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Evaluation of blue-light model scanner trueness, precision, and surface detail reproduction with different rubber impression material colors

2026-03-16T01:53:58Z

Title: Evaluation of blue-light model scanner trueness, precision, and surface detail reproduction with different rubber impression material colors Authors: Seo, Kyoungjin; Cai, Hongxin; Shin, Seung-Ho; Choi, Ji-Won; Seo, Young-Bin; Kim, Jong-Eun; Kim, Kwang-Man; Jiang, Heng Bo; Kwon, Jae-Sung Abstract: Objective Although the accuracy of scanning technologies has been extensively explored, a research gap still exists concerning the scanning results of dental impression materials, particularly regarding their color and gloss characteristics. This study aims to evaluate and compare the scanning capabilities of blue-light scanners for various dental impression materials characterized by different colors and gloss levels. Methods Blue (B), green (G), red (R), and yellow (Y) dental impression materials were selected for this study. Colorimetric analyses were conducted using a spectrophotometer. The gloss levels of the samples were quantified using a gloss meter. The accuracy and surface detail reproduction of a blue-light scanner were analyzed by scanning impression materials in four different colors. The four-unit crown-bridge model for accuracy analysis was based on International Standardization Organization (ISO) standard 12836. The data measured by the coordinate measuring machine (CMM) served as the gold standard and were used for parameter comparison (height, angle, and distance) and 3D fitting with the scanned files. Results Surface detail reproduction analyses revealed significant differences among the various groups. Notably, Group B consistently demonstrated superior scanning accuracy across all measurements, indicating its effectiveness as a dental impression material in blue-light scanning applications. Significant differences were observed in the rate of surface detail, angle parameters, and corner height across the various groups (p < 0.05). Additionally, the root-mean-square error values pertaining to trueness exhibited significant disparities in all the specimens (p < 0.05). Significance. The absence of significant gloss differences across all color variations indicates that color should be evaluated alongside other critical factors when employing blue-light scanners for measurement accuracy.

Quantitative assessment of tooth wear using intraoral scanners: A comparative analysis of two monitoring tools

2026-03-16T04:50:16Z

Title: Quantitative assessment of tooth wear using intraoral scanners: A comparative analysis of two monitoring tools Authors: Higuera, Elizabeth Merino; Lee, Hyeonjong; Riera, Carme; Sailer, Irena; Ham, Sangmin; Zarauz, Cristina Abstract: Objectives: To evaluate the accuracy of a digital monitoring tool integrated in two intraoral scanners (Trios 3 and Trios 4) in detecting and quantifying tooth wear, using a validated ISO-based reference standard. Methods: An in vitro model was developed with a structured digital reference design incorporating vertically embedded slot structures to enable standardized sectioning and reduce operator variability. The Patient Monitoring Tool within the 3Shape IOS software was assessed by comparing its measurements to those obtained using a validated method conforming to ISO 20,896-1 Annex C. Tooth wear of varying depths (ranging from shallow to advanced) was simulated and measured across both systems. Measurement differences were statistically analyzed for accuracy evaluation. Results: The monitoring tool demonstrated clinically acceptable levels of accuracy in assessing moderate to advanced wear depths. However, the tool showed increased variability and decreased precision at lower wear levels, indicating limitations in detecting early-stage tooth wear. Conclusions: Intraoral scanner-based monitoring using the 3Shape Patient Monitoring Tool is a promising noninvasive method for longitudinal tooth wear assessment. Nevertheless, clinicians should interpret early wear measurements with caution due to limited accuracy in shallow wear detection. Further improvements in digital tool sensitivity are warranted to enhance early diagnostic capability. Clinical Significance: This study highlights the clinical potential of intraoral scanner-based monitoring for tooth wear. While effective in detecting advanced wear, clinicians should interpret minimal changes with caution. Understanding its limitations can aid in selecting appropriate tools for long-term, non-invasive wear assessment and early intervention in preventive and restorative dental care.

Comparative analysis of chemical properties and biocompatibility among high ceramic filler-based 3D printed resins, low filler-based 3D printed resins and CAD/CAM ceramics

2026-03-31T01:29:51Z

Title: Comparative analysis of chemical properties and biocompatibility among high ceramic filler-based 3D printed resins, low filler-based 3D printed resins and CAD/CAM ceramics Authors: Zhang, Zhihao; Lim, Jung-Hwa; Ma, Yifan; Chen, Di; Jin, Gan; Yim, Yeon-Woo; Lee, So-Hee; Kim, Jong-Eun Abstract: Objective This study aimed to compare surface properties, degree of conversion (DC), short-term eluate levels, and biocom-patibility between high-filler three-dimensional (3D) printed dental resins, low-filler 3D printed dental resins, and milled ceramic materials.
Materials and methods Two commercial high-filler 3D printed resins (containing zirconia and silica), one commercial low-filler 3D printed resin, one hybrid milled ceramic, and one zirconia milled ceramic were tested. The surface properties evalu-ated were degree of conversion (DC) (n = 10), contact angle and surface free energy (SFE) (n = 10), surface roughness using contact-type profiler (n = 10) and Atomic Force Microscopy (AFM, n = 1) and surface morphology using Scanning Electronic Microscopy (SEM, n = 1). Biocompatibility was assessed by measuring the viability (n = 10), proliferation (n = 3), and migra-tion (n = 6) of human gingival fibroblasts after exposure to material eluates. Eluates were analyzed subjectively using liquid chromatography-tandem mass spectrometry (n = 1). Data were analyzed statistically using one-way ANOVA with Tukey's HSD test (alpha = 0.05).
Results High-filler resins showed significantly higher DC than the low-filler resin (p < 0.05). Postcuring increased DC in the low-filler resin but not in high-filler resins. High-filler resins and the hybrid ceramic exhibited higher surface energy and lower contact angles than zirconia and the low-filler resin, while surface roughness was highest in the hybrid ceramic and lowest in the low-filler resin (p < 0.05). Eluates had no effect on viability or proliferation but significantly reduced fibroblast migration for the high-filler resins and hybrid ceramic (p < 0.05).
Conclusions High-filler 3D printed resins demonstrated higher DC and surface energy but released more residual monomers than the low-filler resin and ceramics. While eluates did not impair cell viability or proliferation, they reduced fibroblast migration, suggesting possible implications for soft-tissue healing.
Clinical relevance High-filler 3D printed resins exhibit acceptable biocompatibility with potential concerns regarding migration, making them potential alternatives to conventional milled ceramics in prosthodontics. However, the potential impact of released residual monomers on soft-tissue healing highlight the need for further optimization and long-term safety evaluations

Effect of scan body geometric configuration and library design on digital implant impression accuracy

2026-03-27T02:36:14Z

Title: Effect of scan body geometric configuration and library design on digital implant impression accuracy Authors: Moon, Hong Seok; Choi, Ahreum; Oh, Kyung Chul; Sun, Minji; Kim, Jaeyoung Abstract: PURPOSE. The purpose of this in vitro study was to evaluate how variations in scan body geometry, specifically body height and the length of the flat indexing surface (FIS), affect linear and angular accuracy when combined with truncated or full-geometry library files. MATERIALS AND METHODS. Nine scan body geometries were fabricated by combining three body heights (4, 5, and 6 mm) with three FIS lengths (1, 2, and 3 mm). Digital impressions were superimposed onto truncated or full-geometry library files. Linear deviation (Delta D) and angular deviation (Delta A) were calculated by comparing aligned scan bodies with coordinate measuring machine references. Linear and angular deviations were compared between library types using the Mann-Whitney U test, and differences among body heights and FIS lengths were evaluated using the Kruskal-Wallis test with Dunn's post-hoc test (alpha = .05).RESULTS. Linear deviation remained within a comparable range, and most geometry-library comparisons did not show a significant difference from body height, FIS length, or library morphology (P > .05). Angular deviation demonstrated geometry-dependent behavior, increasing only in the 4-mm body paired with larger FIS lengths, particularly when full-geometry libraries were used. No significant angular differences were observed in the 5-mm or 6-mm body groups. CONCLUSION Digital implant registration remained stable across most configurations. Shortened scan bodies performed reliably when FIS dimensions were preserved. Angular accuracy was more sensitive to geometry-library interactions, with truncated libraries improving stability.