유리섬유 보강재 첨가에 따른 레진 의치상의 강화효과

김총명,김웅철,김지환,김혜영 대한치과기공학회 2014 대한치과기공학회지 Vol.36 No.1

드릴 반경 설정이 보철물 가공에 미치는 영향

김총명,김소리,조미향 대한치과기공학회 2018 대한치과기공학회지 Vol.40 No.1

Purpose: The purpose of this study is to evaluate the trueness and fitness of machined prostheses according to drill radius setting in CAD software. Methods: For this study, standard abutment were replicated in Type Ⅳ stone. The stone abutment were scanned using a dental scanner. The CAD design software was designed using scanned abutment data. When designing, the drill radius was set to 0.3 mm and 0 mm, respectively, and saved. The saved design data was milled using a milling machine (n=13). The inner surface of the milled crown was scanned. The trueness and fitness were measured using the inner scan data of prostheses. Independent t-tests were performed to identify significant differences in each data. Results: Trueness values of the data saved with 0.3 mm and 0 mm drill radius were 18.9 ±2.3 ㎛ and 19.1 ±0.9 ㎛, respectively. There was no statistically significant difference between the groups. Fitness values of the data saved with 0.3 mm and 0 mm drill radius were 65.5 ±0.8 ㎛ and 33.8 ±1.0 ㎛, respectively. There was a statistically significant difference between the groups (p<.05). Conclusion : Setting the drill radius is important to produce clinically good fit prostheses.

2종류의 버와 3종류의 버를 이용해 제작된 크라운 보철물의 정밀도 평가

김총명,전진훈,이재준,김지환,김웅철 대한치과기공학회 2016 대한치과기공학회지 Vol.39 No.2

Purpose: The purpose of this study was to assess precision of crown prostheses that were fabricated by using 2 kinds of bur or 3 kinds of bur. Methods: The crowns were fabricated by using the first molar of the right maxillary in this study. The abutments that were prepared were scanned by using a scanner and designed by using CAD software. Based on the crown design, NC data were created with CAM software. The created NC data were used while fabricating the crown prostheses by using 5-axis milling machine. Scanning was done for the internal and external surface of the completed crown prostheses and 3-dimensional measurement was conducted for precision assessment. Results: The RMS±SD value for the external surface of the crown prostheses that was fabricated by using two burs and three burs were 28.5±4.1㎛ and 19.1±2.8㎛, respectively; and the value for two burs were bigger than that for three burs with statistical significance (p<0.001). The RMS±SD value for the internal surface of the crown prostheses that was fabricated by using two burs and three burs were 14.9±1.9㎛ and 13.3±2.5㎛, respectively;and the value for two burs were bigger than that for three burs but with no statistical significance. Conclusion: Based on this study, the prostheses that were fabricated by using 3 bur presented better stability compared to those that were fabricated by using 2 bur and statistically significant difference was found only in the external surface.

5축 밀링으로 가공한 PMMA 3본 브릿지의 내면 적합도 평가

김총명,김재홍,김지환,김웅철 대한치과기공학회 2016 대한치과기공학회지 Vol.39 No.2

Purpose: The purpose of this study was to assess the internal fitness of the PMMA 3-unit bridge that was fabricated with 5-axis milling machine and to verify the clinically allowable values. Methods: For fabrication of the crown bridge in this study, 25-27 abutment teeth were used. The prepare abutment teeth were scanned with a scanner and 3-unit bridge was designed by using design software. Upon the completion of the design, the 3-unit bridge was fabricated by using a PMMA block with 5-axis milling machine. The internal surface of the fabricated 3-unit bridge was scanned by using a scanner and the difference between the 3-unit bridge and the abutment teeth was assessed by merging them together. Results: RMS±SD values for PRE group, MOL group, and BRI group were 51.2±18.2, 44.8±10.0, and 52.1±8.3㎛, respectively. The mean of the PRE group was bigger than that of the MOL and BRI group; however, statistically significant difference was not found (p>0.05). Conclusion: The PMMA 3-unit bridge that was fabricated with 5-axis milling machine presented stable internal values for each crown and overall internal values were within the range of clinically allowable values.

5축 밀링으로 가공한 PMMA 3본 브릿지의 내면 적합도 평가

김총명,김웅철,김재홍,김지환 대한치과기공학회 2016 대한치과기공학회지 Vol.38 No.2

Purpose: The purpose of this study was to assess the internal fitness of the PMMA 3-unit bridge that was fabricated with 5-axis milling machine and to verify the clinically allowable values. Methods: For fabrication of the crown bridge in this study, 25-27 abutment teeth were used. The prepare abutment teeth were scanned with a scanner and 3-unit bridge was designed by using design software. Upon the completion of the design, the 3-unit bridge was fabricated by using a PMMA block with 5-axis milling machine. The internal surface of the fabricated 3-unit bridge was scanned by using a scanner and the difference between the 3-unit bridge and the abutment teeth was assessed by merging them together. Results: RMS±SD values for PRE group, MOL group, and BRI group were 51.2±18.2, 44.8±10.0, and 52.1±8.3㎛, respectively. The mean of the PRE group was bigger than that of the MOL and BRI group; however, statistically significant difference was not found (p>0.05). Conclusion: The PMMA 3-unit bridge that was fabricated with 5-axis milling machine presented stable internal values for each crown and overall internal values were within the range of clinically allowable values.

2종류의 버와 3종류의 버를 이용해 제작된 크라운 보철물의 정밀도 평가

김총명,전진훈,김웅철,이재준,김지환 대한치과기공학회 2016 대한치과기공학회지 Vol.38 No.2

Purpose: The purpose of this study was to assess precision of crown prostheses that were fabricated by using 2 kinds of bur or 3 kinds of bur. Methods: The crowns were fabricated by using the first molar of the right maxillary in this study. The abutments that were prepared were scanned by using a scanner and designed by using CAD software. Based on the crown design, NC data were created with CAM software. The created NC data were used while fabricating the crown prostheses by using 5-axis milling machine. Scanning was done for the internal and external surface of the completed crown prostheses and 3-dimensional measurement was conducted for precision assessment. Results: The RMS±SD value for the external surface of the crown prostheses that was fabricated by using two burs and three burs were 28.5±4.1㎛ and 19.1±2.8㎛, respectively; and the value for two burs were bigger than that for three burs with statistical significance (p<0.001). The RMS±SD value for the internal surface of the crown prostheses that was fabricated by using two burs and three burs were 14.9±1.9㎛ and 13.3±2.5㎛, respectively;and the value for two burs were bigger than that for three burs but with no statistical significance. Conclusion: Based on this study, the prostheses that were fabricated by using 3 bur presented better stability compared to those that were fabricated by using 2 bur and statistically significant difference was found only in the external surface.

퍼스널 모빌리티 기반 실내 위치 추정 및 주행 시스템 구축

이총명(Chong-Myeong Lee),마완준(Wan-Jun Ma),한수정(Soo-Jeong Han),김하람(Ha-Ram Kim),최재붕(Jae-Boong Choi),이태린(Tae-Rin Lee) 대한기계학회 2019 대한기계학회 춘추학술대회 Vol.2019 No.11

In this paper, a personal mobility system for autonomous driving within buildings is suggested by using magnetic field and LiDAR sensors. The sensor network is utilized to measure the driving direction and the distance from obstacles and walls. In addition, to improve the accuracy of indoor positing system, a lane detection algorithm based services are demonstrated on the floor From the indoor environment, test users can autonomously drive the personal mobility without help. Finally, we will introduce how the indoor mobility system will change our daily life in the concept of smart city.

Characteristics of pediatric genital injuries: a 10-year, single-emergency center, retrospective study

최수복,김총명 대한응급의학회 2023 대한응급의학회지 Vol.34 No.4

Objective: This 10-year, single-center, retrospective study was conducted to examine the characteristics of pediatric genital injuries in a Korean emergency department (ED) setting. Methods: The current study was conducted on 96 children (n=96) with genital injuries who presented to the ED of our medical institution during a 10-year period between July 16, 2013, and June 15, 2022. The diverse factors associated with the patients’ outcomes were examined. Logistic regression analysis was performed, for which the odds ratio (OR) and 95% confidence interval (CI) were calculated to identify factors contributing to complications. Results: Outdoors were more prevalent places of genital injuries than indoors in both boys and girls (64.3% and 48.5%, respectively). Straddle injury was the most common injury in boys and girls (35.7% and 64.7%, respectively). The penis and labia were the most prevalent injured organs in boys and girls-53.6% (15/28) and 60.3% (41/68), respectively. Of the patients, 7.3% (7/96) presented with wound infection. Multivariate logistic regression analysis showed that a delay to surgery >8 hours (OR, 0.74; 95% CI, 0.10-0.86; P=0.026) and the presence of wound contamination (OR, 3.76; 95% CI, 1.01-13.94; P=0.048) contributed to the occurrence of complications. Conclusion: The results showed that the age of 4-5 years, female sex, and straddle injury were closely associated with a relatively higher prevalence of pediatric genital injuries. In addition, a delay to surgery >8 hours and wound contamination contributed to complications. Nevertheless, further large-scale studies will be needed to establish the results.

Evaluation of marginal and internal gaps of Ni-Cr and Co-Cr alloy copings manufactured by microstereolithography

김동연,김총명,김지환,김혜영,김웅철 대한치과보철학회 2017 The Journal of Advanced Prosthodontics Vol.9 No.3

PURPOSE. The purpose of this study was to evaluate the marginal and internal gaps of Ni-Cr and Co-Cr copings, fabricated using the dental μ-SLA system. MATERIALS AND METHODS. Ten study dies were made using a twostep silicone impression with a dental stone (type IV) from the master die of a tooth. Ni-Cr (NC group) and Co-Cr (CC group) alloy copings were designed using a dental scanner, CAD software, resin coping, and casting process. In addition, 10 Ni-Cr alloy copings were manufactured using the lost-wax technique (LW group). The marginal and internal gaps in the 3 groups were measured using a digital microscope (160 ×) with the silicone replica technique, and the obtained data were analyzed using the non-parametric Kruskal-Wallis H test. Post-hoc comparisons were performed using Bonferroni-corrected Mann-Whitney U tests (α=.05). RESULTS. The mean (± standard deviation) values of the marginal, chamfer, axial wall, and occlusal gaps in the 3 groups were as follows: 81.5±73.8, 98.1±76.1, 87.1±44.8, and 146.8±78.7 μm in the LW group; 76.8±48.0, 141.7±57.1, 80.7±47.5, and 194.69±63.8 μm in the NC group; and 124.2±52.0, 199.5±71.0, 67.1±37.6, and 244.5±58.9 μm in the CC group. CONCLUSION. The marginal gap in the LW and NC groups were clinically acceptable. Further improvement is needed for CC group to be used clinical practice.

치과 캐드캠 ISO평가 기준에 준한 지대치 경석고 모형 및 인상체 스캐닝의 반복측정안정성 비교 평가

전진훈,황성식,김총명,김동연,김지환,김웅철 대한치과기공학회 2017 대한치과기공학회지 Vol.39 No.1

Purpose: The purpose of this in vitro study compared to evaluation of repeatability of scanning abutment tooth stone model and impression applied CAD/CAM ISO standard in dentistry. Methods: To evaluate repeatability of scanning abutment tooth stone model, were repeatedly scanned to obtain 11 data via 3D stereolithography (STL) files. 10 data (STL files) were compared with the first 3D data (STL file), and the error sizes were measured by using 3D superimposing software(n=10). Also, the repeatability of scanning abutment tooth impression was evaluated with the same procedure. Independent t test was performed to evaluate the repeatability of scanning abutment tooth stone model versus impression through root mean square(RMS) and standard deviation(SD)(α=0.05). Results: RMS±SD with regard to repeatability were 14.7±2.5㎛, 17.1±4.0㎛, respectively, with scanning abutment tooth stone model and impression(p=0.129). Conclusion: This study results showed a little different repeatability of scanning abutment tooth stone model and impression applied CAD/CAM ISO standard in dentistry, will suggest futures good studies and clinical advantages.