PHYSICO-CHEMICAL STUDIES ON THE STRUCTURE OF DENTAL ENAMEL

III. A METHOD FOR DETERMINING THE RATE AT WHICH A SALT MAY PENETRATE THE ENAMEL

¹ Department of Chemical Hygiene, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, Maryland

(1). An electrical method is presented by which conductivity changes in a tooth may be followed.

(2). The rate of penetration of salt may be studied by this method.

(3). The velocity at which a salt penetrates the enamel is shown to be dependent upon the existing osmotic gradient.

(4). The penetration of salt into the enamel of a dog canine is relatively slow, requiring eight hours with 1.0 M KC1 solution; twenty-four hours with 0.1 M KCI solution.