Effect of Sodium Hypochlorite on Push-out Bond Strength of Four Calcium Silicate-based Endodontic Materials when used for repairing Perforations on Human Dentin: An in vitro Evaluation

Abstract

Aim: This study aimed to evaluate the push-out bond strength of NeoMTA Plus (NMTA), EndoSequence root repair material fast set putty (ERRMF), biodentine (BD), and ProRoot white mineral trioxide aggregate (PMTA) when used as perforation repair materials after exposure to 2.5% sodium hypochlorite (NaOCl) during the early setting phase. Materials and methods:Horizontal midroot sections were prepared from single-rooted human teeth. Sections (n = 144) were randomly divided into four groups: PMTA, BD, NMTA, and ERRMF. Materials were condensed and allowed to set for 10 minutes. The groups were further divided into two subgroups. The NaOCl group included specimens that were immersed in 2.5% NaOCl for 30 minutes, and the control group included specimens on which a wet cotton pellet was placed over the test material. After 48 hours, the highest force applied to the materials at the time of dislodgement was recorded. Slices were then examined under a digital microscope to evaluate the nature of the bond failure. The surfaces of two specimens from each subgroup were observed by scanning electron microscopy. Data were statistically analyzed with two-way and one-way analysis of variances, independent t-tests, and chi-square tests. The statistical significance was set at 0.05. Results:In NaOCl-treated groups, PMTA showed a significantly higher push-out bond strength than the other three materials (p = 0.00). In the control groups, the bond strength of BD was significantly higher than that of PMTA, ERRMF, and NMTA (p < 0.05). Compared with the control group, NaOCl treatment significantly increased the push-out bond strength of PMTA (p = 0.00) and ERRMF (p = 0.00) and significantly reduced the In ERRMF, the crystals were few in number. Sodium hypochlorite enhanced the crystallization of NMTA. Conclusion:The push-out bond strengths of PMTA and ERRMF were significantly increased after exposure to 2.5% NaOCl in the early setting phase, and those of BD and NMTA were significantly decreased. Clinical Significance:The results of the present study suggest that early exposure of NaOCl increase the push-out bond strength of PMTA and ERRMF. PMTA had the highest push-out values. Therefore, it would be a potentially useful perforation repair material for single visit endodontic treatment.

Morphological and chemical analysis of surface interaction of irrigant‐endosequence root repair material

“…SEM analysis confirmed the presence of unusual needle‐like shaped particles on the BC putty surface and undeveloped globular crystals with a lack of its original hexagonal shape on the BC paste surface when they immersed in NaOCl and CHX. Previous studies reported that NaOCl did not alter the crystalline structure of MTA or BC putty (Alsubait, 2017; Marciano et al, 2015). This feature may be attributed to the surface carbonation of both BC materials when it contacts with either NaOCl or CHX (El‐Turki et al, 2010).…”

“…Meanwhile, the alkalinity of NaOCl could induce surface oxidation that creates consumption and surface degradation. Alsubait (2017) confirmed that NaOCl enhanced the setting reaction, improved the physical properties, preserved the surface morphology, and did not interfere with cubic crystals formation, yet it can lower the amount of crystallization of BC putty.…”

“…Thirty round discs of each material (10 mm in diameter and 3 mm thick) were prepared. The discs were wrapped with gauze moistened with deionized water and incubated at 37°C and 100% humidity for 7 days or until completely set to mimic the clinical condition of human body temperature (Alsubait, 2017; Guneser, Akbulut, & Eldeniz, 2013). The discs were randomly divided into three subgroups and immersed in either 5.25% NaOCl, 2% CHX (experimental subgroups), or saline (control subgroup) for 10 min ( n = 10).…”

“…Previous studies evaluated the influence of root canal irrigants on the mechanical properties of BC‐RRM. The use of 2.5% NaOCl significantly increased push‐out bond strength (Alsubait, 2017) and microhardness (Chu, Chia, Qui, Moule, & Ha, 2020) of BC‐RRM. Meanwhile, the putty form of BC‐RRM recorded a significantly lower value of push‐out bond strength when immersed in either 5.25% NaOCl or 2% CHX compared to the control group (Alamoudi & Abu Zeid, 2019).…”

“…During treatment, the material should be placed immediately after the accident to seal off the perforation and prevent microbial leakage to the surrounding periodontal tissues, while, the root canal cleaning does not sufficiently complete (Tsesis & Fuss, 2006). After completion of chemomechanical preparation of the root canal, further irrigation is required to remove residual microorganisms and dentin debris that could affect the repair materials (Alsubait, 2017).…”