Development of Novel β-Cyclodextrin Nano-Sized Biomaterials as Calcium Ions Carrier in Dentin Tubules

Objectives: Dentin hypersensitivity, pulpitis, or periodontitis occurred when dentinal tubules were exposed. In pulpless teeth, bacteria could penetrate deeply into the exposed dentinal tubules, and even after root canal therapy, the bacteria in the dentinal tubules might cause the failure of treatment. Therefore, antibacterial materials that could effectively permeate and occlude the dentinal tubules were expected to solve these clinical problems. Our research group developed various biomaterials which could permeate and precipitate in the dentinal tubules. However, these materials preferably permeated in an acidic environment, and the occlusion depth was not deep enough. Based on our previous research results, β-cyclodextrin was chosen as the candidate carrier owing to its surface structure could form charge-screening nanoparticles with positive calcium ions. Besides, it also had good antibacterial properties that could reduce bacterial quorum sensing.
Methods: The loading content of calcium ions encapsulated by β-cyclodextrin was measured by Biovision calorimetric methods. The particle size of the biomaterials was measured by dynamic light scattering (DLS). The morphology of biomaterials was observed by electron microscopy. The degree of permeation in the dentinal tubules was performed by the transwell dentin disc tube model.
Results: The loading concentrations of biomaterials were around 1.92 to 2.49 μg/mL in different pH condition (Figure 1) .The particle size of the biomaterials was 183.7 ± 31.8 nm. TEM morphology demonstrated that the biomaterials were well-suspended (Figure 2). The in vitro permeation profile showed that the calcium ions could permeate through dentin disc model under acidic and neutral condition (Figure 3).
Conclusions: The novel biomaterials based on β-cyclodextrin and calcium ions could act as ion carriers and permeate through the dentinal tubules. We believe β-cyclodextrin nano-sized biomaterials may have great potential in the treatment of related exposed dentin diseases like dentin hypersensitivity or root canal treatment. We would further investigate the crystallization of these biomaterials under different pH conditions and try to combine the antibacterial and anti-inflammatory agents with these biomaterials for more comprehensive applications.