Effect of Hydrogel-Based Antibiotic Intracanal Medicaments on Push-Out Bond Strength

This study aimed to evaluate the effects of typical clinical concentration (1,000 mg/mL), low concentration (1 mg/mL) triple antibiotic pastes (TAP), and double antibiotic pastes (DAP) on the bond strength between various root cements and radicular dentin.

Intact single-rooted human teeth (n = 144) were horizontally decoronated and canals instrumented. The roots were treated for 4 weeks with Ca(OH)₂, 1,000 mg/mL of TAP or DAP, and 1 mg/mL of TAP or DAP. Untreated roots served as a control. After treatment, the medicaments were irrigated and each group was divided into three subgroups receiving MTA, Biodentine, or Endosequence putty cement. After 2 weeks, coronal and middle root cylinders were obtained from each root. Push-out bond strength test and failure analysis were performed for all root cylinders.

Three-way ANOVA, pairwise comparisons and logistic regression were used for statistical analyses. A significance level of 5% was used.

For MTA applied in the coronal part of the roots, 1 mg/mL DAP and TAP and Ca(OH)₂ demonstrated significantly higher bond strength compared with the typical clinical concentration and the control groups. For Biodentine applied coronally in the roots, 1 mg/mL of DAP resulted in significantly higher bond strength than all other groups. For Endosequence putty cement applied coronally in the roots, 1 mg/mL of DAP offered significantly higher bond strength than all groups except for Ca(OH)₂.

The use of 1 mg/mL DAP resulted in significantly higher push-out bond strength compared with the typical clinical concentration of TAP and DAP regardless of the type of the root cement used.