Abstract
The aim of this study was to evaluate the bond strengths of composite restorations made with different filler amounts and resin composites that were photoactivated using a light-emitting diode (LED). Thirty bovine incisors were selected, and a conical cavity was prepared in the facial surface of each tooth. All preparations were etched with Scotchbond Etching Gel, the Adper Scotchbond Multipurpose Plus adhesive system was applied followed by photoactivation, and the cavities were filled with a single increment of Filtek Z350 XT, Filtek Z350 XT Flow, or bulk-fill X-tra fil resin composite (n = 10) followed by photoactivation. A push-out test to determine bond strength was conducted using a universal testing machine. Data (MPa) were submitted to Student's t-test at a 5% significance level. After the test, the fractured specimens were examined using an optical microscope under magnification (10x). Although all three composites demonstrated a high prevalence of adhesive failures, the bond strength values of the different resin composites photoactivated by LED showed that the X-tra fil resin composite had a lower bond strength than the Filtek Z350 XT and Filtek Z350 XT Flow resin composites.
Highlights
The contraction of dental composites is reported to be approximately 1–5% of their volume [1, 2]
The purpose of this study was to evaluate the bond strengths of composite restorations photoactivated using a light-emitting diode (LED) that were made with different filler amounts and resin composites
The null hypothesis tested was that there is no difference in bond strength among the composite restorations photoactivated using LED that were made with different filler amounts and resin composites
Summary
The contraction of dental composites is reported to be approximately 1–5% of their volume [1, 2] The insertion of these contracting materials into bonded preparations induces the development of mechanical stress inside the material [2]. In light-cured composites, a rapid conversion induces a correspondingly rapid increase in composite stiffness, causing high shrinkage stresses at the restoration-tooth interface. Such stresses may disrupt the bonding between the composite and the cavity walls or may even cause cohesive failure of the restorative material or the adjacent tooth tissue [2]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
