Effects of bactericidal treatments on bacterial adherence and dental plaque formation

In vivo plaque formation was significantly reduced when tooth surfaces were subjected to topical applications of iodine (0.2% I2 in 2.0% KI) twice daily for 3 d. Similarly, in vivo plaque formation was significantly reduced on enamel surfaces that were subjected to ultraviolet irradiation. Control experiments indicated that neither ultraviolet irradiation nor iodine treatment interfered with mechanisms for bacterial apposition to dental plaque. The results are interpreted to suggest that plaque grows in mass primarily by the division and multiplication in situ by plaque bacteria, not by a continued apposition of salivary microbes.