Abstract

Objective: To investigate the bacterial flora of the gingival plaques of pediatric dental patients in order to establish baseline data for future studies on the complex microbiota of the oral cavity of this group of child dental patients.

Subjects and methods: Forty subjects, aged 3-12 years, were enrolled and investigated after informed consent was obtained. During the patients' first visit to the dental clinic supragingival plaque samples were collected from the gingival area of buccal and lingual tooth surfaces of all primary and permanent molar teeth using sterile curettes. Serially diluted samples were inoculated onto a set of selective and nonselective media and then incubated at the appropriate atmospheric conditions and temperatures. Representative colonies of isolates were identified by standard methods, including hemolytic characteristics on blood agar and profiling on API 20S and API 20A as appropriate.

Results: A total of 183 isolates (123 aerobes and 60 anaerobes) were recovered from the 40 patients with a mean count of 3 per sample of aerobes compared to 1.5 per sample for the anaerobes. Streptococcus sanguis was the predominant aerobic species (23.6%) isolated from 29 (72.5%) of the 40 patients, followed by Streptococcus mitis, 19.5 and 60%, Streptococcus salivarius, 17.1 and 52.5% and Streptococcus mutans, 17.1 and 52.5%. The frequency of isolation of anaerobic bacteria was Prevotella spp. 50% from 30 (75%) of the 40 patients, Fusobacterium spp., 18.3 and 27.5%, Bacteroides spp., Porphyromonas spp. and Peptostreptococcus spp., 6.7 and 10%, 6.7 and 10%, and 5 and 7.5%, respectively. Prevotella intermedia was the single most common species.

Conclusion: The results show that there were more aerobic/facultative anaerobic bacteria than the obligate anaerobes in the dental plaque of the pediatric dental patients in Kuwait. The high prevalence of the pioneering streptococci as well as black-pigmented Prevotella spp. and Fusobacterium spp. indicates that the dental plaques of the children were in the developing stage, a precursor to the development of periodontal diseases.