Evaluation of The Sealing Ability of Gutta Percha with Bioroot RCS, MTA Fillapex and Sealapex - An SEM Study.

Aim of the Study: The objective of this in-vitro study was to assess the screening capabilities of three endodontic sealers, namely the BioRoot RCS, the MTA Fillapex, and Sealapex (a calcium hydroxide-based sealer), and the gutta-percha cone by using a scanning electron microscopy to the dentine walls. The results from the research are presented here.
Results: ZOE exhibited more gaps in the sealing materials evaluated with the least dental sealing performance, followed by the cervical third by the MTA Fillapex, the Sealapex, and the BioRoot RCS. The ZOE, followed by Sealapex, MTA Fillapex, and BioRoot RCS, exhibited inadequate dental wall sealing capacity in the middle of the third. The third apical ZOE exhibited more deficiencies in the formation of dental walls, followed by Sealapex, MTA Fillapex, and BioRoot RCS.
Conclusion: Under the constraints of the investigation, it can be stated that for the bioceramic sealer, a minimal gap was seen, with RCS of BioRoot superior to Fillapex of MTA. In the middle third, Sealapex was better adapted to the calcium hydroxide-based sealant than the MTA Fillapex sealer. MTA Filllapex had lower gap development than Sealapex in cervical or apical thirds. Copyright:

INTRODUCTION

Inadequate filling of the root canal during shuttering allows bacteria to reintroduce and grow in the root canal, producing periapical tissue irritations and threatening therapeutic results.[1] Although many materials have been used to shut off a root canal, the combination of gutta-percha cones with a root canal sealer is always the recommended approach.[2] As the root duct system is complex, pulp and inorganic waste remain at places that are not easy to access through the endodontic therapy process tools and irrigation solutions. These supply microorganisms that survive in the root canal, allowing them to grow and disseminate through the sealer-dentin contact to the periradicular zones.[3] One of the most prevalent reasons for endodontic treatment failure is related to the microleakage produced by an adaptation failure between the gutta percha and the sealant. To minimize gaps and voids on the sealing dentine interface, the adhesive between gutta-percha and dentinal walls is especially important for root canal sealers.[45]

Calcium hydroxide sealers have been demonstrated to have antibacterial properties as well as osteogenic and cementogenic potential. The justification for including calcium hydroxide in root canal sealers stems from observations of the action of cavity liners and bases containing calcium hydroxide, which are known for their antibacterial and tissue-regenerating properties.[67] Calcium hydroxide is formed when tricalcium silicate is hydrated with phosphates found in tissue fluids. The mineral infiltration zone refers to the interaction of these materials with the dentin.[8]

The purpose of this in-vitro scanning electron microscopy investigation is to see how well gutta-percha seals the root dentine by using a tricalcium silicate-based sealer (Bioroot RCS), a salicylate resin-based sealer (MTA Fillapex), and a calcium hydroxide-based sealer (Sealapex).

MATERIALS AND METHODS

For orthodontic reasons, a total of 40 noncarious, healthy adult mandibular premolar teeth with one root and root canal were chosen. The soft tissue and calculus were removed. A file number 10 K was pushed to the root channel until its tip was visible at the apical foramen, and the access through endo access bur was opened. Rotary canals were tested using ProTaper Universal rotary files in the following order: SX, S1, S2, F1, and F2 up to a speed of 300 rpm and a torque of 1.5 N.

For all four groups, each root was next sectioned in cross-sections by using a diamond disk on a slow-speed handpiece to get the dentin-root canal filling interface at the cervical, middle, and apical thirds of the root. As pointed out by Khalil et al.,[8] the specimens were exposed to continuous water chilling during sectioning to avoid frictional heat, which minimizes smearing of core obturating elements that tend to mask areas of sealer. After that, the sections were labeled appropriately. All sectioned specimens were washed in a 17% EDTA solution for 2 min and then blot dried before being mounted on aluminum stubs and examined using a scanning electron microscope.

RESULTS

The samples were divided into four groups:

Group 1: Gutta-percha with BioRoot RCS (n = 10).

Group 2: Gutta-percha with MTA Fillapex (n = 10).

Group 3: Gutta-percha with Sealapex (n = 10).

Group 4: Control group, Gutta-percha with ZOE (n = 10).

The gap creation of the four distinct sealers was assessed at the cervical, middle, and apical third levels in each experimental group. The sealer penetration was measured in micrometers from the sealer–gutta-percha interface to the dentinal wall in each sample group with n = 10 by using scanning electron microscope images at magnifications ranging from 50 × to 1000×.

At the cervical third level, Table 1 shows the mean and SD of gap formation at the gutta-percha–sealer interface to the dentinal wall in each group (BioRoot RCS, MTA Fillapex, Sealapex, and ZOE). ZOE has the greatest mean value [4.61] in the cervical third, followed by MTA Fillapex [1.612], Sealapex [1.593], and BioRoot RCS [0.747].

Table 1

Descriptive statistics of gap formation between groups

Post Hoc Tests - Multiple Comparisons - Tukey HSD
Dependent Variable	Mean Difference (I-J)	Std. Error	Sig.
CERVICAL
BioRoot RCS
MTA Fillapex	−0.864600	0.794	0.698#
Sealapex	−0.846200	0.794	0.712#
ZOE	−3.865600*	0.794	0.0005**
MTA Fillapex
Sealapex	0.018400	0.794	1.000#
ZOE	−3.001000*	0.794	0.003**
Sealapex
ZOE	−3.019400*	0.794	0.003**

# No Sig. at P>0.05 level, ** Highly Sig. at P<0.01 level

At the middle third level, Table 2 shows the mean and SD of gap formation at the gutta-percha–sealer interface to the dentinal wall in each group (BioRoot RCS, MTA Fillapex, Sealapex, and ZOE). The degree of gap formation between the sealer and root dentinal wall interface was very significant (P = 0.01) at the middle third.

Table 2

Descriptive statistics of gap formation between groups

Post Hoc Tests - Multiple Comparisons - Tukey HSD
Dependent Variable	Mean Difference (I-J)	Std. Error	Sig.
MIDDLE
BioRoot RCS
MTA Fillapex	−1.003300	0.810	0.607#
Sealapex	−1.411600	0.810	0.318#
ZOE	−4.398400*	0.810	0.0005**
MTA Fillapex
Sealapex	−0.408300	0.810	0.958#
ZOE	−3.395100*	0.810	0.001**
Sealapex
ZOE	−2.986800*	0.810	0.004**

# No Sig. at P>0.05 level, ** Highly Sig. at P<0.01 level

At the apical third level, Table 3 shows the mean and SD of gap creation at the gutta-percha–sealer interface to the dentinal wall in each group (BioRoot RCS, MTA Fillapex, Sealapex, and ZOE). The degree of gap formation between the sealer and root dentinal wall interface was very significant (P = 0.01) in the apical third.

Table 3

descriptive statistics of gap formation between groups

Post Hoc Tests - Multiple Comparisons - Tukey HSD
Dependent Variable	Mean Difference (I-J)	Std. Error	Sig.
APICAL
BioRoot RCS
MTA Fillapex	−1.671300	1.031	0.380#
Sealapex	−2.832100*	1.031	0.044*
ZOE	−7.553900*	1.031	0.0005**
MTA Fillapex
Sealapex	−1.160800	1.031	0.676#
ZOE	−5.882600*	1.031	0.0005**
Sealapex
ZOE	−4.721800*	1.031	0.0005 **

# No Sig., *Sig. at P<0.05 level and ** Highly Sig. at P<0.01 level”

At various degrees, all groups had both gap-free and gap-containing regions. MTA Fillapex and Sealapex, on the contrary, showed superior apical marginal adaptation to the dentinal wall than BioRoot RCS.

DISCUSSION

The fundamental purpose of root canal obturation is to create a three-dimensional fluid-tight seal in the root canal, preventing reinfection and preserving the health of the periapical tissues. According to Ingle, around 58% of endodontic failures can be related to incomplete root canal obturation.[9] Gutta-percha is the most widely used root canal obturating substance, having been in use for more than a century.[10] Because of its biocompatibility, non-toxicity, non-allergic nature, and ease of retrieval from the root canal in cases of retreatment, gutta-percha is the most preferred root canal obturating material.[11] Furthermore, the presence of a smear layer on the dentinal walls reduces dentin permeability and makes root canal sealer penetration into the dentinal tubules more difficult.[12] However, earlier research has established no link between the actual sealer penetration into dentinal tubules and the endodontic filling material's sealing ability.[13]

Various forms of evaluation of microleakage have been employed in the past for the evaluation of root canal sealers, including penetration of the color, electrical techniques, the process of filtering the fluid, tracing the radioisotope, and marginal adaptation by SEM.[13] The benefit of SEM is that submicron-level defects may be seen at appropriate SEM magnification compared to other microleakage assessment methods and the final evaluation can be done with microphotographs.[14]

A basic prerequisite of any root canal filling material is root canal sealer adhesion to root dentin at the dentin–sealer contact.[15] The marginal adaptation to root dentin at the cervical, middle, and apical thirds was evaluated using three root canal sealers: BioRoot RCS, MTA Fillapex, Sealapex, and ZOE (control group) sealers with gutta-percha. BioRoot RCS had greater marginal adaption at all three levels, as evidenced by decreased gap formation, compared to all of the experimental sealers, followed by MTA Fillapex, Sealapex, and ZOE. At the apical thirds of all sealer types, interfacial gaps were found to be larger than those seen at the coronal level. This finding was in line with the findings of prior investigations.[16]

Moreover, it is difficult to remove the smoothing layer from the apical third level, which might function as a physical barrier preventing the sealant from responding correctly to root duct dentine.[17]

The BioRoot RCS sealer was the best of the three groups examined in this study, with the least amount of gap creation at the dentin–sealer interface. It was recently hypothesized that hydraulic calcium silicate cements can be obturated using a single-cone cold obturation process.[18]

As a result, when the three distinct root canal sealers, namely BioRoot RCS, MTA Fillapex, and Sealapex, were compared in this study, it was discovered that BioRoot RCS had a better sealing ability. The MTA Fillapex and Sealapex groups adapted similarly, with MTA Fillapex outperforming the others. All of the evaluated sealers outperformed the ZOE sealer control group in terms of sealing ability.

CONCLUSION

Within the study's limits, the following points can be inferred:

Bioceramic sealers showed the least amount of gap formation, with BioRoot RCS outperforming MTA Fillapex.

In the mid-third, the sealer Sealapex based on calcium hydroxide exceeded the adaptation of the MTA Fillapex sealer. MTA Filllapex showed less gap formation in the cervical and apical thirds than Sealapex.

Compared with ZOE, in the cervical and middle thirds, all sealers examined showed significantly more adequateness and screening capacity than in the apical third.

Bioceramic sealers exhibited better apical third penetration.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.