Impact of the acquired pellicle on the efficacy of at home whitening, the substrate and the whitening gel.

• Grant number: 25/05113-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2025
• End date: May 31, 2026
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: André Luiz Fraga Briso
• Grantee: Maria Eugênia Santos Almeida de Freitas
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

Prolonged use of at-home whitening gels can affect tooth structure. Modification of the acquired pellicle (AP) with a cystatin derived from sugar cane (CaneCPI-5) could optimize the aesthetic result and reduce adverse effects. The aim of this study was to evaluate the influence of PA modified or not by CaneCPI-5 on the efficacy and characteristics of the gel and substrate subjected to at-home bleaching with 10% carbamide peroxide. To this end, bovine enamel and dentin discs will be divided into the following groups: PS - placebo gel without PA; C10S - 10% carbamide peroxide bleaching gel without PA; PPA - placebo gel with PA; C10PA - 10% carbamide peroxide bleaching gel with PA; PPAC - placebo gel with PA modified with Cane CPI-5; C10PAC - 10% carbamide peroxide bleaching gel with PA modified with Cane CPI-5. To evaluate the whitening efficacy, 72 pigmented specimens (n=12) allocated to the groups will receive a total of 21 4-hour whitening sessions, and 5 spectrophotometer readings will be taken (baseline, after 7, 14, 21 days and 14 days after completion) to calculate the chromatic change (¿E00) and whitening index (¿WID). Analysis of the gel's characteristics will include diffusion tests (enzymatic method) and H¿O¿ degradation. Another 72 polished specimens will be divided into groups (n=12) to evaluate the substrate in roughness and surface microhardness tests before and after the treatments, and internal microhardness afterwards. The data will be submitted to specific statistical tests (¿=0.05).