Microleakage and Micromorphology of the Resin-dentin Interface in Primary Molars Following Different Endodontic Irrigation Regimens

The aim of this study was to evaluate the effect of two endodontic irrigants (2.5% sodium hypochlorite and 17% Ethylenediamintetraacetic acid) on the microleakage and micromorphology of the resin-dentin interface in pulpectomized primary molars. Standardized Class-II cavities were prepared in extracted, non-carious primary molars after which chemo-mechanical preparation of the root canals were performed in conjunction with K-Files and 2.5% sodium hypochlorite (NaOCl) between each file size. Final irrigation of the specimens were made with either 2.5 NaOCl, 17% Ethylenediamintetraacetic acid (EDTA) or with saline (control). The root canals were filled with a calcium hydroxide paste and the cavities were sub-grouped to be restored with one of the following materials: a: Amalgam, b: Prime&Bond NT (with prior total etch) and TPH resin-based composite, c: Prime&Bond NT and Dyract d: Prime&Bond NT (with Non-Rinse Conditioner pre-treatment); and e:Prompt L-Pop and F2000. Following thermocycling and 90-day water storage, the occlusal and gingival microleakage of restorations were assessed with dye penetration and image analysis. Separate specimens were processed for scanning electron microscopic investigation of the resin-dentin interface. The occlusal and gingival microleakage of the tested restorative systems was not affected by different irrigation regimens (p>0.05), while final restoration with Prime&Bond NT+TPH and Prompt L-Pop+F2000 resulted in the lowest microleakage values (p<0.05). Following the use of 17% EDTA for final flush, the latter two groups produced relatively thicker hybrid zones, when compared to the saline-irrigated specimens.

Tooth, primary; Irrigation; Sodium Hypochlorite; EDTA; Microleakage; Hybrid zone; Image analysis

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