Comparative Evaluation of the Penetration Depth into Dentinal Tubules of Three Endodontic Irrigants

Abstract

This study aimed to examine the penetration depth into dentinal tubules of some chelating agents. The 17% EDTA and two preparations containing surfactants (Smear Clear, Bioakt Endo) were tested. Surface tension and liquid viscosity were measured using a Dynamic Contact Angle Analyzer and a Haake rotational rheometer. To measure the penetration depth inside dentinal tubules, thirty maxillary central incisors were selected from a pool of extracted human permanent teeth and allocated to three experimental groups (10 samples each), as well as were mechanically shaped and cleansed with 5.25% NaOCl, followed by each of the chelators being labeled with 0.1 wt % Rhodamine B according to final irrigation protocol established. The samples were embedded in an epoxy resin, after which 200 μm thick transverse sections were obtained at 2, 5, and 8 mm from the apex with a saw microtome. The specimens were then observed using a confocal laser microscope (CLSM) and the penetration of the labeled solution was measured in every third of each sample. Statistical analysis was performed using ANOVA or Kruskal–Wallis tests according to the distribution of data, evaluated with the Shapiro–Wilk normality test. Viscosity and surface tension tests have shown that BioAKT Endo has the lowest values compared to EDTA and Smear Clear. The medium penetration depth did not significantly differ among the three irrigants, while it increased considerably from the apical to the coronal level in all groups. Additionally, the maximum penetration depth increased significantly from the apical to coronal level, while among groups, BioAKT Endo showed the highest values at the apical and middle level compared to the other irrigants. No significant differences were observed among the three groups in medium and maximum penetration depths when the entire root was considered. New irrigants containing surfactants show reduced surface tension and, in one case (BioAKT Endo), viscosity. The lowering of the surface tension allows for better penetration of liquids into dentinal tubules than EDTA alone, thus improving the cleaning of the root canal system.

The Effect of a Novel Silver-Citrate Root Canal Irrigation Solution (BioAkt), Ethylenediamine Tetraacetic Acid (EDTA), and Citric Acid on the Microhardness of Root Canal Dentin: A Comparative In Vitro Study

“…Actually, the purpose of selecting 40% citric acid in this study, which is four times more concentrated than 10%, is to detect the effect of a higher concentration on the microhardness of root canal dentin, while the reason for comparing the chelating solutions with EDTA is the well-researched and traditional use of the latter. BioAkt is an innovative endodontic irrigant consisting of citric acid (4.846%) and silver electrolytes (0.003%) in addition to detergents and water [7]. The chelating effect of BioAkt is due to the presence of citric acid [17], while the bactericidal characteristic is mainly contributed to silver ions; this unique composition specifies the dual function of BioAkt during endodontic treatment [18,19].…”

“…Furthermore, the stability, durability, and adhesive properties of root canal filling materials might be weakened and, thus, the success rate of endodontic therapy could be affected in return [3,5,6]. Recently, BioAkt, a new chemical formula composed of silver ions 0.003% in citric acid 4.846% is currently under research to evaluate its benefits and drawbacks as an antibacterial chelating agent during endodontic therapy [7]. Interestingly, the microhardness of root dentin has been the main concern of recent studies while assessing the action of up-to-date chelating agents.…”

Bromelain‐based endodontic irrigant: preparation, properties, and biocompatibility: An in‐vitro study

“…This finding suggests that BCE may provide deeper penetration into the dentin structure, thereby providing more efficient pre-treatment of the surface. Although there is limited data available on the efficacy of bromelain enzyme penetration into dentin structure, various publications have determined that lower surface tension improves the penetration of endodontic irrigants [21,22].…”

An in-vitro study on effects of laser activation on dye penetration in human root dentin

“…However, with traditional syringe irrigation the apical parts of root canal systems and deep dentin layers are often not reached, leading to persistent periradicular disease [9]. Conventional needle irrigation allows only NaOCl infiltration up to a depth of 250 µm into the tubules of root dentin [10] This might be due to chemical properties of irrigants such as the high surface tension as well as the limited streaming effects of the irrigation method [11,12].…”