Regenerative potential and anti-bacterial activity of tetracycline loaded apatitic nanocarriers for the treatment of periodontitis

Current treatment of periodontal infections includes mechanical debridement, administration of antibiotics and bone grafting. Oral administration of antibiotics results in undesirable side effects, while current modes of local administration are affected by problems concerning allergic response to the polymeric carrier agents. We have developed an osteoconductive drug delivery system composed of apatitic nanocarriers capable of providing sustained delivery of drugs in the periodontium. Calcium deficient hydroxyapatite (CDHA) nanocarriers of different Ca/P ratios were synthesized and characterized using the x-ray diffraction method, transmission electron microscopy, inductively coupled plasma atomic emission spectroscopy, Fourier transform infrared spectroscopy and the BET gas isotherm method. Loading and release studies performed with tetracycline showed a sustained release of up to 88% in phosphate buffered saline over a period of five days. Antibacterial activity studies showed that the tetracycline loaded CDHA (TC-CDHA) nanocarriers were effective against S. aureus and E. coli bacteria. The biocompatibility of the TC-CDHA nanocarriers was demonstrated using an alamar blue assay and further characterized by cell uptake studies. Interestingly, cell uptake of drug loaded CDHA also increased the cellular proliferation of human periodontal ligament fibroblast cells. Hence, it can be concluded that the CDHA nanocarriers are ideal drug delivery agents and have bone regenerative potential for local periodontal applications.