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Objectives: This study aimed to evaluate the color stability of glaze‐coated 3D‐printed resin materials stored in different nutritionally beneficial smoothies that are commonly consumed. Methods: Disc‐shaped (27 × 1 mm) specimens were fabricated from tooth‐colored 3D‐printed dental resins with different indications: Arma Resin (Group A), VarseoSmile Crown Plus (Group B), Flexcera Smile Ultra+ (Group E), Formlabs Permanent Crown (Group F) ( n = 10 per group). After post‐processing and cleaning, all specimens received a standardized nano‐filled, light‐polymerized glaze coating. Water contact angle and roughness values were measured. The specimens were immersed in artificial saliva as control (AS) and three smoothies (green [G], orange [O], and purple [P]) for 30 days. pH and °Brix levels of beverages were recorded. Reflectance spectra were recorded using UV–Vis–NIR spectrophotometer and converted to color coordinates. Color differences ( and ) were calculated. Surface roughness and contact angle data were analyzed using two‐way ANOVA, while color change data were analyzed using Welch's ANOVA and Games–Howell post hoc test ( α = 0.05). Results: Surface roughness was significantly affected by material type, while storage media had no significant effect. Contact angle values were significantly influenced by both material type and storage media. Significant differences in and were observed only between the orange smoothie subgroups and their corresponding artificial saliva controls in Groups B, E, and F. No significant differences were observed for Group A in orange smoothie or for the green and purple smoothie subgroups compared with their corresponding artificial saliva controls. Conclusion: Orange smoothie caused significantly greater color changes than artificial saliva in Groups B, E, and F, but not in Group A. This finding suggests that the discoloration susceptibility of specimens is strongly influenced by material composition and specific smoothie ingredients.

The surface characteristics of zirconia may influence both soft tissue response and bacterial colonization. This study evaluated the surface roughness and water contact angle of zirconia fabricated by additive manufacturing (material jetting, NPJ) and subtractive manufacturing (milling), and investigated human gingival fibroblast (HGF-1) viability and Streptococcus mutans (S. mutans) (ATCC 25175) adherence on these surfaces, as well as the possible correlation between roughness and bacterial adhesion. Sixty-four zirconia specimens (1 × 1 × 0.1 cm) were fabricated (n = 32 per group), sintered, and standardized by abrasive polishing. Surface roughness and contact angle were measured. Cell viability was assessed using an MTT assay at 24, 48, and 72 h. Bacterial adhesion was quantified after 24 and 48 h of incubation. Data were analyzed using two-way ANOVA, independent t-tests, and Pearson correlation (α = 0.05). No significant differences in HGF-1 viability were observed at 24 and 48 h; however, at 72 h, subtractively manufactured zirconia demonstrated higher cell viability than additively manufactured specimens (p < 0.001). S. mutans adhesion was significantly greater on additively manufactured zirconia at 24 h (p = 0.002), with no significant difference at 48 h. Manufacturing technique influenced surface properties and early bacterial adhesion. Both materials exhibited acceptable biocompatibility within the tested conditions.

This study aimed to investigate the effects of diode laser parameters on the thermal response and surface morphology of RBM (Resorbable Blast Media), SLA (Sandblasted, Large-grit, Acid-etched), and additively manufactured Ti6Al4V titanium surfaces, and to determine whether surface type influences heat distribution and integrity, which is clinically relevant in peri-implantitis treatment. A total of 144 titanium discs with three different surface treatments (RBM, SLA, and additively manufactured Ti6Al4V as the control group) were irradiated with a 940 nm diode laser at varying power levels (1 W, 2 W, 3 W), durations (30 s, 60 s), and modes (continuous, pulsed). Surface temperatures were recorded using thermal imaging. Morphological and elemental changes were evaluated via Scanning Electron Microscopy (SEM) and Energy-Dispersive X-ray Spectroscopy (EDS) analyses. A four-way Aligned Rank Transform Analysis of Variance (ART ANOVA) was used to analyze the effects of variables. Temperature increases were significantly influenced by all tested variables (p < 0.001). The RBM group exhibited the highest peak temperature (185 °C at 3 W pulsed mode, 60 s), while SLA surfaces consistently showed the lowest (39.9 °C at 1 W continius mode, 30 s). Pulsed mode and longer exposure times produced higher temperatures, except at 1 W, which resulted in the lowest temperature rise regardless of surface treatment. SEM images revealed mild surface alterations at higher power, with RBM exhibiting localized depressions and SLA displaying minor fragmentation of surface textures. EDS analysis indicated no major changes in elemental composition post-irradiation. The study highlights that different titanium surface types respond distinctly to diode laser irradiation, with RBM surfaces being more thermally reactive. Uniform laser protocols may not be appropriate for all implant surfaces. Careful consideration of power, duration, and surface characteristics is essential to avoid potential thermal damage during peri-implantitis treatment.

This study investigates the surface properties of zirconia fabricated via nano particle jetting (NPJ), a material jetting–based additive manufacturing (AM) technique, and compares them to conventionally milled (CM) zirconia following plasma surface treatment. AM zirconia discs were produced using a 3 mol% yttria-stabilized ZrO₂ slurry, while CM discs were prepared from semi-sintered blocks. Both sample types were sintered at 1500 °C, ground, and subjected to low-pressure, low-temperature air plasma treatment for 1 or 5 min. Initial grain sizes were 0.545 ± 0.211 μm for AM and 0.520 ± 0.214 μm for CM zirconia, and X-ray diffraction confirmed the preservation of the tetragonal phase after treatment. Surface roughness parameters remained within the nanometer range and were unaffected by plasma exposure. As-built water contact angles were 59.1° ± 8.6° for AM and 58.9° ± 9.0° for CM zirconia, indicating comparable inherent hydrophilicity. Plasma treatment effectively reduced carbon residues and enhanced surface wettability by lowering the contact angles to 14.5° ± 3.1° (AM) and 15.7° ± 2.2° (CM) after 1-min treatment. However, no significant differences were observed with longer treatment durations. The effect was sustained for at least 72 h in closed storage but reverted after 2 months in ambient conditions. Vickers hardness of AM zirconia was 1298 ± 13 HV1.0, which was lower than that of CM zirconia (1341 ± 8 HV1.0) and plasma treatment had no measurable effect on surface hardness. This is the first study to systematically compare NPJ-manufactured and milled zirconia under standardized plasma conditions. The findings demonstrate the feasibility of NPJ zirconia for dental applications and the potential of plasma surface modification to improve early-stage biological responses through enhanced wettability. Graphical abstract

This study investigates the impact of surface modifications on additively manufactured CoCr and Ti6Al4V dental alloys, focusing on surface properties. Thin film carbon (C) and gold (Au) coatings, as well as alkali‐heat treatment, were applied to the high‐ and low‐polished specimens. Scanning electron microscopy (SEM) showed that thin film coatings retained the underlying surface topography, while the alkali‐heat treatment induced distinct morphological changes. Energy‐dispersive x‐ray spectroscopy (EDS) analysis revealed that C‐coating enriched surfaces with C, and Au‐coating introduced detectable amounts of Au. Nevertheless, signs of coating delamination were observed in the high‐polished specimens. Alkali‐heat treatment led to the formation of a sodium titanate layer on Ti6Al4V surfaces, confirmed by sodium presence and Fourier transform infrared spectroscopy (FTIR) results showing carbonate bands. Surface roughness measurements with atomic force microscopy (AFM) showed that C‐coating increased surface roughness in both high‐ and low‐polished alloys. Au‐coating slightly increased roughness, except for low‐polished Au‐coated Ti6Al4V, where a decrease in roughness was observed compared to low‐polished bare Ti6Al4V, likely due to surface defects present in the latter resulting from the additive manufacturing process. Alkali‐heat treatment led to a pronounced increase in roughness for both alloys, particularly for Ti6Al4V. Both thin film coatings decreased the water contact angles in all specimens in varying magnitudes, indicating an increase in wettability. However, the alkali‐heat treatment caused a substantial decrease in contact angles, resulting in a highly hydrophilic state for Ti6Al4V. These findings underscore the substantial impact of surface modifications on additively manufactured dental alloys, potentially influencing their clinical performance.Research Highlights: Thin film coatings and chemical/heat treatment modify the surface properties of additively manufactured dental alloys. The surfaces of the alloys get rougher and more hydrophilic after alkali‐heat treatment. Thin gold coatings exhibit potential adhesion challenges.

Purpose: The aim of this study was to evaluate the impact of the print orientation of direct metal laser sintering (DMLS) posts and cores on the fracture resistance and failure patterns of endodontically treated mandibular premolar teeth.Materials and Methods: Sixty intact human mandibular premolars were endodontically treated. The teeth were then randomly divided into four groups (n = 15). Cobalt-chromium (Co-Cr) metal posts were fabricated by traditional casting (Group C), and DMLS method in 0-, 45-, and 90-degree print orientations (Group DMLS 0, Group DMLS 45, and Group DMLS 90). The posts and cores were cemented with composite resin cement and subjected to compression test at a crosshead speed of 1 mm/min. Data was analyzed by using one-way analysis of variance ANOVA and multiple comparison post hoc Tukey tests (a = 0.05). Specimens were viewed under a stereo microscope with x20 magnification to evaluate the fracture types.Results: No significant differences were found among the groups tested in terms of fracture resistance (p > 0.05). Group C and Group DMLS 0 group exhibited similar fracture patterns.Conclusions: It is possible to produce post and core restorations with the DMLS technique and use them clinically. Print orientation did not influence the fracture resistance. However, fracture patterns were different. Group C outperformed all DMLS groups in terms of fracture patterns.

The rehabilitation of an edentulous patient is getting complicated if the edentulous ridge is large and excessively defective. This clinical report describes the restoration of a severely resorbed maxilla of a 49-year-old male patient with a hybrid denture. The intermaxillary vertical occlusal distance was considerably increased due to resorption of alveolar ridge and tuber maxilla. An acrylic resin based implant retained hybrid denture was fabricated to compensate the increased vertical distance and decrease the weight of the prosthesis. After a follow-up period of 5 year it was noticed that the patient was satisfied with the functional and esthetic functions of the denture.

The aim of the study is to evaluate the effect of trichloroethylene (TCE) on the metal-ceramic bond of ‎additively manufactured and casting Co-Cr alloys. For this purpose, 84 disc-shaped (r=12 mm, h=1 mm) ‎specimens were prepared for two experimental groups (n=42) with different fabrication techniques; casting ‎and additively manufactured with Co-Cr. Before ceramic application, the disc specimens divided into two ‎subgroups (n=21): Casting and cleaned with TCE (CT), casting and not cleaned with TCE (C), additively ‎manufactured and cleaned with TCE (AT), additively manufactured and not cleaned with TCE (A). Ceramic ‎‎(h=4 mm, r=6 mm) was applied to the disc specimens (n=20) and their shear bond strength (SBS) was ‎measured. The surface morphology of disc (n=1; for each subgroup) specimens before and after TCE ‎application was analyzed with a scanning electron microscope (SEM). Results were statistically analyzed with ‎‎1-way ANOVA and the Bonferroni multiple comparisons tests (α=0.05). Significant differences were found in ‎SBS of the CT, C, AT, and A groups. CT group (21.74±1.66 MPa) showed a significantly higher SBS value ‎than the C (18.65±2.11 MPa), AT (19.07±1.75 MPa) and A (18.52±1.94 MPa) groups (p<0.001). In ‎conclusion the application of the TCE increased the metal-ceramic bond of casting Co-Cr alloy. Although the ‎results were not statistically significant the TCE also increased the bond of additively manufactured Co-Cr ‎alloy.

Purpose: To evaluate and compare the mechanical properties and ceramic bond of additively manufactured and milled dental zirconia materials.Materials and Methods: Disc (r = 10 mm, h = 2 mm) and bar (254 × 1. 2 mm) shaped milled (M group) (Nacera Pearl; Doceram) and additively manufactured (AM group) (NanoParticle Jetting; XJet, Carmel 1400) zirconia specimens were prepared for 2 experimental groups. Ceramic was applied to the disc specimens (h = 4 mm, r = 6 mm) (n = 9) and their shear bond strength (SBS) was measured. The surface morphology of disc specimens was analyzed with a scanning electron microscope (SEM). The Vickers microhardness (Vh), surface roughness (Ra), and three‐point flexural strength (FS) of bar specimens (n = 9) were measured. Results were statistically analyzed with Mann‐Whitney U‐test (α = 0.05).Results: Significant differences were found in FS and Vh values of the M and AM groups. M group (1501.4 ± 60.1 HV1) showed a significantly higher Vh value than the AM group (1169.2 ± 48.4 HV1) (p < 0.001). FS of the M group (1287.5 ± 115.2 MPa) exhibited significantly high value than the AM (1030.0 ± 29.2 Mpa) group (p < 0.001). Statistically, no significant differences were seen in SBS and Ra values of the M and AM groups.Conclusion: Within the limitations of this in vitro study, the manufacturing technique affected the mechanical properties of the zirconia materials. AM zirconia material showed lower Vh and FS values than M zirconia. Additionally AM zirconia demonstrated adequate bond strength with dental ceramic.