Qualitative and quantitative molecular analysis of bacteria in root canals of primary teeth with pulp necrosis

Abstract

Information about bacterial diversity, such as the number of each species in the root canals of primary teeth, contributes to improving our effective management of infections of endodontic origin in primary teeth. This study made a qualitative and quantitative assessment of the bacteria in the root canals of primary teeth with necrotic pulp, using the fluorescence in situ hybridization (FISH) technique. Thirty-one primary teeth with pulp necrosis from 31 children were evaluated using the FISH technique, to detect the presence and density of Aggregatibacter actinomycetemcomitans, Campylobacter rectus, Enterococcus faecalis, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Prevotella nigrescens, Streptococcus, Streptococcus mutans, Streptococcus sobrinus, Tannerella forsythia and Treponema denticola. Descriptive measures explained the data related to density, and Student's t-test assessed the differences among the densities of each bacterium, according to signs and symptoms. The bacterial density was paired and correlated. All bacteria tested were detected and identified in all the samples. The average number of bacterial individuals from each species ranged from 1.9 x 10 8 cells/mL (S. mutans) to 3.1 x 10 8 cells/mL (F. nucleatum) (p > 0.05). The sum of the mean counts of each bacterium represented almost 80% of the entire microbial community. Patients with pain had significantly more T. denticola, and those with edema showed a greater density of Streptococcus and P. nigrescens (p < 0.05). This study revealed that all 12 bacteria evaluated were found in all primary teeth with pulp necrosis. There was no predominance among the species studied; all species had a similar number of individuals.

Comparative Evaluation of the Antibacterial Efficacy of Aloe Vera, 3% Nano Silver Solution, and 2% Chlorhexidine Gluconate on Enterococcus faecalis: An In Vitro Study

“…However, sodium hypochlorite (NaOCl) is considered the widely used endodontic irrigant solution but it has numerous disadvantages such as bad taste, toxicity, and risk of tissue destruction and denatures, as well as the inability to eliminate all the microorganisms present in infectious canals. Chlorhexidine (CHX) gluconate can be applied clinically as an antimicrobial agent alone or in combination with NaOCl during all phases of the root canal preparation (4) .…”

“…However, the endodontic infections have a polymicrobial nature but it was found that Enterococcus faecalis (E. faecalis) is one important microorganism to be controlled as it observed in 22% and 32% of necrotic deciduous teeth and it is more prevalent in secondary infection than in primary endodontic infections. Additionally, it has been considered as the most antibioticresistant and the most common species recovered from teeth with failed endodontic treatment (4) . However, no irrigant solution appears to be ideal as a disinfectant solution against E. faecalis.…”

Actividad antibacteriana de los materiales de obturación radicular utilizados en terapias pulpares de dientes temporales. Estudio in vitro

“…(9,10,15) Muchos investigadores han demostrado que existe una gran diversidad bacteriana en piezas dentarias con necrosis; en dientes permanentes se han aislado microorganismos como: Streptococcus salivarius, Streptococcus mutans, Staphylococcus aureus, Neisseria catarrhalis, Lactobacillus casei, Pseudomonas aeruginosa, Candida albicans, Enterococcus faecalis entre otros (9,10,15) . En dientes temporales se han aislado microorganismo como: Streptococcus salivarius, Streptococcus muntans, Streptococcus sobrinus, Prevotella intermedia, Provotella nigrescocens, Porphyromona gingivalis, Treponema denticola, entre otros (16,17,18) . Pero las bacterias anaerobias facultativas son las especies dominantes involucradas en este proceso, entre ellas, el Enterococcus faecalis que también es considerado como el microorganismo más resistente y responsable de los fracasos de los tratamientos pulpares en dientes temporales y permanentes.…”