EFFECT OF SUCROSE INTAKE AND GROWTH-CONDITIONS ON NUMBERS OF DENTAL PLAQUE BACTERIA EXPRESSING PROTEOLYTIC ACTIVITY

Proteolytic enzymes in dental plaque are important elements in the pat hophysiology of periodontal disease and are putative virulence factors . The effect of sucrose intake versus a sucrose-free diet (substitutin g glucose for sucrose) on numbers of isolates from early dental plaque expressing extracellular proteolytic enzymes able to hydrolyse gelati n and azocoll was studied. The bacteria were isolated from 0-3 d denta l plaque formed on the buccal surface of a lower premolar in six subje cts. A total of 7987 isolates were tested. Sucrose intake was associat ed with lower numbers of isolates expressing proteolytic activity at t he start of plaque formation and higher numbers in 2 and 3 d plaque. L imitations of current methods for cultural studies of developing denta l plaque are discussed, and the need for improved methods to study the nature and activities of all microorganisms colonising the teeth is s tressed.