Chemical and mechanical resistance of novel experimental hybrid coatings on dentin permeability

Abstract

This study aimed to evaluate the capacity of novel experimental hybrid coatings (HC) to reduce dentin permeability and to verify their resistance to erosive and abrasive challenges. Dentin disc specimens (1 mm thick) were treated with 0.5 M EDTA solution and randomly allocated into three experimental groups (n = 10): Control (Saliva); Concentrated Hybrid Coating (TEOS/GPTMS/Y‐APS); and Diluted Hybrid Coating (1:3 ratio with distilled water). Dentin permeability was assessed by hydraulic conductance in the following experimental time periods: post‐EDTA, post treatment, post erosion (5 min in 0.05 M citric acid solution, pH = 3.8), and post abrasion (toothbrushing for 3,900 cycles). Dentin permeability percent was calculated with respect the values of post‐EDTA for each experimental time. The morphology of the surface of extra dentin specimens was examined by scanning electron microscopy (SEM) in the same time periods (n = 3). Permeability data were analyzed by two‐way repeated measures ANOVA and Tukey tests (p < .05). Both HC presented significantly lower dentin permeability than control post treatment and post erosion (p < .05), without difference between them (p > .05). Post abrasion, there were no significant difference among groups (p > .05). Post treatment and post erosion, the HC seemed to flow into the tubules, occluding them, while the tubules in control remained opened. Post abrasion, the tubules appear to be occluded in all groups. In conclusion, the experimental hybrid coatings were capable of reducing dentin permeability after treatment. They were also able to resist to erosive and abrasive challenges, with the advantage of forming thinner and colorless films that can be potentially used to treat dentin hypersensitivity.

Erosive tooth wear inhibition by hybrid coatings with encapsulated fluoride and stannous ions

“…The hybrid solution was prepared as previously described [15,23], and contained a gamma-aminopropyltriethoxysilane (γ-APS), 3-glycidoxypropyltrimethoxysilane (GPTMS), and tetra ethylorthosilicate (TEOS). In this hybrid solution, functional alkoxides (γ-APS and GPTMS) modified the inorganic precursor (TEOS), forming a structure with organic-inorganic properties.…”

“…It has been hypothesized that the hybrid coatings would be capable of adhering to tooth surfaces after an alkaline treatment [ 15 ], since ions OH − are created on tooth surfaces at the calcium sites. The hybrid coatings are derived from hybrid solutions that contain silanol, which retains the Si–OH groups capable of interacting with the Ca–OH groups of tooth surfaces by means of low energy bonding, as hydrogen bonds.…”

Assessment of permeability of eroded dentin after the use of universal, self-etch, and conventional systems

“…The universal adhesive [Scotchbond Universal] used in normal dentin did not show any significant decrease in shear bond strength from the baseline under any degradation condition. However, in our study, the smear layer was completely removed and the dentinal tubules were fully opened in order to evaluate hydraulic conductance, according to the studies that evaluate dentinal permeability 5 .…”

“…Resin materials may thus be indicated both for protecting pulp against exposure to bacterial products between the period of dental preparation and cementation of the final indirect restoration (prehybridization) 3 , and for dentin hypersensitivity 2 in non-carious cervical lesions (NCCL). Hybrid coatings can be alternative for the treatment of clinical dentin hypersensitivity because they form a thin, colorless film on the dentin, 5 reducing the communication between the external environment and the pulp. However, the formation and maintenance of the hybrid layer are objects of investigation, 4,6 because the technique is challenging due to the complexity of the dentin tissue.…”

“…The presence in the oral cavity of acids of intrinsic or extrinsic origin 11 may result in dental erosion, affecting dental tissues (enamel/dentin) and degrading restorative materials 12 . Knowing that the dentinal fluid rate changes when hybrid coatings are applied after erosive challenges 5 , we became interested in learning about the behavior regarding hydraulic conductance of simplified universal systems. It is important to evaluate the intrinsic water permeability in adhesive systems because it is known to have a significant effect on the quality of bond strength and adhesive interface 13 .…”