Statement of the Problem: The most common cause of endodontic treatment failures is improper coronal sealing. Therefore, besides to proper root sealing, coronal sealing which is supported by a proper restoration has a major role in endodontic treatment success, and coronal microleakage should be considered as an etiologic factor in endodontic treatment failure. Infact this leakage shows its affect by penetration through the coronal part of root canal, therefore the aim of this study was to evaluate the effect of glass-ionomer (GI) thickness as a coronal barrier on microleakage after endodontic treatment.
Purpose: This study aimed to evaluate the coronal microleakage in GI-obturated root canals in endodontically treated teeth using different thicknesses of GI.
Materials and Method: Forty-five single-rooted extracted human teeth with single canals were collected and disinfected with 0.5% chloramine solution. Endodontic treatment was undertaken and the teeth were divided into 3 groups: group 1: 1 mm of gutta-percha, group 2: 2 mm of gutta-percha and group 3: 3 mm of gutta-percha was removed and GI respectively was replaced at 1-, 2- and 3-mm thicknesses. Then subgroups were placed in methylene blue dye and the microleakage was assessed using dye penetration.
Results: The mean dye penetration in groups 1, 2 and 3 were 5.1, 3.7 and 2.9, respectively, with statistically significant differences. Group 1 exhibited the highest amount of dye penetration while group 3 showed the least one. Also comparisons between groups showed a significant difference between groups 1 and 2 in mean dye penetration (p= 0.002) but this was not significant between groups 2 and 3 (p= 0.098).
Conclusion: The results of the present study indicated that a thicker GI layer might be associated with a decrease in coronal microleakage. Although the results showed that GI at 3-mm thickness resulted in the best protective effect on coronal microleakage in endodontically treated teeth, further studies are needed to confirm these results.