title: Penetration of ions from silicate cement restorations into Copalite--covered cavity walls.
abstract: This study aimed to asses the effect of silicate cement on Copalite -covered cavity walls in extracted human teeth. Class V cavities were prepared in 24 premolars and filled with silicate cement (Bio-Trey). Four cavities were unlined, the rest of the cavities were lined with 1 or 2 layers of Copalite before insertion of the restorations. After 6 months, 70-100 microns thick longitudinal sections of the teeth were studied by polarized light microscopy, microradiography and electron probe microanalysis. When imbibed in water or quinoline, a subsurface zone of altered birefringence was noticed in nearly all cavity walls. Nearly half of the cavity walls in the experimental groups showed a surface zone of increased radiopacity. In a few instances a subsurface radiolucent zone was present. By electron probe microanalysis F (0,4-3% by weight), Zn (1-4%) and Al (0,2-6%) were measured in the outer 10-60 microns of the cavity walls. The study shows that even with a double layer of Copalite, known to prevent microleakage, a desirable uptake of F and Al from silicate restorations into cavity walls can take place. Copalite does not prevent a phosphoric acid effect on the cavity walls.
mesh_terms: D000535:Aluminum / Q000378:metabolism*; D003736:Dental Cavity Lining; D003743:Dental Enamel / Q000378:metabolism*; D003804:Dentin / Q000378:metabolism*; D005459:Fluorides / Q000378:metabolism*; D006801:Humans; D012823:Silicate Cement / Q000378:metabolism*; D015032:Zinc / Q000378:metabolism*
chemical_list: D012823:Silicate Cement; D000535:Aluminum; D015032:Zinc; D005459:Fluorides