Effects of Nanosecond Laser Fabrication on Bioactivity of Pure Titanium

We are developing surface modification techniques for dental implants with the aim of reducing the time required to realize good adhesion between bone and implant surfaces. A nanosecond Nd:YVO4 laser was used to modify the surfaces of commercially pure titanium (CP Ti) disks and their bioactivities were then evaluated. The surfaces of the CP Ti disks were covered by lines after laser treatment. This treatment created complex microasperities of titania with rutile and anatase crystal structures. This results in the formation of hydroxyapatite on surfaces immersed in 1.5-times concentrated simulated body fluid for 7 days, whereas no hydroxyapatite was observed on conventionally polished surfaces that were immersed under the same conditions. This indicates that laser treatment improves the bioactivity of CP Ti, which is a critical property for osseointegrated implants.