Comparison of bacterial and dye leakage among seven materials

Objectives:

The aim of this study was to investigate, in vitro, bacterial and dye leakage among 7 root-end filling materials and compare the efficacy of these two methods.

Methods:

90 single-rooted teeth were decoronated and their roots instrumented to size 40 within 1 mm of apex using step-back technique. Each tooth was apicaly resected and a cavity having 3 mm depth was prepared at the apex. Seven groups of 12 roots were retrofilled with the following materials; IRM, White MTA, Amalgam, Portland cement type II, Gray MTA and Glass Ionomer. Six roots were used as negative and positive control groups.

The roots were then exposed at their coronal end first for 70 days to TSB (containing Enterococcus Faecalis) which followed by exposing to methylene blue 1% for 72h.

Bacterial leakage was recorded when the challenging organism could be recovered from the apical end. Complete dye leakage was checked by microscopy of transverse section of the apical tip and finally the roots were sectioned and the depth of dye penetration was evaluated by stereomicroscope at X 12 magnification.

Results:

In bacterial leakage, after 70 days there was significant difference only between Gray MTA (58.3% leakage) and Amalgam, Portland cement, GI (100% leakage for 3 groups).

In dye leakage there was significant difference only between Gray MTA (0.42 mm penetration) and IRM (1.85 mm penetration) and Amalgam (1.98 mm penetration).

Conclusion:

There was no significant measure of agreement between dye and bacterial penetration along root end fillings.