The removal of carbon particles from the buccal surface of upper incisors and canines (by saliva and mechanical movement).

Clearance time of carbon particles from the buccal surfaces of upper incisor and canine teeth was measured, and its possible relationship with plaque accumulation and gingival inflammation was assessed. The average clearance time observed was 20.75 minutes. Factors influencing particle removal were found to be significantly related to the severity of gingival inflammation but not to differences in plaque accumulation. Thus the factors involved in particle clearance may modify the gingival response to plaque. Alternatively, small changes in gingival contour as a result of the inflammatory process may alter significantly the ability of these factors to remove particulate matter.