Effect of photodynamic antimicrobial chemotherapy on in vitro and in situ biofilms.

AIM: The effect of photodynamic antimicrobial chemotherapy (PACT) on oral biofilms was evaluated. METHODS: Biofilms formed in vitro were treated with sensitizer (S) and/or light (L) in the test (S+L+) and control (S-L-, S+L-, S-L+) groups. Additionally, 21 volunteers wore intraoral devices and the biofilms formed on each side of the device were referred to as S+L+ or S-L- groups. RESULTS: Significant decreases in the viability of in vitro biofilms were observed after PACT. PACT was ineffective in inhibiting multi-species biofilms formed in situ. CONCLUSION: PACT was effective on in vitro biofilms and was ineffective on in situ biofilms.