Lack of correlation between sealer penetration into dentinal tubules and sealability in nonbonded root fillings

Abstract

De‐Deus G, Brandão MC, Leal F, Reis C, Souza EM, Luna AS, Paciornik S, Fidel S. Lack of correlation between sealer penetration into dentinal tubules and sealability in nonbonded root fillings. International Endodontic Journal, 45, 642–651, 2012. Abstract Aim To determine the correlation between leakage and sealer penetration into dentinal tubule. Methodology The root canal of 60 mandibular central incisor teeth were prepared and filled under standardized conditions. Teeth were placed into a device to assess glucose penetration using 15 psi pressure application. After 1 h, glucose concentrations in the lower chamber were measured using an enzymatic reaction. Each specimen was then sectioned horizontally at 3, 6 and 8 mm from the apex, and a standard metallographic preparation was performed. The coronally facing surface of each slice was examined in a high‐resolution stereomicroscope and under Confocal Laser Scanning Microscope. For each slice, the external outline of the root canal, the internal circumference of the root canal walls and the areas along the canal walls where the sealer had penetrated into the dentinal tubules (sealer tags) were outlined and measured. Afterwards, the percentage of the sealer penetration in each section was calculated. The Spearman correlation test was used to verify the correlation between the variables studied (glucose leakage and sealer penetration into dentinal tubules). Results The means and standard deviations of glucose leakage were 0.744 g L−1 (±0.5), and the percentage of the dentinal tubule sealer penetration varied between teeth from 5.6% to 42.21%, with an average of 13.7 ± 17.2%. The Spearman correlation test revealed no significant correlation between the two factors analysed (P = 0.082). The r2 value was equal to 0.12. Conclusions There was no significant correlation between sealability sealer penetration into dentinal tubles. The lack of correlation reported is of relevance as sealer penetration into dentinal tubules has been used as an advantageous property during the launch of new root filling materials and techniques.

Epoxy Resin-Based Root Canal Sealer Penetration into Dentin Tubules Does not Improve Root Filling Dislodgement Resistance

“…However, very recently, no correlation has been found between the penetration ability of a sealer into the dentin tubules and the sealability in non-bonded root fillings (10). The present results point out that the force required to dislodge a root canal filling is not dependent on the tubular dentin sealer penetration.…”

“…In the present study, the results for sealer penetration into dentin varied from 1.45% to 45.98%, which can be regarded as a consequence of uncontrolled dentin permeability ( Figure 1). Enhanced sclerotic dentin in the apical third, especially in older adults, may negatively impact sealer penetration into the dentin tissue (10,18,20). Even though dentin permeability was not controlled in this study and could have been responsible for the large variation in the results, the reliability of the correlation was not affected since the data regarding the variability of the force required to dislodge a root canal filling should agree with the variability in the sealer penetration.…”

“…Therefore, it should be questioned if i) sealer penetration into dentin tubules, ii) the force required to dislodge a root canal filling, and iii) microleakage are indeed desirable experimental outcome variables to rank the root filling materials and techniques. Considering the present results plus the findings obtained by De-Deus et al (10), the use of sealer penetration into dentin can lead to experimental ranking of the root filling materials and techniques.…”

“…The microscopic procedures to determine the percentage of sealer penetration into the dentin tubules followed the same routine in a previously published article (10). The coronal facing surface of each slice was microscopically examined after performing a standard metallographic preparation.…”

Influence of Root Canal Filling Techniques on Sealer Penetration and Bond Strength to Dentin

“…Different root canal filling techniques have been proposed (5,6) as attempt to fill the root canal in three dimensions (7) and reduce marginal apical and coronal infiltration (8). Among these techniques, lateral condensation, which is the most commonly used technique, is worth mentioning (7) and warm vertical compaction, which promotes plastification of gutta-percha to provide homogeneity of the obturating mass and better adaptation to the root canal walls (9).…”