Examination of the biocompatibility and anti-microbial activity of coated dental implants

Abstract

Teeth are important to all people for chewing, speech and aesthetics. Tooth decay, periodontal disease and physical trauma or injuries are the main causes of tooth loss. There are different forms of treatment for tooth loss such as dental bridges, removable dentures and dental implants. Dental implants are considered to be better than the other options. They have artificial tooth roots that are placed in the locations of missing teeth. After surgery, osteoblasts attach to the implant and build new bone around the implant in a process known as osseointegration. Titanium alloys (especially Ti6Al4V) are the most widely used biomedical materials in dental and orthopaedic implants due to their excellent biocompatibility, good mechanical properties and corrosion resistance. Although Ti6Al4V alloy is a favourable material, dental implants can fail (i.e. loosen and eventually fall out). Reasons of dental implant failure are microbial infections, poor surgical execution and biomechanical overloading on the implant surface. Thus, the aim of this study was to evaluate whether specific novel implant coatings could improve the biocompatibility and anti-microbial activity of the standard Ti6Al4V alloy. To that end, the cell adhesion, viability and morphology of SaOS-2 (osteoblast-like) cells were investigated after culturing them on samples of Ti6Al4V coated with hydroxyapatite, magnesium oxide and either titanium dioxide or silicon carbide. Morphology of cells was visualized using phalloidin-TRITC (for actin fibres) and DAPI (for the nuclei), whereas viability was determined using propidium iodide (dead cells) and calcein-AM (live cells) and all were viewed using fluorescence microscopy. The disc diffusion (Kirby- Bauer) assay was used to determine potential antimicrobial activities of the novel implant coatings against Candida albicans, Streptococcus sanguinis, Staphylococcus aureus and Escherichia coli.