Effect of Water on Bonding of One-bottle Self-etching Adhesives

Abstract

This study evaluated the effect of water on dentin substrate bonding of one-bottle self-etching adhesives. Dentin substrates were divided into two groups: wet and dry dentin. Wet dentin is the normal substrate for bond testing whereas dry dentin was dehydrated in a desiccator for 24 hours. Bonded dehydrated teeth were then divided into two subgroups: stored in water or in desiccator for 24 hours. Microtensile bond strength of resin to dentin was measured using three one-bottle self-etching adhesives. In addition, nanoleakage evaluation was performed through the analyses of SEM and TEM micrographs. The bond strength of dry-dentin group was significantly greater than that of wet-dentin. Further, the amount of nanoleakage within the adhesive interface of dry-dentin group was less than that of wet-dentin. Results showed that bond strength and nanoleakage formation depended on the bonding substrate (wet versus dry dentin) before bonding. One-bottle self-etching adhesives might suck the water from dentinal tubules during bonding by osmosis, leading to nanoleakage formation and thus a decline in bond strength.

Two-year Clinical Performance of Self-etching Adhesive Systems in Composite Restorations of Anterior Teeth

“…32 Water trees are water canals at the adhesive interface created by the highly osmolarity of the adhesive solution generating nanoleakage. [11][12][13] In vivo studies are in agreement with the current results, showing good results of 1-SEAs for marginal integrity. 1,21,22,24 With regards to postoperative sensitivity, one restoration bonded with Clearfil S3 Bond, one with Single Bond 2. and one with Optibond All-in-One showed postoperative sensitivity at the one-year recall.…”

“…9,10 Self-etching adhesive systems are also subject to hydrolysis caused by the high permeability of the adhesive layer (osmosis), which generates nanoleakage at the adhesive interface. [11][12][13] Some clinical studies have showed good clinical performance of two-step self-etching systems. [14][15][16][17][18] Recently, one-step self-etching adhesive systems (1-SEAs) were introduced as the seventh generation of etching systems, which combine acid conditioning, primer, and adhesive in one bottle.…”

Bonding of self-adhesive resin cements to enamel using different surface treatments: bond strength and etching pattern evaluations

“…Further, shear bond strength test revealed that with #600 polishing, self-adhesive resin cements failed to exhibit acceptable bond strengths. Minute amounts of water left in the smear layer and intrinsic water in enamel most probably led to limited ionization of the demineralizing monomers, which was one more indication that resin cements or adhesives are able to absorb water from their bonding surfaces through diffusion 26) . As for self-etching adhesive systems, their In (c, h), similar morphology was seen as BR and G-Bond contained the same adhesive monomer 4-MET.…”

Effect of smear layer characteristics on dentin bonding durability of HEMA-free and HEMA-containing one-step self-etch adhesives

“…Therefore, HEMA-free one-step self-etch adhesive systems have recently been introduced with the expectation of reducing water sorption and increasing the long-term stability of the mechanical properties. Ultrastructural observation of the adhesive interface of one-step self-etch adhesives has shown nanoleakage in the adhesive layer as well as in the hybrid layer 20,21) . Additionally, HEMA-free adhesives express water-tree nanoleakage formation above the resin-dentin interface due to phase separation of adhesive components and osmotic water infiltration as a result of water remaining on the dentin substrate or being transported from the dentinal tubules 15,22,23) .…”