بررسي باكتريولوژيك عفونتهاي ريشه دندان و نسوج پريودونتال

A STUDY OF PERIODONTAL TISSUE & ROOT CANAL BACTERIAL INFECTIONS

Dental and periodontal abscesses, because of their proximity to many important anatomic sites, can cause several dangerous and dreadful disorders. This study was carried out to investigate the causative organisms of dental and periodontal infections. Pus samples from fifty dental abscesses, were collected by needle aspiration and examined by direct inoculation techniques using different aerobic and anaerobic culture systems. In addition, for finding of the presumptive relation between the causative agents of dental infections and commensual organisms in the oral cavity, 50 swab samples from free gingival sulcus of individuals with apparently healthy dental and periodontal tissues were collected. The most common site of involvement was the first upper premolar tooth. Anaerobic infections were found in 38 samples (76%), and in 34(68%) of them, mixed cultures of aerobic and anaerobic bacteria were isolated. Anaerobic gram negative bacilli (black - pigmented bacteroides species) were the most common isolates. Aerobic bacteria were isolated in 46(92%) of the patients, with Streptococcus viridans being the most prevalent isolate. In samples obtained from the healthy dental tissues, aerobic bacteria were the most common isolates. In addition to this, the anaerobic bacterial flora isolated from dental infections and healthy tissue samples were significantly different(p< 0.05). Dental infections are the result of very complex microbial flora in which both aerobic and anaerobic bacteria play important roles in initiating the infection and it seems that the pathogenic bacteria and the commensual flora in healthy dental tissues have a great degree of similarities.