Scanning electron microscopy and ablation rates of hard dental tissue using 350-fs and 1-ns laser pulses

Lasers are currently limited in their ability to remove hard tissue. Furthermore, many laser systems, such as the long pulse infrared lasers used to ablate bone or hard dental tissue, also generate unacceptable heat levels and cause collateral tissue damage. Ultrashort pulse lasers, however, are highly efficient, quiet, and relatively free of charge. With recent developments now allowing operation at high pulse repetition rates, ultrashort pulse systems can yield significant material volume removal which can potentially match or even exceed conventional technology while still maintaining the minimal collateral damage characteristics. In this paper, the interaction characteristics of two pulse regimes with enamel and dentin: 350 fs pulse ablation of hard dental tissues is compared to the interaction with one nanosecond pulses. Ablation rates were characterized and surface morphology, and structure were evaluated using a scanning electron microscope.