Nanosized hydroxyapatite for periodontal regeneration

Objectives: evaluate the physico-chemical and biological behavior of novel biomimetic nano-sized and nano-dense hydroxyapatites. Methods: the powder form nano-hydroxyapatites were synthesized in order to present averaged physical, chemical and structural properties similar to biological ones, in particular of those of acellular cementum and in order to be applied over diseased cementum in humans after being tested for cytotoxicity and in animal models. They were suspended in PEG on osteoblast-like bone cells for proliferation and methabolism; the biological effect when the material was put in contact with animal collagen tissue was also assessed. Good biotolerance and no inflammatory response was detected.The nano-hydroxyapatites were characterized by means of X-Ray powder Diffraction (Rietveld and structure-independent peak profile analysis), Fourier Transform Infra-Red Spectrometry, and Scanning Electron Microscopy. SEM morphological analysis of sound and diseased root cementum surfaces were performed before and after in-vitro applications of nano-sized hydroxyapatites. Several case reports will be also presented at 12 month showing both clinical and radiographical evaluation. Results: data obtained have shown that it is possible to tailor the morphology and structure of nano-hydroxyapatite with suitable physico-chemical and biological characteristics capable to mimic the normal structure of healthy cementum and clinical cases presented gain of attachment (PAL gain) at 12 months. Conclusion: the study aims at foreseeing possible applications in periodontal tissue regeneration.