Bonding performance of different adhesive systems to deproteinized dentin: Microtensile bond strength and scanning electron microscopy

Abstract

Deproteinization has been shown to optimize dentin bonding, but differences in adhesive composition should be considered. The objective of this study was to evaluate the effect of dentin deproteinization on microtensile bond strength (microTBS) of four total-etch adhesive systems (Single Bond/SB, Prime & Bond NT/PB, One Coat Bond/OC, and PQ1/PQ). The ultrastructure of the resin-dentin interfaces was also examined using scanning electron microscopy. Tukey's multiple-comparison tests indicated that PB and PQ produced significantly higher microTBS (p<0.05) after dentin deproteinization (PB=61.53 MPa, PQ=58.18 MPa). This treatment provided statistically lower results for SB (39.08 MPa), but the microTBS of OC to dentin was unaffected by dentin deproteinization. The bonding performance on deproteinized dentin surfaces depended on the characteristics of each adhesive system, as well as the adhesive dentin specificity to the oxidant effect of sodium hypochlorite. Incorporation of fillers in the adhesive, a possible self-etching action, and the presence of a volatile solvent (acetone) were the main factors for a better union between the adhesive system and deproteinized substrate.

Compromised Bond Strength after Root Dentin Deproteinization Reversed with Ascorbic Acid

“…This type of failure is related to the degradation of exposed collagen that was incompletely covered by the adhesive (17). Therefore, it has been hypothesized that collagen removal with NaOCl might contribute to long-term adhesion stability (27,30). Such treatment is recognized to remove the organic matrix, leaving a clean mineralized surface (27,28).…”

“…It is possible that the deproteinizing process is less important than the redox effects of NaOCl and ascorbic acid to bond strength. Furthermore, the application of NaOCl after etching is opposite to the procedure used in clinical practice; this procedure has been evaluated in the literature as a possible method for minimizing the sensitivity of the hybridization technique (30,31).…”

“…This procedure has also been proposed as a method to improve adhesive wettability (29). However, the bonding performance on deproteinized dentin differs between adhesives (27,30,31). Therefore, it is crucial to compare new self-adhesive cements with conventional ones by using different adhesives.…”

EDTA or H3PO4/NaOCl dentine treatments may increase hybrid layers’ resistance to degradation: A microtensile bond strength and confocal-micropermeability study

“…42,55 In the case of acid-etched dentine, the complete deproteinization might hypothetically offer the possibility of an increase in the bond strength of resin-bonded dentine created by adhesives containing phosphate, phosphonate or carboxylic groups that are potentially capable of interacting with the Caions of the apatite crystallites of the dentine surface. 56,57 However, complete removal of the demineralized collagen matrix from acid-etched dentine using 12% NaOCl cannot be achieved in clinically realistic times of application but only after 30 min. 27,58 In the present study, no statistically significant difference exists between the mTBS values of Optibond Solo Plus and Scotchbond 1XT when applied on dentine pre-treated with 37% H 3 PO 4 /0.5% NaOCl and submitted to 12% NaOCl-challange for 90 min and their respective control groups ( Table 2).…”

Effects of Epigallocatechin-3-gallate (EGCG) on the bond strength of fiber posts to Sodium hypochlorite (NaOCl) treated intraradicular dentin

“…NaOCl treatment on dentin surfaces has been reported to be effective on deproteinizing the dentin surface and improving the adhesive wettability 20 . Therefore, some researchers have hypothesized that the collagen removal with NaOCl might contribute to long-term adhesion stability of resin-dentin 21, 22 . However, the use of NaOCl on post space pretreatment was also problematic considering its negative effect on the polymerization of the adhesive resin 23 .…”