Effect of Root Dentin Pretreatment on Micro-Push-Out Bond Strength of Fiber Posts to Root Canal Dentin: Cold Atmospheric Argon Plasma (CAAP) and Ethylenediaminetetraacetic Acid (EDTA)

Abstract

Purpose. Debonding from the root canal dentin is the most common failure mode of fiber posts. This study aimed to assess the effects of cold atmospheric argon plasma (CAAP) and ethylenediaminetetraacetic acid (EDTA) on micro-push-out bond strength of fiber posts to root canal dentin. Materials and Methods. Forty maxillary canine teeth were decoronated, underwent endodontic treatment, and were stored in an incubator for 7 days. After post space preparation, the teeth were randomly divided into four groups for different surface treatments: (I) saline, (II) 17% EDTA, (III) CAAP, and (IV) 17% EDTA + CAAP. Fiber posts (Whitepost no. 2, FGM) were cemented into the root canals using Panavia F2.0 resin cement, and 1 mm-thick sections were made at the coronal, middle, and apical thirds of the roots. The samples underwent micro-push-out bond strength test. The mode of failure was also determined under a stereomicroscope. Data were analyzed using three-way ANOVA and Tukey’s post hoc test (α = 0.05). The mode of failure data were analyzed using the chi-square test. Results. The mean micro-push-out bond strength of fiber posts was not significantly different in the four groups ( P > 0.05 ). However, the bond strength values in the coronal third were significantly higher than the corresponding values in the apical third ( P = 0.01 ). There was no significant difference in the modes of failure between the groups ( P > 0.05 ). Conclusion. Application of CAAP alone or in combination with 17% EDTA could not successfully increase the bond strength of fiber posts to root canal dentin.

Effect of pretreatment of root dentin surface with cold atmospheric plasma on improving the bond strength of fiber post and resin cement: In vitro study

“…Prado et al (2016) concluded that argon plasma treatment increases the penetration of resin-based sealer into the dentin in the coronal third. The type of plasma, duration of use, and distance of the plasma jet nozzle from the plasma-prepared surface affect the bond strength of the resin.The present study shows that the CAP irradiation for 60 s has a significant effect on bond strength, unlike the results of Mahounak et al, which had a plasma irradiation parameter of 180 s. The distance between the plasma nozzle and the tooth was 1 cm in the present study and was 2 cm in the Mahounak study as longer distances can result in energetic gas molecules deviating around the instrument and escaping, thereby diminishing the effectiveness of the treatment(Sadeghi Mahounak et al, 2021). This difference appears to reduce the penetration of the CAP into the root canal and also explains the rationale for decreasing the time of plasma usage in this study.…”

“…This study was conducted to evaluate the effect of root dentin surface pretreatment with CAP on improving the bond strength of fiber posts. In the present study, no surface treatments including etching or using sealants were performed because of the negative effect on bond strength (Lamichhane et al, 2014;Sadeghi Mahounak et al, 2021). Also, it has been stated that the weakest interface is between cement and root canal dentin, thus implying that surface treatment of fiber posts did not yield significant outcomes Abbreviations: AD, adhesive failure between dentin and cement (post is entirely covered with resin cement); AP, adhesive failure between cement and post (no cement remaining on the post); CD, cohesive failure in dentin; CP, cohesive failure in the post; EDTA, ethylenediaminetetraacetic acid; M1, mixed failure such that 0%-50% of the post surface was covered with cement; M2, mixed failure such that 50%-100% of the post surface was covered with cement.…”

“…The methodology used in this study was based on the findings of Sadeghi Mahounak et al ( 2021 ), who investigated the effect of root dentin pretreatment on the micro‐push‐out bond strength of fiber posts to root canal dentin. In their study, the authors used cold atmospheric argon plasma and EDTA as pretreatment agents and evaluated their effect on bond strength.…”

“…(a) SEM view of Mix 1 and (b) SEM view of penetration of resin into dentin tubules. Barreto et al (2016), but does not align with the studies ofGu et al (2009) andSadeghi Mahounak et al (2021). The different concentrations of EDTA and the different types of resin cements used can explain these differences.…”

“…The type of failure was classified as follows: AD, adhesive failure between dentin and cement (post is entirely covered with resin cement); AP, adhesive failure between cement and post (no cement remaining on the post); CD, cohesive failure in dentin; CP, cohesive failure in the post; M1, mixed failure such that 0%-50% of the post surface was covered with cement; M2, mixed failure such that 50%-100% of the post surface was covered with cement.Three dental sections were randomly selected from each group for scanning electron microscopy evaluation. The sections of isolated posts and failure areas were then evaluated using a computer and electron microscope (FEI Nova NanoSEM 450; magnification: ×100 and ×1000; SadeghiMahounak et al, 2021).…”