Effects of Different Over – the - Counter Whitening Products on the Microhardness, Surface Roughness, Color and Shear Bond Strength of Enamel

Abstract

Objective: The purpose of this in vitro study was to evaluate the effects of four over-the-counter (OTC) whitening products on the microhardness, surface roughness, color, shear bond strength (SBS) and surface charecteristics of human enamel compared with a product used for dentist-su-pervised home whitening. Material and methods: Seventy eight enamel specimens allocated into 6 groups (n=13): 1-Opalescence PF 10% (OP) dentist prescribed home whitening product, 2-Opalescence Go prefilled tray (PT), 3-Opalescence Whitening Toothpaste (WT), 4-Listerine Healthy White whitening mouth rinse (WMR), 5-Cavex Bite&White whitening pen (WP) and 6- no treatment (Con). The microhardness (VHN), surface roughness (Ra) and color of the specimens were measured (T 0 ). The specimens were then subjected to whitening protocols for 14 days (T 1 ). followed by artificial saliva storage for 14 days (T 2 ). The measurements were repeated at T 1 and T 2 . The SBS test was done after the application of 35% phosphoric acid (Scotchbond Universal Etchant), followed by a universal adhesive (G-Premio Bond) and a micro hybrid/universal resin composite (Essentia) into a Teflon tube attached to the enamel surface (p0.05). Ra values of enamel specimens increased with the application of OP, PT and WT (p0.05). OP, PT, WMR, and WP changed the color of the enamel(p<0.05). There were not any significant differences among the SBSs of the groups, apart from OP applied enamel specimens. OP showed the least SBS values (p=0.001). SEM observations revealed smooth enamel surfaces. Conclusions: The whitening products affected the microhardness, surface roughness, color of enamel differently. Only OP decreased the SBS of the enamel.

Keywords

• Tooth Bleaching
• Tooth Bleaching Agents
• Dental Enamel
• Hardness Tests
• Surface Properties
• Color