Mechanism of action of Bioactive Endodontic Materials

Abstract

A continuous search for bioactive materials capable of supporting the replacement of damaged pulp tissue, with effective sealing potential and biocompatibility, has represented the attention of studies over the last decades. This study involves a narrative review of the literature developed by searching representative research in PUBMED/MEDLINE and searches in textbooks associated with the mechanism of action of bioactive materials (calcium hydroxide, mineral trioxide aggregate (MTA), and calcium silicate cements). The reflective analysis of the particularities of the chemical elements of these materials, considering the tissue and antibacterial mechanism of action, allows a better understanding of the characteristics and similarities in their tissue responses. Calcium hydroxide paste remains the antibacterial substance of choice as intracanal dressing for the treatment of root canal system infections. Calcium silicate cements, including MTA, show a favorable biological response with the stimulation of mineralized tissue deposition in sealed areas when in contact with connective tissue. This is due to the similarity between the chemical elements, especially ionic dissociation, the potential stimulation of enzymes in tissues, and the contribution towards an alkaline environment due to the pH of these materials. The behavior of bioactive materials, especially MTA and the new calcium silicate cements in the biological sealing activity, has been shown to be effective. Contemporary endodontics has access to bioactive materials with similar properties, which can stimulate a biological seal in lateral and furcation root perforations, root-end fillings and root fillings, pulp capping, pulpotomy, apexification, and regenerative endodontic procedures, in addition to other clinical conditions.

Evaluation of cytotoxicity and adaptability of a novel bioceramic root canal sealer: An in vitro and scanning electron microscope study

“…[ 19 ] Raising the pH level can cause damage to the cytoplasmic membrane, DNA, and proteins, which can lead to the death of bacteria as well as the host cells. [ 20 ] Results of the current study are consistent with Loushine et al . who found that at the 24-h period, the cytotoxicity of Endosequence BC sealer was greater compared to AH Plus and justified that by the more extended final setting time of the bioceramic sealer that could lead to the components leaching over a prolonged period and negatively influence cell viability.…”

The effects of heating on the physicochemical properties of tricalcium silicate root canal sealers

“…Heating did not alter the alkalinity of all the tested sealers which corroborates with previous publications 3 , 4 , 6 . The high pH values of the tricalcium silicate sealers are related to the formation of Portlandite (calcium hydroxide) as a hydration product, which results in calcium and hydroxyl ions released 6 , 23 .…”

Marginal Adaptation and Porosity of a Novel MTA Brand Applied as Root-End Filling Material: A Micro-CT Study

“…The cavity volume (Vc) and the root-end filling material volume (Vm) were measured in mm 3 . Then the following parameters were calculated: (1) the volume of the interfacial gaps and voids present in the material-to-dentin wall interface, defined as open porosity volume for brevity (OPV); and (2) the volume of micropores within the material, defined as closed porosity volume (CPV).…”

“…The quantities of both the internal and interfacial porosity fractions were measured separately and as the total amount (TPV). They were calculated as absolute values in mm 3 and relative values in percentages.…”

“…[1,2]. Due to their unique physicochemical and biological properties, CSCs have currently been considered an excellent root-end filling material [2][3][4][5].…”