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Pulsed laser beams, of very short duration, appear to be very promising tools for polymer surface processing. Recently we have studied the interaction of picosecond and femtosecond laser radiation in the visible region of the spectrum with synthetic polymer films and we have compared these studies with our similar studies with nanosecond duration laser radiation. Biocompatible polymers have been extensively used for sutures, vascular grafts or bone and other hard tissue replacements. The use of surgical lasers for intervention on biocompatible material - tissue interfaces has attracted a great deal of interest, as both the high intensity, short pulse duration lasers and the prosthetic biomaterials are in increasing use. Our recent ablation studies, using ultrashort laser pulses, of biocompatible materials, are described in this article. Lasers were introduced in medical research in the early sixties but the laser beam ability to remove efficiently and safely soft or hard tissue, the lateral thermal damage and the final surface characteristics are still under investigation. In the past few years, by virtue of their water or water and hydroxyapatite content respectively, exhibit strong absorption restricting residual thermal damage to a relatively small zone. Recently we have investigated the interaction of short pulse laser radiation of picosecond and femtosecond duration with soft and hard tissue, as this unexplored field is expected to be a potential alternative in powerful laser processing of biomedical structures. The experimental results obtained, including ablation rates, ablation wavelength dependence, pulse duration dependence, fluence dependence, etc. are presented. These results are discussed according to simple theoretical models of laser energy absorption and the possible mechanisms of ultrashort pulse laser ablation, which in some cases involves multiphoton photodissociation processes. Finally, the design characteristics of the lasers employed in our experiments, are stated briefly.
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