FACTORS INFLUENCING DENTAL CARIES 



273 



•sv 



?^^;^""•k^ 





Fig. 6. Decalcified sections of carious lesions in the hamster. A, placjue (1) 

 formation in the gingival sulcus associated with massive invasion of enamel (2); 

 and characteristic spread along the junction of enamel and dentin (3). B, Gram- 

 positive spherical organisms invading enamel. C, cross sections of dentinal 

 tubules filled with Gram-positive cocci. D, tubular invasion often can be fol- 

 lowed for considerable distances in the dentin. Only coccoid forms of organisms 

 have been found in the depths of lesions, approaching the pulp, and far in 

 advance of generalized necrosis. Photographs B, C, and D were taken under 

 oil immersion. 



