No evidence to indicate topographic dependency on bone formation around cp titanium implants under masticatory loading

Microstructural and topographical characterization of different surface treatments of a surgical titanium alloy for dental implants

OBJECTIVE

To perform a topographical characterization of a titanium alloy subjected to different surface treatments using roughness evaluation, scanning electron microscopy, and atomic force microscopy.

MATERIALS AND METHODS

For each group, 6 discs of a titanium alloy had their surfaces modified by 4 treatments. All surfaces were blasted with Al2O3, cleaned, and the specimens were divided into 4 groups: G1, immersion in a standardized acid solution (SAS) (control group); G2, immersion in acetone, followed by immersion in SAS; G3, immersion in acetone, followed by immersion in SAS, followed by immersion in nitric acid; G4, immersion in acetone, followed by immersion in SAS, followed by immersion in sulfuric acid. Roughness parameters were determined with a roughness tester, and data were statistically analyzed using analysis of variance and Tukey tests (α = 5%).

RESULTS

Regarding the roughness parameters, no significant differences were found. Scanning electron microscopy and atomic force microscopy showed irregular surfaces with the presence of particles uniformly deposited on the surfaces.

CONCLUSION

A similar roughness pattern was created for all the groups. The images and topographic profiles indicated that all the groups showed high levels of roughness.

Effects of titanium surface topography on bone integration: a systematic review

AIM

To analyse possible effects of titanium surface topography on bone integration.

MATERIALS AND METHODS

Our analyses were centred on a PubMed search that identified 1184 publications of assumed relevance; of those, 1064 had to be disregarded because they did not accurately present in vivo data on bone response to surface topography. The remaining 120 papers were read and analysed, after removal of an additional 20 papers that mainly dealt with CaP-coated and Zr implants; 100 papers remained and formed the basis for this paper. The bone response to differently configurated surfaces was mainly evaluated by histomorphometry (bone-to-implant contact), removal torque and pushout/pullout tests.

RESULTS AND DISCUSSION

A huge number of the experimental investigations have demonstrated that the bone response was influenced by the implant surface topography; smooth (S(a)<0.5 microm) and minimally rough (S(a) 0.5-1 mum) surfaces showed less strong bone responses than rougher surfaces. Moderately rough (S(a)>1-2 microm) surfaces showed stronger bone responses than rough (S(a)>2 microm) in some studies. One limitation was that it was difficult to compare many studies because of the varying quality of surface evaluations; a surface termed 'rough' in one study was not uncommonly referred to as 'smooth' in another; many investigators falsely assumed that surface preparation per se identified the roughness of the implant; and many other studies used only qualitative techniques such as SEM. Furthermore, filtering techniques differed or only height parameters (S(a), R(a)) were reported.

CONCLUSIONS

* Surface topography influences bone response at the micrometre level. * Some indications exist that surface topography influences bone response at the nanometre level. * The majority of published papers present an inadequate surface characterization. * Measurement and evaluation techniques need to be standardized. * Not only height descriptive parameters but also spatial and hybrid ones should be used.