Treatment of Periodontal Defects with Novel Bioactive Glass Containing Strontium

Objectives: To investigate the role of phosphate and strontium content on the bioactivity in order to develop improved bioactive glasses for the treatment of periodontal bony defects. Strontium is known to up-regulate osteoblast and down-regulate osteoclast.

Methods: The glasses in the system of (SiO₂-P₂O₅-CaO-Na₂O-SrO) with varying phosphate content and 10% of strontium substituted for calcium on a molar basis were synthesized via the melt-quench route.The glass was ground and sieved to obtain particles size between 100 and 400 µm.The glass powder was analysed by (Fourier transform-infrared spectroscopy) FTIR and (X-ray diffraction) XRD both before and after immersion in Tris buffer solution for the purpose of investigating glass bioactivity and its amorphous structure.Glass particles size was determined by Scanning Electron Microscopy(SEM).The pH change after immersion in Tris buffer solution was measured at specific time points (4,6,8,24 and 72 hours).Guantitative analysis of the Ca,P,Na,Si and Sr ions were detected by (Inductively couple plasma-optical emission spectroscopy) ICP-OES technique.

Results: XRD patterns and FTIR spectra of untreated glasses indicated that all glasses were amorphous. FTIR and XRD revealed the formation of apatite upon immersion.The pH values after immersion increased slightly during the experiment.The speed of apatite formation and the amount of apatite formed increased with phosphate content of the glass.

Conclusions: The present study showed that the phosphate content was overriding factor in terms of increasing the glass bioactivity as well as reducing the rapid pH rise,whereas strontium content illustrated a little influence on the glass bioactivity.However, further cell culture studies may demonstrate the biological benefit of strontium.