Clinical behavior of universal adhesives in non-carious cervical lesions: A randomized clinical trial.

OBJECTIVES: This randomized, double-blind clinical trial, , evaluated the behavior of two universal adhesives used in etch-and-rinse (ER) or self-etch (SE) approach in non-carious cervical lesions (NCCLs). METHODS: Two hundred and eleven NCCLs were selected in 54 participants and randomly allocated into four experimental groups: Scotchbond Universal Adhesive - SBU (3M Oral Care) and Prime & Bond Elect - PB (Dentsply Sirona) used in ER and SE modes. Two trained operators placed all resin composite restorations (Filtek Z250, 3M Oral Care). Restorations were evaluated at baseline and after 6 months using both FDI and USPHS modified criteria by a blinded calibrated examiner. Kruskal-Wallis and Mann-Whitney U non-parametric tests were used to compare the restoration failures among experimental groups. RESULTS: Statistically significant differences were found among groups regarding failures (p=0.000 for both FDI and USPHS criteria). PB-SE presented more failures (p<0.05) than other experimental groups. No significant difference was found between any other pair of groups (p>0.05). CONCLUSIONS: The etch and rinse approach affected the clinical performance of Prime and Bond Elect. For this material, the self-etch approach generated lower criteria scores after a six-month follow-up. The bonding strategy did not influence Scotchbond Universal Adhesive clinical performance. (RBR-2GQMVF) CLINICAL SIGNIFICANCE: The clinical behavior of mild universal adhesive Prime & Bond Elect depends on the bonding strategy. The etch-and-rinse approach is recommended for this adhesive system. Scotchbond Universal Adhesive can be used in both bonding strategies without impairing clinical performance.

Incorporation of nanocapsules into gellan gum films: A strategy to improve the stability and prolong the cutaneous release of silibinin.

This study aimed to develop gellan gum films containing silibinin-loaded nanocapsules as a novel approach for cutaneous administration of this flavonoid. The nanocapsule suspensions were prepared and presented mean size around 140 nm with homogenous distribution, negative zeta potential and silibinin encapsulation efficiency close to 100%. Then, these suspensions were converted into gellan gum films by solvent casting method. The films were transparent, flexible and maintained the gellan gum hydrophilicity. Nanocapsules provided the silibinin homogenous distribution in the films and prolonged its release, as well as improved the gellan gum occlusion potential. Besides, the nanosuspensions conversion into films improved the silibinin stability. Additionally, the nano-based films presented a swelling index 1.5 times higher than films containing non-nanoencapsulated silibinin. Microscopic analysis evidenced the homogeneous surface of the nano-based films, while films containing non-nanoencapsulated silibinin presented small cracks. The in vitro skin permeation profile confirmed the silibinin gradual release from the nano-based films and its greater retention in the dermis when the skin is damaged. Finally, the formulations presented no irritant effect in the HET-CAM assay. Therefore, the conversion of silibinin-loaded nanocapsule suspensions into films might be considered a promising platform for skin delivery of this flavonoid.

Grinding the intaglio surface of yttria partially- and fully-stabilized zirconia polycrystals restorations: Effect on their fatigue behavior.

This study evaluated the effects of diamond bur grinding the intaglio surface of second (yttria partially-stabilized zirconia polycrystals, PSZ) and third-generation zirconia (fully-stabilized zirconia polycrystals, FSZ) adhesively cemented to dentin analogue substrate on the fatigue failure load, cycle number until failure, surface micromorphology and phase transformation. Disc-shaped specimens were produced from second (Katana ML-HT, Kuraray) and third-generation zirconia (Katana STML, Kuraray) and randomly allocated (n = 15) into two groups according to the intaglio surface treatment: Control - Ctrl (without grinding); Grinding - Gr (grinding at the center of the intaglio surface). The ceramic discs were adhesively cemented (Multilink Automix System) onto dentin analogue discs. Fatigue tests were executed by the step-stress method. The obtained data were analyzed by Kaplan Meier and Mantel-Cox tests. In addition, surface topography, roughness, phase transformation and fractography analyses were performed. SEM analysis showed that grinding increased the surface roughness and introduced defects in zirconia from both generations. Grinding increased the fatigue failure load, number of cycles to failure and survival rates of the second-generation zirconia statistically (control: 1373.33 N < grinding: 1600 N), while these same outcomes were reduced by grinding for the third-generation zirconia significantly (control: 766.67 N > grinding: 620 N). Thus, clinical adjustments with diamond burs damage the fatigue behavior of adhesively cemented third-generation zirconia.