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Purpose: This review aimed to classify and narratively synthesize the literature on digital complete dentures based on the manufacturing methods, structural types, tooth-base bonding strategies, and intended clinical applications. Methods: A semi-systematic literature review was conducted using the PubMed and RISS databases to identify relevant publications from January 2010 to March 2026. The records were screened using the predefined inclusion and exclusion criteria, organized with Zotero, and classified by study design, fabrication method, structural type, bonding strategy, application scope, and major research topic. Results: The included publications were classified into milling, 3D printing, and hybrid digital workflows and further into monolithic and separate base-and-teeth structures. Hybrid digital workflows were common and referred to as workflows combining different fabrication routes or component sources. Milling was mainly associated with definitive complete dentures, whereas 3D printing was reported across definitive, interim, and trial applications. Conclusion: Digital complete denture workflows should be interpreted not only by manufacturing principle but also by structural designs, bonding strategies, material characteristics, intended use, and maintenance requirements. Furthermore, these factors should be considered together in the clinical and laboratory decision-making process.

Purpose: This study aimed to evaluate and compare the marginal and internal fit of provisional dental prostheses fabricated using two different printing techniques with identical computer-aided design data and design parameters, as well as to assess their clinical applicability. Methods: A three-unit fixed dental prosthesis was designed using the maxillary right first premolar and first molar as abutments, with the missing right second premolar serving as a pontic. Based on the design, a negative mold was fabricated using silicone impression material, and dental stone was poured to create working models. Each model was scanned using a dental scanner, and a total of 20 specimens (10 per group) were fabricated from the resulting STL data. The fit of the specimens was assessed using the silicone replica technique and examined under an optical microscope at 12 measurement points, including the marginal area, axial wall, and occlusal surface. Statistical analysis was performed using an independent sample t-test (α=0.05). Results: Prostheses fabricated using the liquid crystal display (LCD) method demonstrated significantly smaller gap values at all measured sites compared with those produced using the digital light processing method (p<0.05). Although most gap measurements in both groups remained within the clinically acceptable limit of 120 μm, the LCD-fabricated restorations consistently demonstrated superior overall adaptation. Conclusion: The findings of this study indicate that the type of printing method significantly affects the fit of provisional restorations. For improved restoration accuracy, the use of the LCD printing method is recommended.

Purpose: To compare the trueness of liquid crystal display (LCD) 3D-printed orthodontic models generated from cone-beam computed tomography (CBCT) and an intraoral scanner (IOS) and assess their clinical applicability. Methods: A standardized dental master cast was digitized with a high-precision optical scanner to generate a reference standard tessellation language file. The cast was scanned 10 times using CBCT and 10 times using an IOS, and each dataset was used to print a model with an LCD 3D printer (n=20). After post-curing, all printed models were rescanned and compared with the reference data using 3D best-fit alignment. Root mean square (RMS) deviation values were calculated and analyzed using the Shapiro–Wilk test, Levene’s test, and an independent t-test (α=0.05). Results: The IOS group showed significantly lower RMS deviation than the CBCT group, with mean RMS values of 106.20±3.29 μm and 122.50±1.84 μm, respectively (p<0.001). Color difference map analysis showed a uniform green distribution across the surface in Group A. In contrast, Group B showed increased red areas on the buccal and lingual posterior surfaces and irregular blue areas on the occlusal surfaces. Conclusion: The accuracy of LCD 3D-printed orthodontic models was significantly affected by the data acquisition method, with IOS-derived models showing superior trueness compared with CBCT-derived models. However, both methods remained within clinically acceptable limits, supporting their use for orthodontic diagnosis and appliance fabrication.

Purpose: This study evaluated the effects of different heat-treatment temperatures on the surface hardness and bending fatigue characteristics of dental cobalt-chromium (Co-Cr) alloys fabricated using selective laser melting (SLM). Methods: Co-Cr alloy specimens fabricated by SLM were divided into four groups according to the heat-treatment temperature: Con, FT750, FT850, and FT950. Bending fatigue tests were performed under a cyclic load of 13 N at 5 Hz for 30,000 cycles. Surface hardness was measured using a Vickers hardness tester at six designated locations. Results: No fracture occurred in any group after 30,000 cycles. The FT950 group showed the highest displacement, whereas the FT750 group showed the lowest displacement. After heat treatment, surface hardness increased significantly, with the FT850 group showing the highest hardness value. Statistical analysis revealed significant differences among all groups (p<0.05). Conclusion: Heat treatment significantly affected the mechanical properties of SLM-fabricated Co-Cr alloys. The FT850 group exhibited the most favorable balance between hardness and fatigue resistance, suggesting that a heat-treatment temperature of 850°C may be considered a favorable condition for dental Co-Cr alloy frameworks in terms of hardness and deformation behavior.

Purpose: To assess the effects of different sterilization methods on the trueness and precision of 3D-printed surgical guides. Methods: In this study, surgical guides were 3D-printed using resin to facilitate the planned placement of a missing mandibular right second premolar in a training model. Sterilization was performed using hydrogen peroxide plasma (55℃ for 25 minutes) and autoclaving (132℃ for 20 minutes, followed by a 30-minute drying cycle). Each surgical guide was scanned, and the data were exported in standard tessellation language format. The root mean square (RMS) values were calculated using 3D superimposition software, with the original design file as the reference data and the scan file of the 3D-printed guide as the measurement data. Thirty surgical guides were divided into three groups (n=10): non-sterile, plasma sterilization, and autoclave sterilization. Statistical analyses of the extracted RMS values were conducted using ANOVA for trueness assessment and the Kruskal–Wallis test for precision evaluation. Results: In the trueness evaluation, no statistically significant differences in RMS values were observed among the non-sterile, plasma sterilization, and autoclave sterilization groups (p>0.05). In contrast, the precision evaluation revealed significant differences among the groups, with the plasma sterilization group showing the lowest RMS value. Color map analysis showed relatively greater localized internal surface deviations in the autoclave sterilization group, whereas the plasma sterilization group exhibited comparatively uniform internal surface stability. Conclusion: The internal trueness of the 3D-printed surgical guides did not differ significantly depending on the sterilization method; however, a significant difference in precision was observed.

Purpose: This study aimed to examine the association between smartphone use time and oral health behaviors among Korean adolescents and to investigate the mediating effects of mental health factors. Methods: Data from the 2025 Korea Youth Risk Behavior Survey (n=52,385) were analyzed. Smartphone use time was used as the independent variable, and the oral health behavior index (0~5) was used as the dependent variable. Multiple regression and bootstrap mediation analyses were conducted. Results: Longer smartphone use duration was significantly associated with poorer oral health behavior (β=–0.095, p<0.001). Adolescents with higher levels of smartphone use showed lower rates of tooth brushing, flossing, scaling, and dental check-ups. Stress, sleep insufficiency, and depressive experience exerted significant partial mediating effects, with depressive experience demonstrating the strongest indirect effect. Conclusion: Excessive smartphone use negatively affects oral health behaviors directly and indirectly through mental health factors.

Digital innovations have transformed removable partial denture (RPD) fabrication by improving precision, consistency, and efficiency. This report describes a mandibular Kennedy Class I RPD framework fabricated by computer-aided design (CAD) and masked stereolithography (MSLA) 3D printing. The mandibular cast was scanned, and the framework was digitally designed with a defined path of insertion, blockout, relief, and clasp and connector configurations. The resin framework was printed, post-cured, invested, and cast in cobalt– chromium alloy. The definitive prosthesis showed clinically acceptable adaptation, retention, and functional stability without patient discomfort. This MSLA-based workflow reduced human error, shortened fabrication time, and reproduced anatomical details accurately. The case demonstrates the clinical feasibility and advantages of integrating CAD and 3D printing into RPD fabrication as a predictable alternative to conventional lost-wax techniques.