| trends & applications Endodontic bioceramics are not sensitive to moisture and blood contamination and therefore are not tech- nique-sensitive.5–9 They are dimensionally stable and expand slightly.10 When set, they are hard, allowing full compaction of a final restoration, and they are insoluble over time, ensuring a superior long-term seal. When set- ting, the pH is above 12 owing to the hydration reaction, which first forms calcium hydroxide and then dissoci- ates into calcium (Ca2+) and hydroxyl ions (Figs. 1a & b).11 Therefore, when unset, the material has antibacterial properties. When fully set, it is biocompatible and even bioactive. When bioceramic materials come into contact with tissue fluid, they release calcium hydroxide, which can interact with phosphates in the tissue fluid to form hydroxyapatite (Fig. 1c). This property may explain some of the tissue-inductive properties of the material. For the reasons above, these materials are recommended for pulp capping, pulpotomy, perforation repair, root end fill- ing, obturation of immature teeth with open apices, and sealing of root canal fillings of mature teeth with closed apices. Available bioceramic materials in endodontics There are several bioceramic materials and brands available in the dental market today. The most popular type used in endodontics are listed below: Mineral trioxide aggregate Few clinicians realise that original MTA is a classic bio- ceramic material with some heavy metals added. MTA is one of the most extensively researched materials in the dental field.12, 13 It has the properties of all bioceram- ics; that is, it has a high pH when unset, is biocompat- ible and bioactive when set, and provides an excellent seal over time. It has some disadvantages, however. It requires mixing, resulting in considerable waste, is not easy to manipulate, and is difficult to remove. Clini- cally, both gray and white MTA stain dentine, presumably owing to the heavy-metal content of the material or the inclusion of blood pigment while setting.14, 15 Finally, MTA is difficult to apply in narrow canals, making the mate- rial poorly suited for use as a sealer together with gutta- percha. Efforts have been made to overcome these short- comings with new compositions of MTA or with additives. However, these formulations affect MTA’s physical and mechanical characteristics. Biodentine Biodentine (Septodont) is considered a second-gen- eration bioceramic material. It has properties similar to those of MTA and thus can be used for all the applications described above for MTA.1, 16 Its advantages over MTA are that it sets in a shorter pe- riod (approximately 10 to 12 minutes) and it has a com- pressive strength similar to that of dentine. A major dis- advantage is that it is triturated for 30 seconds in a preset quantity (capsule), making waste inevitable, since in the vast majority of endodontic cases, only a small amount is required. Endodontic pre-mixed bioceramics In 2007, a Canadian research and product develop- ment company (Innovative Bio-Ceramix) developed a pre-mixed, ready-to-use calcium silicate-based material, iRoot SP injectable root canal sealer.1 Since 2008, these endodontic pre-mixed bioceramic products have been available in North America from Brasseler US as EndoSequence BC Sealer, Endo- Sequence BC RRM (Root Repair Material, a syringable paste), and EndoSequence BC RRM Fast Set Putty (Fig. 2). Recently, these materials have also been marketed as TotalFill BC Sealer, TotalFill BC RRM Paste and TotalFill BC RRM Putty/Fast Set Putty (Fig. 3) by FKG Dentaire.16 All three forms of bioceramic are similar in chemical com- position (calcium silicates, zirconia, tantalum pentoxide, Fig. 8a Fig. 8b Fig. 8c Figs. 8a–c: Pre-op radiograph of a case demonstrating apical periodontitis (a). Post-op radiograph at four weeks (b). One-year follow-up with complete healing (c). (Images courtesy of Dr Gilberto Debelian) 30 roots 2 2019