Correlation Between Volume of Root Canal, Cultivable Bacteria, Bacterial Complexes and Endotoxins in Primary Infection.

Flávia Goulart Da Rosa Cardoso,Marco Antônio Rocco,Marcia Carneiro Valera,Renata Falchete Do Prado,Luiz Roberto Coutinho Manhães-Júnior,Nádia De Souza Ferreira,Frederico Canato Martinho

doi:10.1590/0103-6440201902239

Abstract

This clinical study was conducted to correlate the levels of endotoxins and culturable bacteria found in primary endodontic infection (PEI) with the volume of root canal determined by using Cone Beam Computed Tomography (CBCT); and to evaluate the bacterial diversity correlating with clinical features. Twenty patients with PEI were selected and clinical features were recorded. The volume (mm3) of root canal was determined by CBCT analysis. Root canal samples were analyzed by using kinetic LAL-assay test to determine the levels of endotoxins and anaerobic technique to determine the bacterial count (CFU/mL). DNA was extracted from all samples to determine bacterial diversity and quantified by using Checkerboard-DNA-DNA- Hybridization. Culturable bacteria and endotoxins were detected in 100% of the root canal samples. Linear regression analysis revealed a correlation between root canal volume and presence of anaerobic bacteria (p<0.05). Positive correlations were found between bacteria species and presence of different clinical features (p<0.05). After grouping the bacteria species into bacterial complexes, positive associations were found between green, orange and red complexes with presence of sinus tract (p<0.05). This clinical study revealed that larger root canals hold higher levels of culturable bacteria in PEI. Thus, the interaction of different virulent bacteria species in complexes seems to play an important role in the development of clinical features.

Highlights

Knowledge of the pathogenesis of endodontic infections is important for establishing therapeutic strategies [1]
Braz Dent J 30(2) 2019 of endotoxins and culturable bacteria found in primary endodontic infection (PEI) with the volume of root canal determined by using cone beam computed tomography (CBCT), as well as to evaluate the bacterial diversity correlating with clinical features
Bacteria and endotoxins were detected in 100% of the root canal samples (20/20) with median values of 8.4 x 105 CFU/mL (7.4 x 105–28.8 x 105 CFU/mL) and 17.45 endotoxin units (EU)/mL (21.2 – 103 EU/mL), respectively

Summary

Introduction

Knowledge of the pathogenesis of endodontic infections is important for establishing therapeutic strategies [1]. Special attempt has been given for the knowledge bacterial species and their association in complexes [2,3,4,5]. Interactions of bacteria species and their grouping with complexes make endodontic infections even far more complex to the immune system response [6], which can lead to different clinical symptoms [5]. Socransky et al [7] was the first to group bacteria species into complexes, simplifying their description and relationships between different microbial groups in the infections (i.e. red, green, orange, secondary orange, purple, yellow). The red bacterial complex, which includes Treponema denticola, Tannerella forsythia and Porphyromonas gingivalis, has been recognized as a ‘disease-related’ complex [8]

Methods

Results

Conclusion