Shear bond strength of eugenol- and non-eugenol–based endodontic sealers to gutta-percha and dentin: An in vitro study

AIMS: a) To evaluate the bond strength of eugenol- and non-eugenol-based endodontic sealers to gutta-percha and dentin and b) To make a comparative evaluation of the bond strength of sealers to gutta-percha and dentin. MATERIAL AND METHODS: Seventy-two specimens were used in this study, which was divided into two groups — group I consisting of 36 freshly extracted human molars with 2 mm coronal cut surface; and group II consisting of gutta-percha disks of 10 mm diameter and 2 mm thickness embedded in 36 plaster of Paris specimens. Group I was further divided into three subgroups: subgroup 1, subgroup 2, and subgroup 3, consisting of 12 teeth each; and group II was further divided into three subgroups: subgroup 1, subgroup 2, and subgroup 3, consisting of 12 plaster specimens each. Each subgroup consisted of two materials each, which were placed in 5 mm long sections of polyethylene tubing and were then placed on coronal 2 mm cut surface of human molars; likewise subgroup 1, subgroup 2, and subgroup 3 of group II consisted of two materials each, which were also placed in 5 mm long sections of polyethylene tubing and then placed on gutta-percha disks 10 mm in diameter and 2 mm in thickness, which were embedded in the plaster specimens. After the materials were set, the specimens were subjected to test for shearing bond strength using a universal testing machine (Instron). STATISTICAL ANALYSIS: Mann-Whitney U test. RESULTS: Group I, i.e., zinc oxide eugenol sealers, showed more bond to gutta-percha than to dentin, in which subgroup 2b, endomethasone, showed the maximum bond. Group II, i.e., non-zinc oxide eugenol sealers, showed more bond to dentin than to gutta-percha, where the maximum bond was shown by subgroup 3b, EndoRez. CONCLUSION: Under the circumstances of this in vitro study, all the six endodontic sealers had significant differences in terms of shear bond strength to gutta-percha and dentin.