• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.34 no.5
• /
• pp.555-561
• /
• 2008

Purpose: The goal of this study was to develop a technique for creating a computerized composite maxillofacial-dental model, based on point-based surface best fit algorithm and to test its accuracy. The computerized composite maxillofacial-dental model was made by the three dimensional combination of a 3-dimensional (3D) computed tomography (CT) bone model with digital dental model. Materials and Methods: This integration procedure mainly consists of following steps : 1) a reconstruction of a virtual skull and digital dental model from CT and laser scanned dental model ; 2) an incorporation of dental model into virtual maxillofacial-dental model by point-based surface best fit algorithm; 3) an assessment of the accuracy of incorporation. To test this system, CTs and dental models from 3 volunteers with cranio-maxillofacial deformities were obtained. And the registration accuracy was determined by the root mean squared distance between the corresponding reference points in a set of 2 images. Results and Conclusions: Fusion error for the maxillofacial 3D CT model with the digital dental model ranged between 0.1 and 0.3 mm with mean of 0.2 mm. The range of errors were similar to those reported elsewhere with the fiducial markers. So this study confirmed the feasibility and accuracy of combining digital dental model and 3D CT maxillofacial model. And this technique seemed to be easier for us that its clinical applicability can good in the field of digital cranio-maxillofacial surgery.

• Journal of Technologic Dentistry
• /
• v.39 no.4
• /
• pp.227-233
• /
• 2017

Purpose: The purpose of this study was to evaluate the validity of digital models fabricated by difference optical source of non-contact 3D dental scanner. Methods: A master model with the prepared upper full arch tooth was used. Stone model(N=10) were produced from master model, and on the other hands, digital models were made with the 3D dental scanner(Blue, white, red optical source). The linear distance between the reference points were measured and analyzed on the Delcam $Copycad^{(R)}$ graphic software. The results were statistically analyzed using the one-way ANOVA and Tukey's HSD test(${\alpha}=0.05$). Results: There were considerable differences in mean values between optical source within each color(blue, white, red), and this difference was not statistically significant(p>0.05). Conclusion : Three different color of dental scanner optical source showed clinically acceptable accuracies of full arch digital model produced by them. Besides, these results will have to be confirmed in further clinical studies.

• Journal of Technologic Dentistry
• /
• v.34 no.2
• /
• pp.121-128
• /
• 2012

Purpose: The aim of this study was to determine the reliability and accuracy of measurements in digital models(CEREC$^{(R)}$ AC) compared to stone models. Methods: A master model(500B-1, Nissin Dental Product, Japan) with the prepared upper full arch tooth was used. Conventional impression and then stone model(n=10) were produced from this master model, and on the other hands, digital impressions were made with the CEREC$^{(R)}$ AC intra-oral scanner(n=10). One examiner measured two times the intercanine, intermolar distance, dental arch length. The stone model were measured using a digital caliper. The t-student test for paired samples and intraclass correlation coefficient(ICC) were used for statistical analysis. Results: The measurement of two methods showed very good reliability. At the intra-examiner reliability of measurement, ICC at the stone and CEREC$^{(R)}$ AC model were 0.81 and 0.94. The mean difference between measurements made directly on the stone models and those made on the CEREC$^{(R)}$ AC model was 0.20~0.28mm, and was statistically significant(P=0.001). Conclusion: These in vitro studies show that accuracy of the digital impression is similar to that of the conventional impression. These results will have to be confirmed in further clinical studies.

• The Journal of the Korean dental association
• /
• v.39 no.10 s.389
• /
• pp.849-853
• /
• 2001

• The Journal of the Korea Contents Association
• /
• v.12 no.10
• /
• pp.357-364
• /
• 2012

Dental scanner-based dental digital models have been developed that have the potential to replace conventional stone model. The aim of this study was examine the accuracy and reliability of measurements made on digital models. A master model with the prepared upper full arch tooth was used. Stone model(N=10) were produced from master model, and on the other hands, digital models were made with the white light scanner(Identica, korea). One examiner individually measured 6 parameters on the conventional model and the digital models on two occasions. The student's t-test for paired samples and intra-class correlation coefficient(ICC) were used for statistical analysis. At the intra-examiner reliability of measurement, ICC at the stone and digital models were 0.75 and 0.87. The mean difference between measurements made directly on the stone models and those made on the digital models was 0.11-0.23mm, and was statistically significant(P<0.05). These in vitro studies show that accuracy of the digital model is similar to that of the stone model. These results will have to be confirmed in further clinical studies.

• Journal of Korean Dental Science
• /
• v.15 no.2
• /
• pp.132-140
• /
• 2022

Purpose: Dental diagnostic records derived from study models are a popular method of obtaining reliable and vital information. Conventional plaster models are the most common method, however, they are being gradually replaced by digital impressions as technology advances. Moreover, three-dimensional dental models are becoming increasingly common in dental offices, and various methods are available for obtaining them. This study aimed to evaluate the accuracy of the measurement of dental digital models by comparing them with conventional plaster and to determine their clinical validity. Materials and Methods: The study was conducted on 16 patients' maxillary and mandibular dental models. Tooth size (TS), intercanine width (ICW), intermolar width (IMW), and Bolton analysis were taken by using a digital caliper on a plaster model obtained from each patient, while intraoral scans were manually measured using two digital analysis software. A one-way analysis of variance test was used to compare the dental measurements of the three methods. Result: No significant differences were reported between the TS, the ICW and IMW, and the Bolton analysis through the conventional and two digital groups. Conclusion: Measurements of TS, arch width, and Bolton analysis produced from digital models have shown acceptable clinical validity. No significant differences were observed between the three dental measurement techniques.

• Journal of Technologic Dentistry
• /
• v.35 no.1
• /
• pp.29-35
• /
• 2013

Purpose: The purpose of this study was to evaluate the validity of digital models fabricated by dental scannable stone. Methods: Twenty same cases of stone models(maxillary full arch) were manufactured. Intercanine distance, intermolar distance, two dental arch lengths(right, left), two diagonal of dental arch lengths(right, left) were measured for comparison. Each of ten stone models were measured by digital vernier calipers and scanned by dental scanner. Ten digital models were measured by CAD program. The mean(SDs) values were compared by a Mann-Whitney U test(${\alpha}$=0.05). Results: No statistically significant differences between the two groups were found at intermolar distance, dental arch length(right)(p>0.05). However, intercanine distance, dental arch length(left) and two diagonal of dental arch lengths(right, left) were statistically significant(p<0.05). Conclusion: Stone models fabricated by dental scannable stone showed larger than digital models.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.35 no.2
• /
• pp.55-63
• /
• 2019

The aim of this article was to review various methods used to evaluate the accuracy of digital dental models. When evaluating the accuracy of digital models, the errors can be reduced by educating examiners and using artificial landmarks. The accuracy evaluation methods of digital dental models are divided into linear measurement, 2-dimensional cross-sectional analysis, and 3-dimensional best fit measurement. As the technology of scanners develops, many studies have been conducted to compare the accuracy of digital impression and conventional impression. According to improvement of scan technologies and development of 3-dimensional model analysis software, the ability to evaluate the accuracy of digital models is becoming more efficient. In this article, we describe the methods for evaluating the accuracy of a digital model and investigate effective accuracy analysis methods for each situation.

• Journal of dental hygiene science
• /
• v.15 no.5
• /
• pp.673-678
• /
• 2015

The purpose of this study was to evaluate the reliability and accuracy of linear measurements in digital models compared to master model. A master model (ANKA-4; Frasaco GmbH, Tettnang, Germany) with the prepared upper full arch tooth was used. Four linear measurements were recorded between landmarks, directly on the master model and the digital models by a single examiner. Measurements were made with a digital caliper from manual model and with the software from the virtual models. The t-test for paired samples and intraclass correlation coefficient (ICC) were used for statistical analysis. The measurement of two methods showed good reliability. The mean differences between master and digital model were 0.06~0.12 mm. These in vitro studies show that accuracy and reliability of the digital impression is similar to that of the gold standard. Therefore digital impression was also considered to be a acceptable for placement clinically.

• Journal of dental hygiene science
• /
• v.15 no.2
• /
• pp.226-231
• /
• 2015

The purpose of this study was to evaluate the accuracy of model according to three types of dental scanner. A maxillary acrylic model was prepared and duplicated 10 times by silicone impression materials. Corresponding working casts were formed from scannable stone and got a 3-dimensional digital models using three different scanners. The distance of each measurement region was measured using vernier calipers and the respective program. One-way ANOVA and the Tukey honestly significant difference post hoc test (${\alpha}=0.05$) was performed using IBM SPSS Statistics 21.0. Overall, the stone cast is smaller than the digital models in measurement distance. And measuring point value of laser scanner showed the most similar values and measurement points value of digital vernier calipers. Digital model of white light scanner showed similar values in the measurement points value of the blue light scanner. In conclusion, the laser scanner showed the best accuracy among the three types of dental scanner. However, the difference between the digital models and the stone cast can be accommodated in making prostheses. Thereby, three types of dental scanner are available in a clinically acceptable range.