Ultramorphological Characterization of the Resin Dentin Interface – An in vitro Analysis of Nanoleakage Patterns of Dentin Adhesives

Aim and Design: The requirements of an effective dentin adhesive system include the ability to thoroughly infiltrate the collagen network and partially demineralized zone, to encapsulate the collagen and hydroxyapatite crystallites, to produce a well polymerized durable hybrid layer with high bond strengths. Microleakage and marginal percolation are the most detrimental factors thwarting the success of any restoration . However, the presence of leakage pathways, called nanoleakage have been observed in the hybrid layer,even in the absence of microleakage. The nanoleakage patterns of four dentin adhesives (Prime & Bond NT,AdheSE, Clearfil S3 bond and Fuji Bond LC) was compared using Scanning electron microscopy and Energy Dispersive Spectroscopy, by the silver nitrate penetration method.

Results and conclusion: The results indicated that etch and rinse adhesives showed the maximum nanoleakage followed by the self etch systems. The glass ionomer based bonding agents showed the least nanoleakage. It is extremely important to take nanoleakage as a consideration while choosing dentin adhesives, to ensure success of the restoration.

Bonding, nanoleakage, hybrid layer, etch and rinse, self etch, glass ionomer

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