Ultra-Short Pulse Laser Ablation of Biological Hard Tissue and Biocompatibles

The application of ultra-short pulse lasers (USPLs) to biological hard tissue and compatible materials (like for dental restoration) in order to process cavities and more complicated structures is not yet a routine technique which can soon be implemented into practice. Its advantages, however, cover the feasibility of avoidance of collateral damage (i.e. thermal and shock wave), the creation of geometrically fully versatile and precise structures, and the option of spectroscopic feedback. In this paper, new data are presented concerning ablation rates and ablation thresholds of human and bovine dental hard tissue, dental composites and bone, i.e. compacta, spongiosa and cartilage, being ablated by various scanned USPLs with different pulse durations. The data give evidence that even ps pulses yield very useful results, and selective ablation may be beneficial for practical application. The morphology of the cavities yielded by different scanning techniques is analyzed via environmental scanning electron microscopy.