Analysis of the Viability and Morphology of Gingival Cells on Materials Used in Novel Prosthetic Components: In Vitro Study

Abstract

The objective of this in vitro study was to evaluate the viability and morphology of human fibroblasts and keratinocytes cells, both grown on stainless steel (steel) (18Cr14Ni2.5Mo), and polyether-ether-ketone (PEEK) surfaces, hypothesizing the use of these surfaces as novel materials for prosthetic components. Gingival human keratinocytes and gingival human fibroblasts lines were grown on discs made by steel (n = 36), PEEK (n = 36), and titanium (Ti) (Ti6A14V) (n = 36)-control. For viability assay, cultures were grown at 24 hours (TV1), 48 hours (TV2), and 72 hours (TV3) times and evaluated by the colorimetric tetrazolium assay (MTT). For morphology and cell adhesion assays, after 24 hours (TM1), 48 hours (TM2), and 96 hours (TM3) of cell culture, cells were examined by scanning electron microscopy (SEM) and analyzed at magnifications with 500×, 1,000×, and 2,500×. Regarding the viability, the keratinocytes did not present statistical difference on the different materials, in TV1 and TV3 times of culture. Their growth rate increased on all materials, being more expressive in steel; the fibroblasts did not present statistical difference on the different materials, in TV2 and TV3 times of culture. The growth rate of these decreased on all materials, being more expressive in PEEK. The morphology analyses show increase in cell numbers, adequate spreading, and adhesion at all cultivation times (TM1, TM2, and TM3) in both cell lines, on all materials. All materials tested are suitable for use in the manufacture of prosthetic components for implant-supported rehabilitations, considering the limitations of this study. This work analyzes the cellular response of cells present in the human gingiva, as a way to simulate the peri-implant tissue response around novel angular prosthetic components made of stainless steel and PEEK.