ROLE OF CHELATION IN DECALCIFKWTION SYSTEMS 

 180 



O 

 Q. 



CM 

 O 



MINUTES 60 120 



Fig. 3. Respiration of pioteol) tic bacteria isolated from a human mouth and 

 grown in the presence of different amounts of human enamel. (Courtesv of 

 Dr. Albert Schatz and the New York State Dental Journal.) 



therefore, prove tliat the organic matter of the hard tissues was 

 attacked l^efore decalcification, nor that the mineral matter had 

 been dissolved bv chelation. Also, in some of the experiments (es- 

 pecially with ground enamel and dentine), some of the organic 

 matter is quite freelv soluble (Stack, 1955; Evans and Prophet, 

 1950), and its release does not necessarilv prove proteolvtic action. 

 There is no reason to doubt that many of these products of proteol- 

 ysis are chelating agents. It is, however, impossible to decide how 

 effective these are or what proportion of the mineral matter which 

 dissolved did so bv chelation. Other workers whose results have 

 been quoted in support of the proteolysis-chelation theory of caries 

 are Saito (1957), Stiiben (1959), Wandelt (1959), and Eggers Lura 

 (1949, 1957, 1961). In our view all their results are inconclusive as 

 far as caries is concerned, either because their experiments were 

 inadequately controlled (Wandelt and Eggers Lura) or because 

 they did not reproduce conditions of saturation with calcium phos- 

 phate which resembled those in saliva. 



