The aim of this study was to determine the effects of glass and polyethylene fibers on the color and translucency change of bulk-fill and anterior composites before and after artificial accelerated aging (AAA). Two types of teflon molds were used to fabricate samples which were 13 mm in diameter and, respectively, 2 mm and 4 mm in height. Polyethylene fiber (PF) and glass fiber (GF) were incorporated in the middle of the composite samples. Color and translucency changes of each composite were evaluated before and after AAA with spectrophotometer. ANOVA and Tukey’s HSD post hoc statistical analysis were used at a significance level of 0.05. Before AAA (for anterior composites), there were no significant differences in L* and b* parameters among the three groups (p>0.05); there were no significant differences in L* parameter between PF and GF groups or in TP between GF and control groups (p>0.05) (for bulk-fill composites). After AAA, there were no significant differences in L* parameter between GF and control groups, in a* parameter between PF and control groups, in b* parameter among all groups, or in TP parameter between GF and control groups (p>0.05). Fiber reinforcement led to color and TP change in both anterior and bulk-fill resin composites.

To digitally evaluate the trueness and fit of additively and subtractively manufactured fixed complete dentures in materials intended for definitive use. An edentulous maxillary model with implants at the left first molar, left canine, right canine, and right first molar site was digitized and a fixed complete denture was designed. This design was used to fabricate fixed dentures in an additively manufactured resin for definitive use (AM), a high-impact polymer composite (SM-CR), and a strength gradient zirconia (SM-ZR) (n = 10). Each fixed denture was digitized and the surface (overall, occlusal, except occlusal, and abutments), linear, and interimplant distance deviations were analyzed. The fit was assessed with the triple-scan protocol. Data were analyzed with Welch analysis of variance and Games-Howell tests (α = 0.05). SM-ZR led to lower overall deviations than AM, which had the highest occlusal and the lowest abutments deviations (P ≤ 0.007). SM-ZR had the lowest occlusal and SM-CR had the highest except occlusal deviations (P ≤ 0.002). AM mostly had higher linear and SM-CR mostly had higher interimplant distance deviations (P ≤ 0.043). AM led to the highest marginal gap at the left canine site, while SM-CR had the highest and SM-ZR had the lowest gaps at the right canine site (P ≤ 0.022). SM-ZR dentures mostly had trueness and marginal fit similar to or better than the other groups. Tested fixed complete dentures were mostly smaller than the design file in terms of interimplant distances.

The knowledge on the surface deviations and wear of recently introduced additively or subtractively manufactured materials indicated for definitive prosthesis is limited. The aim of this present study was to evaluate the external surface and mesiodistal width deviation and the occlusal surface wear of one additively manufactured composite resin (MS) and three subtractively manufactured resins (nanographene-reinforced polymethylmethacrylate (GR), conventional polymethylmethacrylate (PMMA), and reinforced composite resin (BC)) after thermomechanical aging. Molar-shaped crowns were fabricated in the tested materials and digitized with an intraoral scanner (CEREC Primescan; Dentsply Sirona, Bensheim, Germany). Each crown was subjected to thermomechanical aging and rescanned with the same scanner. A three-dimensional analysis software (Geomagic Control X v.2022.1; 3D Systems, Rock Hill, SC, USA) was used to calculate the deviations on the external surface, mesiodistal width, and wear on the occlusal surfaces of the tested crowns. Data were analyzed using one-way ANOVA and Tukey’s tests (α = 0.05). MS had higher external surface deviations than PMMA and GR (p ≤ 0.038) and higher mesiodistal width deviations than PMMA and BC (p = 0.004). BC and GR had higher volume loss than PMMA (p ≤ 0.002). The additively manufactured composite resin was more prone to deviations, while reinforced composite resin had lower wear resistance than most of the tested materials.

Purpose: To evaluate how build orientation affects the fabrication trueness of additively manufactured implant‐supported complete arch prostheses by comparing them to subtractively manufactured high‐impact polymer‐based prostheses.Materials and Methods: An edentulous maxillary model with four implants at canine and first molar regions bilaterally was digitized (ATOS Core 80 5MP) to design a reference implant‐supported complete arch prosthesis standard tessellation language file (RF‐STL). The STL file was used to manufacture prostheses additively in five different orientations according to the build platform (AM‐0, 0‐degree; AM‐15, 15‐degree; AM‐30, 30‐degree; AM‐45, 45‐degree; AM‐90, 90‐degree) or subtractively (SM‐HIP, control) (n = 10). The prostheses were digitized with an intraoral scanner (Trios 3) to generate their STLs (TF‐STL). After superimposing TF‐STLs over the RF‐STL with a metrology‐grade analysis software program (Geomagic Control X), surface deviations at four regions (overall, occlusal, overall without occlusal, and abutments), linear deviations at each abutment site, and interimplant distance deviations (canine‐to‐molar, canine‐to‐canine, and molar‐to‐molar) were calculated. One‐way analysis of variance and Tukey HSD tests were used for the statistical analyses (α = 0.05).Results: AM‐90 mostly had the highest surface deviations, while AM‐0 had the lowest overall, and lowest overall without occlusal region deviations (p ≤ 0.022). SM‐HIP had the lowest occlusal region deviations (p < 0.001). AM‐90 had the highest linear deviations (p < 0.001). AM‐15 had higher canine‐to‐molar deviations than SM‐HIP (p = 0.042). SM‐HIP had the highest canine‐to‐canine deviations, while AM‐90 had higher deviations than AM‐0 and AM‐30 (p ≤ 0.026). AM‐45 and AM‐90 had the highest and AM‐0 had the lowest molar‐to‐molar deviations (p ≤ 0.013).Conclusions: AM‐0 mostly had higher trueness and AM‐90 mostly had lower trueness within tested outcomes. Additively manufactured prostheses mostly had lower canine‐to‐molar distances and higher molar‐to‐molar distances, whereas SM‐HIP prostheses consistently had higher distances than the design file.