Effect of Yellow Propolis on Biocompatibility of Cements: Morphological and Immunohistochemistry Analysis

Analysis of Tissue Repair of a New Cement Based on Calcium and Strontium Aluminates: A Triple-Blinded, Randomized, Controlled Trial in an Animal Model

OBJECTIVE

 The focus of this triple-blind randomized study was to evaluate the biocompatibility of a new root canal filling sealer (RCFS) based on tristrontium aluminate and dodecacalcium hepta-aluminate in living tissue.

MATERIAL AND METHODS

 Forty-five Wistar rats (Rattus norvegicus) were divided into three groups: control (polyethylene), sealer (Bio-C Sealer, Londrina, PR, Brazil), and experimental (tristrontium aluminate and dodecacalcium hepta-aluminate). The tissues were analyzed under an optical microscope to assess different cellular events at different time intervals (7, 15, and 30 days).

STATISTICAL ANALYSIS

 Data were analyzed using the Kruskal-Wallis and Dunn (p < 0.05) tests.

RESULTS

 In the initial period, a moderate inflammatory infiltrate was observed, similar between the endodontic cements groups (p = 0.725). The intensity of the infiltrate decreased with time, with no significant difference among the groups (p > 0.05). The number of young fibroblasts was elevated in all groups evaluated at 7 days. The experimental group showed the highest number of cells at all time intervals, but the difference with the sealer group at 7 (p = 0.001) and 15 days (p = 0.002) and the control group at 30 days was not significant (p = 0.001). Regarding tissue repair events, the amount of collagen fibers increased over the experimental intervals, with no significant difference between the sealer and control groups (p > 0.05).

CONCLUSION

 The experimental RCFS based on calcium and strontium aluminates proved to be biocompatible for use in close contact with periapical tissue, inducing a low inflammatory reaction and favoring rapid tissue repair.

Incorporation of Nanomaterials in Glass Ionomer Cements-Recent Developments and Future Perspectives: A Narrative Review

Glass ionomer cements (GICs), restorative materials with commercial availability spanning over five decades, are widely applied due to their advantages (including bio-compatibility, fluoride release, or excellent bonding properties). However, GICs have shortcomings. Among the disadvantages limiting the application of GICs, the poor mechanical properties are the most significant. In order to enhance the mechanical or antimicrobial properties of these materials, the addition of nanomaterials represents a viable approach. The present paper aims to review the literature on the application of different types of nanomaterials for the enhancement of GICs' mechanical and antimicrobial properties, which could lead to several clinical benefits, including better physical properties and the prevention of tooth decay. After applying the described methodology, representative articles published in the time period 2011-present were selected and included in the final review, covering the modification of GICs with metallic nanoparticles (Cu, Ag), metallic and metalloid oxide nanoparticles (TiO₂, ZnO, MgO, Al₂O₃, ZrO₂, SiO₂), apatitic nanomaterials, and other nanomaterials or multi-component nanocomposites.

The Suitability of Propolis as a Bioactive Component of Biomaterials

Propolis is a resinous product collected by bees from plant exudates to protect and maintain hive homeostasis. Propolis has been used therapeutically for centuries as folk medicine. Modern research investigating the diversity of the chemical composition and plant sources, biological activity, extraction processes, analytical methods, and therapeutic properties in clinical settings have been carried out extensively since the 1980s. Due to its antimicrobial, anti-inflammatory, and immuno-modulator properties, propolis appears to be a suitable bioactive component to be incorporated into biomaterials. This review article attempts to analyze the potential application of propolis as a biomaterial component from the available experimental evidence. The efficacy and compabitility of propolis depend upon factors, such as types of extracts and types of biomaterials. Generally, propolis appears to be compatible with hydroxyapatite/calcium phosphate-based biomaterials. Propolis enhances the antimicrobial properties of the resulting composite materials while improving the physicochemical properties. Furthermore, propolis is also compatible with wound/skin dressing biomaterials. Propolis improves the wound healing properties of the biomaterials with no negative effects on the physicochemical properties of the composite biomaterials. However, the effect of propolis on the glass-based biomaterials cannot be generalized. Depending on the concentration, types of extract, and geographical sources of the propolis, the effect on the glass biomaterials can either be an improvement or detrimental in terms of mechanical properties such as compressive strength and shear bond strength. In conclusion, two of the more consistent impacts of propolis across these different types of biomaterials are the enhancement of the antimicrobial and the immune-modulator/anti-inflammatory properties resulting from the combination of propolis and the biomaterials.