Biological characterization of implant surfaces - in vitro study

Caracterização biológica de superfície de titânio - estudo in vitro

Abstract

Objective

Evaluate the biological performance of titanium alloys grade IV under different surface treatments: sandblasting and double etching (Experimental surface 1; Exp1, NEODENT); surface with wettability increase (Experimental surface 2; Exp2, NEODENT) on response of preliminary differentiation and cell maturation.

Material and method

Immortalized osteoblast cells were plated on Exp1 and Exp2 titanium discs. The polystyrene plate surface without disc was used as control group (C). Cell viability was assessed by measuring mitochondrial activity (MTT) at 4 and 24 h (n = 5), cell attachment was performed using trypan blue exclusion within 4 hours (n = 5), serum total protein and alkaline phosphatase normalization was performed at 4, 7 and 14 days (n = 5). Data were analyzed using one-way ANOVA and Tukey test.

Result

The values of cell viability were: 4h: C– 0.32±0.01^A; Exp1– 0.34±0.08^A; Exp2– 0.29±0.03^A. 24h: C– 0.43±0.02^A; Exp1– 0.39±0.01^A; Exp2– 0.37±0.03^A. The cell adhesion counting was: C– 85±10^A; Exp1- 35±5^B; Exp2– 20±2^B. The amounts of serum total protein were 4d: C– 40±2^B; Exp1– 120±10^A; Exp2– 130±20^A. 7d: C– 38±2^B; Exp1– 75±4^A; Exp2– 70±6^A. 14 d: C– 100±3^A; Exp1– 130±5^A; Exp2– 137±9^A. The values of alkaline phosphatase normalization were: 4d: C– 2.0±0.1^C; Exp1– 5.1±0.8^B; Exp2– 9.8±2.0^A. 7d: C– 1.0±0.01^C; Exp1– 5.3±0.5^A; Exp2– 3.0±0.3^B. 14 d: C– 4.1±0.3^A; Exp1– 4.4±0.8^A; Exp2– 2.2±0.2^B. Different letters related to statistical differences.

Conclusion

The surfaces tested exhibit different behavior at dosage of alkaline phosphatase normalization showing that the Exp2 is more associated with induction of cell differentiation process and that Exp1 is more related to the mineralization process.

Descriptors:
Titanium surface; mitochondrial colorimetric assay; cell cytotoxicity