• 대한소아치과학회지
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• 제47권2호
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• pp.176-187
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• 2020

이 연구는 모델 스캐너로 석고 모형을 스캔한 디지털 모형(Model scanned digital model, MSD)과 구내 스캐너로 구강을 스캔한 디지털 모형(Intraoral scanned digital model, ISD)에서 계측한 치아 근원심 폭경(Tooth width, TW)과 치열궁 길이(Arch length, AL)의 신뢰도와 재현성, 치열궁 길이 편차(Arch length discrepancy, ALD) 분석의 타당도를 평가하였다. 만 12 - 18세의 남, 여 30명에게 석고 모형, MSD, ISD를 획득하고, 2번 계측한 TW, AL의 신뢰도는 Pearson 상관 분석, 4명의 재현성은 군간 상관 분석 그리고 TW, AL 및 ALD의 타당도는 대응표본 t검정으로 평가하였다. 결과적으로 모든 군에서 계측한 TW, AL는 높은 신뢰도와 재현성을 보였고 MSD군의 ALD분석은 적절한 타당도를 보였다. ISD 군의 TW는 가장 높은 타당도를 보인 반면에, AL와 ALD분석은 유의미하게 짧게 측정되어 낮은 타당도를 보였으므로 임상가는 디지털 모델을 이용하여 공간 분석 시행 시 이를 고려해야 할 것이다.

• The Journal of Advanced Prosthodontics
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• 제14권6호
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• pp.388-398
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• 2022

PURPOSE. This in vitro study aimed to evaluate the accuracy of 14 different intraoral scanners for the All-on-4 treatment concept. MATERIALS AND METHODS. Four implants were placed in regions 13, 16, 23, and 26 of an edentulous maxillary model that was poured with scannable Type 4 gypsum to imitate the All-on-4 concept. The cast was scanned 10 times for each of 14 intraoral scanners (Primescan, iTero 2, iTero 5D, Virtuo Vivo, Trios 3, Trios 4, CS3600, CS3700, Emerald, Emerald S, Medit i500, BenQ BIS-I, Heron IOS, and Aadva IOS 100P) after the polyether ether ketone scanbody was placed. For the control group, the gypsum model was scanned 10 times with an industrial scanner. The first of the 10 virtual models obtained from the industrial model was chosen as the reference model. For trueness, the data of the 14 dental scanners were superimposed with the reference model; for precision, the data of all 14 scanners were superimposed within the groups. Statistical analyses were performed using the Kolmogorov-Smirnov, Shapiro-Wilks, and Dunn's tests. RESULTS. Primescan showed the highest trueness and precision values (P < .005), followed by the iTero 5D scanner (P < .005). CONCLUSION. Some of these digital scanners can be used to make impressions within the All-on-4 concept. However, the possibility of data loss due to artifacts, reflections, and the inability to combine the data should be considered.

• 대한소아치과학회지
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• 제49권1호
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• pp.14-24
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• 2022

이 연구의 목적은 디지털 치열 모형에서 치아 폭경, 볼튼 비율, 수평 피개, 수직 피개를 포함한 교정적 측정의 타당성을 확인하는 것이다. 만 12 - 18세의 환자를 대상으로 세가지 형태의 치열 모형을 획득하였다. 기존의 석고 모형을 형성하였고, DOF freedom HD 모형 스캐너를 통해 디지털 모형으로 변환하였다. 그리고 CS3600 구강 스캐너로 디지털 모형을 형성하였다. 각 모형에서 측정 시행 후, 급내 상관 계수를 통해 계측의 신뢰성과 재현성을 확인하였으며, 대응 표본 t 검정을 사용하여 타당성을 평가하였다. 결과적으로 모든 군에서 급내 상관계수는 0.750을 초과하여 연구자 내 신뢰성과 연구자 간 재현성이 있음을 확인하였다. 모형 스캔한 군은 전체 및 전치 볼튼 비율, 수평 및 수직 피개에서 타당성을 보였다. 구강 스캔한 군은 전치 볼튼 비율, 수평 피개에서 타당성을 보였다. 구강 스캔한 디지털 모형을 이용한 계측은 인상 채득에 어려움이 있는 소아 청소년에게 고려할 수 있는 대안이다. 하지만 임상에서 이를 교정적 분석에 이용할 경우 오차를 고려한 적용이 필요하다.

• The Journal of Advanced Prosthodontics
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• 제15권4호
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• pp.179-188
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• 2023

PURPOSE. This in vitro study aimed to evaluate the performance of digital intraoral scanners in a completely edentulous patient with angled and parallel implants. MATERIALS AND METHODS. A total of 6 implants were placed at angulations of 0°, 5°, 0°, 0°, 15°, and 0° in regions #36, #34, #32, #42, #44, and #46, respectively, in a completely edentulous mandibular polyurethane model. Then, the study model created by connecting a scan body on the implants was scanned using a model scanner, and a 3D reference model was obtained. Three different intraoral scanners were used for digital impressions (PS group, TR group, and CS group, n = 10 in each group). The distances and angles between the scan bodies in these measurement groups were measured. RESULTS. While the Primescan (PS) impression group had the highest accuracy with 38 ㎛, the values of 104 ㎛ and 171 ㎛ were obtained with Trios 4 IOSs (TR) and Carestream 3600 (CS), respectively (P = .001). The CS scanner constituted the impression group with the highest deviation in terms of accuracy. In terms of dimensional differences in the angle parameter, a statistically significant difference was revealed among the mean deviation angle values according to the scanners (P < .001). While the lowest angular deviation was obtained with the PS impression group with 0.185°, the values of 0.499° and 1.250° were obtained with TR and CS, respectively. No statistically significant difference was detected among the impression groups in terms of precision values (P > .05). CONCLUSION. A statistically significant difference was found among the three digital impression groups upon comparing the impression accuracy. Implant angulation affected the impression accuracy of the digital impression groups. The most accurate impressions in terms of both distance and angle deviation were obtained with the PS impression group.

• The Journal of Advanced Prosthodontics
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• 제8권3호
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• pp.219-223
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• 2016

PURPOSE. This study aimed to create a digitized database of fabricated obturators to be kept for patients' potential emergency needs. MATERIALS AND METHODS. A chairside intraoral scanner was used to scan the surfaces of an acrylic resin obturator. The scanned data was recorded and saved as a single standard tessellation language file using a three-dimensional modeling software. A simulated obturator model was manufactured using fused deposition modeling technique in a three-dimensional printer. RESULTS. The entire obturator was successfully scanned regardless of its structural complexity, modeled as three-dimensional data, and stored in the digital system of our clinic at a relatively small size (19.6 MB). A simulated obturator model was then accurately manufactured from these data. CONCLUSION. This study provides a proof-of-concept for the use of digital technology to create a digitized database of obturators for edentulous maxillectomy patients.

• 대한치과교정학회지
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• 제48권4호
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• pp.262-267
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• 2018

The aim of this study was to test the clinical application of an intraoral scanner for serial evaluation of orthodontic tooth movement. The maxillary dentitions of eight patients with fixed orthodontic appliances were scanned using an intraoral scanner at the beginning of treatment (T0), and at 1 month (T1), 2 months (T2), 3 months (T3), and 4 months (T4) after T0. The serial digital models were superimposed on the palatal surface as a reference area, and the linear and angular changes of the central incisors, canines, and first molars were evaluated. The intraclass correlation coefficient and method errors showed that this method was clinically acceptable. Various types of orthodontic tooth movements, including minute movements, could be observed every month. The intraoral scanner and digital superimposition technique enabled the serial evaluation of orthodontic tooth movement without taking serial impressions and/or acquiring radiographs.

• The Journal of Advanced Prosthodontics
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• 제8권5호
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• pp.354-362
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• 2016

PURPOSE. The trueness and precision of acquired images of intraoral digital scanners could be influenced by restoration type, preparation outline form, scanning technology and the application of power. The aim of this study is to perform the comparative evaluation of the 3-dimensional reproducibility of intraoral scanners (IOSs). MATERIALS AND METHODS. The phantom containing five prepared teeth was scanned by the reference scanner (Dental Wings) and 5 test IOSs (E4D dentist, Fastscan, iTero, Trios and Zfx Intrascan). The acquired images of the scanner groups were compared with the image from the reference scanner (trueness) and within each scanner groups (precision). Statistical analysis was performed using independent two-samples t-test and analysis of variance (${\alpha}=.05$). RESULTS. The average deviations of trueness and precision of Fastscan, iTero and Trios were significantly lower than the other scanners. According to the restoration type, significantly higher trueness was observed in crown and inlay than in bridge. However, no significant difference was observed among four sites of preparation outline form. If compared by the characteristics of IOS, high trueness was observed in the group adopting the active triangulation and using powder. However, there was no significant difference between the still image acquisition and video acquisition groups. CONCLUSION. Except for two intraoral scanners, Fastscan, iTero and Trios displayed comparable levels of trueness and precision values in tested phantom model. Difference in trueness was observed depending on the restoration type, the preparation outline form and characteristics of IOS, which should be taken into consideration when the intraoral scanning data are utilized.

• The Journal of Advanced Prosthodontics
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• 제13권5호
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• pp.316-326
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• 2021

PURPOSE. Purpose of this in vitro study was to determine the accuracy of different intraoral scans versus laboratory scans of impressions and casts for the digitization of an edentulous maxilla. MATERIALS AND METHODS. A PEEK model of an edentulous maxilla, featuring four hemispheres on the alveolar ridges in region 13, 17, 23 and 27, was industrially digitized to obtain a reference dataset (REF). Intraoral scans using Cerec Primescan AC (PRI) and Cerec AC Omnicam (OMN), as well as conventional impressions (scannable polyvinyl siloxane) were carried out (n = 25). Conventional impressions (E5I) and referring plaster casts were scanned with the inEOS X5 (E5M). All datasets were exported in STL and analyzed (Geomagic Qualify). Linear and angular differences were evaluated by virtually constructed measurement points in the centers of the hemispheres (P13, P17, P23, P27) and lines between the points (P17-P13, P17-P23, P17-P27). Kolmogorov-Smirnov test and Shapiro-Wilk test were performed to test for normal distribution, Kruskal-Wallis-H test, and Mann-Whitney-U test to detect significant differences in trueness, followed by 2-sample Kolmogorov-Smirnov test to detect significant differences in precision (P < .008). RESULTS. Group PRI showed the highest trueness in linear and angular parameters (P < .001), while group E5I showed the highest precision (P < .001). CONCLUSION. Intraoral scan data obtained using Primescan showed the highest trueness while the indirect digitization of impressions showed the highest precision. To enhance the workflow, indirect digitization of the impression itself appears to be a reasonable technique, as it combines fast access to the digital workflow with the possibility of functional impression of mucosal areas.

• 구강회복응용과학지
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• 제34권2호
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• pp.104-115
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• 2018

목적: 본 연구는 현재 시판되고 있는 구강스캐너를 사용하여 구강스캐너 정확도 평가를 위해 국제표준이 제안하고 있는 모형의 스캔이미지 획득이 가능한 지 분석하고, 이를 통해 표준모델이 가지고 있는 문제점을 파악하는 데 있다. 연구 재료 및 방법: ISO12836과 ANSI/ADA no.132에서 규정하는 국제표준을 참고하여 3D 프린터기를 이용하여 모델을 제작하였으며, 모델스캐너와 두 가지 구강스캐너를 이용하여 스캔을 하였다. 스캔이미지 획득 정도를 3등급으로 분류하여 스캐너의 성능을 비교하였으며, 모델 표면의 상태에 따른 이미지 획득 능력도 비교하였다. 결과: 모델 스캐너가 모든 모델에서 가장 우수한 이미지를 얻을 수 있었으며 TRIOS3는 둥근 형태의 구조물, CS3500은 각진 형태의 구조물에 대한 이미지 재현이 좋은 결과를 보였다. 표준 모델의 표면상태에 따른 스캔이미지 재현에서는 초경석고 모델이 스캐너 종류와 관계없이 가장 우수하였다. 3D 프린팅 모델의 경우, 표면에 파우더 처리를 한 모델에서 가장 우수한 스캔이미지를 얻을 수 있었다. 결론: ISO12836과 ANSI/ADA 132의 표준모델의 경우, 구강스캐너의 field of view (FOV)를 벗어나는 구조물을 스캔할 때 서로 다른 면인 것을 구분하는 기준점이 존재하지 않게 되면 연속적인 스캔 및 정합과정에서 정확한 이미지를 나타내지 못한다는 것을 알 수 있었다. 그러므로 단순한 패턴의 반복과 대칭구조를 가지지 않는 새로운 표준모델이 필요하다고 여겨진다.

• Journal of Korean Dental Science
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• 제15권1호
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• pp.1-8
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• 2022

Purpose: Intraoral scanners, desktop scanners, and cone-beam computed tomography (CBCT) are being used in a complementary way for diagnosis and treatment planning. Limited patient-based results are available about dimensional reproducibility among different three-dimensional imaging systems. This study aimed to evaluate dimensional reproducibility among patient-derived digital models created from an intraoral scanner, desktop scanner, and two CBCT systems. Materials and Methods: Twenty-nine arches from sixteen patients who were candidates for implant treatments were enrolled. Different types of CBCT systems (KCT and VCT) were used before and after the surgery. Polyvinylsiloxane impressions were taken on the enrolled arches after the healing period. Gypsum casts were fabricated and scanned with an intraoral scanner (CIOS) and desktop scanner (MDS). Four test groups of digital models, each from CIOS, MDS, KCT, and VCT, respectively, were compared to the reference gypsum cast group. For comparison of linear measurements, intercanine and intermolar widths and left and right canine to molar lengths were measured on individual gypsum cast and digital models. All measurements were triplicated, and the averages were used for statistics. Bland-Altman plots were drawn to assess the degree of agreement between each test group with the reference gypsum cast group. A linear mixed model was used to analyze the fixed effect of the test groups compared to the reference group (α=0.05). Result: The Bland-Altman plots showed that the bias of each test group was -0.07 mm for CIOS, -0.07 mm for MDS, -0.21 mm for VCT, and -0.25 mm for KCT. The linear mixed model did not show significant differences between the test and reference groups (P>0.05). Conclusion: The linear distances measured on the digital models created from CIOS, MDS, and two CBCT systems showed slightly larger than the references but clinically acceptable reproducibility for diagnosis and treatment planning.