Antibiotic Resistance Profile of Biofilm Forming Streptococcus mutans Associated with Dental Caries in Osogbo, Osun State, Nigeria

Abstract

Streptococcus mutans (S. mutans) has been implicated as the primary microbial pathogen associated with dental caries. The financial and economic burden, together with loss of productivity experienced due to dental caries, are of significant concern. This study aims to isolate S. mutans from decayed teeth and dental plaque samples obtained from government hospitals and their surrounding areas. S. mutans was isolated and presumptively identified with morphological, biochemical, and polymerase chain reaction (PCR) amplification of species-specific primers for S.
mutans. The isolates were tested for their ability to produce biofilm and the presence of biofilmforming genes (glucosyltransferases (gtfB) and (gtfC)). The susceptibility of the isolates to antibiotics of choice was carried out with Kirby Bauher disc diffusion methods. A total of ninety-six (96) S. mutans isolates were isolated and presumptively identified with morphology and biochemical tests.
Sixty-three of the isolates (66%) were identified as S. mutans with specie-specific gene with a band at 1272 bp. Biofilm assays indicated that 53 of the isolates (84%) were biofilm formers, while 43 (68%) were strong biofilm formers. The biofilm genes 47 (75%) had the gtfB gene and43 (68%) possessed the gtfC gene were detected in the isolates. All the isolates were resistant to penicillin G and clindamycin and some were susceptible to piperacillin, imipenem, and ciprofloxacin. In addition, some of the isolates were resistant to Ampicillin while some were susceptible to Ampicillin. These findings suggest that imipenem, piperacillin, and ciprofloxacin could serve as best control methods for dental caries infection.