Study Of Resazurin Disc Test In Caries Activity Test

Objective: To investigate the relationship between the scales of color variation of resazurin disc test(RD TEST) and the quantity of cariogenic bacteria in dental plaque.To provide solid evidence for prediction in caries activity by RD TEST.Methods: 56 children were applied and direct soakage RD TEST and the results were recorded. Every child's dmft were also recorded. The samples of saliva and dental plaque were obtained and diluted and respectively inoculated to the selective medium .The colony's CFU/ml was recorded. Applying SPSS FOR WINDOWS 11.0 to analyze the relationship between the scales of color variation of RD TEST and dmft, the quality of bacteria in saliva and dental plaque.Result: Both quantificational saliva and direct soakage RD TEST show positve relationship with the quantity of bacteria in saliva and dental plaque and dmft . The streptococci , S mutans,lactobacillus in saliva positively related to those in dental plaque. The sensitivity of both quantificational saliva and direct soakage RD TEST is 74%, the specificity of quantificational saliva RD TEST is 62%, and that of direct soakage RD TEST is 79%. There is no difference between both RD TEST.Conclusion: The caries activity can be predicted by color variation of RD TEST since it can present the quantity of bacteria in dental plaque.The simpler direct soakage RD TEST can replace the quantificational saliva RD TEST.