Fluoride uptake around cavity walls; two-dimensional mapping by electron probe microanalysis.

This study reports fluoride uptake around the cavity wall of teeth by two-dimensional mapping. Fluoride concentration was measured using the wavelength dispersive x-ray analysis (WDX) method. The buccal cavity wall of a human tooth was coated five times with 2% sodium fluoride solution at three-day intervals for 12 days, and then immersed in a normal saline solution at 37 degrees C. After one month, the tooth was bisected longitudinally through the center of the cavity surface perpendicular to the axial wall. On the polished surface of the cut tooth, the fluoride concentration was measured. Fluoride distribution maps around the cavity wall were drawn using a bundle of the observed analytical lines. Fluoride uptake from fluoride-releasing materials (conventional glass-ionomer cement, light-cured glass-ionomer cement, light-cured composite resin, light-cured bonding agent) around the cavity wall was investigated using the same method. The maps showed higher fluoride uptake in dentin than in enamel and a strong location dependence of fluoride uptake in a tooth, especially in the dentin. Fluoride uptake from the resin was greater than that from the cement. It was summarized from these results that a two-dimensional map of fluoride uptake can provide valuable information on the cariostatic properties of fluoride-releasing materials.

[Two-dimensional echocardiographic evaluation of the common pulmonary venous chamber in total anomalous pulmonary venous connection].

Morphology of the common pulmonary venous chamber and its spatial relationship to the left atrium were investigated in 19 patients with total anomalous pulmonary venous connection using two-dimensional echocardiography. The subjects were 12 males and seven females, ranging in age from newborn to 11 months with a median age of 34 days. Nine of the 19 patients were less than one month; 15 of 19 were less than two months. Ten patients had the supracardiac type (type I); three, the cardiac type (type II); and six, the infracardiac type (type III). To image the common pulmonary venous chamber the suprasternal short-axis coronal plane was used. The chamber was recorded simultaneously with the right pulmonary artery. A more anterior angulation for this view facilitated imaging the left atrium. The outlines of both the chamber and left atrium were traced. We calculated (1) the ratio of the width to the height of the chamber (W/H), (2) the angle made by the direction of the long-axis of the chamber and a horizontal line (Axis), (3) the quotient of the distance from the center of chamber to the bottom of the left atrium divided by the longitudinal dimension of the left atrium (B/A) and (4) the product of the width and height of the chamber (W x H). The W/H was 1.94 +/- 0.29 (type I); 1.21 +/- 0.27 (type II); and 0.63 +/- 0.15 (type III). There were statistically significant differences (p less than 0.01) among all types. The width was greater than the height in types I and II, but the height was greater than the width in type III. Axes were -19.0 +/- 5.7 degrees (type I); -5.1 +/- 5.0 (type II); and 91.7 +/- 9.3 (type III). There were statistically significant differences between all of the types (p less than 0.01). The long-axis was horizontal in types I and II, and vertical in type III. The B/A was 0.74 +/- 0.13 (type I); 0.57 +/- 0.10 (type II); and -0.04 +/- 0.30 (type III). There was a significant difference between type III and all other types (p less than 0.01). The common pulmonary venous chamber was located slightly superiorly to the left atrium in types I and II, but it was located inferiorly to the left atrium. In the six patients with type III, both lower pulmonary veins were located more inferiorly than the lower border of the left atrium.(ABSTRACT TRUNCATED AT 400 WORDS)