• Journal of Technologic Dentistry
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• v.39 no.1
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• pp.1-7
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• 2017

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)(${\alpha}=0.05$). Results: $RMS{\pm}SD$ with regard to repeatability were $14.7{\pm}2.5{\mu}m$, $17.1{\pm}4.0{\mu}m$, 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.

• Journal of Korean society of Dental Hygiene
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• v.11 no.3
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• pp.325-341
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• 2011

Objectives : This research has investigated the reality of the education of the claim and the degree of the education for the claimed of the dentistry recuperation organization in the Daejeon and Chuncheong are for the improvement of the problem in the medical expenses. Methods : It use as a basic data for the vitalizations of the education and performed the survey in the dentistry recuperation organization in the Daejeon and ChungCheong Nam BukDo which are registered in the evaluating organization for judging the health insurance in the present May 2010, and concluded just like the below. Results : 1. The education of the claim in the requirer in the dentistry recuperation organization, and the education of the claim was especially lacking when the dentist was studying in the university, and the dental hygienist had the similar educational experience in the school and the clinic (p<0.05) 2. Most of the requirer in the dental recuperation organization was hoping to get the education related to the claim work, but the dentist and the nurse's aid was relatively low (p<0.05) 3. For fixing the error of the claim, the participation and the extension of the judging standard of the insurance was the highest among the university subordinate dental hospital/dental hospital, but the health center was relatively low (p<0.05). 4. The dentist feels the economic burden in employing the special employee because the raising of the special judging people, compared to others, but the staffs such as the dental hygienist preferred it as one of ways to fix the error of the claim of the dental insurance (p<0.05) 5. Both dentists and the dental hygienist said proper time to teach the insurance was all needed in the school, and the clinic, but other workers relatively believed it should be held in the clinic (p<0.05). 6. The important factors to decide the participation of the lecture was in order of the contents of the lecture, the place of the lecture, the amount for the lecture, the superintendent of the lecture, whether it has gone through the educational score, and whether it has passed the conserving educational score was relatively less important in the university subordinate dentist/dentist, but the medical center was very effective as 4.50 (p<0.05) 7. Health Insurance Review and assessment service was very high as the managing department for supplying the lecture and the information, 70.5%, and the next was the Korean Dental Association/ Korean dental hygiene association, but dentists were preferring the association to manage in than the Health Insurance Review and assessment service to manage (p<0.05) 8. In preferring lecture for the inquiring the insurance, periodontal surgery was the highest as 4.51, the diagnosis standard for injection was high in the university subordinate hospital/dentists, and the more the year of the insurance inquiry, the less the doctor who was hoping for the lecture about the basic treatment. Conclusions : Taken together, it is decided that the inquiry education about the medical expense in the dentist, so the consistent and systematic education should be held to the related people, and from this, it is thought to reduce the problem of the inquiry of the medical expenses by fostering the knowledge and supplying the information which are related to the inquiry of the dentists.

• The Journal of Advanced Prosthodontics
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• v.13 no.2
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• pp.107-116
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• 2021

PURPOSE. Several studies focused on the accuracy of intra-oral scanners in implant dentistry, but the data of inter-implant distances were not widely mentioned. Therefore, this study aimed to evaluate the effect of distance between two implants on the surface distortion of scanned models generated by intra-oral scanners. MATERIALS AND METHODS. Three models with the distances between two fixed scan bodies of 7, 14, and 21 mm were fabricated and scanned with a highly precise D900L dental laboratory scanner as reference models. Fifteen scans were performed with TRIOS3 and CEREC Omnicam intra-oral scanners. Trueness, precision, and angle deviation of the test models were analyzed (α=.05). RESULTS. There was a significant difference among inter-implant distances in both intraoral scanners (P<.001). The error of trueness and precision increased with the increasing inter-implant length, while the angle deviation did not show the same trend. A significant difference in the angle deviation was found among the inter-implant distance. The greatest angle deviation was reported in the 14-mm group of both scanners (P<.05). In contrast, the lowest angle deviation in the 21-mm group of the TR scanner and the 7-mm of the CR scanner was reported (P<.001). CONCLUSION. The inter-implant distance affected the accuracy of intra-oral scanner. The error of trueness and precision increased along with the increasing distance between two implants. However, the distortions were not clinically significant. Regarding angle deviation, the clinically significant angle deviation may be possible when using intra-oral scanners in the partially edentulous arch.

• Imaging Science in Dentistry
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• v.53 no.3
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• pp.221-227
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• 2023

Purpose: This study was performed to develop a linear regression model using the pulp-to-tooth volume ratio (PTVR) ratio of the maxillary canine, assessed through cone-beam computed tomography (CBCT) images, to predict chronological age (CA) in Indonesian adults. Materials and Methods: A sample of 99 maxillary canines was collected from patients between 20 and 49.99 years old. These samples were obtained from CBCT scans taken at the Universitas Padjadjaran Dental Hospital in Indonesia between 2018 and 2022. Pulp volume (PV) and tooth volume (TV) were measured using ITK-SNAP, while PTVR was calculated from the PV/TV ratio. Using RStudio, a linear regression was performed to predict CA using PTVR. Additionally, correlation and observer agreement were assessed. Results: The PTVR method demonstrated excellent reproducibility, and a significant correlation was found between the PTVR of the maxillary canine and CA(r= -0.74, P<0.01). The linear regression analysis showed an R² of 0.58, a root mean square error of 5.85, and a mean absolute error of 4.31. Conclusion: Linear regression using the PTVR can be effectively applied to predict CA in Indonesian adults between 20 and 49.99 years of age. As models of this type can be population-specific, recalibration for each population is encouraged. Additionally, future research should explore the use of other teeth, such as molars.

• Journal of Technologic Dentistry
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• v.46 no.2
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• pp.28-35
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• 2024

Purpose: To evaluate the three-dimensional trueness of upper and lower denture bases produced using a digital light processing (DLP) printer and immersed in a constant-temperature water bath. Methods: An edentulous model was prepared and fitted with denture bases and occlusal rims manufactured using base plate wax. After scanning the model, denture bases, and occlusal rims, complete denture designs were created. Using the designs and a DLP printer, 10 upper and 10 lower complete dentures were manufactured. Each denture was scanned before (impression surface of upper denture base before constant temperature water bath [UBC] and impression surface of lower denture base before constant temperature water bath [LBC] groups) and after (impression surface of upper denture base after constant temperature water bath [UAC] and impression surface of lower denture base after constant temperature water bath [LAC] groups) immersion in the constant-temperature water bath. Scanned files were analyzed by comparing reference and scanned data, with statistical analysis conducted using the Kruskal-Wallis test (α=0.05). Results: Statistical analysis revealed no significant differences between the UBC and LBC groups, nor between the UAC and LAC groups (p>0.05). However, significant differences were observed between the UBC and UAC groups and between the LBC and LAC groups, i.e., before and after the constant-temperature water bath for both maxillary and mandibular denture bases (p<0.05). Conclusion: Denture bases not immersed in the constant-temperature water bath (UBC and LBC groups) exhibited error values within 100 ㎛, whereas those immersed in the water bath (UAC and LAC groups) showed error values exceeding 100 ㎛.

• The korean journal of orthodontics
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• v.29 no.4 s.75
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• pp.491-501
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• 1999

Precise and accurate measuring of tooth size is essential procedure in orthodontic diagnosis. The purpose of this study was to evaluate the reproducibility and accuracy of tooth size measurements with regard to tooth and investigator. Five investigators measured the size of one side of teeth, from central incisor to first molar, on 20 sets of casts that show a moderate degree of crowding. Mesio-distal width was measured with digital vernier calipers in each tooth and this procedure was repeated three times at two weeks interval. To obtain a standard measurement for each tooth, dental casts were cut into individual tooth, and its width was measured with micrometer. The difference between the measurement from dental cast and the standard measurement was defined as the measurement error. Through various statistical analyses, following results were obtained. 1. The reproducibility did not show significant differences with regard to tooth or investigator. 2. The measurement error showed some difference with regard to tooth and investigator. 3. The magnitude of the measurement error showed increasing tendency from anterior to posterior teeth with maximum value in the first molar. 4. While the measurements obtained on study casts generally showed smaller number compared to standard measurements, the direction of the difference showed variability according to tooth or investigator. 5. The measurement errors did not show significant correlations with the degree of crowding. The results of the present study indicate that the possibility of tooth size measurement error should be taken into consideration when diagnosing an orthodontic case.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.36 no.4
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• pp.262-269
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• 2010

Introduction: Accurate diagnosis and treatment planning are very important for orthognathic surgery. A small error in diagnosis can cause postoperative functional and esthetic problems. Pre-existing 2-dimensional (D) chephalogram analysis has a high likelihood of error due to its intrinsic and extrinsic problems. A cephalogram can also be inaccurate due to the limited anatomic points, superimposition of the image, and the considerable time and effort required. Recently, an improvement in technology and popularization of computed tomography (CT) provides patients with 3-D computer based cephalometric analysis, which complements traditional analysis in many ways. However, the results are affected by the experience and the subject of the investigator. Materials and Methods: The effects of the sources human error in 2-D cephalogram analysis and 3-D computerized tomography cephalometric analysis were compared using Simplant CMF program. From 2008 Jan to 2009 June, patients who had undergone CT, cephalo AP, lat were investigated. Results: 1. In the 3 D and 2 D images, 10 out of 93 variables (10.4%) and 11 out 44 variables (25%), respectively, showed a significant difference. 2. Landmarks that showed a significant difference in the 2 D image were the points frequently superimposed anatomically. 3. Go Po Orb landmarks, which showed a significant difference in the 3 D images, were found to be the artificial points for analysis in the 2 D image, and in the current definition, these points cannot be used for reproducibility in the 3 D image. Conclusion: Generally, 3-D CT images provide more precise identification of the traditional cephalometric landmark. Greater variability of certain landmarks in the mediolateral direction is probably related to the inadequate definition of the landmarks in the third dimension.

• Journal of dental hygiene science
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• v.14 no.4
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• pp.433-441
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• 2014

This study was aimed to analyze factors affecting intention on clinical application by task autonomy of dental hygienists, expected effect and obstructive factor on clinical application of assessment, dental hygiene diagnosis, planning, implementation, and evaluation (ADPIE). Meanwhile, it proved mediating effects of "attitude toward ADPIE" when it came to "intention on clinical application". The data was collected from 237 dental personnel in capital region from March 28, 2014 to May 2, 2014. To analyze the suitability of a theoretical model and hypothesis testing, SPSS 21.0 and AMOS 18.0 program were used. The theoretical model was accepted as it resulted in ${\chi}^2=421.67$ while showing goodness of fit index=0.858, comparative fit index=0.915, Tucker-Lewis index=0.896, root mean square residual=0.039, and root mean square error of approximation=0.099. The result showed "task autonomy of dental hygienists (${\beta}=0.398$, p<0.05)" and "expected effect on ADPIE (${\beta}=0.363$, p<0.01)" had a positive effect on "attitude toward ADPIE". Also, "attitude toward ADPIE" had a positive effect on "intention on clinical application". In addition, "task autonomy of dental hygienists" and "expected effect on ADPIE" had an indirect influence on "intention on clinical application" via such intermediary as "attitude toward ADPIE". According to the above results, the task autonomy of dental hygienists, expected effect on ADPIE, and attitude toward ADPIE were confirmed to be significant factors when it came to the intention on its clinical application. Therefore in order to settle ADPIE in the clinical practice, improvement of task autonomy for dental hygienists as well as their expectation and attitude on ADPIE must be promoted.

• Journal of the Korea Convergence Society
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• v.12 no.10
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• pp.137-144
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• 2021

The purpose of this study is to analyze the factors affecting the education experience, education needs, and knowledge level of calculation criteria for dental workers. It was conducted on dental workers in Daegu and Gyeongbuk province and an online survey was conducted using Google Survey. We used frequency analysis, crossover analysis, and ANOVA analysis method to find out general characteristic, education experience, education needs, and knowledge level according to education experience and education needs of candidates. As a result of in the knowledge level survey of dental health insurance, there were high rates of incorrect answers to the calculation criteria when the claim program automatically processes it or notifies you through an error window. The level of knowledge of candidates who are experienced, on a claim, and with experience in dental insurance training in the last six months was high. In conclusion, it seems that accurate and correct insurance claims are possible when the dental workers are familiar with the calculation criteria changed through regular dental health insurance education. We look forward to this study providing basic data in preparation of education system for professional dental insurance claims for dental workers.

• The Journal of Advanced Prosthodontics
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• v.15 no.6
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• pp.281-289
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• 2023

PURPOSE. This study aimed to predict the positional coordinates of incisor points from the scan data of conventional complete dentures and verify their accuracy. MATERIALS AND METHODS. The standard triangulated language (STL) data of the scanned 100 pairs of complete upper and lower dentures were imported into the computer-aided design software from which the position coordinates of the points corresponding to each landmark of the jaw were obtained. The x, y, and z coordinates of the incisor point (X_P, Y_P, and Z_P) were obtained from the maxillary and mandibular landmark coordinates using regression or calculation formulas, and the accuracy was verified to determine the deviation between the measured and predicted coordinate values. Y_P was obtained in two ways using the hamularincisive-papilla plane (HIP) and facial measurements. Multiple regression analysis was used to predict Z_P. The root mean squared error (RMSE) values were used to verify the accuracy of the X_P and Y_P. The RMSE value was obtained after crossvalidation using the remaining 30 cases of denture STL data to verify the accuracy of Z_P. RESULTS. The RMSE was 2.22 for predicting X_P. When predicting Y_P, the RMSE of the method using the HIP plane and facial measurements was 3.18 and 0.73, respectively. Cross-validation revealed the RMSE to be 1.53. CONCLUSION. Y_P and Z_P could be predicted from anatomical landmarks of the maxillary and mandibular edentulous jaw, suggesting that Y_P could be predicted with better accuracy with the addition of the position of the lower border of the upper lip.