Efficacy of different instruments for the mechanical removal of the smear layer in immediate post preparations: a comparative study.

Adhesively cemented fiber-reinforced composite posts are commonly used to reconstruct endodontically treated teeth. Adhesion to intraradicular dentin is complex, and close contact between the resin cements and the dentin is essential. The removal of the smear layer following post space preparation (secondary smear layer) can improve this integration.

Post preparation: cleanness achieved by different irrigating protocols.

The aim of this study was to evaluate the ability of different irrigation protocols to remove from the walls of the root canal and entrance to dentinal tubules the smear layer produced during preparation for a fiber post. Fifty decoronated human lower premolars were treated endodontically and the apical third of the canal was filled with a single gutta-percha point using warm vertical compaction. Ten millimeters were left free for post preparation, which was done by sequential use of a Largo #1 drill and Exacto #3 pilot drill (Angelus, Brazil), with irrigation with distilled water upon each instrument change.

Evaluation of the incidence of transportation after placement and removal of calcium hydroxide.

The purpose of this in vitro study was to evaluate the incidence of apical transportation after the placement and removal of Ca(OH)2 in straight and curved root canals. Twenty maxillary central incisors (group A) and 20 mesiobuccal canals from mandibular molars (group B) were instrumented at the working length to a #45 file and #30 file, respectively. Postinstrumentation radiographs were taken with the corresponding final file inserted into the canal to the working length.

Reinforcing effect of a resin glass ionomer in the restoration of immature roots in vitro.

Fifty-six extracted maxillary central incisors were used for this study. The crown of each tooth was removed in order to obtain a standard length of 13 mm. Root canals were enlarged to simulate immature teeth after apexification.