Phenotype expression of human bone cells cultured on implant substrates

107

Commercially pure titanium (cpTi), titanium alloys, and steel are often used for dental and orthopedic implants. In these applications titanium is considered the "gold standard." However, tissue reactions around titanium implants and the changing trend to leave orthopedic devices in the body have led to a new examination of the preferred material. This in vitro study tested the behavior of osteoblasts on cpTi, Ti-6Al-7Nb, and stainless steel with surface designs similar to clinical implants. After surface characterization by scanning electron microscopy and profilometry, cell proliferation and the differentiation parameters of alkaline phosphatase (ALP) activity and osteocalcin were measured. For all materials tested, the growth curves showed a similar kinetic. On Ti-6Al-7Nb, ALP activity was significantly lower when compared with steel, and cpTi and did not change over the time. ALP activity increased moderately on steel and cpTi. Osteocalcin levels were higher on both titanium materials than on steel. Based on undisturbed cell growth and the relatively high alkaline phosphatase and osteocalcin levels, we suggest that cpTi provides the best biocompatibility with regard to proliferation, in addition to more reliable early and late differentiation markers of human osteoblasts in vitro.

Section: Introductionmentioning

confidence: 99%

Proliferation and differentiation parameters of human osteoblasts on titanium and steel surfaces

Schmidt

Ignatius

Claes

2000

107

“…[14][15][16][17] Previous studies have provided information regarding cellular response to implant materials by evaluating ECM component neosynthesis and degradation and TGF ␤ activity by human bone cells in vitro. 18,19 Although these studies provide valuable information about cellular response to implant material, many experimental problems need to be solved. First, in the previous studies the cytotoxicity of materials was evaluated using bone cells in vitro.…”

Section: Introductionmentioning

confidence: 99%

Biocompatibility of alloys used in orthodontics evaluated by cell culture tests

Locci

Marinucci

Lilli

et al. 2000

Self Cite

The cytotoxicity of the most common alloys used in orthodontic appliances was determined by cell culture testing. Human gingival fibroblasts were cultured on 304 and 316 stainless steel, on brazing alloy composed of palladium (Pd), copper (Cu), and silver (Ag), and on plastic substrate (control). Studies were carried out with SEM and radiolabeled precursor incorporation. Cells were cultured in MEM without serum but with the addition of (3)H-thymidine to evaluate cell proliferation and (3)H-glucosamine to evaluate glycosaminoglycan (GAG) synthesis and secretion in the culture medium. Moreover, gingival fibroblasts were cultured in the presence of some metal ions generally released by orthodontic appliances to evaluate the cytotoxic effects of single ions. Morphologic observations with SEM and radiolabeled incorporation studies showed that 304 and 316 stainless steel were more biocompatible than the brazing alloy. Among the metal ions tested, Ag and Pd, constituents of the brazing alloy, showed the highest cytotoxicity.

“…Quantitative and qualitative alterations of GAG may be induced by modifying the extracellular environment that alters connective tissue cell metabolism. [38][39][40][41][42][43][44] Therefore, any variation in GAG composition can influence the tissue's state of health. Both the whole appliance and the single components of the appliance reduced the cellular and extracellular accumulation of GAG.…”

Section: Discussionmentioning

confidence: 89%

In vitro cytotoxic effects of orthodontic appliances

Locci

Lilli

Marinucci

et al. 2000

The objective of this study was to evaluate the effects of an orthodontic appliance and of its components (brackets, bands, and arch wires) on some cell functions. Fibroblasts were cultured either in the presence of one unwashed orthodontic appliance, or one orthodontic appliance immersed in MEM for 28 days before use (washed appliance), or in the presence of MEM in which the appliances had been immersed. At the end of in vitro maintenance, morphological studies were carried out with SEM and TEM. Cell proliferation and GAG synthesis and secretion by radio-labeled precursors were assessed. The data indicated that unwashed appliances were more cytotoxic than washed ones. Moreover, the arch wire was the most biocompatible component of the orthodontic appliance, and the bracket was the least biocompatible. A comparative study into the effects on cell proliferation of the most common metal ions released by the appliances was also carried out. At the concentration released by one orthodontic appliance immersed for 28 days, the highest reduction in DNA synthesis was observed in the presence of Cu(++).