Development of TiF4-Dendrimer complex gel as an anti-demineralization agent for dentin: An in vitro study

The anti-caries effects of titanium tetrafluoride (TiF4) are well-documented, but its low pH challenges clinical application. This study evaluated PEG-citrate dendrimer as a carrier to enhance TiF4 stability and efficacy.

PEG-citrate dendrimer and TiF4-dendrimer gel were synthesized, and their structures confirmed using Fourier Transform Infrared Spectroscopy (FTIR), Hydrogen Nuclear Magnetic Resonance (1H NMR), and Liquid Chromatography-Mass Spectrometry (LC-MS). Thirty-six intact human teeth were prepared, randomly divided into three groups (n = 12) and subjected to pH cycling with the following treatments: titanium tetrafluoride (T), dendrimer (D), and dendrimer with TiF4 (TD). Vickers microhardness and Raman spectroscopy evaluated dentin demineralization. EDS analysis measured titanium and fluoride penetration into dentin in T and TD groups and mineral content (calcium and phosphorus) in all groups.

The T group showed the highest microhardness loss (p < 0.001), followed by D and TD groups. EDS analysis revealed no significant difference in titanium and fluoride content between the surface and subsurface in TD (p = 0.344), while T had more titanium on the surface (p < 0.001). TD had higher subsurface calcium content compared to T (p = 0.008). Raman spectroscopy revealed significant changes in phosphate-to-amide and carbonate-to-amide ratios before and after pH cycling in all groups (p < 0.001), with no statistical differences among the groups.

Using dendrimer as a carrier for TiF4 increased pH and enhanced TiF44 ability to limit dentin demineralization and microhardness loss.

The application of the newly-developed TiF4-dendrimer gel might be an effective approach to prevent/ limit dentin demineralization and dentin caries.