• The Journal of Korean Academy of Prosthodontics
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• v.61 no.1
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• pp.44-54
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• 2023

In order to manufacture functional and esthetic prostheses, it is essential to accurately transmit information about the patient's occlusal plane. In particular, in the case of a completely edentulous patient, the occlusal plane is very important to correctly support the soft tissue, to achieve aesthetic harmony with the facial appearance, and to properly pronounce it, and to form a balanced occlusal relationship for stable mastication. In the conventional method, various facebow systems were used to transmit patient's information from the clinic to the laboratory, but there were several limitations in the process of transferring them to CAD. To simplify this process, a prefabricated POP (PNUD Occlusal Plane) Bow system was recently developed. In this case, a CAD-CAM (Computer-aided design-computer-aided manufacturing) treatment dentures reflecting the patient's occlusal plane information was manufactured using the POP Bow system during the treatment of a completely edentulous patient, and aesthetic and functional satisfaction was obtained.

• Journal of Technologic Dentistry
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• v.44 no.2
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• pp.31-37
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• 2022

Purpose: The aim of this study was to evaluate the accuracy of provisional crowns manufactured using a milling machine and a digital light processing (DLP) printer. Methods: A full-contour crown was designed using computer-aided design software. Provisional crowns of this design were manufactured using a milling machine and using a DLP three-dimensional (3D) printer (N=20). The provisional crowns were digitized with an extraoral scanner, and 3D deviation analysis was applied to the scanned data to confirm their accuracy. An independent t-test was performed to detect the significant differences, and the Kolmogorov-Smirnov test was used for analysis (α=0.05). Results: No significant differences were found among the precision of marginal surface between the printed and milled crowns (p=0.181). The trueness of marginal and internal surfaces of the milled crowns were statistically higher than those of the printed crowns (p=0.024, p=0.001; respectively). Conclusion: The accuracy of provisional crowns manufactured using a milling machine and a 3D printer differed significantly except with regards to the precision of the internal surface. However, all the crowns were clinically acceptable, regardless of the manufacturing method used.

• Restorative Dentistry and Endodontics
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• v.44 no.3
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• pp.23.1-23.9
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• 2019

Objectives: The aim of this study was to investigate the microshear bond strength (${\mu}SBS$) of different universal adhesive systems applied to hybrid computer-aided design/computer-aided manufacturing (CAD-CAM) restorative materials repaired with a composite resin. Materials and Methods: Four types of CAD-CAM hybrid block materials-Lava Ultimate (LA), Vita Enamic (VE), CeraSmart (CS), and Shofu Block HC (SH)-were used in this study, in combination with the following four adhesive protocols: 1) control: porcelain primer + total etch adhesive (CO), 2) Single Bond Universal (SB), 3) All Bond Universal (AB), and 4) Clearfil Universal Bond (CU). The ${\mu}SBS$ of the composite resin (Clearfil Majesty Esthetic) was measured and the data were analyzed using two-way analysis of variance and the Tukey test, with the level of significance set at p < 0.05. Results: The CAD-CAM block type and block-adhesive combination had significant effects on the bond strength values (p < 0.05). Significant differences were found between the following pairs of groups: VE/CO and VE/AB, CS/CO and CS/AB, VE/CU and CS/CU, and VE/AB and CS/AB (p < 0.05). Conclusions: The ${\mu}SBS$ values were affected by hybrid block type. All tested universal adhesive treatments can be used as an alternative to the control treatment for repair, except the AB system on VE blocks (the VE/AB group). The ${\mu}SBS$ values showed variation across different adhesive treatments on different hybrid CAD-CAM block types.

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.3
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• pp.279-285
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• 2017

Defects due to mandibulectomy often cause hard and soft tissue loss and result in esthetic problems and functional disorders such as mastication, swallowing, and pronunciation. After the mandibular reconstruction, several complications including loss of alveolar bone can cause limitations in maintenance or supporting of removable prosthesis. For these patients, implant-supported fixed restorations have been an appropriate prosthetic restorative method. In this case report, we report the patient who underwent mandibulectomy and mandibular reconstruction owing to oral cancer, and then restored the current dentition functionally and aesthetically by applying zirconia frameworks and monolithic zirconia crowns by computer-aided design and computer-aided manufacturing.

• Journal of Korean Dental Science
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• v.15 no.2
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• pp.166-171
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• 2022

This case report describes a dynamic digital esthetic rehabilitation procedure that integrates a new three-dimensional augmented reality (3D-AR) technique to treat a patient with multiple missing anterior teeth. The prostheses were designed using computer-aided design (CAD) software and virtually trialed using static and dynamic visualization methods. In the static method, the prostheses were visualized by integrating the CAD model with a 3D face scan of the patient. For the dynamic method, the 3D-AR application was used for real-time tracking and projection of the CAD prostheses in the patient's mouth. Results of a quick survey on patient satisfaction with the two visualization methods showed that the patient felt more satisfied with the dynamic visualization method because it allowed him to observe the prostheses directly on his face and be more proactive in the treatment process.

• The Journal of the Korean dental association
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• v.56 no.11
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• pp.622-630
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• 2018

For successful surgery-first approach, accurate prediction of skeletal and dental changes following orthognathic surgery is essential. With recent development of digital technology using computer-aided design/computer-aided manufacturing (CAD/CAM) technology, attempts to provide more predictable orthodontic/orthognathic treatment have been made through 3D virtual surgery and digital tooth setup. A clinical protocol for the surgery-first orthognathic approach using virtual surgery is proposed. A case of skeletal Class III patient with facial asymmetry treated by the surgery-first approach using digital setup and virtual surgery is presented. Advantages and limitations of applying CAD/CAM technology to orthognathic surgery are discussed.

• Journal of Technologic Dentistry
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• v.42 no.3
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• pp.228-233
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• 2020

Purpose: This study aimed to assess and compare the marginal fit of ceramic-based hybrid resin restoration (HYB) and zirconia restoration (ZIR) for dental computer-aided design/computer-aided manufacturing systems. Methods: A stainless steel master model was produced. The impression was first made with silicone, and then stone working models were produced. A total of twenty restorations were fabricated with two different materials: ZIR and HYB. The silicone film thickness of the marginal gap was measured using a digital microscope; digital photos were taken at a magnification of ×160, and then analyzed using a measurement software. The values of the result were evaluated with the independent-sample t-test (α=0.05). All statistical analyses were performed with a statistical software. Results: The mean values for the marginal gap was 37.14±2.96 ㎛ for HYB, compared with 40.37±5.26 ㎛ for ZIR. No significant difference was found between ZIR and HYB (p=0.107). Conclusion: As a result, the marginal fit of the restoration fabricated using the hybrid resin was better than that of the restoration fabricated using zirconia. Also, the marginal fit of all groups was below the clinical acceptable range of 120 ㎛. Thus, HYB for dental CAD/CAM system in this study is expected to be suitable for clinical use in dentistry.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.3
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• pp.234-238
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• 2016

Purpose: Increasing use of computer aided design-computer aided manufacturing (CAD-CAM) system and number of design software made design of restoration easy and quick. Outcome of restoration has been dependent on dental technician's wax up proficiency, dentists can design restoration for themselves now. This study aims to investigate the outcome of restoration designs, according to handling skill of CAD-CAM design tool. Materials and methods: A patient's mandibular right 1st molar was prepared. After taking impression, stone model was made, scanned the stone model with 3 shape intra-oral scanner, stereolithography (STL) file was extracted. With 3shape dental designer, one dental technician with more than 5 years work experience (designer 0) and three dental technicians with less than 2years work experience (designer 1, 2, 3-group DT) and 4 1st year residents (designer 4, 5, 6, 7-group RT) designed gold crown on the same STL file. Designed crown's MD (mesio-distal) and BL (bucco-lingual) diameter, height of crown, inter-cuspal distance, number of occlusal contact points were compared. Statistical analysis was carried out, test of normality within each group, using independent t-test. Number of contact points were compared, using Wilcoxon signed-rank test. Results: There was no significant difference between group DT and group RT. Number of contact points also resulted in no significant difference. Conclusion: The outcome of each designed crowns showed no statistical differences, in values which can be expressed as numbers. Subjective factors were different. With increasing proficiency in handling designing software, fabrication of restorations according to each designer's occlusal concept can be made easy.

• Journal of Dental Rehabilitation and Applied Science
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• v.36 no.2
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• pp.128-137
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• 2020

Over the last 30 years, the use of chairside computer-aided design (CAD) and computer-aided manufacturing (CAM) systems has evolved and has become increasingly popular in dentistry. Although CAD/CAM restorations have been used in the anterior dentition, satisfying the esthetic requirements of clinicians and patients, where the restorations are limited to the chairside, remains a challenge. To reproduce multi-shades of CAD/CAM restorations in the clinic, a preliminary experiment to express several shades on A2 lithium disilicate (LS2) blocks using a staining kit was performed. After measurement of the CIE L^*a^*b^* value of specimens, it was compared with that of the commercial shade guide. This report presents two cases with individual customization of shade and surface characterization of the CAD/CAM restorations using predictable methods based on the preliminary experimental data. The anatomical shape of restoration was obtained from 'copy and paste technique' and 'mirror image acquisition technique'. All treatment procedures and fabrication of restorations performed in this report were executed in the clinic itself.

• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.1
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• pp.45-49
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• 2015

In this clinical report, a simple and convenient conversion of a fractured metal-ceramic surveyed crown into a complete contour zirconia surveyed crown by using computer-aided design and computer-aided manufacturing technology for an existing partial removable dental prosthesis is described. The duplication of the original contours, morphology, and the rest seat of the existing metal-ceramic surveyed crown, into a complete contour zirconia surveyed crown under anticancer treatments were reported.