Method: Twenty-five subjects with moderate gingival inflammation (Löe and Silness Gingival Index ≥2) and pocket depths <4 were randomly assigned to brush twice daily for 21 days with the test (Livionex Dental Gel, Livionex Inc., Los Gatos, CA) or the control dental gel (Colgate TotalR Dental Gel, Piscataway, NJ). On Days 0, 7, 14 and 21, plaque levels (Quigley-Hein, Turesky Modification Plaque Index), gingival inflammation (Löe and Silness Gingival Index) and gingival bleeding (modified Sulcus Bleeding Index) were determined by one standardized blinded investigator using a pressure sensitive probe. In vivo Nonlinear Optical Microscopy (NLOM) was performed using a novel prototype probe.
Result: After 3 weeks, all 3 clinical indices were significantly improved in both groups (P<0.05) and significantly lower in the test group (P<0.05). NLOM images showed a macroscopic break-up of the plaque layer and smaller, fragmented residual deposits in both groups, with smaller and fewer areas of residual plaque in the test group and no apparent changes in the pellicle.
Conclusion: A novel in vivo NLOM probe allows for high-resolution in vivo mapping of oral biofilm and assessment of the anti-plaque effectiveness of specific interventions.