Bibliographic review
Physical properties of clinical utility of the new endodontics sealant cements based on silicates. Bibliographic review
Introduction: The obturation of the duct system plays a key role in the success of endodontic treatment. In an attempt to improve the properties of sealants cements, silicate-based sealants have recently been introduced to the market. Therefore, when carrying out the sealing of the duct system, it is useful to know the physical properties that the cement sealants present.
Objective: The objective of this work was to review the literature of the useful clinical physical properties that the new silicatebased cements present, and to compare them with the physical properties of the conventional epoxy resin-based cements.
Material and method: After establishing the adapted research question, a literature review was carried out in two databases (Medline via Pubmed and Wiley Library via Chrocane Library) combining MeSH terms (Medical Subject Headings) and free terms.
In addition, a manual electronic search was carried out. The useful clinical physical properties selected were discoloration, sealing capacity, radiodensity, setting time and solubility.
Results: 224 potential studies were obtained. Finally, applying the inclusion and exclusion criteria, 22 studies were included in the review. The different studies compared the different physical properties of silicate-based cements, comparing them with resin-based cements.
Conclusions: Between silicate-based cements and resin cements, no differences in tooth discoloration were observed.
Nor differences were observed in sealing in most of the studies consulted. All the cements analysed presented radiodensity values within the recommended standards. Both the setting time and the solution depended on the type of cement evaluated. Some of the silicate-based cements showed higher solubility compared to resin-based cements.
To achieve success in endodontic treatment, it is necessary to obtain a complete obturation, after cleaning and conformation of the duct1 system. The materials commonly used in obturation are guttapercha and 2 sealants. Sealing cements are substances capable of penetrating between the obturation material and root canals3. There are different types available on the market, however, despite gathering many of the features described by Grossman, they do not manage to gather all4. They can be classified according to their main components5 in: zinc oxide–eugenol cement, calcium hydroxide cements, glass ionomer cements, silicone cements, resin cements or ceramic6 cements.
At present, cements composed of resins are the most used, being considered the epoxy resin cement AH PlusTM, the gold standard3,7. However, this cement presents a number of limitations such as a possible cytotoxicity, mutagenicity and inflammatory response8.
In addition, another limitation of this cement is the absence of bioactive properties9. Therefore, new types of sealants called bioceramic10 have recently been introduced to the market. These cements are based on the biological characteristics of MTA11 and include in their composition calcium silicates, calcium phosphates, calcium hydroxide and zirconium oxide as radiopacifier12. Therefore, the development of bioceramic cements has been based on obtaining a good biocompatibility. However, these cements must also have adequate physical properties4.
One of the physical properties that has gained importance in recent years is aesthetics7. The aesthetic result of the treatment of the opening is important, especially in the previous region13, since, although the access cavity is adequately prepared and cleaned with alcohol, there is a possibility that some cement sealant14 remains. On the other hand, the evaluation of the sealing capacity of new cement sealants is another property that has been considered an important parameter to consider5. The dimensional changes of the canal system, as well as the lack of adhesion of the gutta-percha, condition the achievement of complete sealing. Therefore, the adaptation of the sealing cement is a factor that influences the microfiltration and reinfection of the canal15 system. Another property considered essential is radiodensity, since it allows clinicians to distinguish between the materials used and adjacent anatomical structures16, as well as to assess the quality of the canal filler17. Another physical property that the clinician must take into account is the setting time. A slow or incomplete setting time may result in increased tissue irritation18, while a very short setting time may decrease the working time complicating and interfering with the obturation process19. Therefore, the setting time should be long enough to allow easy handling, especially in those sealing techniques that require more time20. Another property that has special relevance when evaluating sealants cements is the solubility21. Dissolution of the sealing cement could interfere with the quality of the canal treatment and trigger an inflammatory response of periapical tissues21,22. In addition, a vacuum could occur between the sealing material and the canal, increasing filtration over time21. Therefore, sealants should have a low solubility rate22.
Since there are different resin-based cements available on the market, it is important to know their physical properties. The objective of this literature review study was to analyse the scientific evidence of different physical properties of clinical applicability of different silicate-based sealants cements such as tooth discoloration, sealing capacity, radiodensity, setting time and solubility, and compare them with conventional resin-based cements.
