Influence of cavity design on calcium hydroxide removal from root canal irregularities

Abstract

Objectives: Conservative endodontic cavity (CEC) design has recently developed to maintain the stability of tooth and provided an alternative to traditional endodontic cavity (TEC) design. The purpose of this study was to assess the influence of cavity design on calcium hydroxide (Ca(OH)2) removal from artificial grooves in the coronal and apical parts of root canals. Materials and Methods: Fourty extracted human mandibular premolars with single canals were randomly assigned to CEC or TEC groups (n=20). Following cavity preparation, the root canals were instrumented with ProTaper Universal rotary system up to F3 file and then, each tooth was sectioned longitudinally. Two standardized grooves were prepared in the coronal and apical parts of 1 root half. Ca(OH)2 was placed into the grooves and the root halves reassembled. After 1 week, each root canal was enlarged with a #40 H-file. Irrigation was performed with the sonic activation of 5 mL 2.5% sodium hypochlorite and 5 mL 17% ethylenediaminetetraacetic acid solutions using the medium size tip (25/04) of EndoActivator System at medium speed for 30 seconds between each 2.5 mL irrigant. The remaining Ca(OH)2 in the grooves was evaluated using a stereomicroscope with x25 magnification and the images were scored using a 4-scoring scale by 2 examiners. Data were analyzed using the Mann-Whitney U and Wilcoxon tests. Results: Ca(OH)2 remnants were found in both groups. There was no significant difference between the CEC and TEC groups in terms of Ca(OH)2 removal efficacy (p>0.05). The grooves in the coronal and apical parts of the roots presented similar amount of Ca(OH)2 remnants in both groups (p>0.05). Conclusions: Based on the present findings, the cavity design had no effect on the removal of Ca(OH)2 from root canal irregularities.