Abstract
It has been reported in our laboratory that a bacteriolytic enzyme fromStreptomyces globisporusstrain 1829 possessed marked bacteriolytic activity against various strains of cariogenic plaque bacteria.
The purpose of the present investigation was to determine the effects of the enzyme on plaque accumulation, caries development and alveolar bone resorption in hamsters infected withStreptococcus mutans.
An NIH (U.S.A.) strain of golden hamsters weighing around 50gr. was infected orally with the Brain Heart Infusion broth cultures of streptomycin-resistant strains ofS. mutansAHT-R or K1-R and fed cariogenic Diet it 2000 with or without addition at 0.025 or 0.1% (w/w) of the bacteriolytic enzyme. After rearing on the diets for 34 days (AHT-R) or 30 days (K1-R), the animals wete sacrificed and the extents of plaque, caries and alveolar bone loss of the molar dentition were estimated.
When the hamsters inoculated with strain AHT-R or K1-R were provided with Diet it # 2000 without the enzyme, a large amount of microbial plaques were deposited around the molars, and rampant dental caries and alveolar bone resorption were extensively developed. The extent of the carious lesions of the molars were in the following order: M1<M2<M3. Neither plaque formation not the pathologic changes of tooth and alveolar bone could be observed in the non-infected control hamsters.
By addition of the bacteriolytic enzyme to the diet at 0.1%, the plaque formation was reduced, and the caries development and the bone resorption were inhibited with statistical significance, but this suppression was not observed in the case of supplement with 0.025% enzyme.
