Effects of fluoridation of porcine hydroxyapatite on osteoblastic activity of human MG63 cells

Abstract

Biological hydroxyapatite, derived from animal bones, is the most widely used bone substitute in orthopedic and dental treatments. Fluorine is the trace element involved in bone remodeling and has been confirmed to promote osteogenesis when administered at the appropriate dose. To take advantage of this knowledge, fluorinated porcine hydroxyapatite (FPHA) incorporating increasing levels of fluoride was derived from cancellous porcine bone through straightforward chemical and thermal treatments. Physiochemical characteristics, including crystalline phases, functional groups and dissolution behavior, were investigated on this novel FPHA. Human osteoblast-like MG63 cells were cultured on the FPHA to examine cell attachment, cytoskeleton, proliferation and osteoblastic differentiation for in vitro cellular evaluation. Results suggest that fluoride ions released from the FPHA play a significant role in stimulating osteoblastic activity in vitro, and appropriate level of fluoridation (1.5 to 3.1 atomic percents of fluorine) for the FPHA could be selected with high potential for use as a bone substitute.

Changes in physicochemical and biological properties of porcine bone derived hydroxyapatite induced by the incorporation of fluoride

“…In addition, our results indicating increased cell attachment are in agreement with studies on synthetic fluoride containing HAp [ 59 ]. In our previous report [ 30 ], the fluoride incorporated BAp was found to promote the proliferation and osteogenic differentiation of MG63 cells, but there was no significant difference in cell attachment on the first day, which was inconsistent with what we observed in the current study. The inconsistency in two independent studies might be due to the slight modification of sample preparation, i.e.…”

“…For instance, in guided tissue regeneration, the physical support from the implanted graft material is vital for the maintenance of the augmented volume and the prevention of soft tissue collapse, which allows more time for the migration of bone cells and subsequent matrix formation. Moreover, the slow and continuous release of fluoride ion at a low concentration may be favorable for new bone formation, as has been reported in our previous study [ 30 ].…”

“…no grinding and compressing of the materials into tablets was done before cell seeding in the current study. As surface topography plays an important role in early protein adsorption and the subsequent adhesion of cells [ 60 ], the previous work may demonstrate the effects of the fluoridated materials on osteoblastic-like cells by the slow release of fluoride ions [ 30 ], while the current study revealed the effects of fluoride ions and surface topography to be both important on biological performance of PHAp and FPHAp.…”

“…Fluoride-substituted HAp, where fluoride ions completely or partially replaced hydroxyl groups in HAp, was reported to have a higher crystal growth capability [ 28 ] and improved biocompatibility, which might make it a more suitable material for the reconstruction of bone defects [ 29 ]. In our previous work, the addition of fluoride in BAp promoted the proliferation and osteogenic activity of osteoblastic-like cells in vitro [ 30 ]. However, the previous study focused on the effects of released fluoride ions from fluorinated BAp, rather than on a systematic evaluation of the physicochemical properties and of the relevant biological properties of the materials, which was of interest in the current study.…”

In Vitro and In Vivo Osteogenic Activity of Titanium Implants Coated by Pulsed Laser Deposition with a Thin Film of Fluoridated Hydroxyapatite

“…Hence, fluoridated hydroxyapatite (FHA), in which the hydroxyl group in hydroxyapatite is selectively substituted for fluorine [ 18 ], has emerged in recent years because it is more stable [ 19 , 20 ] but similarly biocompatible and osteogenic [ 21 , 22 ]. Of note, fluoride ions released from FHA also enhance cell attachment, proliferation, and differentiation [ 23 , 24 ].…”