Push-Out Bond Strength of Different Luting Cements Following Post Space Irrigation with 2% Chitosan: An In-Vitro Study

Background. The optimum bond strength of glass fiber posts can be compromised, and it is not yet clear which final irrigant in combination with the luting cement used can improve its bond strength. Objectives. This study was designed to study the effect of 2% Chitosan
as a final irrigant in combination
with different types of luting cement
used to improve the bond strength of glass fiber posts bonded to root canal
treated teeth. Methods. 30 single-rooted anterior teeth were collected and sectioned 2 mm above the cementoenamel junction’s most incisal point.
After root canal filling, post spaces were prepared and irrigated as follows: Group I: Using 17% EDTA for 3 minutes, and Group II: Using 2% Chitosan for 3 minutes. Each group was subdivided
into 3 subgroups: Fiber posts were cemented with subgroup A: Fuji II Cement
(Resin reinforced glass ionomer cement), subgroup B: Rely X Unicem (Self-adhesive
resin cement), and subgroup C: Metacem Refill (Total-etch resin cement). Push-out bond
strength (N) for each sample was measured using a universal testing machine,
failure mode was assessed with stereomicroscope 30X magnification, while the
morphological structure of the fiber posts was analyzed using Scanning Electron
Microscopy. Statistical analysis including one-way ANOVA followed by Tukey's
post hoc test in case of significant differences between the groups. P-values
less than 0.05 were considered statistically significant. Results. The study found that there is no statistically significant
difference between using 17% EDTA or 2% Chitosan as the final irrigant before post
placement (p>0.05). While RelyX Unicem cement showed
significant bonding strength when used with 2% chitosan the coronal, middle,
and apical thirds. (p-0.009, p-0.02, p-0.01 respectively). Conclusions. 2% Chitosan can be considered a good alternative for 17% EDTA when used as a final irrigant for the post space.