The influence of gingival inflammation on de novo plaque formation.

The aim of the present clinical trial was to examine the influence of gingival inflammation on de novo plaque formation. In addition, the effect of a varying number of salivary bacteria on early plaque formation was evaluated. 10 subjects were recruited for the trial which was designed to establish 2 different starting points for de novo plaque formation, 1 in a healthy dentition and 1 in a gingivitis dentition. On Day 0 and at regular intervals during a 5-week period, the panelists were examined with respect to gingivitis, plaque and number of salivary bacteria. The findings from the study demonstrated that the condition of the marginal gingiva plays an important role in the early stages of plaque formation. Thus, in both phases of the study, it was observed that at sites with initially healthy gingival units, less plaque formed (PlI = 0.93 and 0.82) than at sites with GI > 0 (PlI = 1.24 and 1.28) at the 2 different starting points. The number of salivary bacteria seemed to be less important than the state of the gingiva for the amount of plaque that formed during a 4-day period of no active mechanical tooth cleaning.