Effect of dentin cleaning to remove endodontic cement residues and adhesive technique on the bond strength durability of dental restorations

• Grant number: 24/22138-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2025
• End date: February 28, 2026
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Anderson Catelan
• Grantee: Natália Barros Ferracin
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

Aim: To evaluate the effect of dentin cleaning agents for removal of endodontic cement residues and the adhesive technique of a universal adhesive on the bond strength durability of resin composite restorations. Material and method: The coronal dentin of the vestibular surface of one hundred and forty bovine incisors will be planned, then the teeth will be divided (n = 10) according to the cleaning agent (acetone, alcohol, amyl acetate, xylol, orange oil (Citrus sinensis), eucalyptol, and distilled water) and the adhesive technique (self-etching and reduced time of acid etching). Cleaning will be performed by scrubbing the solutions for 10 s, prophylaxis with pumice stone and water for 15 s, followed by the adhesive protocol. In the self-etching mode, the universal adhesive will be actively applied for 20 s, volatilized for 5 s and light cured for 10 s. For the dentin etching groups, 35% phosphoric acid will be applied for 3 s, followed by rinsing, drying while maintaining dentin moisture, and application of the universal adhesive as previously described. Then, a rectangular block (3.5 x 4.8 mm and 4 mm thick) of composite will be fabricated in two 2 mm thick increments. Light curing of the materials will be performed for the time recommended by the manufacturers with a polywave LED with irradiance of 1000 mW/cm2. Specimens will be cut into 1 x 1 mm sticks (~6) and evaluated after 24 h. Half of the sticks (~3) will be evaluated after 24 h and the other half after 20,000 thermal cycles (5 and 55°C, 30 s). Bond strength by microtensile testing will be obtained using a semi-universal testing machine. The fracture pattern will be evaluated under a stereomicroscope. Method of analysis of results: Data obtained will be tabulated, analyzed, and subjected to the most appropriate statistical tests, adopting a significance level of 5%. Expected results: It is expected that dentin cleaning agents will not affect and acid etching will increase and maintain stable adhesion.