• The Journal of Advanced Prosthodontics
• /
• 제5권3호
• /
• pp.248-255
• /
• 2013

PURPOSE. This study compared the effect of three intraoral repair systems on the bond strength between composite resin and zirconia core. MATERIALS AND METHODS. Thirty zirconia specimens were divided into three groups according to the repair method: Group I-CoJet$^{TM}$ Repair System (3M ESPE) [chairside silica coating with $30{\mu}m$ $SiO_2$ + silanization + adhesive]; Group II-Ceramic Repair System (Ivoclar Vivadent) [etching with 37% phosphoric acid + Zirconia primer + adhesive]; Group III-Signum Zirconia Bond (Heraus) [Signum Zirconia Bond I + Signum Zirconia Bond II]. Composite resin was polymerized on each conditioned specimen. The shear bond strength was tested using a universal testing machine, and fracture sites were examined with FE-SEM. Surface morphology and wettability after surface treatments were examined additionally. The data of bond strengths were statistically analyzed with one-way ANOVA and Tamhane post hoc test (${\alpha}$=.05). RESULTS. Increased surface roughness and the highest wettability value were observed in the CoJet sand treated specimens. The specimens treated with 37% phosphoric acid and Signum Zirconia Bond I did not show any improvement of surface irregularity, and the lowest wettability value were found in 37% phosphoric acid treated specimens. There was no significant difference in the bond strengths between Group I ($7.80{\pm}0.76$ MPa) and III ($8.98{\pm}1.39$ MPa). Group II ($3.21{\pm}0.78$ MPa) showed a significant difference from other groups (P<.05). CONCLUSION. The use of Intraoral silica coating system and the application of Signum Zirconia Bond are effective for increasing the bond strength of composite resin to zirconia.

• 대한치과보철학회지
• /
• 제53권3호
• /
• pp.244-249
• /
• 2015

최근 디지털 기술이 발달하면서 임플란트 식립 시 가이드 템플릿을 이용하는 컴퓨터 가이드 수술이 활발하게 이루어지고 있으며, 임플란트 보철시 구강스캐너를 이용하는 방법이 소개되고 있다. 가이드 템플릿의 제작방법은 크게 RP 제작 시스템과 벡터 밀링 시스템으로 나눌 수 있는데, 각각은 우수한 정확성에도 불구하고 임상적 적용에 있어 약간의 아쉬운 점을 보이고 있다. 이에 본 증례에서는 CBCT 및 구강스캐너로 획득한 디지털 영상을 이용하여 쾌속조형법으로 왁스재료의 작업모형을 제작하고 그 위에 교정용 레진으로 금속애관을 픽업해 내는 방법을 사용하여 임플란트 수술용 가이드 템플릿을 제작하여 수술에 사용하였으며, 임상적으로 임플란트 식립 및 최종보철물 제작 시 만족스러운 결과를 얻을 수 있어서 이를 보고하고자 한다.

• 대한치과보철학회지
• /
• 제58권1호
• /
• pp.67-76
• /
• 2020

컴퓨터 지원 설계 제조 기술(CAD/CAM)의 발전에 따라, 완전한 디지털 워크플로우를 구현하기 위한 첫번째 단계인 구내스캐너의 중요성이 높아지기 시작했다. CAD/CAM 이중스캔 기술은 임시 수복물의 외형을 복제하여 최종 수복물에 반영하도록 하는 방법이다. 이 증례에서는 비심미적인 전치부, 중증도의 마모, 수직 고경의 감소를 보이는 67세 남성을 치관 연장술과 수직고경 회복을 동반한 완전구강회복을 통해 치료했다. 임시 수복물은 구내스캐너와 CAD/CAM 이중스캔을 이용해 제작되었다. 적응 기간 후, 최종 단일 구조 지르코니아 수복물을 CAD/CAM 이중스캔을 이용해 임시 수복물을 반영해 제작되었다.

• 대한치과의사협회지
• /
• 제58권4호
• /
• pp.194-205
• /
• 2020

Objective: The purpose of this study was to evaluate the accuracy of the inter-arch relationship of digital models generated using two types of intraoral scanners. Methods: In total, 34 plaster model samples were used. Two corresponding digital models were created using two types of intraoral scanners. A total of 15 variables were measured. The plaster model was directly measured using a digital caliper, while the digital models were measured using a software. The accuracy of the measurements was evaluated using repeated measures analysis of variance and the Friedman test. Results: Among the 15 measurements, 6 measurements[Overjet, Overbite, DZ_11-41 (Distance between the gingival zenith of maxillary right central incisor and mandibular right central incisor), DZ_16-46 (Distance between the gingival zenith of maxillary right first molar and mandibular right first molar), DZ_13-33 (Distance between the gingival zenith of maxillary right canine and mandibular left canine), and DZ_23-43 (Distance between the gingival zenith of maxillary left canine and mandibular right canine)]showed statistically significant differences, with DZ_23-43 showing the largest difference of 0.18 mm. The other measurements showed no statistically significant differences. Conclusions: Regardless of the type of scanner used for preparation, digital models can be used as clinically acceptable alternatives to conventional plaster models.

• 대한치과기공학회지
• /
• 제37권1호
• /
• pp.1-7
• /
• 2015

Purpose: The aim of this study was to evaluate the marginal and internal gap of wax copings fabricated from extraoral scanning with intraoral scanning. Methods: Fifteen study models(abutment of teeth 16) were made by PMMA. STL files of thirty abutment were prepared by intraoral scanning with extraoral scanning. Wax copings of thirty fabricated using CAD/CAM system. Marginal and internal gap of wax copings of thirty were measured by silicone replica technique and digital microscope(${\times}140$). Date were analyzed by using independent samples t-test. Results: Mean (SD) of two group were measured $55.61(27.42){\mu}m$ for totally gap of ES group and $60.67(33.14){\mu}m$ for totally gap of IS group. But marginal and internal gap of two group were not differences statistically significant(p>0.05). Conclusion: Evaluation of marginal and internal gap of two group showed that no differences statistically significant and clinically acceptable results.

• Imaging Science in Dentistry
• /
• 제31권1호
• /
• pp.51-55
• /
• 2001

Purpose : This study was performed to compare the diagnostic ability of conventional intraoral radiographs with that of digital subtraction image and to assess the quantifying ability of digital subtraction image for simulated apical root resorption Materials and Methods : Conventional intraoral radiographs and digital images of ten sound maxillary central incisors and those with simulated apical root resorption were taken with varying horizontal and vertical angulations of the x-ray beam. The diagnostic accuracy to detect the lesion was evaluated on conventional intraoral radiographs and digital subtraction images by ROC analysis. The amount of simulated apical root resorption was also estimated on the reconstruction images by Emago/sup (R)/ and compared with actual amount of tooth loss using paired t-test. Results: The diagnostic accuracy of conventional intraoral radiographs to detect the apical root resorption was low (ROC area = 0.6446), and the sensitivity and the specificity of digital subtraction images were 100%, respectively. The calculated amounts of apical root resorption showed no statistically significant difference with the actual amounts of the lesion (p>0.05). Conclusion: Digital subtraction radiography is powerful tool to detect the small apical root resorption, and quantitative analysis of small amounts of the lesion can be evaluated by digital subtraction radiography.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• 제30권4호
• /
• pp.353-358
• /
• 2008

Purpose: The purpose of this clinical retrospective study was to evaluate our experience of radial forearm free flap for reconstruction of the oral cavity. Material and methods: From 1997 to 2006, 50 radial forearm free flaps were employed for head and neck reconstruction in 50 patients at department of oral and maxillofacial surgery, Yonsei University, Korea. Data were obtained from chart review, and clinical follow-up. Results: Patients' age ranged from 26 to 82 years (mean 53.2). There were 39 men and 11 women. 43 of the 50(86%) patients had squamous cell carcinoma. The total flap survival were 47(94%), complication rate were revealed for 15(30%). Conclusion: In the reconstruction of soft tissue within the oral cavity, several free flaps have been used. Because of its constant anatomy, long pedicle allows a hypothetic vascular anastomosis in the contralateral neck, contourability for various type of oral defects, pliability and can be used simultaneous reconstruction in intraoral and extra oral defects, the radial forearm free flap constitutes one of the best choice of intraoral soft tissue reconstruction.

• Restorative Dentistry and Endodontics
• /
• 제40권1호
• /
• pp.58-67
• /
• 2015

Objectives: This study aimed to compare the accuracy of conventional intraoral (CI) radiography, photostimulable phosphor (PSP) radiography, cone beam computed tomography (CBCT) and multidetector computed tomography (MDCT) for detection of strip and root perforations in endodontically treated teeth. Materials and Methods: Mesial and distal roots of 72 recently extracted molar were endodontically prepared. Perforations were created in 0.2, 0.3, or 0.4 mm diameter around the furcation of 48 roots (strip perforation) and at the external surface of 48 roots (root perforation); 48 roots were not perforated (control group). After root obturation, intraoral radiography, CBCT and MDCT were taken. Discontinuity in the root structure was interpreted as perforation. Two observers examined the images. Data were analyzed using Stata software and Chi-square test. Results: The sensitivity and specificity of CI, PSP, CBCT and MDCT in detection of strip perforations were 81.25% and 93.75%, 85.42% and 91.67%, 97.92% and 85.42%, and 72.92% and 87.50%, respectively. For diagnosis of root perforation, the sensitivity and specificity were 87.50% and 93.75%, 89.58% and 91.67%, 97.92% and 85.42%, and 81.25% and 87.50%, respectively. For detection of strip perforation, the difference between CBCT and all other methods including CI, PSP and MDCT was significant (p < 0.05). For detection of root perforation, only the difference between CBCT and MDCT was significant, and for all the other methods no statistically significant difference was observed. Conclusions: If it is not possible to diagnose the root perforations by periapical radiographs, CBCT is the best radiographic technique while MDCT is not recommended.

• 턱관절균형의학회지
• /
• 제8권1호
• /
• pp.24-29
• /
• 2018

본 증례에서는 발병한지 1개월 된 환상미각증 환자에게 FCST의 CBA를 이용한 상부 경추 교정 치료를 시행하여 환상미각 증상이 완전 소실되는 변화를 관찰하였다. 다른 치료를 병행 하지 않고 CBA를 이용한 상부 경추 교정 치료만으로 효과를 본 것에 임상적 의의가 있다. 뇌신경계의 안정을 목표로 비침습적인 구강내 장치를 이용하여 미각이상 증상의 개선을 관찰하였고, 추후 미각장애에 대하여 FCST 치료의 가능성을 확인하였다.

• 대한치과보철학회지
• /
• 제59권1호
• /
• pp.126-133
• /
• 2021

여러 연구에서 임플란트 지지 보철물의 수직 침하에 대해 보고되고 있지만, 구강내 임플란트 지지보철물의 기능 시 수직침하 양상에 대해서는 알려진 바 없다. 본 증례에서는 2명의 환자에서 구치부 단일 치아 임플란트 지지 보철물의 3차원적인 변화를 평가하였다. 내부연결형 임플란트를 식립하였으며 통상적인 방법으로 Screw-Cement Retained Prosthesis(SCRP) 형태의 보철물을 제작해 장착하였다. 구강스캐너(Cerec Omnicam, Dentsply Sirona, USA)를 이용해 보철물 장착 시, 장착 1주, 1개월, 1년 후 구강 스캔을 시행하였으며 디지털 분석 프로그램(Geomagic Control X, 3D systems, USA)을 이용해 기간에 따른 위치 변화를 3차원적으로 평가하였다. 인접 치아를 기준으로 보철물 장착 후 임상적인 위치 변화가 나타났으며 변화량은 시간이 지남에 따라 증가하였다.