Effects of different irrigation protocols on dentin surfaces as revealed through quantitative 3D surface texture analysis

Abstract

The combination of ethylenediaminetetraacetic acid (EDTA) and sodium hypochlorite (NaOCl) has been advocated as an effective irrigation methodology to remove organic and inorganic matter in root canal therapy. Yet, it was suggested that both solutions might lead to structural changes of the dentinal wall surface, depending on the order of application which might affect sealer mechanical retention. This study aims to evaluate the effect of different irrigating protocols on dentin surface roughness using quantitative 3D surface texture analysis. Data stems from 150 human root dentin sections, divided into five groups, each prepared according to one of the following protocols: Negative control; 17% EDTA; 17% EDTA followed by 5.25% NaOCl; 5.25% NaOCl; and 5.25% NaOCl followed by 17% EDTA. Each dentin sample was examined for its three-dimensional surface texture using a high-resolution confocal disc-scanning measuring system. EDTA 17% and the combined EDTA 17% with NaOCl 5.25% showed considerably higher roughness properties compared to the control and to NaOCl 5.25% alone. However, the irrigation sequence did not affect the dentin roughness properties. Therefore, mechanical retention is probably not dependent upon the selection of irrigation protocol sequence.

Nanomechanical and Molecular Characterization of Aging in Dentinal Collagen

“…As the final step, PCA was carried out to understand the association among all studied variables. PCA is a statistical method that reduces a determined number of intercorrelated variables into dimensionless parameters called principal components (Jolliffe and Cadima 2016), and it has been recently used in dentistry to facilitate the interpretation of complex data sets (da Fontoura et al 2015; Elbahary et al 2020). The result of our PCA suggests that nanomechanical changes and MGO accumulation in the organic matrix of coronal dentin are important markers for tooth aging.…”

Nanomechanical and molecular characterization of aging in dentinal collagen

“…As the final step, a PCA analysis was carried out to further understand the association amongst all studied nanomechanical and molecular variables in both coronal and root dentin. PCA is a statistical method that reduces a determined number of intercorrelated variables into dimensionless parameters called principal components (Jolliffe and Cadima 2016), and has been recently used in dentistry to facilitate the interpretation of complex datasets (da Fontoura et al 2015; Elbahary et al 2020). Overall, when MGO levels and IT and PT collagen nanomechanical variables were analyzed together, samples showed clear clustering in two distinct groups representing <26 yo and >50 yo patients, distributed along the PC1 axis, with no clear influence of patient gender on these groupings ( Figure 4A ).…”

A critical analysis of research methods and experimental models to study tooth discolouration from endodontic materials

“…For orthograde root canal treatment, the ideal irrigation sequence, volume and application time remain disputed in the literature. Laboratory studies of endodontic discolouration have used various protocols for treating the root canal, typically with NaOCl irrigation, combined with ethylenediaminetetraacetic acid (EDTA), particularly at the end of instrumentation (Elbahary et al, 2020; Silveira et al, 2013). The use of different irrigation solutions cannot be expected to completely remove all traces of the smear layer in the apical third of the canal (Ahmetoglu et al, 2014; Silveira et al, 2013), but nevertheless it may influence the extent of penetration of endodontic materials from the root canal system into the dentinal tubules (Abbott et al, 1989).…”