Biological response of human bone marrow mesenchymal stem cells to fluoride-modified titanium surfaces.
OBJECTIVE
The aim of the present study was to examine the behaviour of human bone marrow-derived mesenchymal stem cells (BM-MSC) to fluoride-modified grit-blasted (F-TiO) titanium surfaces compared with grit-blasted ones (TiO).


METHODS
Implant surfaces were analysed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). BM-MSC were isolated from healthy donors and grown on the implant surfaces. Cell adhesion and proliferation, type I collagen (Col I) synthesis, osteoblastic differentiation (in terms of alkaline phosphatase activity, osteocalcin synthesis and extracellular matrix mineralization) were assessed. Furthermore, the ability to affect the osteoblastic/osteoclastic balance in terms of osteoprotegerin (OPG) and activator of nuclear factor κ B ligand (RANKL) ratio was investigated.


RESULTS
F-TiO surface showed higher S(a) values (P<0.05) and the presence of nano-scale structures at the AFM and SEM analysis. Comparable cell morphology and similar adhesion values on both surfaces were detected at early time, whereas higher proliferation values on F-TiO samples were observed at 7 and 10 days. Increased Col I and OPG levels for cells grown on F-TiO were found, whereas RANKL was not detectable in any of the conditioned media. BM-MSC showed a similar expression of early and late osteogenic markers on both TiO and F-TiO surfaces.


CONCLUSIONS
The results of the present study show that the chemical and micro/nano-scale modifications induced by fluoride treatment of TiO-grit blasted surfaces stimulate the proliferation and the extracellular matrix synthesis by BM-MSC, as well as the increase of OPG synthesis, thus preventing osteoclast activation and differentiation.
Guida
Luigi
L
Department of Odontostomatological, Orthodontic and Surgical Disciplines, Second University of Naples, Naples, Italy. luigi.guida@unina2.it
Annunziata
Marco
M
Rocci
Antonio
A
Contaldo
Maria
M
Rullo
Rosario
R
Oliva
Adriana
A
D002448:Cell Adhesion; D002454:Cell Differentiation; D049109:Cell Proliferation; D003094:Collagen / Q000096:biosynthesis; D015921:Dental Implants; D004797:Enzyme-Linked Immunosorbent Assay; D005109:Extracellular Matrix / Q000378:metabolism; D005459:Fluorides / Q000737:chemistry*; D006801:Humans; D059630:Mesenchymal Stem Cells / Q000378:metabolism*; D018625:Microscopy, Atomic Force; D010006:Osteoblasts / Q000166:cytology* / Q000378:metabolism; D015675:Osteocalcin / Q000096:biosynthesis; D010010:Osteoclasts / Q000166:cytology* / Q000378:metabolism; D053245:RANK Ligand / Q000378:metabolism; D012984:Software; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
D015921:Dental Implants; D053245:RANK Ligand; D015675:Osteocalcin; D003094:Collagen; D014025:Titanium; D005459:Fluorides; C032240:titanium tetrafluoride