It seems that increasing numbers of today’s dental materials are described as being “bioactive,” in that they interact with the body. But with respect to dental materials, the term “bioactive” is still up for debate. For instance, while some in the dental community view glass ionomers as bioactive, others do not.
Materials such as glass ionomers and giomers do, in a sense, interact with the body by initiating ongoing fluoride ion exchange. Yet, numerous experts in the field insist that to be classified as bioactive, a material must precipitate hydroxyapatite in the presence of moisture, and release not only fluoride but also calcium and phosphate — natural components of tooth enamel.1
Material Wealth
Long used in orthopedic applications, bioceramics now represent a fairly large category of today’s dental materials. Under this umbrella are alumina and zirconia, both crystalline-based ceramics, and glass ceramics such as lithium disilicate. These materials have become popular for use as indirect restorative prosthetics. Although they are biocompatible, they are inert in the body.2
Other members of the bioceramic category are used as cements and sealants. They include bioactive glass, hydroxyapatite, calcium phosphates, bioaggregates and some calcium-silicates.2 When fully set, these materials do exhibit bioactivity by releasing calcium hydroxide upon contact with oral fluids. When this interacts with phosphates in tissue fluids it forms hydroxyapatite, fostering remineralization of tooth structure — and protecting it. 3–7
Applications
Bioceramics may be used in various aspects of dentistry. For instance, they’ve become popular as luting cements due to their bioactive properties. And such materials are a boon to the concept of minimally invasive dentistry. Because caries is a bacterial disease, using a remineralizing material to fill early carious lesions makes more sense than simply drilling a bigger hole and filling it with inert material.
Endodontists are taking advantage of the unique properties of bioactive cements and sealers for treatments such as pulp capping, pulpotomy, perforation repair, root-end filling, and even obturation.1,6-8
As gutta percha, the primary obturation material for root canal treatments, is inert and nonadhesive, the additional use of bioceramic sealers is tremendously beneficial. There is evidence that these sealers actually strengthen root canals and increase fracture resistance. They are also said to set at a high pH, which discourages bacterial proliferation.4,7
Bioceramic sealers used in endodontics include mineral trioxide aggregate (MTA) and other similar, but proprietary, branded formulations offering easy use, high flowability to penetrate into canal irregularities, hydrophilicity and zero shrinkage. In fact these materials are actually said to expand slightly on setting, helping to ensure marginal integrity.4
Best Practices
Savvy clinicians know that even when working with hydrophilic materials, isolation can be key. Especially in the case of endodontic work, it is paramount in minimizing contamination. By utilizing systems such as Isolite 3, Isodry or Isovac, practitioners are giving themselves and their patients the best shot at successful treatment outcomes. All systems are centered around a flexible mouthpiece that’s not only comfortable for the patient, but a snap to place and remove. Offering continuous suction and retraction, these kinds of systems enhance treatment, safety and operatory efficiency, while the Isolite 3 adds shadowless illumination.
Bioactive materials such as bioceramics are proving to be important players in dental applications. Not only do they offer countless benefits, but they are reportedly not technique sensitive.4 Used in combination with an easily placed isolation system, that adds up to a major coup for busy practitioners.
REFERENCES
- Stone R. Material wealth. Mentor. 2016;7(6):32–37.
- Chang JWW, Praisarnti C, Neelakantan P. Increasing use of bioceramics in endodontics: a narrative review. Available at: https://www.oralhealthgroup.com/features/increasing-use-of-bioceramics-in-endodontics-a-narrative-review/. Accessed January 2, 2019.
- Al-eesa NA, Johal A, Hill RG, Wong FS. Fluoride containing bioactive glass composite for orthodontic adhesives — apatite formation properties. Dent Mater. 2018;34:1127–1133.
- Stone R. Bridging the canal. Mentor. 2018;9(1):22–28.
- Richardson IG. The calcium silicate hydrates. Cement and Concrete Research. 2008;38:137–158.
- Haapasalo M, Parhar M, Huang X, Wei X, Lin J, Shen Y. Clinical use of bioceramic materials. Endo Topics. 2015;32:97–117.
- Wang Z. Bioceramic materials in endodontics. Endo Topics. 2015;32:3–30.
- Trope M, Bunes A, Debelian G. Root filling materials and techniques: bioceramics a new hope? Endo Topics. 2015;32:86–96.