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Published on: July 4, 2018
Bacterial colonization in the apical part of extracted human teeth following root-end resection and filling: a
Igor Tsesis1, Shlomo Elbahary1, Nuphar Blau Venezia1
1Department of Endodontology, Maurice and Gabriela Goldschleger School of Dental Medicine, Tel Aviv University, P.O. Box 39040, 6997801, Tel Aviv, Israel.
Objectives:
The purpose of this study was to evaluate Enterococcus faecalis colonization at the apical part of root canals following root-end resection and filling using confocal laser scanning microscopy (CLSM).
Materials And Methods:
The apical 3-mm root-ends of 55 extracted single rooted human teeth were resected, and 3-mm retrograde cavities were prepared and filled using either mineral trioxide aggregate (MTA), intermediate restorative material (IRM), or Biodentine (n = 10 each); 25 teeth served as controls. The roots were placed in an experimental model, sterilized, and coronally filled with E. faecalis bacterial suspension for 21 days. Then, the apical 3-mm segments were cut to get two slabs (coronal and apical). The slabs were stained using LIVE/DEAD BacLight Bacterial Viability Kit and evaluated using CLSM.
Results:
The fluorescence-stained areas were larger in the bucco-lingual directions compared with the mesio-distal directions (p < 0.05). The mean and maximal depths of bacterial colonization into the dentinal tubules were 755 and 1643 μm, respectively, with no differences between the root-end filling materials (p > 0.05). However, more live bacteria were found in the MTA group in comparison to IRM and Biodentine groups (p < 0.05).
Conclusions:
CLSM can be used to histologically demonstrate bacterial root-end colonization following root-end filling. This colonization at the filling-dentine interfaces and deeper into the dentinal tubules may be inhomogeneous, favoring the bucco-lingual aspects of the root.
Clinical Relevance:
Following root-end resection and filling bacterial colonization may lead to inflammatory reactions at the periapical tissues; the viability of the colonized bacteria may be affected by the type of root-end filling material.
