Oral Bacteria In 1-yr-old Infants With Very Low Birth Weights

Objective: The aim of the study was to identify the representative cariogenic and periodontal bacteria in 12-month-old infants and to compare their occurrence between a cohort of very-low- birth- weight infants (VLBW) and a control cohort of full-term children. Methods: Totally, 86 one-year-old infants were examined, 44 VLBW and 42 full-term infants. Smear samples from the dorsum of the tongue and dental plaque were collected in both groups and processed for identification of cariogenic and periodontal bacteria using a real time PCR method. In addition smears were cultivated on MSA-bacitracin plates and colonies resembling mutans streptococci were isolated for testing their phenotype metabolic properties. Chi-square and Fisher’s tests were used for statistical evaluation of data of both VLBW and control cohorts. Results: At least one species of cariogenic bacteria were detected in 82.3% of the VLBW infants and in all the full- term infants. Periodontal pathogens were found in 61.8% of the pre-term infants and 89.6% of full-term infants. Significant differences between the cohorts were found in terms of the presence of Streptococcus mutans (SM). While in control cohort S. mutans was present in all children, in the VLBW cohort it was identified only in 3.8% of children (p=0.0001). Lactobacilli were identified in 87.7% and 91.2% of VLBW and control children, respectively (p=0.276). Aggregatibater actinomycetemcomitans was found in 63.5% and 65.8% of VLBW and control children rep. (p=0.173) and Fusobacteria and Capnocytophaga were present in less than 40% equally in both cohorts. Conclusion: This study confirmed the early transmission of cariogenic and periodontal pathogens to the oral cavity of one-year-old infants. The presence of cariogenic bacteria in the oral cavity represents a risk factor for the caries development. The clinical significance of oral periodontal pathogens occurrence at such a young age is the matter of future research.