Effect of antimicrobial photodynamic therapy on the counts of salivary Streptococcus mutans in children with severe early childhood caries.

BACKGROUND: Antimicrobial photodynamic therapy (aPDT) is a novel technique for reduction of pathogenic microorganisms in dentistry. The aim of this study was to evaluate the effects of aPDT on Streptococcus mutans reduction in children with severe early childhood caries. METHODS: Twenty-two children with severe early childhood caries aged 3-6 years were treated with toluoidine blue O (TBO) for 1min and irradiated by a Light Emitting Diode (LED; FotoSan, CMS Dental, Denmark) with the exposure time of 150s. Saliva samples were collected at baseline, 1h and 7 days after treatment. S. mutans counts were determined using the Dentocult SM Strip mutans. RESULTS: The counts of S. mutans in saliva decreased significantly after 1h (P<0.001). However, the difference in reduction of S. mutans counts in saliva was not significant between the baseline and 7 days after treatment (P>0.05). CONCLUSION: aPDT seems to be efficient to reduce salivary S. mutans immediately after treatment in children with severe early childhood caries. However, further research is needed to evaluate different doses and frequency of irradiation in combination with restoring carious teeth to find more durable results.