Enamel demineralization inhibition by cements at orthodontic band margins

To examine the demineralization inhibition effects of glass ionomer cement and polyacid-modified resin-based composite cement, in comparison to non-fluoride releasing zinc phosphate cement.

Twenty-seven extracted molars were obtained and randomly assigned to three groups. An orthodontic band was sized and cemented using one of three cements. The teeth were painted with an acid-protective varnish, excluding a 1 mm area gingival to the orthodontic band. The teeth were placed in separate closed environments of a non-fluoridated acid challenge to induce demineralization for 5 days. The teeth were then sectioned two times buccolingually and two times mesiodistally. The sections were photographed with polarized light microscopy in an imbition media of water. The body of each lesion was measured with a computerized imaging system. The areas of the lesions, from each cement group, were compared.

An analysis of variance (ANOVA) indicated significance in variance among groups (P < 0.001). Results of a multiple comparison analysis demonstrated significantly less demineralization adjacent to the glass ionomer cement group compared with the polyacid-modified resin cement group and non-fluoride releasing zinc phosphate control group (P < 0.05). There was no significant difference in adjacent demineralization inhibition between the zinc phosphate cement group and polyacid-modified resin cement group (P < 0.05).