Atomic Force Microscopy of Removal of Dentin Smear Layers

Abstract

The regular periodontal practice of scaling and root planing produces a smear layer on the root surface that is detrimental to the readhesion of tissues during subsequent regeneration therapy. Although it has been demonstrated that gels containing the chelating agent ethylenediaminetetraacetic acid (EDTA) can assist in the removal of this contaminating layer, no quantitative method is yet available by which to evaluate the efficiency of the treatment. In this article, the power of atomic force microscopy (AFM) as a technique for monitoring and mapping the surfaces of dentinal roots is demonstrated. Roughness parameters of teeth that had been scaled and root planed were determined from AFM images acquired both before and after treatment with EDTA. The results confirmed that EDTA is an efficient cleaning agent and that dentinal samples free from a smear layer are significantly rougher than the same samples covered by a contaminating layer. AFM analysis is superior to alternative methods involving scanning electron microscopy because the same sample section can be analyzed many times, thus permitting it to be used as both the control and the treatment surface.

Influence of thicknesses of smear layer on the transdentinal cytotoxicity and bond strength of a resin-modified glass-ionomer cement

“…Despite the tendency for a decrease in the BS of Vitrebond to the smear-free dentin, no statistically significant difference was found among the four groups. Batista et al (22) demonstrated that the dentin treated with EDTA is much rougher than the smear-covered dentin. This fact could add to the interlocking of Vitrebond to smear-free dentin and might explain the statistically similar BS values obtained in the groups.…”

Clinical Evaluation of Demineralized Freeze‐Dried Bone Allograft With and Without Enamel Matrix Derivative for the Treatment of Periodontal Osseous Defects in Humans

“…Then, patients were assigned to one of two treatment groups by the selection of sealed envelopes containing a paper labeled “group 1” or “group 2.” In the event the patient had multiple defects, all defects were assigned the same treatment. The root surfaces were burnished with a cotton pellet soaked with 24% ethylene diamine tetraacetic acid gel ‖ for 2 minutes in an effort to remove the smear layer, 20 detoxify the root surface, expose collagen fibrils, 21 and, in the case of group 2, facilitate the precipitation of enamel matrix proteins onto the root surface 22,23 . Then the area was irrigated with 0.9% sterile saline.…”

Effect of the Insertion and Polymerization Technique in Composite Resin Restorations: Analysis of Marginal Gap by Atomic Force Microscopy

“…The AFM provides 3D highresolution images because it has a software with great mathematical accuracy for the mapping and characterization of surfaces~Silva Batista et al, 2007;Kakaboura et al, 2007! providing quantitative data on the length of marginal gaps.…”