The Effect of Different Final Irrigation Regimens on the Dentinal Tubule Penetration of Three Different Root Canal Sealers: A Confocal Laser Scanning Microscopy Study In Vitro

Abstract

This study evaluated the effects of different final irrigation regimens on the dentin tubule penetration of three different root canal sealers using confocal laser scanning microscopy (CLSM). A total of 160 single-rooted extracted mandibular premolar teeth were divided into five groups ( n = 32 each) according to the solution used in the final rinse protocol, as follows: 17% ethylenediaminetetraacetic acid (EDTA) (group 1), 17% EDTA and 2% chlorhexidine gluconate (CHX) (group 2), 7% maleic acid (MA) (group 3), 7% MA and 2% CHX (group 4), and 5.25% NaOCl (group 5). Two roots from each group were examined under scanning electron microscopy (SEM) to visualize smear layer removal. Experimental groups were then split randomly into three subgroups ( n = 10 ) and obturated using a cold lateral condensation technique with 0.1% rhodamine B-labelled sealers [either AH Plus (group A), EndoREZ (group E), or Tech BioSealer Endo (group T)] and gutta-percha. Specimens were sectioned and observed by CLSM to evaluate the percentage and maximum depth of sealer penetration at the apical, middle, and coronal levels. Statistical comparison was performed on grouped (apical, middle, and coronal segments) and ungrouped data using two-way ANOVA with Bonferroni post hoc test ( p < 0.01 ). AH Plus showed the greatest tubule penetration while Tech BioSealer Endo showed the least. Resin-based sealers displayed deeper and more consistent penetration. CHX irrigation positively influenced sealer tubule penetration.

The Effect of Four Different Irrigating Solutions on the Depth of Penetration of Various Sealers into Dentinal Tubules

“…According to the results of this study, we found that CHX irrigation showed the highest percentage of penetration in coronal sections as compared to others irrigants in both types of sealers (MTA fillapex -AH plus). Recently Zandi et al have shown that CHX can be used as a main irrigant, with similar success rates to those obtained with NaoCL (23) . Since, Rhodamine B dye was added to CHX to evaluate their penetration depth into dentinal tubules under confocal laser microscope, by mixing CHX with Rhodamine B the surface tension of CHX could be altered.…”

Evaluation of push-out bond strength, dentinal tubule penetration and adhesive pattern of bio-ceramic and epoxy resin-based root canal sealers

“…However, CLSM was used in the current study to establish the depth of dentinal tubule penetration as it offers multiple advantages over the other methods. It can provide necessary information about sealer penetration within the root canal system along the dentinal tubule and allows the visualisation of depth and control of the depth by reducing or incising the background information from the focal plane, and is capable of assembling multiple optical sections despite of a thick section of specimen [ 34 , 35 ]. To evaluate dentinal tubule penetration, samples need to contain fluorescent dye.…”

Direct and indirect eluates from bulk fill resin-based-composites

“…Briefly, in the first case, it is conceivable that dust particles from drilling, inorganic filler particles or the insertion of the adhesive system can close dentinal tubules. Moreover, the smear layer cannot be completely removed and depends on the reagents and techniques used [32,33]. Occlusion can also occur via large molecules blocking tubules and/or absorption processes on the collagen fibers within the dentinal tubules.…”