Characteristics of calculus fragmentation with Er:YAG laser light emitted by an infrared hollow optical fiber with various sealing caps

We have experimentally quantified calculus fragmentation by Er:YAG laser light. Er:YAG laser light was delivered to an underwater target through a sealed hollow optical fiber. Fragmentation efficiency was obtained for an alumina ball used as a calculus model when sealing caps with various focusing effects were used. Three types of human calculus were analyzed, and their absorption properties at the wavelength of Er:YAG laser light were obtained. The relationships among the absorption properties, calculus constituents, and fragmentation efficiency are discussed.