Effect of smear layer deproteinization with chemo-mechanical caries removal agents on sealing performances of self-etch adhesives

J Dent. 2020 Mar:94:103300. doi: 10.1016/j.jdent.2020.103300. Epub 2020 Feb 15.

Abstract

Objectives: To evaluate the sealing performance of self-etch adhesives (SEA) after smear layer deproteinization with chemo-mechanical caries removal agents (CRA) to enamel and dentin cavity walls in comparison with 6% NaOCl smear layer deproteinizing.

Methods: Eighty extracted bovine incisors with tapered cylindrical cavities (2.5 mm upper diameter, 1.5 mm lower diameter, 2 mm depth) at the cemento-enamel junction were randomly divided into four pre-treatment groups; no treatment (control), Papacarie (papain enzyme-based CRA), Carisolv (NaOCl-based CRA), and 6% NaOCl. After pretreatment, G-Bond Plus (GBP, one-step SEA) or Clearfil SE Bond 2 (CSE, two-step SEA) was applied to the pre-treated cavity, and then filled with a flowable resin composite (Clearfil Majesty ES Flow). Gap formations at the enamel and dentin lateral walls, and on the dentin cavity floor were investigated using swept-source optical coherence tomography (SS-OCT) after 24-h water storage at 37 °C. Deproteinizing effects of the tested agents on smear layer-covered enamel and dentin were quantified by changes in the amide:phosphate ratio using ATR-FTIR analysis.

Results: Papacarie significantly reduced gap formation with both self-etch adhesives at all locations, compared to the control group (p < 0.05). In contrast, increased gap formation was observed with Carisolv and NaOCl. In most groups, CSE exhibited significantly lower gap formation than GBP (p < 0.05). ATR-FTIR revealed a significant decrease in the amide:phosphate ratio for all the deproteinizing agents (p < 0.05).

Conclusions: Chemo-mechanical CRAs could effectively remove the organic phase of enamel and dentin smear layer. The papain enzyme-based gel Papacarie could improve the sealing performance of the self-etch adhesives to both enamel and dentin.

Keywords: Chemo-mechanical; NaOCl-based gel; Papain enzyme-based gel; Sealing performance; Self-etch; Smear layer deproteinizing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adhesives
  • Animals
  • Cattle
  • Composite Resins
  • Dental Bonding*
  • Dental Cements
  • Dental Enamel
  • Dentin
  • Dentin-Bonding Agents
  • Materials Testing
  • Resin Cements
  • Smear Layer*

Substances

  • Adhesives
  • Composite Resins
  • Dental Cements
  • Dentin-Bonding Agents
  • Resin Cements