A method for microleakage evaluation along the dentin/restorative interface.

F R Tay; K M Pang; A J Gwinnett; S H Wei

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PubMed · 7546479

A method for microleakage evaluation along the dentin/restorative interface.

F R Tay·K M Pang·A J Gwinnett·S H Wei

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Abstract

PURPOSE: To present a simple non-abrasive protocol in conjunction with the silver-staining method, enabling unobstructed visualization of well-defined microleakage patterns within the demineralized dentin-restorative interface. MATERIALS AND METHODS: Class V preparations were made with an occlusal margin on bevelled enamel and a gingival margin on dentin/cementum. After restoration with All Bond 2/P-50 and Scotchbond 2/Silux, storage in water at 37 degrees C for 7 days and thermocycling 300 times between 5 degrees and 55 degrees C, the specimens were placed in silver nitrate solution. After silver fixation, demineralization and clearing in methyl salicylate, silver stain location was scored ordinally. In addition, a three dimensional portrait of leakage pathways was illustrated using photographic and computer digitization. RESULTS: The Wilcoxon signed-rank test showed that the extent of silver penetration before and after acid demineralization was not significantly different (P > 0.05). This study also confirmed that microleakage is not uniform along the circumference of a restorative margin. Although the protocol is insensitive to microleakage occurring solely within enamel, the predominant concern over that occurring within dentin, in particular along the cervical restorative border, renders it a serviceable alternative for future investigation of the integrity of the marginal seal from clinically restored in vivo specimens.

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Acid Etching, Dental Bicuspid Bisphenol A-Glycidyl Methacrylate Composite Resins Decalcification Technique Dental Leakage Dentin Dentin-Bonding Agents Humans Methacrylates Molar, Third Resin Cements Silver Staining Statistics, Nonparametric Tooth Root Journal Article

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F R Tay, K M Pang, A J Gwinnett, S H Wei. 1995. A method for microleakage evaluation along the dentin/restorative interface.. https://pubmed.ncbi.nlm.nih.gov/7546479/

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