Femtosecond laser - the finest tool for hard tissue ablation

We report oral cavity specific hard tissue ablation experiments at different fluence values using femtosecond laser. The set-up was composed by a high energy femtolaser, optical and mechanical equipment for focusing and displacement of the beam on the sample surface. Using a lens to focus the beam we have obtained fluence range between 75 J/cm(2) and 0.21 J/cm(2). Samples were human extracted teeth and mandible bone. Created structures were rows. Characterization of ablated structures was made by scanning electron microscope and optical microscope. Ablation areas images show crystalline and regular structures. There are not evidences of material burning under 75 J/cm(2). Generated structures are reproducible, dependent on tissue quality and surface roughness. Dimensions of structures are of tens microns, dependent on beam fluence and material hardness. We appreciate the potential of the method to about 1 micron precision. The results are positive considering the advantages of the method: ablation precision and no collateral damage.