Bioceramic sealer avoids shrinkage and excessive resorption

Dr. Rico D. Short discusses this promising option for endodontic treatment

Introduction

Two commonly used sealers present two different challenges. Resin-based sealers will shrink upon setting, while calcium hydroxide and zinc-oxide eugenol-based sealers can resorb over time. In contrast, bioceramic sealers expand slightly during setting (typically less than 0.2% of total volume) and, once set, will not resorb as readily as calcium hydroxide and zinc-oxide eugenol-based sealers.

Case discussion

A 41-year-old African American female referred to our office from her general dentist after having experienced pain on the lower right side of her mouth for several weeks. Clinical examination revealed a large carious lesion on tooth No. 30, and a periapical radiograph revealed a large periapical lesion on the mesial root (Figure 1). Because of the unusual anatomy of the mesial root, the patient was asked to approve a 3D CBCT to evaluate the root canal morphology and the periapical lesion in more detail. She declined the 3D CBCT scan. Pulp testing and periapical testing were then performed. A diagnosis of a necrotic pulp with acute apical periodontitis was confirmed. The patient agreed to have the treatment performed the same day.

The patient was anesthetized with two carpules of 2% Xylocaine 1:100,000 epi via an inferior alveolar block. Buccal and lingual infiltration was then performed with one carpule of Articaine 1:100,000 epinephrine. The tooth was isolated with a rubber dam, and the decay was removed in the clinical crown. Upon access and debridement, five canals (MB, MM, ML, DB, and DL) were located. Irrigation was performed using full-strength sodium hypochlorite with side-vented syringes while very carefully applying positive pressure. Working length was established with an apex locator. The five canals were cleaned and shaped using heat-treated nickel-titanium rotary files. A cone-fit radiograph was obtained to make sure proper length and fit were established after cleaning and shaping. A final rinse of 17% EDTA and 6% NaOCl was used in all five canals after which the canals were dried with paper points. Bioceramic sealer (NeoSEALER^® Flo; Avalon Biomed™ —Houston, Texas) was placed in all the canals with flexible dispensing tips (Flex Flo Tip™; Avalon Biomed). Care was taken to ensure the stopper was approximately 5 mm to 7 mm from the working length to minimize extrusion of the sealer. Finally, gutta-percha cones were placed inside the canals and seared at the pulpal floor.

The MB, MM, and ML canals had separate portals of exit (Figure 2), while the DB and DL canals joined at the apex. The presence of a third canal in the mesial root of mandibular first molars has been reported to have an incidence rate of 1% to 15%.¹ When confronted with this condition, it is very important to trough through the groove using a ball ultrasonic or high-speed bur to uncover this mid-mesial (MM) canal.

The patient reported that she was largely asymptomatic the day following the procedure. Her slight discomfort was managed with a combination of acetaminophen and ibuprofen. The patient will be recalled in 6 months to ensure that satisfactory osseous healing is taking place. She was referred back to her general dentist for a final restoration within 30 days.

Summary

The lack of shrinkage and the minimal resorption — as well as the non-resorbable hydrophilic nature, dimensional stability, biocompatibility, antibacterial property, bioactivity, and ease of delivery — make bioceramic sealers a promising option in endodontics. The gutta-percha cone used to drive the bioceramic sealer into cleaned isthmuses and irregular gaps serves as a soft core that allows for easier retreatment, as it is much less challenging to penetrate with hand or rotary files than is set cement.