Effect of nanoporous TiO2 coating and anodized Ca2+ modification of titanium surfaces on early microbial biofilm formation

Abstract

BackgroundThe soft tissue around dental implants forms a barrier between the oral environment and the peri-implant bone and a crucial factor for long-term success of therapy is development of a good abutment/soft-tissue seal. Sol-gel derived nanoporous TiO2 coatings have been shown to enhance soft-tissue attachment but their effect on adhesion and biofilm formation by oral bacteria is unknown.MethodsWe have investigated how the properties of surfaces that may be used on abutments: turned titanium, sol-gel nanoporous TiO2 coated surfaces and anodized Ca2+ modified surfaces, affect biofilm formation by two early colonizers of the oral cavity: Streptococcus sanguinis and Actinomyces naeslundii. The bacteria were detected using 16S rRNA fluorescence in situ hybridization together with confocal laser scanning microscopy.ResultsInterferometry and atomic force microscopy revealed all the surfaces to be smooth (Sa ≤ 0.22 μm). Incubation with a consortium of S. sanguinis and A. naeslundii showed no differences in adhesion between the surfaces over 2 hours. After 14 hours, the level of biofilm growth was low and again, no differences between the surfaces were seen. The presence of saliva increased the biofilm biovolume of S. sanguinis and A. naeslundii ten-fold compared to when saliva was absent and this was due to increased adhesion rather than biofilm growth.ConclusionsNano-topographical modification of smooth titanium surfaces had no effect on adhesion or early biofilm formation by S. sanguinis and A. naeslundii as compared to turned surfaces or those treated with anodic oxidation in the presence of Ca2+. The presence of saliva led to a significantly greater biofilm biovolume but no significant differences were seen between the test surfaces. These data thus suggest that modification with sol-gel derived nanoporous TiO2, which has been shown to improve osseointegration and soft-tissue healing in vivo, does not cause greater biofilm formation by the two oral commensal species tested than the other surfaces.

Titanium Oxide Antibacterial Surfaces in Biomedical Devices

“…Lower Ag-containing coatings exhibited in vitro antibacterial activity with no cytotoxicity, while higher Ag concentrations had a cytotoxic effect. These two examples allow us to draw some main conclusions: the anodization process can be effectively applied for titanium modification and coating preparation for biomedical applications, taking advantage of both the morphological and chemical results of such treatments, since these films show controlled porosity, morphology, chemical composition, and allotropic structure (50,(89)(90)(91)(92). Anodic modification technology thus appears interesting when complex devices made of Ti alloys need to be treated in order to obtain antibacterial properties.…”

Effects of titania nanotubes with or without bovine serum albumin loaded on human gingival fibroblasts

“…Numerous studies [2][3][4][5] have demonstrated that osseointegration is facilitated by surface modifications. Over time, the surface designs of the endosseous and transmucosal areas have dynamically changed to enable faster integration after implantation and improve long-term bone maintenance; long-term bone maintenance relies heavily on the surface modification of the transmucosal area because the surface positively affects the three functions of the implants: the attachment of soft tissue, 6,7 the inhibition of bacterial biofilm adhesion, 8,9 and the preservation of the crestal bone.…”

Microcosm Biofilm Formation on Titanium Surfaces

“…Initial biofilm formation may be influenced by the implant surface and the adhesion of microorganisms seems to be directly proportional to surface roughness 35,43,[45][46][47][48][49][50][51] . Other studies also confirm the relationship between surface roughness and the efficiency for osseointegration [52][53][54][55] . Thus, the rougher the surface, the larger the accumulation of biofilm 46,48 , and the greater the chances for clinical failure due to the interplay between these factors.…”