Effect of phytic acid used as etchant on bond strength, smear layer, and pulpal cells

Abstract

This study aimed to evaluate the effect of phytic acid (IP6), used as etchant, on resin-dentin bond strength, smear layer removal, and the viability of pulpal cells. Flat dentin surfaces with smear layer were etched with 1% IP6 for 60, 30, or 15 s; in the control group 37% phosphoric acid (PA) was used. Dentin surfaces were rinsed, blot-dried, and bonded with an etch-and-rinse adhesive, followed by composite build-ups. The specimens were subjected to tensile testing after 24 h of water storage at 37°C, and failure modes were determined using scanning electron microscopy. The effectiveness of IP6 to remove the smear layer was observed using scanning electron microscopy. To evaluate the effect on pulpal cells, solutions of 0.1 and 0.01% IP6 and of 3.7 and 0.37% PA were prepared and rat pulpal cells were treated with these solutions for 6 and 24 h. Cell viability was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The results demonstrated that all application times of IP6 produced bond-strength values that were significantly higher than that of the control. Phytic acid effectively removed the smear layer and plugs, thus exposing the collagen network. Phytic acid had a minimal effect on pulpal cells, whereas PA resulted in a marked decrease in their viability.

Effect of phytic acid etchant on the structural stability of demineralized dentine and dentine bonding

“…29 It would be a great advantage that this etchant could also simultaneously stabilize the exposed collagen possibly through crosslinking effect. When a cross-linker is used separately after etchant, it is important to control the moisture to keep collagen in their expanded state during cross-linker application.…”

“…27 The knowledge about IP6 and its use in adhesive dentistry are limited. Recently, it was reported that IP6 has the potential to be an effective etchant, which demonstrated good dentine bonding and minimal cytotoxicity to pulpal-like cells, when compared with PA. 29 However, the mechanism behind the high bond strength of resin adhesive to IP6-etched dentine was not clearly understood. It was speculated that IP6 may act as a natural crosslinker to dentine collagen fibrils, which could mechanically strengthen them and prevent their collapse.…”

“…It was speculated that IP6 may act as a natural crosslinker to dentine collagen fibrils, which could mechanically strengthen them and prevent their collapse. 29 Therefore, the aim of this study was to evaluate the ability of IP6 to stabilize the morphology of demineralized dentine collagen. We studied its effect on the ultimate tensile strength (UTS) of demineralized dentine and the micromorphology of etched dentine surfaces, and examined dentine bond strength to IP6-etched dentine using wet-and dry-bonding techniques.…”

Effect of phytic acid on the setting times and tensile strengths of calcium silicate‐based cements

“…It has a unique chemical structure that comprises six phosphate groups linked to an inositol ring. Phytic acid increases the bond strength of restorative materials to dentine (11,12) and decreases the setting time of glass ionomer cement (13) with minimal adverse effects on cell viability. Phytic acid increases the bond strength of restorative materials to dentine (11,12) and decreases the setting time of glass ionomer cement (13) with minimal adverse effects on cell viability.…”

Effectiveness of three different irrigants - 17% ethylenediaminetetraacetic acid, Q-MIX, and phytic acid in smear layer removal: A comparative scanning electron microscope study

“…It has also got the cariostatic and antiplaque effect. [ 7 ] Phytic acid has got the ability to remove smear layer and was proved to be less cytotoxic and more biocompatible as compared to EDTA. [ 8 ]…”