Evaluation of the interface between gutta-percha and two types of sealers using scanning electron microscopy (SEM)

The aim of the present study was to evaluate the adaptation of a calcium silicate bioceramic (BC) sealer with either BC or conventional gutta-percha compared with that of AH Plus sealer in different root canal sections.

Seventy-two extracted mandibular premolars were divided randomly into six groups. After standardised chemomechanical preparation, four groups were obturated with the BC sealer and BC gutta-percha or conventional gutta-percha, and the other two groups were obturated with AH Plus sealer and conventional gutta-percha either in lateral compaction or in a single cone technique. Each root was sectioned into three sections. An impression was made from each section, and replicas were then made for scanning electron microscopy (SEM) analysis. Areas and interfacial gaps were identified using image analysis software. In addition to descriptive and explorative data analyses, linear regression analysis was performed.

All specimens had measurable interfacial gaps. Significantly fewer gaps were found between conventional gutta-percha and sealer compared to those observed when using the BC gutta-percha (p < 0.001). However, minor interfacial gaps between sealer and dentin were observed with the BC sealer (p = 0.04). The technique of obturation in different root canal sections did not significantly affect the sealer adaptability.

The type of gutta-percha as well as the sealer had a noticeable impact on the adaptability.

Different obturation techniques will result in similar outcomes. However, within the limitations of the study, there seems to be no advantage in using the BC gutta-percha.