Evaluation of Cell Adhesion and Proliferation of Human Dental Pulp Stem Cells to Different Root End Filling Materials: An In-vitro Study

Abstract

Introduction: Recent advancements in dental materials have led to the development of various restorative cements. The amalgamation of various biomimetic cements becomes necessary to improve the physico-chemical properties of the existing cements. Mineral Trioxide Aggregate (MTA) Plus and Chitosan are two such materials which are combined and chosen to check their effects on dental stem cell adhesion and proliferation. Aim: To compare and evaluate the cell adhesion and proliferation of human dental pulp stem cells on MTA Plus, MTA Plus-Chitosan Conjugate, and Chitosan by directly culturing the cells on the materials. Materials and Methods: This in-vitro study was conducted at the Central Research Laboratory in Department of Conservative Dentistry and Endodontics, S.D.M College of Dental Sciences, Dharwad, Karnataka, India over a period of 1.5 years from the month of June 2020 to December 2021. The samples were divided into four groups: Group A-MTA Plus mixed with the proprietary gel (9 specimens), Group B-MTA Plus mixed with 2% Chitosan gel (9 specimens), Group C-2% Chitosan Gel (9 specimens), and Group D-Control Group (Growth Medium). Non carious extracted permanent human premolars for orthodontic purposes were collected and sectioned for the extraction of pulp tissue. The tissue was placed in a basic medium Dulbecco modified essential medium-High Glucose (DMEM-HG). Dental Pulp Stem Cells were subjected to differentiation using differentiation media (Hi-Media) containing Dexamethasone. Cell proliferation and viability were checked using trypan blue, and cell adhesion was checked using crystal violet under an inverted light microscope. To evaluate if there were any changes in the proliferation of viable cells at 24 hours, 48 hours, and 72 hours among different materials, the Wilcoxon’s Signed-rank Test was used. Statistical significance was set at p≤0.05. Results: The cells were able to adhere to the biomaterial and showed a spindle-shaped morphology, which was observed under the inverted light microscope. ALP activity was measured using a photometer after cell differentiation. MTA Plus-Chitosan conjugate showed a 94% increase in cell proliferation after 48 hours (n=86/91). MTA Plus showed a 91% increase in cell proliferation after 48 hours (n=109/120). Conclusion: Chitosan can be used as a vehicle with MTA since their conjugate showed greater proliferation activity after stem cell culture.

Keywords

• cell proliferation
• chitosan
• mesenchymal stem cell
• odontoblasts