Objectives:The purpose of this study was to evaluate the effect of the pre-conditioning step using different dentin conditioners on the shear bond strength (SBS) of the nano-filled resin-modified glass ionomer (RMGI) to dentin.Methods:Twenty-four human molars were used in this study. Subsequent to teeth sectioning in the mesio-distal direction and creation of the smear layer, the teeth were divided into six groups with and without the pre-conditioning step. Dentin surfaces were restored with RMGI cylinders and the specimens were stored in distilled water at 37ºC for 24 hours. SBS test were performed using a Universal Testing Machine at a crosshead speed of 0.5 mm/minute. Statistical analysis was performed using One-Way ANOVA followed by Duncan’s Multiple Range Test. RMGI/dentin interface was evaluated using SEM operated at 12 Kv at 2000X magnification.Results:35% phosphoric acid and EDTA yielded significantly higher SBS (12.0±1.8 and 11.9±4.4 MPa, respectively), compared to all tested groups. In addition, 25% polyacrylic acid (8.6±3.1 MPa) reported significantly higher SBS than the nano-filled RMGI when applied according to manufacturer instructions (5.5±2.2 MPa). When nano-filled RMGI was applied without its nano-primer, or directly over 25% polyacrylic acid conditioned dentin exhibited 100% pre-test failure, and their SBS were expressed as 0.0±0.0 MPa. SEM revealed that the nano-primer was unable to decalcify and hybridize the dentin surface.Conclusions:Based on the results of the current study, the pre-conditioning step effectively improves the SBS of nano-filled RMGI to dentin. The self-adhesiveness of nano-filled RMGI was not proved in this study.

A ''sandwich technique'' restoration using nano-filled RMGI/resin composite can be achieved in one clinical bonding step using the self-etch adhesives. SUMMARYObjective: To investigate the shear bond strength of the nano-filled resin-modified glass ionomer (RMGI) to dentin using different selfetch adhesives.Materials and Methods: Two resin-based restorative materials, a nano-filled RMGI (Ketac Nano-100, 3M ESPE) and a restorative composite (Grandio, VOCO) were bonded to bovine dentin using four self-etch adhesives (Futurabond M, VOCO; Adper Easy Bond, 3M ESPE; G Bond, GC Corp; and One Coat, Coltène). One hundred bovine anterior teeth were used in this study. Subsequent to labial enamel removal, each adhesive was applied according to manufacturer instructions. Fifty teeth were restored with the nano-filled RMGI and the other 50 were restored with the resin composite. Cylinders of 332 mm from the two restorative materials were bonded to dentin, and the specimens were stored in distilled water for 24 hours. Shear bond strength testing was performed in a universal testing machine at a crosshead speed of 0.5 mm/min. Two randomly selected specimens from each group were chosen for evaluation by scanning electron microscopy (SEM). Failure modes were evaluated using the stereomicroscope. All data for shear bond strength in MPa were expressed as mean 6 standard deviation (SD). Statistical analysis was carried out using SAS program (SAS, 1988).Results: Two-way analysis of variance revealed that the adhesives, the restorative materials, and their interactions (adhesives and restorative materials) had a significant effect on the shear bond strength to bovine dentin.Conclusions: Self-etch adhesives used in this study can adequately bond the nano-filled RMGI to dentin.

Abstract:We evaluated the effects of air-drying distance and bond surface area on the shear bond strength of a 2-step etch-and-rinse adhesive. A total of 120 bovine anterior teeth were equally divided into 6 main groups based on bonding surface area. The main groups were divided into sub-groups (n = 5) according to air-drying distance. The shear strength was determined using a universal testing machine at a crosshead speed of 0.5 mm/min. The averaged results were subjected to two-way ANOVA and Tukey's test (α = 0.05). Two-way ANOVA testing identified no significant cross-product interactions (p > 0.05), but the main factors of area (p < 0.0001) and air-drying distance (p < 0.00001) significantly affected the mean bond strength. Shorter air-drying distances improved bond strength, and increased surface area decreased the bond strength.

Background Rotator cuff tendinopathy (RCT) is a leading cause of shoulder pain and disability. Management is mainly conservative, but the limited ability of tendons to regenerate is the main cause of unsatisfactory results. So, we conducted our study to compare the efficacy of deep prolotherapy (glucose 25%), platelet-rich plasma (PRP), and betamethasone corticosteroid for treatment of RCT to find the most effective one based on clinical, functional, and radiological assessment. Results Regarding visual analog scale (VAS), it was significantly (p < 0.001) improved after injection among group 1 (prolotherapy group) and group 3 (steroid group) patients, while no significant improvement was noted among group 2 (PRP group) (p = 0.212) patients. The Western Ontario Rotator Cuff (WORC) Index significantly improved among the studied groups (p < 0.001, p = 0.049, and p < 0.001, respectively) after injection. Regarding the range of motion (ROM), a significant improvement (p = 0.029) was achieved in group 1 after injection but no significant improvements were noted among group 2 and 3 patients (p = 0.529 and 0.121, respectively). There was a significant improvement among group 1 and 2 patients (p < 0.001 and p = 0.020, respectively) regarding the grade of tendon lesions but no improvement occurred among group 3 patients (p = 0.470). Conclusion Prolotherapy injections improve shoulder ROM, VAS, WORC index, and rotator cuff tendon healing while PRP injections improve WORC index and tendon healing but steroid injection has no effect on healing. Trial registration PACTR202005610509496. Retrospective registration on May 25, 2020, Pan African Clinical Trial Registry.

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