Investigations of novel endodontic sealers and modifications of existing bioceramic sealers
OA Version
Citation
Abstract
The advent of modern bioactive sealers have introduced the ease of obturation with sealers that possess bioactive properties when used to obturate an endodontically treated canal. With increase use comes increased questions about the efficacy that these sealers have in obturating canals (1). From unpredictable setting time to questions about their ability to obturate and occlude dentinal tubules many questions and criticisms have arisen with their increased popularity. In light of these concerns this study sought to find if there alternative materials with bioactive properties that might adequately obturate an endodontically treated canal. The second part of this project sought to determine if the particle size of an existing bioceramic sealer and determine if the particles of the premixed bioceramic sealer could be reduced to size small enough to potentially obturate dentinal tubules (25).
Objective 1. : The first objective of this study was to determine if commercially available pulpal liners and crown and bridge cements could be used to seal endodontically treated canals.
Objective 2: the second objective of this project was to determine if reduction in particle size could improve the properties of an existing sealer.
Materials and Methods: One pulpal liner, Activa (Pulpadent), one crown and bridge cement Ceramir (Doxa), and EndoSequence BC sealer (Brasseler) were evaluated to determine if the repurposed materials could seal an endodontically treated canal with Endosequence as the control. The second part of this study modified a commercially available powder and liquid sealer, BioRoot (Septodont) BC sealer, to decrease its particle size and evaluated if this modification had any affect on its physical properties. 45 single-rooted teeth were decoronated, endodontically treated, and obturated using one of the commercially available products (n=3) Activa, Ceramir, Endosequence. The modified sealers were separated into groups by the time the powdered sealer was milled using a Speedmixer: 0 seconds (control), 40 seconds, 60 seconds, 120 seconds, and 240 seconds. Data was analyzed using a one-way ANOVA and all pairs comparison using a post-hoc Tukey-Kramer HSD test. Results: Of the repurposed materials Activa showed the most promising results with a setting time of 2.5 ± 0.9 hours as well as the best performance in terms of flow, film thickness, bond strength, and leakage resistance.
For the modified sealers the mechanical properties increased as the milling times were increased for all except shear bond, where bond strength peaked at 7.9 ± 6.9 MPa for 120 seconds of milling time. Conclusion: we were able to determine that Activa a pulpal liner demonstrates superior performance in terms of shear bond strength, dye-leakage prevention, setting time, film thickness, flow compared to EndoSequence bioceramic sealer. We were also able to successfully decrease the particle size of an existing bioceramic sealer and were able to show that this improved the setting time, film thickness, flow, and dye-leakage prevention, we were not able to show that it appreciably increased the bond strength of BioRoot bioceramic sealer to dentine in the root canal space.