Effect of Fast High-Irradiance Photo-Polymerization of Resin Composites on the Dentin Bond Strength

Scientific paper - Original scientific paper

• Author: Tobias Steffen
• Author: Matej Par
• Author: Thomas Attin
• Author: Tobias T. Tauböck
• Author's institution: University of Zagreb; School of Dental Medicine
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Dental Medicine; Endodonics and Restorative Dentistry

Abstract (english)

This study investigated the influence of conventional (10 s at 1160 mW/cm2) and fast high-irradiance (3 s at 2850 mW/cm2) light curing on the micro-tensile bond strength (μTBS) of bulk-fill resin composites bonded to human dentin. Sixty-four extracted human molars were ground to dentin and randomly assigned into eight groups (n = 8 per group). After application of a three-step adhesive system (Optibond FL), four different bulk-fill composites (two sculptable and two flowable composites) were placed. Of these, one sculptable (Tetric PowerFill) and one flowable (Tetric PowerFlow) composite were specifically developed for fast high-irradiance light curing. Each composite was polymerized with the conventional or the fast high-irradiance light-curing protocol. The specimens were cut into dentin-composite sticks, μTBS was determined and failure modes were analyzed. Statistical analysis was performed using t-test for independent observations and one-way ANOVA. A statistical difference between the curing protocols was only found for Tetric PowerFlow, where the conventional protocol (23.8 ± 4.2 MPa) led to significantly higher values than the fast high-irradiance light-curing protocol (18.7 ± 3.7 MPa). All other composite materials showed statistically similar values for both polymerization protocols. In conclusion, the use of fast high-irradiation light curing has no negative influence on the μTBS of the investigated high-viscosity bulk-fill composites. However, it may reduce the dentin bond strength of flowable bulk-fill composite.

• Keywords (english): high-irradiance light curing; rapid photo-polymerization; bulk-fill resin composites; micro-tensile bond strength; dentin adhesion; failure analysis
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Materials
• Numbering: vol. 15, no. 21, 7467
• e-ISSN: 1996-1944
• DOI: https://doi.org/10.3390/ma15217467
• URN:NBN: urn:nbn:hr:127:628455
• Publication: 2022-10-25
• Document URL: https://www.mdpi.com/1996-1944/15/21/7467
• Type of resource: Text
• Access conditions: Open access
• Created on: 2022-11-29 10:44:10