Influence of solvents on the bond strength of resin sealer to intraradicular dentin after retreatment

Abstract

Influence of solvents on the bond strength of resin sealer to intraradicular dentin after retreatment Abstract: This study evaluated the removal of filling material with ProTaper Universal Rotary Retreatment system (PTR) combined with solvents and the influence of solvents on the bond strength (PBS) of sealer to intraradicular dentin after canal reobturation. Roots were endodontically treated and distributed to five groups (n = 12). The control group was not retreated. In the four experimental groups, canals were retreated with PTR alone or in combination with xylol, orange oil, and eucalyptol. After filling material removal, two specimens of each group were analysed by SEM and µCT to verify the presence of filling remnants on root canal walls. The other roots were reobturated and sectioned in 1-mm-thick dentin slices that were subjected to the push-out test. Data were analysed by two-way ANOVA and Tukey's test (α = 0.05). SEM and µCT analysis revealed that all retreatment techniques left filling remnants on canal walls. The control group (3.47 ± 1.21) presented significantly higher (p < 0.05) PBS than the experimental groups. The groups retreated with PTR alone (2.59 ± 0.99) or combined with xylol (2.54 ± 0.77) and orange oil (2.32 ± 0.93) presented similar bond strength (p > 0.05), and differed significantly from the group with eucalyptol (1.89 ± 0.63). The solvents reduced the PBS of the sealer to dentin and no retreatment technique promoted complete removal of filling material.

Efficacy and Cytotoxicity of Binary Mixtures as Root Canal Filling Solvents

“…Damage to the root dentine walls, which is observed with highly potent solvents, such as chloroform or xylene, is not expected due to the lower aggressive profile of the solvents included in these mixtures [26][27][28].…”

Citric Acid: An Alternative for the Removal of Root Canal Filling Materials&nbsp;

“…While chemical revision may lead to undesired demineralization effects that might weak the root canal structure, there are no standard protocols related with time, amount and concentration of solvents used, not even their consequences or impact over dentine microhardness due to the possibility of mineral loss; although this is still a matter of debate. Some reports claimed that the use of solvents improved the cleaning e cacy from root canal areas di cult to access with intracanal instruments [35]. However, there is no solvent that is able to provide a complete removal of lling material and it could be thought that it might have an adverse effect on the bond strength of resin sealer into intra-radicular dentin, in terms of root canal lling or even in ber posts adhesion [36].…”

Evaluation of the efficacy of filling material removal and re-filling after different retreatment procedures

“…7,31 This effect compromises the cleaning of the root walls and delays the removal stage. In addition, other studies 32,33 have demonstrated that the use of a solvent decreases the bond strength of endodontic sealers, a consequence which may compromise successful retreatment. Some studies 31,34 recommend avoiding the use of solvents, and using only auxiliary chemical substances during removal of filling material.…”