Abstract
For researching the anti-carious action of stannous fluoride, it seems to be one of the important problems to detect histochemically tin in dental enamel. However, the present knowledge on the location of tin in tissue is very poor, particularly in dental enamel; it has never been observed.
For the purpose to establish a stable and applicable histochemical method for tin in dental enamel, an attempt was made to apply the Okamoto's histochemical method with phenyl trioxyfluoron-o-carbonic acid (gallein), which had been originally devised for soft tissues.
Freshly extracted teeth were employed in this experiment. A half dental crown was treated with stannous fluoride, while the other falf was remained untreated as the control, and the whole crown was stained with gallein solution. After being stained, the ground sections were made and observe to estimate the staining states of tin in enamel under the microscope.
Gallein-tin reaction found on sections appeared red as expected, but the enamel surface was partially decalcified with the strong acidity of the staining solution. The grade of decalcification seemed to be parallel with the staining capacity which was increased by the elevation of temperature or the elongation of staining time. Moreover, in these attacked sites, the color changed to yellowish-brown like a caries lesion owing to the impregnation by gallein.
Owing to this drawback, it was difficult to differentiate clearly the color between gallein and gallein-tin; hence the distinct localization of tin in or on the intact enamel surface was not detected.
From these experiences, the authors were forced to devise a new staining method for tin applicable to dental enamel and other hard tissues.
The details of the new method will be reported in the next paper.
