Evaluation of Bacterial Enumeration of CariScreen Versus Traditional Selective Culture

Purpose: The purpose is to evaluate whether the CariScreen meter is a reliable tool in quantifying cariogenic bacteria and a valuable addition to caries risk assessment.Methods: Sixty children, aged 6-17 years, were recruited. Caries status was recorded utilizing ICDAS system. CariScreen scores were evaluated from two sites: the lingual surfaces of the mandibular anterior dentition per manufacturer’s instruction and the mandibular buccal surface of one posterior molar. Stimulated saliva samples were collected for bacterial enumeration (Mitis Salivarus plate for total oral streptococci, Mitis Salivarus Sucrose Bacitracin plates for Mutans Streptococci (MS), Rogosa tomato juice plates for Lactobacillus (LB), and Blood agar plates for total viable bacteria). Statistical analysis was conducted using SPSS 22.Results: CariScreen scores from anterior and posterior sites revealed a moderate correlation (Correlation Coefficient = 0.42). CariScreen scores for both anterior and posterior sites revealed poor correlation with logarithmic counts of Mutans Streptococci, Total oral streptococci, Lactobacilli, and total viable bacteria (Pearson Correlation coefficient between -0.30 to 0.03, P>.02 for anterior sites and between -0.10 to 0.18, P>.18 for posterior sites). For anterior sites, caries-free subjects had higher log CariScreen scores than caries-active subjects (meanSE as 3.780.11 and 3.340.06, respectively, P=.12) while, for posterior sites, caries-free subjects’ log CariScreen scores were similar to caries-active subjects (meanSE as 2.950.19 and 3.060.08, respectively, P=.76). There were acceptable sensitivities (66-70%), but poor specificity (33-37%) and high false positive rate (45-75%) in diagnosing MS, LB and MS+LB levels compared with gold standard culture methods.Conclusion: Compared to bacterial culture, CariScreen meter showed poor prediction of cariogenic bacteria levels. Furthermore, CarieScreen scores in anterior sites reveal a trend of negative correlation to cariogenic bacteria levels and caries status