Detection of endodontic pathogens using Benzoyl-dl-Arginine-Naphthylamide (BANA) in infected root canals

Original research

Abstract

Aim:

Culture based identification techniques and molecular techniques are elaborate and a simple quick chairside rapid test will enable quicker detection of endodontic pathogens. The aim of this study was to determine the hydrolysis of BANA with standard strains of common endodontic pathogens in vitro and also the diagnostic accuracy of BANA in detecting microorganisms from infected root canal system in vivo.

Materials and Method:

The study was conducted in 2 phases. In the first phase, in vitro hydrolysis of  BANA by ATCC strains of common endodontic pathogens were evaluated. After BANA testing, intensity of colour change was noted at different incubation time of 4,6 and 18 hours. In the second phase,intracanal samples from each tooth (Pre-cleaning and shaping, Post- cleaning and shaping) were collected from 85 patients and subjected to both BANA and culture methods simultaneously. The results were tabulated and analyzed using measures of diagnostic validity.

Result:

In phase one testing, Porphyromonas gingivalis and Fusobactrium nucleatum showed strong positive reaction at overnight incubation on 1:20 dilution whereas it showed weakly positive reaction at 1:40 and 1:60 dilution. Pseudomonas aeruginosa showed weakly positive reaction at 1:20 dilution at overnight incubation whereas no color change at all other dilutions. Pre-cleaning and shaping diagnostic accuracy of BANA was 69.41% (95%CI, 59%- 79%). Sensitivity and positive predicative value for samples prior to cleaning and shaping was 75% (95%CI) and 80%( 95%CI) respectively.

Conclusion:

Porphyromonas gingivalis, Fusobacterium nucleatum, Pseudomonas aeruginosa, E. coli responds to BANA except Candida albicans. BANA has 69.41% of clinical diagnostic accuracy in detecting aerobic and facultative anaerobic bacteria present in teeth with necrotic pulps.