Bacterial Colonization and Proliferation in Furcal Perforations Repaired by Different Materials: A Confocal Laser Scanning Microscopy Study

Abstract

Following furcal perforation, bacteria may colonize the defect and cause inflammation and periodontal destruction. This study used confocal laser scanning microscopy (CLSM) to evaluate Enterococcus faecalis colonization and proliferation in furcal perforations repaired with different materials. Furcal perforations created in 55 extracted human mandibular molars were repaired using either MTA-Angelus, Endocem, or Biodentine and coronally subjected to E. faecalis suspension for 21 days. The specimens were then stained using a LIVE/DEAD Viability Kit and visualized by CLSM. The minimum and maximum depths of bacterial penetration into the dentinal tubules were 159 and 1790 μM, respectively, with a mean of 713 μM. There were significantly more live than dead bacteria inside the dentinal tubules (p = 0.0023) in all groups, and all three repair materials exhibited a similarly sized stained area (p = 0.083). However, there were significant differences in the numbers of dead bacteria at the circumference of the perforation defect (p = 0.0041), with a significantly higher ratio of live to dead bacteria in the MTA-Angelus group (p = 0.001). Following perforation repair, bacteria may colonize the interface between the repair material and dentin and may penetrate through the dentinal tubules. The type of repair material has a significant effect on the viability of the colonizing bacteria.

Comparative Analysis of Bacterial Colonization in Simulated Vertical Root Fractures of Root Canals Filled with Various Obturation Materials using Confocal Laser Scanning Microscopy

“…CLSM is a valuable modality of choice alongside more traditional SEM and PCR-based techniques to identify viable bacteria in dentinal tubules [10,[12][13][14][15]. Importantly, using CLSM with the live/dead staining method allows us to assess the extent of contamination and vitality of bacteria in the dentinal tubules [10,[12][13][14][15]. No study has used CLSM to evaluate the bacterial colonization in VRF of extracted human teeth lled with different materials.…”

“…Understanding the sealing ability of materials used during root canal treatment in teeth with VRF and predicting the amount and direction in the presence of bacterial leakage is paramount in revealing the pathologies related to VRF [27,28]. CLSM is a valuable modality of choice alongside more traditional SEM and PCR-based techniques to identify viable bacteria in dentinal tubules [10,[12][13][14][15]. Importantly, using CLSM with the live/dead staining method allows us to assess the extent of contamination and vitality of bacteria in the dentinal tubules [10,[12][13][14][15].…”

“…Confocal laser scanning microscopy (CLSM) has been used in previous studies to examine the nature of bacterial colonization in VRFs [10,[12][13][14][15]. However, there is still a need to investigate the relationship between the type of intracanal lling material and the bacterial colonization of VRF.…”