TY - JOUR
T1 - Mechanism of dye-enhanced pulsed laser ablation of hard tissues
T2 - Implications for dentistry
AU - Esenaliev, Rinat
AU - Oraevsky, Alexander
AU - Rastegar, Sohi
AU - Frederickson, Chris
AU - Motamedi, Massoud
N1 - Funding Information:
Manuscript received October 16, 1996; revised January 16, 1997. This work was supported in part by the National Institutes of Health under Grant 2R44-DE-10687, the Whitaker Foundation, and The Department of Energy Centers of Excellence for Medical Laser Applications. R. Esenaliev is with the Biomedical Laser and Spectroscopy Program, University of Texas Medical Branch, Galveston, TX 77555 USA. He is also with the Department of Electrical and Computer Engineering, Rice University, Houston, TX 77251 USA. A. Oraevsky is with the Department of Electrical and Computer Engineering, Rice University, Houston, TX 77251 USA. S. Rastegar is with the Bioengineering Program, Texas A&M University, College Station, TX 77843 USA. C. Frederickson is with the MicroFab Corporation, Plano, TX 77276 USA. M. Motamedi is with the Biomedical Laser and Spectroscopy Program, University of Texas Medical Branch, Galveston, TX 77555 USA. Publisher Item Identifier S 1077-260X(96)09696-7.
PY - 1996/12
Y1 - 1996/12
N2 - Alexandrite laser ablation of enamel enhanced by indocyanine green dye was studied. Microjet system was employed to deliver precisely measured small amounts of absorbing dye solution to the site of irradiation. A sequence of physical phenomena involved in dye-enhanced laser ablation of dental enamel was revealed when laser pulse profiles were compared with the profiles of laser-induced pressure, laser-induced plasma, and ablation plume kinetics. To understand photomechanical effects on the enamel ablation, the absolute values of pressure waves were measured by calibrated wide-band acoustic transducer. Absolute amplitude and temporal profile of pressure waves, plasma emission, ablation plume kinetics, ablation efficiency, and crater quality under free-running and Q-switched ablation of enamel were studied. It was found that there is an optimal dye solution volume (100-200 nL) when the maximum ablation efficiency (30 μm/pulse) can be obtained. It was shown that the ablation efficiency under Q-switched laser irradiation is approximately one order of magnitude lower than that under free-running ablation. It was shown that Q-switched enamel ablation with dye solution is caused by the powerful recoil pressure wave with the amplitude 3-6.5 kbar. In contrast, dye-enhanced free-running enamel ablation is caused by plasma-mediated evaporation of enamel and accompanied by recoil pressure waves of lower amplitude (0.5-1 kbar) that is below mechanical damage threshold in enamel. Uneven crater walls after Q-switched ablation were observed by scanning electron microscopy (SEM). Free-running ablation makes precise craters with smooth and even crater walls.
AB - Alexandrite laser ablation of enamel enhanced by indocyanine green dye was studied. Microjet system was employed to deliver precisely measured small amounts of absorbing dye solution to the site of irradiation. A sequence of physical phenomena involved in dye-enhanced laser ablation of dental enamel was revealed when laser pulse profiles were compared with the profiles of laser-induced pressure, laser-induced plasma, and ablation plume kinetics. To understand photomechanical effects on the enamel ablation, the absolute values of pressure waves were measured by calibrated wide-band acoustic transducer. Absolute amplitude and temporal profile of pressure waves, plasma emission, ablation plume kinetics, ablation efficiency, and crater quality under free-running and Q-switched ablation of enamel were studied. It was found that there is an optimal dye solution volume (100-200 nL) when the maximum ablation efficiency (30 μm/pulse) can be obtained. It was shown that the ablation efficiency under Q-switched laser irradiation is approximately one order of magnitude lower than that under free-running ablation. It was shown that Q-switched enamel ablation with dye solution is caused by the powerful recoil pressure wave with the amplitude 3-6.5 kbar. In contrast, dye-enhanced free-running enamel ablation is caused by plasma-mediated evaporation of enamel and accompanied by recoil pressure waves of lower amplitude (0.5-1 kbar) that is below mechanical damage threshold in enamel. Uneven crater walls after Q-switched ablation were observed by scanning electron microscopy (SEM). Free-running ablation makes precise craters with smooth and even crater walls.
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U2 - 10.1109/2944.577306
DO - 10.1109/2944.577306
M3 - Article
AN - SCOPUS:0030360919
SN - 1077-260X
VL - 2
SP - 836
EP - 846
JO - IEEE Journal of Selected Topics in Quantum Electronics
JF - IEEE Journal of Selected Topics in Quantum Electronics
IS - 4
ER -