Effect of whitening toothpastes on the physical properties of a composite resin during bleaching with 10% carbamide peroxide

• Grant number: 20/13572-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2021
• End date: December 31, 2022
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Laura Nobre Ferraz Jardim
• Grantee: Carolina Meneghin Barbosa
• Host Institution: Pró-Reitoria de Gradução. Centro Universitário Hermínio Ometto (UNIARARAS). Fundação Hermínio Ometto (FHO). Araras , SP, Brazil

Abstract

The aim of this in vitro study will be to investigate the effects of different whitening toothpaste used during bleaching with 10% carbamide peroxide in a micro-hybrid composite resin. A total of 48 cylindrical samples will be prepared with a micro-hybrid composite resin and will be randomized into 4 groups according to the toothpaste to be used: Colgate Total 12 Clean Mint, Colgate Luminous White Brilliant, Luminous White Instant, Colgate Luminous White Expert. The bleaching of the samples will be carried out with 10% carbamide peroxide for 4 hours for 14 days. Twice a day, before and after dental bleaching, the samples will be brushed. For this, the specimens will be immersed in the "toothpaste slurry" (ratio of 1g toothpaste to 3ml of distilled water). The specimens will be brushed for 15 s (load 200 g) and will be kept in the toothpaste slurry until a total of 2 minutes. Color analyzes will be performed using reflectance spectroscopy (L, a, b, E * ab, E00). In addition, surface microhardness analyzes will be carried out (SMH) and surface roughness analysis (Ra) will be performed at baseline times (T0) and after 14 days of tooth bleaching and toothbrushing (T1). The data will be submitted to appropriate statistical analysis considering a significance level of 5%.