Evaluation of Shear-Bond-Strength of Dental Self-Adhering Flowable Resin-Composite versus Total-Etch One to Enamel and Dentin Surfaces: An In-Vitro Study

Abstract

AIM: This study aimed to assess the shear bond strength of a self-adhering flowable resin composite versus a total-etch one to different surfaces of permanent-molars.
 MATERIAL AND METHODS: Thirty-six sound human permanent molars were used. The teeth were embedded in acrylic blocks, such that their buccal surfaces were shown. The teeth were divided into three groups: Group I: Uncut-Enamel, Group II: Cut-enamel-surfaces with minimal-grinding and Group III: dentin-surfaces. Half of the teeth in each group were used for bonding to a self-adhering flowable resin-composite (Dyad-flow, Kerr, USA). While the other half of each group was bonded to a total-etch flowable resin-composite (Filtek™Z350-XT,3M-ESPE, USA) which necessitate etching and bonding. Teflon-mold was used for constructing resin composite cylinders (3 × 3 mm) over the buccal surfaces. The Dyad-flow was applied in the central hole of the mould placed upon tooth-surface, and then light-cured for 20 seconds. The Filtek-Z350-XT was applied similarly after etching and bonding steps. The teeth were stored in 37°C distilled water for 24 hours. The strength was measured using a universal testing machine and statistically analysed. Modes of failure were studied using digital-microscope.
 RESULTS: Mean values of shear bond strength for the Dyad and Filtek-Z350-XT in the uncut-enamel were 3.5 and 24.6MPa respectively, while that for cut-enamel were 4.5 and 12.7MPa respectively (Both highly statistically significant P ≤ 0.01) and in dentin were 4.3 and 6.7MPa respectively (Statistically significant P ≤ 0.05). The failure mode for Dyad was mainly adhesive (un-cut or cut-enamel 83.3% adhesive and 16.7% mixed, while in dentin 100% adhesive). While the modes of failure for Filtek-Z350-XT in enamel, either cut or un-cut, were 50% cohesive and 50% mixed, whereas in dentin 100% adhesive.
 CONCLUSION: Bonding of self-etch ″Dyad-flow″ flowable resin-composite was lower than the total-etch one in enamel and dentin. Thus further material improvement may be required.

Tooth sealing formulation with bacteria‐killing surface and on‐demand ion release/recharge inhibits early childhood caries key pathogens

“…These findings agree with previous work, who suggested that changes in the filler content may result in higher SBS (Kucukyilmaz & Savas, 2015; Singh, Kaur, & Kapoor, 2019). The shear bond values presented by the experimental formulations were similar or higher than shear bond values reported in the literature (Abdelraouf, Mohammed, & Abdelgawad, 2019).…”

Comparison of shear bond strength of etch and rinse, self-etch adhesive system followed by flowable composite resin, and self-adherent composite resin

“…Therefore, given all the consequences to the exposure of the collagen matrix by phosphoric-acid etching, this approach can be considered as an aggressive procedure to the dentinal structure. 3,6,7,9,10 The self-etch adhesive system had the second-highest bond value between the tested groups, with no statistically significant with the etch and rinse group. Its bonding property depends on a functional acid monomer, 10-methachryloylozydecyl dihydrogen phosphate (MDP) that interacts with the hydroxyapatite in the tooth.…”

“…The acidic monomer in the self-adherent composite, glycerolphosphate dimethacrylate (GPDM), is responsible for surface etching and chemical bond to calcium ions from the tooth by the acidic phosphate action, while the methacrylate component holds the polymerisation process and support the micromechanical interlocking mechanism between the monomer and demineralized collagen fibril of the dentin. 6,7,8 As stated before, that bonding to enamel and dentin have different challenges, a study on the self-adherent resin composite bonding ability showed that self-adherent flowable resincomposite had lower bond strength to enamel and dentin than the total-etch (etch and rinse) system. 7 In line with the mentioned results, bonding effectiveness of the self-adherent composite resin was also underscored to the self-etch adhesive system followed by the application of a flowable composite.…”

“…6,7,8 As stated before, that bonding to enamel and dentin have different challenges, a study on the self-adherent resin composite bonding ability showed that self-adherent flowable resincomposite had lower bond strength to enamel and dentin than the total-etch (etch and rinse) system. 7 In line with the mentioned results, bonding effectiveness of the self-adherent composite resin was also underscored to the self-etch adhesive system followed by the application of a flowable composite. 9 A microscopic morphological evaluation by Scanning Electron Microscope (SEM) observation on the nanoleakage of the inter-face between the composite material and primary teeth dentin showed that the nanoleakage score between self-adherent composite is comparable to the conventional composite.…”

Effect of mechanical alteration of enamel surface on shear bond strength of different bonding techniques

“…[ 4 ] However, various authors have reported relatively low bond strength values of SAC to dental hard tissues, thus necessitating an alteration in the bonding approach. [ 5 6 7 ] Restorative demands frequently present with clinical situations requiring bonding to intact, altered, or prepared enamel surfaces, which might bond differently with adhesive resins. Considering the limited information on bonding of SAC to enamel available in literature, this study was undertaken to evaluate the effect of mechanical alteration of enamel surface on shear bond strength of self-adhering composites utilizing different adhesive modalities.…”