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Objective The aim of this study was to evaluate surface changes on dental implant systems and ions release after immersion in fluoride and hydrogen peroxide. Methods Ten implant‐abutment assemblies were embedded in acrylic resin and cross‐sectioned along the implant vertical axis. Samples were wet ground and polished. Delimited areas of groups of samples were immersed in 1.23% sodium fluoride gel (F) or in 35% hydrogen peroxide (HP) for 16 min. Gels (n = 3) were collected from the implant surfaces and analyzed by inductively coupled plasma mass spectrometry (ICP‐MS), to detect the concentration of metallic ions released from the implant systems. Selected areas of the abutment and implant (n = 15) were analyzed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Results SEM images revealed surface topographic changes on implant‐abutment joints after immersion in fluoride. Implants showed excessive oxidation within loss of material, while abutment surfaces revealed intergranular corrosion after immersion in fluoride. ICP‐MS results revealed a high concentration of Ti, Al, V ions in fluoride after contact with the implant systems. Localized corrosion of implant systems could not be detected by SEM after immersion in hydrogen peroxide although the profilometry showed increase in roughness. ICP‐MS showed the release of metallic ions in hydrogen peroxide medium after contact with dental implants. Conclusion Therapeutical substances such as fluorides and hydrogen peroxide can promote the degradation of titanium‐based dental implant and abutments leading to the release of toxic ions.

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The aim of this study was to analyze the osteogenic cell behavior on the surface of novel functionally graded titanium-based composites containing bioactive ceramics. Titanium grade V discs (8 × 3 mm) embedding gradual content of hydroxyapatite (TiAlV-HA) or beta-tricalcium phosphate (TiAlV-βTCP) were produced by hot-pressing technique. Titanium-ceramic composite discs and Ti grade V (control group) were placed in contact with human osteoblast culture assays. The morphology and adhesion of osteoblasts were inspected by field emission guns scanning electron microscopy (FEGSEM) while cell viability was assessed by fluorometric method. Alkaline phosphatase (ALP) activity and fluorescent microscopic analyses were used to evaluate mineralization on the test and control discs. FEGSEM images showed cells adhered to Ti6Al4V-ceramic and Ti6Al4V surfaces over a period of 24 h, and therefore, an intense proliferation of osteoblasts and spreading cells was noticed for 7 days. Cell viability increased with time on all the surfaces although TiAlV-βTCP revealed significant higher percentage of cell viability than that recorded for TiAlV-HA (p < 0.01). TiAlV-βTCP also showed the highest hydrophilic character. ALP levels increased on the Ti6Al4V-ceramic surfaces when compared to the control group. Also, a qualitative analysis of mineralization evidenced an increase in mineral content on TiAlV-HA or TiAlV-βTCP groups. Novel functionally graded composites based on Ti grade V and hydroxyapatite or βTCP showed a higher bioactivity in presence of osteoblasts than that recorded on Ti grade V. Also, such functionally graded materials can prevent risks of failures by detachment of bioactive ceramic materials during implant placement. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1923-1931, 2018.

The aim of this study was to characterize the mechanical properties of a bioactive-modified PEEK manufacturing approach for dental implants and to compare the in vitro biological behavior with Titanium alloy (Ti6Al4V) as the reference. PEEK, PEEK with 5% hydroxyapatite (HA), PEEK with 5% beta-tricalcium phosphate (ßTCP) and Ti6Al4V discs were produced using hot pressing technology to create a functionally graded material (FGM). Surface roughness values (Ra, Rz), water contact angle, shear bond strength and Vickers hardness tests were performed. Human osteoblasts and gingival fibroblasts bioactivity was evaluated by a resazurin-based method, alkaline phosphatase activity (ALP) and confocal laser scanning microscopy (CLSM) images of fluorescent-stained fibroblasts. Morphology and cellular adhesion were confirmed using field emission gun-scanning electron microscopy (FEG-SEM). Group comparisons were tested using Anova (Tukey’s post-hoc) α=0.05. All groups presented similar roughness values (P&gt;0.05). Ti6Al4V group was found to have the highest contact angle (P&lt;0.05). Shear bond strength and Vicker’s hardness of different PEEK materials were similar (P&gt;0.05), however mean values in Ti6Al4V group were significantly higher when compared to other groups (P&lt;0.05). Cell viability and proliferation of osteoblast and fibroblast cells were higher in PEEK group (P &lt;0.05). PEEK-ßTCP showed the highest significant ALP activity over time ( P &lt;0.05 at 14 days of culture). An enhanced bone and soft tissue cell behavior on pure PEEK was obtained to the gold standard - Ti6Al4V with equivalent roughness. The results substantiate the potential role of chemical composition rather than physical properties of materials in biological responses. The addition of 5% HA or ßTCP by FGM did not enhance PEEK mechanical properties or periodontal cell behavior.