IADR Abstract Archives
Characterization of Eggshell-derived Hydroxyapatite and its Biocompatibility in Oryctolagus cuniculus
Objectives: Hydroxyapatite (Ca10(PO4)6(OH)2) is exceptionally associated with the bony apatite structure. Two-wall infrabony defects caused by periodontitis can be treated by placement of bone graft material to induce regeneration. This study evaluated and analyzed the biocompatibility, cytotoxicity, and regenerative capacity of an economical bone replacement graft utilized from eggshell-derived hydroxyapatite (EDHA).
Methods: The hen eggshells were locally sourced and then processed as a biomaterial before experimentation. Oryctolagus cuniculus (n=16) with a mean weight of 2.3±0.42kg were assigned to two groups: untreated group without EDHA and treated group which received EDHA. Using a low speed carbide bur, a 4mm two-wall bone defect was surgically-induced in the mesio-buccal alveolar bone of the maxillary central incisors of the rabbits in both groups. Physico-chemical characterization of EDHA was examined using pH analysis, Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), and quantitative cell culture and viability assay. Assessment of bone regeneration was done by analyzing changes in clinical attachment level (CAL) and radiographic bone level (RBL) at 4th and 8th weeks post-operative.
Results: The results of CAL (P<0.05) and RBL (P<0.05) showed significant changes (Mann-Whitney U-test and Wilcoxon matched-pairs test) in bone regeneration of the EDHA-treated defect site at 4-weeks post-operative relative to baseline. EDHA had an alkaline pH (12.573+0.082) which is associated with rapid bone mineralization. EDHA also exhibited inorganic components comparable to human bone. FT-IR analysis showed presence of chemical groups in the hydroxyapatite structure: phosphate at 1050.50cm-1 and 1094.13cm-1, hydrogen phosphate at 871.32cm-1, carbonate at 1418.18cm-1 and 1470.08cm-1, and hydroxide at 3407.76cm-1 and 3641.41cm-1. Cytotoxicity result (77%) authenticated EDHA as non-cytotoxic (ISO 10993-5:2009). EDHA at 80,000x magnification is sized at 100nm, verifying it as a nanoparticle.
Conclusions: Confirmed by the results of this study, EDHA was a biocompatible, non-cytotoxic, nanosized bone replacement graft that facilitated bone regeneration in the surgically-induced two-wall defect.
Methods: The hen eggshells were locally sourced and then processed as a biomaterial before experimentation. Oryctolagus cuniculus (n=16) with a mean weight of 2.3±0.42kg were assigned to two groups: untreated group without EDHA and treated group which received EDHA. Using a low speed carbide bur, a 4mm two-wall bone defect was surgically-induced in the mesio-buccal alveolar bone of the maxillary central incisors of the rabbits in both groups. Physico-chemical characterization of EDHA was examined using pH analysis, Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), and quantitative cell culture and viability assay. Assessment of bone regeneration was done by analyzing changes in clinical attachment level (CAL) and radiographic bone level (RBL) at 4th and 8th weeks post-operative.
Results: The results of CAL (P<0.05) and RBL (P<0.05) showed significant changes (Mann-Whitney U-test and Wilcoxon matched-pairs test) in bone regeneration of the EDHA-treated defect site at 4-weeks post-operative relative to baseline. EDHA had an alkaline pH (12.573+0.082) which is associated with rapid bone mineralization. EDHA also exhibited inorganic components comparable to human bone. FT-IR analysis showed presence of chemical groups in the hydroxyapatite structure: phosphate at 1050.50cm-1 and 1094.13cm-1, hydrogen phosphate at 871.32cm-1, carbonate at 1418.18cm-1 and 1470.08cm-1, and hydroxide at 3407.76cm-1 and 3641.41cm-1. Cytotoxicity result (77%) authenticated EDHA as non-cytotoxic (ISO 10993-5:2009). EDHA at 80,000x magnification is sized at 100nm, verifying it as a nanoparticle.
Conclusions: Confirmed by the results of this study, EDHA was a biocompatible, non-cytotoxic, nanosized bone replacement graft that facilitated bone regeneration in the surgically-induced two-wall defect.