• The Journal of Korean Academy of Prosthodontics
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• v.62 no.1
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• pp.6-19
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• 2024

With the advancement of Computer-Aided Design/Computer-Aided Manufacturing (CAD-CAM) technology, fabrication of dentures using this technology has gained popularity. As one of CAD-CAM technologies, digital complete denture system has been introduced, which fabricates complete dentures using subtractive manufacturing of monolithic block containing both the color of a denture base and an artificial tooth. In this case, two pairs of upper and lower dentures were fabricated for two patients. Two pairs of complete dentures were fabricated for a 74-year-old male and a 73-year-old female respectively by conventional denture fabrication method and digital method of milling. To obtain a digital complete denture, monolithic block (Ivotion, Ivoclar Vivadent, Schaan, Liechtenstein) was chosen for the materials to fabricate the digital complete dentures. An individual tray was designed using CAD software and manufactured by 3D printing technique. The final impression and interocclusal relationship were recorded using the fabricated individual tray. The final impression was scanned, and the complete denture design and try-in denture were 3D printed using CAD-CAM software. Subsequently, the monolithic block was milled, and the final dentures were fabricated and tried on patients. Previously mentioned two patient cases compared and analyzed stability, fit, speaking, mastication, aesthetics, and patient satisfaction of two pairs of dentures: one fabricated using CAD-CAM system and the other using traditional methods. This was performed to evaluate and report the findings from both denture-making approaches.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.4
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• pp.242-248
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• 2022

Recently, through the development of CAD/CAM technology, it is also being used for fabricating dentures. Compared to conventional methods, when digital dentures are fabricated, the fabrication process is facilitated, and the number of visits to hospitals is reduced and errors are reduced. In this case, the vertical dimension was increased using a CAD program in a patient who needed vertical dimension recovery due to the use of old dentures, and the final denture was fabricated using a monolithic disc through the milling method. The centric relation was recorded using existing dentures, and using the information from the intraoral scan and the existing denture model scan, a trial denture was fabricated and delivered to the patient to evaluate the midline and occlusion. Based on the evaluation of the trial denture, the final denture was fabricated using a milling method and a monolithic disc, and the final denture showed satisfactory results functionally and aesthetically.

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.4
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• pp.394-402
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• 2017

Purpose: The purpose of this study is to evaluate the displacement of artificial tooth of monolithic complete denture manufactured by milling and 3D printing method in which the denture base and the artificial teeth are simultaneously made. Materials and methods: Twelve upper and lower complete dentures for each were made by milling and 3D printing method. Group Up and Group Lp are a group of upper and lower dentures made by printing, and Group Um and Group Lm are denture groups made by milling. Group Uc and Group Lc are is a group of finally designed upper and lower dentures respectively. Measurements were performed between both central incisors (AB, ab), both canines (CD, cd), both first molars (EF, ef), between an incisor and a first molar (AE, ae), and between incisor and lingual point (AG, ag) for each upper and lower denture. Results: AG and ag value between printed dentures and original ones as well as between milled dentures and original ones showed a statistically significant difference (One-way ANOVA, P<.05) in both lower and upper monolithic dentures. In the lower monolithic ones, ab, cd and ef value revealed a significant difference between Group Lp and Group Lm (One-way ANOVA, P<.05). Conclusion: Dentures made using milling or 3D printers revealed statistically significant difference compared with those of original data. However, it showed clinically very accurate reproducibility.

• The Journal of Korean Academy of Prosthodontics
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• v.61 no.4
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• pp.268-274
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• 2023

In this case, a CAD-CAM complete denture that can be easily remanufactured and reduced the number of visits was decided in consideration of the fact that it was difficult to visit the dental hospital and many existing dentures were lost because the patient was inpatient in a nursing hospital. In order to reflect the shape, vertical dimension, and maxillomandibular relationship of the existing provisional dentures adapted by the patient to the fabrication of the final denture, the existing provisional dentures were scanned and closed mouth impression was taken with the printed individual tray. After digital facebow transfer using UTS CAD and arranging artificial teeth in CAD software, the maxillary and mandibular complete dentures were fabricated by milling the denture base and artificial teeth at once with the monolithic disc.

• Journal of Dental Rehabilitation and Applied Science
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• v.39 no.3
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• pp.158-167
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• 2023

As digital technology has advanced in the field of dentistry, the use of computer-aided design/computer-aided manufacturing (CAD/CAM) has brought changes to the stages of dental treatment. The use of CAD/CAM technology in dental restoration offers clinical efficiency and convenience by reducing production time and appointment intervals, while also simplifying the fabrication process to reduce errors. In this case, digital replication and printing of temporary teeth were used to aid a patient with complex medical histories and physical disabilities. The final impression obtained with silicone impression material included information on the vertical dimension, centric relation, and the angle and length of the anterior teeth, which shortened the production time and appointment intervals and increased patient satisfaction. The final restoration was fabricated using milling and monolithic disc techniques, demonstrating appropriate stability, retention, and support, resulting in functional and aesthetic satisfaction.

• The Journal of Advanced Prosthodontics
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• v.15 no.1
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• pp.22-32
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• 2023

PURPOSE. Digital technology has enabled improvements in the fitting accuracy of denture bases via milling techniques. The aim of this study was to evaluate the trueness and precision of digital and analog techniques for manufacturing complete dentures (CDs). MATERIALS AND METHODS. Sixty identical CDs were manufactured using different production protocols. Digital and analog technologies were compared using the reference geometric approach, and the Δ-error values of eight areas of interest (AOI) were calculated. For each AOI, a precise number of measurement points was selected according to sensitivity analyses to compare the Δ-error of trueness and precision between the original model and manufactured prosthesis. Three types of statistical analysis were performed: to calculate the intergroup cumulative difference among the three protocols, the intergroup among the AOIs, and the intragroup difference among AOIs. RESULTS. There was a statistically significant difference between the dentures made using the oversize process and injection molding process (P < .001), but no significant difference between the other two manufacturing methods (P = .1227). There was also a statistically significant difference between the dentures made using the monolithic process and the other two processes for all AOIs (P = .0061), but there was no significant difference between the other two processes (P = 1). Within each group, significant differences among the AOIs were observed. CONCLUSION. The monolithic process yielded better results, in terms of accuracy (trueness and precision), than the other groups, although all three processes led to dentures with Δ-error values well within the clinical tolerance limit.

• The Journal of Korean Academy of Prosthodontics
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• v.62 no.2
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• pp.140-145
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• 2024

Removable partial denture wearers are exposed to the risks that remaining teeth get damaged by caries, attritions, erosion, and fracture. In the case of damaged abutment tooth which should fit to Removable partial denture (RPD), the fabrication of surveyed crown is followed by the making of RPD. However, making new denture takes a long time, and needs several processes and costs. Also, patients should get used to new denture. If other abutment teeth and edentulous ridges provide the existing denture with support, retention, and stability, use of existing denture is considered clinically acceptable. In this situation, fabricating retrofit crowns to an existing removable partial denture makes patient use existing denture, cuts costs, and reduces discomfort. In this case, severely worn teeth were restored using monolithic zirconia crown which fit to an existing removable partial denture by CAD-CAM. Moreover, support, retention, and stability of the denture were improved, and both doctor and patient were satisfied with the result.

• Journal of Korean Dental Science
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• v.10 no.2
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• pp.74-81
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• 2017

This report describes two cases of complete arch implant-supported restorations. The first patient had seven dental implants in each arch with monolithic zirconia frameworks. At four weeks' follow-up, the one-piece maxillary framework was fractured, which was re-designed and re-fabricated using laser-sintered cobalt-chrome alloy. The second patient had four implants in the mandible only. A mandibular monolithic zirconia framework and a maxillary conventional complete denture were fabricated and delivered. At five years' follow-up, the patient reported no significant discomfort. Careful consideration and monitoring of the status of antagonistic arches and stress distribution on zirconia frameworks were suggested for complete arch implant-supported fixed restorations.

• The Journal of Korean Academy of Prosthodontics
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• v.60 no.1
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• pp.100-109
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• 2022

Installation of dental implants at optimal angles and positions is critical in long-term stable implant-supported restorations. Surgery and prosthodontic procedures should be performed accurately as the treatment is planned. In this clinical case, Computer aided design and manufacturing technology was used not only to establish a precise surgical plan, but also to fabricate both provisional and definitive fixed prostheses. A surgical guide was designed to install the implants at proper positions for the definitive prostheses. The patient's esthetic information, which was necessary for the new provisional and definitive fixed prostheses, was obtained from the existing temporary dentures. Finally, the complete mouth fixed implant-supported rehabilitation using monolithic zirconia provided the patient with functionally and esthetically satisfactory prostheses.

• The Journal of Advanced Prosthodontics
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• v.13 no.5
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• pp.304-315
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• 2021

PURPOSE. Esthetic expectations have increased the use of polyetheretherketone (PEEK) clasps as alternatives to Cr-Co in removable partial dentures (RPDs). The objective of this study was to evaluate the retentive force and dimensional change of clasps with different thickness and undercut made from PEEK by the thermo-mechanical fatigue. MATERIALS AND METHODS. PEEK clasps (N = 48) with thicknesses of 1 or 1.50 mm and 48 premolar monolithic zirconia crowns with undercuts of 0.25 mm or 0.50 mm were fabricated. Samples are divided into four groups (C1-C4) and were subjected to 7200 thermal aging cycles (at 5 - 55℃). The changes in the retentive force and dimensions of the clasps were measured by micro-stress testing and micro-CT devices from five measurement points (M1 - M5). One-way ANOVA, paired t-test, two-way repeated ANOVA, and post-hoc tests were used to analyze the data (P < .05). RESULTS. The retentive forces of C1, C2, C3, and C4 groups in initial and final test were found to be 4.389-3.388 N, 4.67 - 3.396 N, 5.161 - 4.096 N, 5.459 - 4.141 N, respectively. The effects of retentive force of all PEEK clasps groups were significant decreased. Thermo-mechanical cycles caused significant dimensional changes at points with M2, M4, and M5, and abraded the clasp corners and increased the distance between the ends of the clasp, resulting in reduced retentive forces (P^* = .016, P^* = .042, P < .001, respectively). CONCLUSION. Thermo-mechanical aging decreases the retentive forces in PEEK clasps. Increasing the thickness and undercut amount of clasps decreases the amount of dimensional change. The values measured after aging are within the clinically acceptable limits.