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Purpose: To evaluate the effect of three different curing protocols based on different ratios of self-curing and light-curing periods on the bond strength and nanoleakage of fiber posts luted with dual-curing selfadhesive cements. Materials and Methods: A total of 48 single-root teeth were endodontically treated and obturated, and an 8-mm post space was prepared with dedicated drills. Specimens were randomly divided into two groups according to the self-adhesive cement employed: group 1 (G1) = PANAVIA SA Plus (Kuraray Noritake), and group 2 (G2) = Bifix SE (VOCO). The specimens were further divided into three subgroups (n = 8 each) according to the light-curing protocol applied: no light-curing (SG1), 20 seconds of light-curing 20 seconds after cement injection (SG2), and 20 seconds of light-curing 120 seconds after cement injection (SG3). Slices of 1-mm thickness were prepared for the pushout test and nanoleakage analyses of the coronal and apical regions after 24 hours of storage in artificial saliva. Results were statistically analyzed with threeway ANOVA and Tukey post hoc tests. Statistical significance was set for P < .05. Results: Three-way ANOVA analysis showed that the factors of cement (P = .02) and curing protocol (P < .001) had a significant influence on bond strength. Tukey post hoc test reported that light-curing 120 seconds after injection showed higher bond strength compared to both no light-curing and photoactivation after 20 seconds. Conclusion: To achieve the highest bond strength with self-adhesive cements, photoactivation with a 120-second delay after mixing is required. There is no difference between light-curing immediately and light-curing 20 seconds after mixing. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the fracture strength of endodontically treated molars filled with different composite resins with vs without fiber reinforcement. Materials and Methods: A total of 60 intact mandibular molars were selected and endodontically treated. A standardized mesio-occlusal-distal cavity was prepared with cervical margins 1 mm above the cementoenamel junction and oral and buccal walls with 1.5-mm thickness. Universal adhesive was used in all specimens in etch-and-rinse mode. Specimens were divided into four groups (n = 15 each) according to restoration technique: group CSM = adhesive overlay with hybrid ceramic; group EXP = direct restoration with short fiber-reinforced composite; group ESU = direct restoration with nanohybrid composite; and group EST = direct restoration with nanohybrid composite reinforced with horizontal bidirectional glass fibers placed over the pulpal chamber floor. After 7 days of storage in water, samples were loaded until fracture using a universal testing machine. The maximum breaking loads were recorded in Newtons, and statistical analysis was then conducted with two-way ANOVA and post hoc Tukey test. Fragments were analyzed using scanning electron microscopy. Results: Mean fracture resistance values were: CSM = 1,428.91 ± 316.90 N; EXP = 1,874.57 ± 299.47 N; ESU = 1,557.44 ± 355.65 N; and EST = 1,870.27 ± 145.11 N. The CSM and EXP groups showed the highest strength values when compared to the other groups. The variable fiber insertion did not significantly alter the fracture resistance. The origin of the fracture was always located on the occlusal surface, mainly in the major contact loading area. Conclusion: The use of fiber-reinforced composite showed great improvement in fracture resistance, similar to a cuspal coverage restoration. However, only short fiber-reinforced composites showed a favorable fracture pattern. [ABSTRACT FROM AUTHOR]

Aim: To investigate the bidirectional influence between periodontitis and psoriasis, using the respective experimental models of ligature‐ and imiquimod‐induced diseases on murine models. Materials and Methods: Thirty‐two C57/BL6J mice were randomly allocated to four experimental groups: control (P− Pso−), ligature‐induced periodontitis (P+ Pso−), imiquimod‐induced psoriasis (P− Pso+) and periodontitis and psoriasis (P+ Pso+). Samples (maxilla, dorsal skin and blood) were harvested immediately after death. Measures of periodontitis (distance between the cemento‐enamel junction and alveolar bone crest [CEJ–ABC] and the number of osteoclasts) and psoriasis (epidermal thickness and infiltrate cell [/0.03mm2]) severity as well as systemic inflammation (IL‐6, IL‐17A, TNF‐α) were collected. Results: The P+ Pso+ group exhibited the most severe experimental periodontitis and psoriasis, with the highest values of CEJ–ABC, number of osteoclasts, epidermal thickness and infiltrate cells in the dorsal skin, as well as the highest blood cytokine concentration. The P+ Pso− group presented with higher cell infiltrate (/0.03mm2) compared to the control group (p <.05), while the P− Pso+ group showed substantially higher alveolar bone loss (CEJ–ABC) than the control group (p <.05). Conclusions: Experimental periodontitis may initiate and maintain psoriasiform skin inflammation and, vice versa, experimental psoriasis may contribute to the onset of periodontitis. In a combined model of the diseases, we propose a bidirectional association between periodontitis and psoriasis via systemic inflammation. [ABSTRACT FROM AUTHOR]

Objectives: To conduct a systematic review on the translucency of bulk‐fill (BF) composite materials, evaluating the factors influencing it and its clinical implications. Materials and Methods: A systematic search was performed on four databases (Embase, Medline/PubMed, Scopus, and Web of Science) for articles published until October 2, 2023. Search terms were: "translucency," "translucency parameter," "contrast," "contrast ratio," "bulk," "bulk‐fill," "bulk fill," "composite," "resin," "resin based," "resin‐based," "restoration," and "dental." In vitro studies, written in English language, investigating BF resin‐based composites translucency were included. The risk of bias was performed with the RoBDEMAT tool. Results: Of 590 screened articles, 13 were included in this review. They investigated 11 high‐viscosity BF and 5 low viscosity ones. The limited number of the identified studies and the heterogeneity of the extracted data did not allow to conduct a meta‐analysis. Conclusions: BF materials exhibit variability in translucency due to variations in experimental designs and the heterogeneous composition. Clinical Significance: BFs may behave differently in masking the substrate or in blending capacity. [ABSTRACT FROM AUTHOR]

Purpose: To three-dimensionally evaluate the interfacial gap of bulk-fill resin composites applied in deep Class-I restorations with different layering techniques and curing modes. Materials and Methods: Ninety-six (n = 96) samples were prepared with standardized deep Class-I cavities and adhesive procedures. Four materials were tested: SDR (SDR), SonicFill2 (SF), Admira Fusion X-Tra (AFXT), Filtek Supreme XTE (FS). Four subgroups (n = 6) were created according to layering and curing techniques: 2+2mm increments with soft start curing (SG1), 2+2 mm with conventional curing (SG2), a 4-mm increment with soft start curing (SG3), a 4-mm increment with conventional curing (SG4). All samples underwent micro-CT scans; afterwards, voids surrounding the restorations automatically underwent a thresholding procedure (Mimics, Materialise; Geomagic Studio 12, 3D Systems) to analyze the 3D interfacial gap. Statistical analysis was performed using three-way ANOVA with Tukey’s test (significance p < 0.05). Results: Statistically significant differences were reported between materials, layering techniques and their interaction. No statistically significant differences were reported for polymerisation mode. Bulk-fill materials showed average interfacial gap volumes ranging from 0.031 mm³ to 0.200 mm³, while FS showed volumes ranging from 0.416 mm³ to 1200 mm³. Conclusions: All bulk-fill materials performed statistically significantly better than did FS (p < 0.05), with no statistically significant differences between them. Curing mode did not influence interfacial gap volume in any group (p > 0.05), while bulk-filling vs layering influenced the volume of interfacial gaps only in the FS group, which performied better when incrementally applied. Regarding gap localisation, the floor of the cavity was the area with the highest likelihood of gaps in all samples. [ABSTRACT FROM AUTHOR]