Author : Sherif Khadr,Essam Abdelhafez
Source : FDI 2018 - World Dental Congress, At Buenos Aires, Argentina
Date of Publication : 09/2018
Abstract :
Aim or purpose: This study was carried out to investigate the microshear bond strength (µSBS) of multi-mode adhesive (MMA) to different regions and prism orientations of enamel. Materials and Methods: Enamel substrates (n=80) were categorized into two main groups (n=40) according to the enamel regions tested; either cuspal or midcoronal enamel. Each region was then prepared either in axial or tangential sections (n=20). Then enamel specimens were bonded with MMA either in self-etch (SE) or etch-and-rinse (ER) adhesion protocol (n=10). Nano-filled flowable composite was used to prepare µSBS specimens. µSBS was assessed using universal testing machine. Resin-enamel interface was assessed under environmental scanning electron microscope. Statistical analysis was carried out using three way ANOVA test. Results: Results of the µSBS testing revealed no statistically significant difference between mean µSBS value of enamel regions tested, while bonding using MMA to tangentially sectioned enamel recorded a statistically significant (p≤0.001) higher mean µSBS value than bonding to axially sectioned enamel, also ER adhesion protocol recorded a statistically significant higher (p≤0.001) mean µSBS value compared to bonding using the SE adhesion protocol. In all specimens the hybrid layer was clearly detected with intimate adaptation between the adhesive resin and enamel, ER specimens showed clear resin microtags, while SE specimens did not show resin microtags except in the case of the axially sectioned cuspal enamel. Conclusions: The bond strengths of the MMA is influenced by the direction of enamel rods. Application of MMA in ER adhesion protocol improves the resin-enamel bond strength. Powered by TCPDF (www.tcpdf.org)
Download PDF