Evaluation of the physicochemical properties of a self-etch adhesive system incorporated with nanochitosan particles

Author(s)

Pâmella Coelho Dias

• Document type: Doctoral Thesis
• Press: Ribeirão Preto.
• Institution: Universidade de São Paulo (USP). Faculdade de Odontologia de Ribeirão Preto (PCARP/BC)
• Defense date: 2023-10-24

Examining board members

Regina Guenka Palma Dibb; Ricardo Marins de Carvalho; Cesar Penazzo Lepri; Francisco Wanderley Garcia de Paula e Silva

• Advisor: Regina Guenka Palma Dibb

Abstract

This study aimed to develop, characterize, and evaluate in vitro the physicochemical properties of a two-step self-etch adhesive system incorporated with nanochitosan gel at different concentrations in the primer and bond (5%, 10%, and 15%). Specific objective 1: to evaluate experimental primers regarding the morphological characterization of coronal and root dentin surface of bovine incisor teeth and their influence on the adhesive interface. Specific objective 2: to evaluate the influence of experimental primers on wettability, proteolytic inactivation, and antibacterial activity in dentin. Specific objective 3: to characterize and evaluate the effects of the experimental bonds on sorption, water solubility, degree of conversion, flexural strength, and potential bioactivity. Specific objective 4: to evaluate the physical properties and quality of the hybrid layer of an experimental and a commercial two-step self-etch adhesive system incorporated with 5% nanochitosan gel through microtensile testing, wettability, and interface analysis by scanning electron microscopy. In general, it was observed that a concentration of 15% of nanochitosan in the experimental primer affected the quality of the adhesive interface; the incorporation of nanochitosan in the experimental primer does not interfere with wettability, inactivation of metalloproteinases, and antimicrobial action; the concentration of 15% nanochitosan in the experimental bond negatively interferes with the degree of conversion of the experimental bond, 10% nanochitosan affects the flexural strength and modulus of elasticity, and 5% nanochitosan incorporated into the experimental bond presents bioactive properties without affecting the physical properties of the bond material. The incorporation of 5% nanochitosan in the primer and bond of the commercial adhesive showed an improvement in the quality of the adhesive interface without interfering with adhesive strength and wettability, indicating its potential for clinical application. (AU)

• FAPESP's process: 19/20997-6 - Evaluation of the physicochemical properties of a self-etch adhesive incorporated with nanochitosan particles
• Grantee: Pâmella Coelho Dias
• Support Opportunities: Scholarships in Brazil - Doctorate