HGF-1 proliferation on titanium dental implants treated with laser melting technology

Titanium and its alloys are currently the most common dental implant materials. For the best bone-implant contact, machined titanium is subjected to various surface treatments. In the present study, proliferation of human gingivial fibroblast (HGF-1) cells on Grade 5 titanium disks covered with Grade 23 titanium by selective laser melting technology was evaluated.

The main aim was to provide a novel surface procedure providing more biocompatible external structure with a biomechanically intact inner structure and increasing cell proliferation.

Forty-eight titanium Grade 5 machined disks with 5 mm of diameter was divided into four groups. Group 1, also known as the control group, was not subjected to any surface treatment. Group 2 was treated with sand-blasted, large-grid, acid-etching (SLA) technique and Group 3 was treated with selective laser melting (SLM) method. Group 4 was treated with both SLM and SLA. The surface topography was analyzed using scanning electron microscope and the roughness of the samples was evaluated via optic profilometer. Additionally, optical tensiometer was used to measure the surface wettability. To obtain further insights on biocompability of the samples, HGF-1 cell viability at 48 h was assessed with MTT assay. These results were also confirmed by fluorescent staining. Results: Although Ra value and wettability of Group 4 were the highest amongst the samples handled, based on 48 h MTT results and fluorescent staining, highest cell proliferation was observed in Group 3.

It was verifed that the surface topography, roughness, and wettability are all crucial factors on healthy cell populations. Therefore, it was concluded that disks treated with SLM were shown to express the most suitable condition for biocompability.