<title>Influence of water spray on Er:YAG ablation of hard dental tissues</title>

Abstract

Influence of water-spray cooling on the efficiency of erbium laser ablation of hard dental tissues is investigated experimentally. Consecutive pulses from a dental Er:YAG laser system are applied to dentin and enamel surface in vitro. Depths and diameters of the resulting craters, obtained with and without the use of a pressurized air/water spray, are compared at single-pulse fluences from 10 to 140 J/cm<SUP>2</SUP>. Similar measurements are performed also with direct drilling of enamel with a fiber tip. The results show that direct interaction of the cooling water with the laser radiation increases the ablation efficiency for enamel, especially in fiber-tip drilling.