Antibiotic susceptibility of bacterial isolates in gingivitis and periodontitis.

The present study was conducted to isolate aerobic as well as anaerobic microbes from patients of gingivitis and adult periodontitis and to study the susceptibility patterns of these isolates to different antibiotics. In our study all the samples belonging to the control as well as the study groups yielded microbes. Aerobes and facultative anaerobes were isolated from 100 percent and 96 percent cases of normal gingiva and orodental infections respectively. Anaerobes were isolated from 80 percent of the normal gingival samples and 97 percent of the cases of orodental infections. Metronidazole was found to be the best for the anaerobes while the aerobes and facultative anaerobes showed good susceptibility to cefazolin and cefotaxime.

Polymicrobial etiology of dental caries.

The present study was carried out to establish the normal bacterial oral flora and the aerobic and anaerobic bacterial flora from deep seated dental caries, and to determine the antimicrobial sensitivity of the clinical isolates so obtained Streptococcus mutans (48%) and Streptococcus sanguis (20%) were the main aerobic isolates whereas Lactobacillus spp. (52%), Veillonella spp. (24%) and Actinomyces spp. (12%) were the major anaerobic isolates. Hundred percent of the samples from dental caries yielded polymicrobial isolates while in two samples from healthy individuals S. mutans was the sole isolate. As the flora changed from healthy tooth to dental caries it changed from one predominated by anaerobic gram-positive cocci to anaerobic gram-positive bacilli. All the anaerobes isolated were sensitive to metronidazole and cefotaxime, whereas all the isolated streptococci were sensitive to penicillin, erythromycin and clindamycin. Incorporation of the antibiotics in baseline restoration, if technically feasible, has been advocated.