Dental Caries and Periodontal Disease Considered as Infectious Diseases

Virulence of Streptococcus mutans: An Antibiotic-Suppressed Rat Model for Studies of Pathogenesis

“…Noninfected, antibiotic suppressed rats (Group C) were essentially cariesfree. These results demonstrate that: (1) COBS/CD rats harbor an indigenous oral flora which has some cariogenic potential; (2) antibiotic-suppressed rats are more susceptible to S mutans colonization; (3) the carious lesions observed in anti-, biotic-suppressed rats resulted from S mutans pathogenesis; and finally, (4) S mutans 6715 is cariogenic in COBS/CD rats and can cause significant caries within 20 days in animals fed a caries-promoting diet containing 5% sucrose.…”

“…The purpose of the present investigation was (1) to develop a simple and effective method for assessing antibiotics which inhibit total microbial growth of oral and fecal cultures from individual rats, (2) to suppress the total indigenous flora of rats by providing purified diet supplemented with the most effective antibiotics demonstrated by the in vitro technique and finally, (3) to determine the suitability of this antibiotic-suppressed rat model for study of S mutans pathogenesis.…”

Presence of an Invertase-Like Enzyme and a Sucrose Permeation System in Strains of Streptococcus mutans

“…Untreated sucrose grown cells exhibited 10-fold higher total 'sucrase' activity than did un treated glucose grown cells, suggesting that growth in sucrose broth resulted in the induction of a sucrose transport system. Strains of Streptococcus mutans are able to initiate microbial dental plaques and carious lesions in experimental animals fed diets containing sucrose [reviewed by Keyes, 1968;G old, 1970]. This organism synthe sizes extracellular glucans and fructans specifically from sucrose, and the glucans in particular are believed to be responsible for enabling this or ganism to adhere and accumulate on the tooth surface [reviewed by F itz gerald and J ordan, 1968; G ibbons, 1968].…”