THIAMINE CL-HCL EFFECT UPON ACID PRODUCTION AND UPON DEXTRINIZING TIME OF SALIVARY AMYLASE WITH CORN STARCH SUBSTRATE

¹ Forsyth Dental Infirmary for Children, Boston, Mass.

a. This study gives further evidence that the dextrinizing time, resulting from the action of salivary amylase on corn starch, and dental decay proneness are associated.

b. The addition of vitamin B₁ (thiamine Cl-HCl) to the saliva-corn starch mixture speeds the dextrinizing time. The speeding (expressed as a per cent) is significantly greater for the caries-resistant group than for the group which has experienced recent rapid dental decay activity.

c. The amount of titratable acidity from saliva and corn starch differs for the dental caries-free and caries-active groups.

d. When vitamin B₁ is part of the saliva-corn starch reaction mixture during incubation, the titratable acidities are higher in all groups than for saliva-corn starch alone, though not as high as the acidity figure for saliva-corn starch, plus the acidity figure for thiamine Cl-HCl.

e. The question is raised whether pH 6.9 is in fact the optimum pH for the amyloclastic phase of salivary amylase in such a medium as saliva-corn starch.