An In vitro Comparison of Pushout Bond Strength of Resilon with MetaSEAL and AH Plus Sealers

Effect of Distinctive Moisture Conditions on Push-out Bond Strength of Three Root Canal Sealers-An In-Vitro Study

Objective:

Endodontic sealer should adhere to both dentin and the core filling material but the moisture conditions of the canals affect the adhesive properties of the sealer. An ideal sealer with perfect moisture conditions will lead to greater strength of the restored tooth, which may provide greater resistance to tooth fracture and clinical longevity of an endodontically treated tooth. The aim of this study was to evaluate the effect of moisture conditions on the push-out bond strength of three root canal sealers: AH Plus^® (Dentsply-Tulsa Dental, Tulsa, OK), Epiphany (Pentron Clinical Technologies, Wallingford, CT), and GuttaFlow (Coltene/Whaledent, Altstatten, Switzerland).

Materials and Methods:

A total of 120 single-rooted, non-carious teeth were collected for the study and were stored in normal saline. The root canals were prepared using step-back technique. Teeth were divided into four groups based on type of drying procedure used and further subdivided into three subgroups based on the type of sealer used. The samples were cut horizontally to produce slices and then tested for push-out bond strength using Universal Testing Machine (Servo Series 50 kN; P S I Sales Private Limited, New Delhi, India). The specimens were examined for mode of fracture under magnification and the results were analyzed statistically.

Results:

Distinctive moisture conditions for all sealers were observed and the highest strength of AH Plus^® was evaluated under moist condition, Epiphany under dry condition, and GuttaFlow under normal condition, respectively.

Conclusion:

Distinctive moisture conditions affect the push-out bond strength of the sealers.

Novel bioactive root canal sealer with antibiofilm and remineralization properties

OBJECTIVES

(1) To develop a novel bioactive root canal sealer with antibiofilm and remineralization properties using dimethylaminohexadecyl methacrylate (DMAHDM) and nanoparticles of amorphous calcium phosphate (NACP); (2) investigate the effects on E. faecalis biofilm inhibition, sealer flow and sealing ability, compared with an epoxy-resin-based sealer AH Plus; and (3) investigate the calcium (Ca) and phosphate (P) ion release from the sealers.

METHODS

A series of dual-cure endodontic sealers were formulated with DMAHDM and NACP at 5% and 20% by mass, respectively. Flow properties and sealing ability of the sealers were measured. Colony-forming units (CFU), live/dead assay, and polysaccharide production of biofilms on sealers were determined. Ca and P ion releases from the sealers were measured.

RESULTS

The new sealer containing 20% NACP and 5% DMAHDM yielded a paste flow of (28.99 ± 0.69) mm, within the range of ISO recommendations. The sealing properties of the sealer with 5% DMAHDM and 20% NACP were similar to a commercial control (p > 0.05). The sealer with DMAHDM decreased E. faecalis biofilm CFU by more than 4 orders of magnitude, compared to AH plus and experimental controls. The sealer with 20% NACP and 5% DMAHDM had relatively high levels of Ca and P ion release necessary for remineralization.

CONCLUSIONS

A new bioactive endodontic sealer was developed with strong antibiofilm activity against E. faecalis biofilms and high levels of Ca and P ion release for remineralization, without compromising the paste flow and sealing properties.

CLINICAL SIGNIFICANCE

The bioactive antibacterial and remineralizing root canal sealer is promising to inhibit E. faecalis biofilms to prevent endodontic treatment failure and secondary endodontic infections, while releasing high levels of Ca and P ions that could remineralize and strengthen the tooth structures and potentially prevent future root fractures and teeth extractions.