INFLUENCE OF SURFACE RESIN COATING ON THE SUSCEPTIBILITY OF ACTUAL RESIN COMPOSITES TO BLEACHING

• Published in: International journal of medical dentistry 2022-01, Vol.26 (1), p.30-37
• Main Authors: Abdelaziz, Khalid M, Alshahrani, Noura H, Alshahrani, Ghada H, Alqahtani, Monerah M, Alqahtani, Nwaf M
• Format: Article
• Language: English
• Subjects: Aging; Bleaching; Composite materials; Polymerization; Statistical analysis
• ISSN: 2066-6063; 2392-8018

Most of them utilized a considerable amount of nano-sized inorganic fillers that helps improve the optical and filler loading characteristics of the resulted resin composite restoratives. [...]the presence of high loads of nano-fillers showed direct reflections on composites' rate of polymerization shrinkage, as well as on their resistance to wear [3]. [...]the null hypothesis was that coating resin composite surfaces with a protective resin layer would not influence susceptibility to bleaching. 2.MATERIALS AND METHODS Four groups (n=60 each) of disc-like specimens, 7 mm in diameter and 4 mm thick, were constructed out of Filtek Z350 (3M ESPE, St. Paul, MN) (FZ, G1), Ceram X (Dentsply-Sirona, Charlotte, NC) (CX, G2), Tetric N Ceram (IvoclarVivadent, Shane, Lichtenstein) (TNC, G3), and Tetric N Ceram- bulk Fill (Ivoclar- Vivadent, Shane, Lichtenstein) (TNB, G4) resin composites. Construction of resin composite specimens Specimens of groups 1-3 were constructed in two, 2 mm thick increments, each one adapted into the mold cavity and light cured for 20s using LED curing light at an intensity of 1200 mW/cm2 and wavelength of 430-480 nm (Elipar S10, 3M ESPE AG, Seefeld, Germany). Statistical analysis of the recorded results The calculated differences in the recorded color parameters (AL·, Aa· and Ab·), as well as the amounts of color change (AE) following the bleaching procedure were statistically analyzed using 2-Way ANOVA test and Tukey's pairwise comparisons at a= 0.05, to evidence any differences detected among the investigated subgroups. 3.RESULTS Table 2 lists the means and standard deviations of the calculated change in the colors of the tested resin composites (AE), in addition to the differences in color parameters (AL·, Aa· and Ab·) measured both before and after bleaching of specimens in all test subgroups.