Evaluation of Two Salivary Test Kits Using Species-specific Antibodies

Objectives: Our previous study reported that the commercial salivary test kits we evaluated might be sensitive enough to be used for screening tests of mutans streptococci or lactobacilli (Ohmori et. al. IADR abstract #3452, 2004 and abstract #822, 2005). This study aimed to evaluate a performance of salivary test kits using species-specific antibody, ORAL TESTER (Tokuyama Dental, Japan) and SALIVA-CHECK SM (GC, Japan). ORAL TESTER was a newly developed product using a polyclonal antibody, while SALIVA-CHECK SM determines the number of S. mutans using a monoclonal antibody. These are capable of demonstrating their results within 30 minutes. Kits were compared to the cultivated test kit, Dentocult SM (Orion, Finland) in detecting mutans streptococci. Methods: Stimulated saliva was collected from 98 students (age 22-37, male 65, female 33). Saliva was placed on the attached strips of Dentocult SM and incubated for 48 hours. After cultivation, the colony density of each sample was evaluated. The same saliva was applied on the test sheet of SALIVA-CHECK and ORAL TESTER according to the manufacturer's instruction. Results were determined using the model chart. In addition, 100µL of saliva was diluted using a 10-fold dilution method and then placed on MSB agar plate, which was cultivated anaerobically for 48 hours. The number of colonies on MSB was counted, and the colony-forming-units (CFU/mL) were calculated. Results of each kit were round-robin tested, and compared to the MSB by which correlation coefficient was culculated. Results: Correlation coefficient (r) was 0.603 between ORAL TESTER and MSB, 0.458 between SALIVA-CHECK and MSB and 0.377 between Dentocult and MSB. Correlation (r) was 0.527 between ORAL TESTER and Dentocult, which was higher than 0.334 between SALIVA-CHECK and Dentocult. Conclusions: Results demonstrated that two kits using species-specific antibodies might be sensitive enough as the screening test with no need of cultivation time.