Abstract
Aim: To develop a novel endodontic cement for use in vital pulp treatment incorporating biomaterials, including chitosan, silk fibroin, and bovine bone hydroxyapatite.
Methods: The experimental cements were designed to have two components: a liquid component that contains 2% (w/v) chitosan and 1% (w/v) silk fibroin; and a powder component composed of different percentages of bovine hydroxyapatite (0%, 20%, 40% and 60%), a set amount of Ta2O5 (20%) as radiopacifier, and a various amount of calcium sulphate (80%, 60%, 40% and 20%) as setting agent. The experimental cements were chemically characterised using inductively coupled plasma mass spectrometry and scanning electron microscopy. Their mechanical properties including compressive strength, radiopacity, setting time, solubility and pH were also tested. The biocompatibility of the cements were tested against ProRoot MTA using human dental pulp cells and human osteogenic sarcoma cells.
Results: The experimental cements had considerably lower compressive strength compared to ProRoot MTA but overall had acceptable physical and mechanical properties, including compressive strength, radiopacity, setting time, solubility, and pH. The experimental cements displayed good overall biocompatibility. All samples significantly improved Saos-2 cell viability and proliferative activity compared to the baseline control. Samples from Group 1 with 60% bovine hydroxyapatite demonstrated significantly lower cytotoxicity in the first 24 hours compared to ProRoot MTA.
Conclusion: The results showed that the experimental endodontic cements containing chitosan, silk fibroin and hydroxyapatite had a positive biological effect on cell viability and proliferative activity, potentially better than ProRoot MTA. However, the physical and mechanical properties of the experimental cements were inferior to ProRoot MTA. Further investigations to improve the mechanical properties are warranted, and animal trials are required to demonstrate the histological response of the materials in vivo.