Studies on human dental plaque. 3. Variation of protein constituents among individuals

Separate plaque samples (collected from 13 patients who had experienced caries and various degrees of periodontal disease) were each dispersed in 1 ml of distilled water, homogenized and lyophilized. Each lyophilisate was extracted in 1 ml of buffered saline, concentrated and analyzed. Enzyme activity studies revealed amylase in all plaque samples. Lysozyme was present occasionally. By radial immunodiffusion, IgG and IgA were shown to be in plaque extracts of some patients. Immunofluorescence examination of the sediments of individual plaque samples revealed that IgG and IgA occurred frequently. Polyacrylamide gel electrophoresis patterns of the extracts of plaque from different individuals exhibited marked variability despite some zones of similarity. Peptide maps of the dialysable material of the individual plaque extracts were remarkably similar.