시킴으로써 행동조절에 도움을 주었다. 2. 유지력, 내구성, 심미성이 우수하였으므로 유전치부의 광범위한 치질손상시 유용한 수복방법이다.

• 한국환경복원기술학회지
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• 제15권1호
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• pp.133-140
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• 2012

The study of Arundinaria munsuensis Y. Lee to this day was limited to the field of morphological species classification since its first discovery at Jiri mountain in the late 1990s. This native plants, one of Korean endemic species found in Jiri Mt. necessitates further studies about its use as revegetation plants or groundcover plants in urban areas. This study was launched from this need followed by summaries of results below related to its usage. This targeted species is a native Korean species which its natural distribution on the subalpine zone has merit for the wide range of climatic adaptation. Also, the coverage rate reached 78.3% in three years mostly by rhizome growth with an expectation of full coverage in four years providing less maintenance needs after planting. The net price for the construction of pot seedling methods of this plants is relatively economical than other normal revegetation construction methods. For these reasons, drilling for the plants on cut and fill soil slopes driven from pot seedling adapts Arundinaria munsuensis Y. Lee as efficient revegetation plant. Total construction cost for pot seedling work($30cm{\times}30cm$) of Arundinaria munsuensis was approximately 21,000won which is in reasonable price range when compared to other revegetation construction methods of disturbed slopes. As a native Korean plant, Arundinaria munsuensis has wide range of climatic adaptation with less maintenance requirement after planting. This study may suggest a strong possibility of Arundinaria munsuensis as a pot planting material in sloped area.

• Restorative Dentistry and Endodontics
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• 제43권1호
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• pp.9.1-9.6
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• 2018

The objective of this case report is to introduce a simple technique for simultaneously taking a closed-mouth impression and functionally generated path (FGP) for a full coverage crown restoration. A monolithic zirconia crown was the restoration of choice. An alginate impression of the abutment tooth was taken to fabricate a custom-made closed-mouth impression tray covering the abutment tooth and the adjacent teeth. The tray had an FGP table and an abutment tray in cameo and intaglio surfaces, respectively. The impression was taken with silicone impression material after adjusting the abutment tray and inscribing the FGP using self-curing acrylic resins. Plaster casts were made from the impression, and a zirconia crown was fabricated. The crown was cemented to the abutment tooth with minimal adjustments. This simple technique resulted in a well-fitting crown that accounted for mandibular movements. Using the custom closed-mouth impression tray incorporating an FGP table simultaneously aids in fabricating an accurately fitting restoration that incorporates harmonious mandibular movements using a single impression capture.

• The Journal of Advanced Prosthodontics
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• 제12권6호
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• pp.344-350
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• 2020

PURPOSE. Recently introduced hybrid and reinforced glass ceramic computer-aided design/computer-aided manufacturing (CAD/CAM) materials have been used for full-coverage restorations. However; the effect of adjustment and type of materials on internal and marginal adaptation are unknown. This study aimed to evaluate and compare the marginal and internal adaptations of crowns made of three different CAD/CAM materials before and after adjustment. MATERIALS AND METHODS. One acrylic resin maxillary first molar was prepared and served as the master die. Thirty-six restorations were fabricated using CAD/CAM system (CEREC Omnicam, MCXL) with three materials including lithium disilicate (IPS e.max CAD), zirconia-reinforced lithium silicate (Suprinity), and hybrid ceramic (Enamic). Internal and marginal adaptations were evaluated with the reference point matching technique before and after adjustment. The data were analyzed using mixed ANOVA considering α=.05 as the significance level. RESULTS. The effect of adjustment and its interaction with the restoration material were significant for marginal, absolute marginal, and occlusal discrepancies (P<.05). Before adjustment, Suprinity had lower marginal discrepancies than IPS e.max CAD (P=.18) and Enamic (P=.021); though no significant differences existed after adjustment. CONCLUSION. Within the limitations of this study, crowns fabricated from IPS e.max CAD and Suprinity resulted in slightly better adaptation compared with Enamic crowns before adjustment. However, marginal, axial, and occlusal discrepancies were similar among all materials after the adjustment.

• 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.

• Journal of Yeungnam Medical Science
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• 제40권3호
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• pp.302-307
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• 2023

With recent developments in digital dentistry, research on techniques and materials for three-dimensional (3D) printing is actively underway. We report the clinical applications and outcomes of 3D printing of temporary crowns fabricated with polylactic acid (PLA) using a fused deposition modeling (FDM) printer. Five participants were recruited from among patients scheduled to be treated with a single full-coverage crown at a dental clinic in a university medical center from June to August 2022. We used 3D-printed crowns fabricated with PLA using an FDM printer as temporary crowns and were assessed for discomfort, fracture, and dislodging. The 3D-printed temporary crowns were maintained without fracture, dislodging, or discomfort until the permanent prosthesis was ready. The average time required for printing the temporary crowns was approximately 7 minutes. The 3D printing of temporary crowns with PLA using an FDM printer is a convenient process for dentists. However, these crowns have some limitations, such as rough surface texture and translucency; therefore, the 3D printing process should be improved to produce better prostheses.

• 대한소아치과학회지
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• 제39권3호
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• pp.242-248
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• 2012

유아기에서의 적절한 우식 치료는 장기간의 향상된 구강 건강 상태를 유지할 수 있는 토대가 된다. 치아 우식증, 외상 또는 발육성 결함 존재시 유전치의 수복치료가 필요하며 기능과 심미, 발음 면에서 올바른 기능을 수행하도록 이루어져야 한다. 여러 가능한 수복 방법 및 재료 선택에 있어 적절한 술식을 선택하는 것은 어려운 일이며, 치과의사마다 치료 결정 여부 및 술식 선택에 있어 다양한 기준을 갖고 있다. 본 연구 조사는 유전치 우식 치료와 관련하여 소아치과 의사와 일반치과 의사를 대상으로 치료 결정 여부 및 수복 방법, 그리고 재료 선택을 알아보고자 설문 조사를 시행한 결과 다음과 같은 결론을 얻었다. 1. 초기 우식 치료에 있어서 소아치과 의사는 예방 치료의 빈도가 높은데에 비해, 일반치과 의사는 수복치료의 빈도가 높게 나타났다. 2. 수복재의 선택 기준으로는 양군 모두에서 조작성을 가장 높게 꼽았다. 3. 전치부 심미 수복의 경우 소아치과 의사는 전부 피개법을, 일반 치과의사는 일부 수복법을 선택하는 경향이 높았다. 4. 상아질 우식을 보이는 치아를 치료하지 않는 잔여수명에 관하여, 소아치과의사는 평균 2.0년, 일반 치과의사는 1.2년을 기준으로 하고 있는 것으로 나타났다. 5. 생리적 치근 흡수를 보이는 치아에 대한 수복치료에 있어서, 소아치과 의사는 치근 흡수가 없거나 치근 길이가 $67.6{\pm}10.9%$ 이상 남은 경우, 일반 치과의사는 치근 길이가 $62.2{\pm}10.0%$ 이상 남은 경우에 치료를 하는 것으로 나타났다. 6. 상아질 우식증을 가진 만 1세 유아에 대하여, 소아치과 의사의 84%, 일반치과 의사의 52%가 예방치료를 먼저 시행하였으며, 일반치과 의사의 41%는 소아치과로 의뢰하는 것으로 나타났다.