In vitro assessment of the influence of endodontic chemical irrigants on the bond strengths and durability of adhesion to root canal walls

Author(s)

Shaiana Tashy Kawagoe

• Document type: Master's Dissertation
• Press: Piracicaba, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Odontologia de Piracicaba
• Defense date: 2010-09-20

Examining board members

Caio Cezar Randi Ferraz; Alyne Simões; Francisco José de Souza Filho

• Advisor: Caio Cezar Randi Ferraz

Abstract

The prognosis of the endodontic treatment is improved by a correct sealing of the coronal access soon after the root canal obturation, preventing the root canal system recontamination and minimizing the risk of fracture. Due to their excellent mechanical properties and sealing ability, the adhesive systems are considered choice material for teeth restoration. However, the adverse effects related to the type of auxiliary chemical substances used during the endodontic treatment, as well as its influence on the adhesive strength and longevity need greater clarification. The objective of the present study was to examine the adhesive strength and longevity 2 adhesive systems (Scotchbond Multi Purpose and Clearfil SE Bond), applied in radicular dentin treated with different auxiliary chemical substances (2% chlorhexidine gel, EDTA 17% and 5.25% sodium hypochlorite (NaOCl) associated or not to sodium ascorbate 10%), and evaluate the importance of the collagen fibers in adhesion process. The shear bond strength was assessed after 1 day or 1 year in water immersion. As longevity control, part of the sample was kept submerged in mineral oil for 1 year. Subsequently, the fracture pattern was analyzed using a stereomicroscope (25 X), and classified as: adhesive (dentin/resin interface), cohesive (in dentin, layer hybrid resin or post) or mixed (involving 2 or more substrates). After the data analysis it was concluded that: the Scotchbond Multi Purpose presented the best results. The NaOCl reduced the immediate adhesive resistance when used as an endodontic auxiliary chemical substance or when employed in deproteinization. The use of sodium ascorbate after using the NaOCl re-established the adhesion values. The deproteinization and chlorhexidine use kept the adhesive strength values unchanged after 1 year. (AU)