Soft tissue attachment on sol–gel-treated titanium implants in vivo

Abstract

This study was designed to examine the attachment and reactions of soft tissues to sol-gel-derived TiO2 coatings. In the first experiment, TiO2 coated and uncoated titanium cylinders were placed subcutaneously into the backs of rats for 3, 11 and 90 days. Tissue response and implant surfaces were characterized with routine light microscopy and scanning electron microscopic (SEM) analysis. In the second experiment, TiO2-coated and uncoated discs were implanted subcutaneously into the backs of rats for 14 and 21 days. The discs were pulled out from the implantation sites with a mechanical testing device using a constant speed of 5 mm/min. Rupture force was registered, after which the discs were assigned for SEM and transmission electron microscopic (TEM) analysis. All the coated implants showed immediate contact with the surrounding soft tissues without a clear connective tissue capsule. Significantly better soft tissue response was measured for all the coated compared to the uncoated cylinders (p<0.01). Higher rupture forces were measured for all coated discs, although the differences were not statistically significant. An immediate and tight connection between connective tissue fibroblasts and coatings was noticed in TEM analysis. Our study indicates that TiO2 coatings improve soft tissue attachment on a titanium surface.

Adhesion and proliferation of human fibroblasts on sol‐gel coated titania

“…The sol‐gel treatment had been proven to smoothen the surface topography on the experimental substrates. The surface roughness for TiO 2 surface has been evaluated in our previous work and is estimated as Sa = 0.255 μm, Sq = 0.322 μm12 and this surface smoothness may explain the absence of contact guidance on the coated discs. On the other hand, the strong attachment on the coated surfaces might also have held up the cells from migrating along the surface in the first place 17.…”

“…Thus, the method facilitates the fabrication of coatings with varying bioactivities. TiO 2 coatings have been found to improve soft tissue attachment on cp titanium in vivo with almost absent capsule formation in soft tissue–titanium interface 10–13. The reason for good soft tissue response, lack of capsule formation, and increased connective tissue cell adhesion and spreading is apparently the smooth surface of coating with high‐energy negative surface charge and facilitated adsorption of proteins on sol‐gel‐derived titanium coatings,10, 13 but the actual mechanisms on cellular and molecular biological level are still poorly understood.…”

Adherence of human oral keratinocytes and gingival fibroblasts to nano-structured titanium surfaces

“…However, while effects of modifications on the nanometre level on osteoblast activity have been studied extensively [13,14], knowledge of how nanostructures influence peri-implant soft-tissue healing is currently limited. The few in vivo studies that have been undertaken in rats [15], dogs [16] or humans [17] (Wennerberg et al ) suggest that the use of nanostructured titanium abutment surfaces might improve soft-tissue healing. One in vitro study by Zile et al .…”

Nanofeatured Titanium Surfaces for Dental Implantology: Biological Effects, Biocompatibility, and Safety

“…The coating can also contain fluorohydroxyapatite or fluorapatite to increase the biological activity and reduce resorption rate of the coated layer [86][87][88]. Sol-gel derived nanoporous TiO 2 coatings have been proven to enhance soft Journal of Nanomaterials 5 tissue attachment in rat and dog models [89][90][91]. Similarly, in a human experimental study, results indicated that a significantly greater proportion of oral mucosa came into contact with the nanoporous TiO 2 surface than that with the unmodified surfaces [92].…”