Lasers in Medical Science

, Volume 28, Issue 1, pp 171–184 | Cite as

Precise ablation of dental hard tissues with ultra-short pulsed lasers. Preliminary exploratory investigation on adequate laser parameters

  • Marina Stella Bello-Silva
  • Martin Wehner
  • Carlos de Paula Eduardo
  • Friedrich Lampert
  • Reinhart Poprawe
  • Martin Hermans
  • Marcella Esteves-Oliveira
Original Article


This study aimed to evaluate the possibility of introducing ultra-short pulsed lasers (USPL) in restorative dentistry by maintaining the well-known benefits of lasers for caries removal, but also overcoming disadvantages, such as thermal damage of irradiated substrate. USPL ablation of dental hard tissues was investigated in two phases. Phase 1—different wavelengths (355, 532, 1,045, and 1,064 nm), pulse durations (picoseconds and femtoseconds) and irradiation parameters (scanning speed, output power, and pulse repetition rate) were assessed for enamel and dentin. Ablation rate was determined, and the temperature increase measured in real time. Phase 2—the most favorable laser parameters were evaluated to correlate temperature increase to ablation rate and ablation efficiency. The influence of cooling methods (air, air–water spray) on ablation process was further analyzed. All parameters tested provided precise and selective tissue ablation. For all lasers, faster scanning speeds resulted in better interaction and reduced temperature increase. The most adequate results were observed for the 1064-nm ps-laser and the 1045-nm fs-laser. Forced cooling caused moderate changes in temperature increase, but reduced ablation, being considered unnecessary during irradiation with USPL. For dentin, the correlation between temperature increase and ablation efficiency was satisfactory for both pulse durations, while for enamel, the best correlation was observed for fs-laser, independently of the power used. USPL may be suitable for cavity preparation in dentin and enamel, since effective ablation and low temperature increase were observed. If adequate laser parameters are selected, this technique seems to be promising for promoting the laser-assisted, minimally invasive approach.


Ablation Dentin Enamel Femtosecond Laser Picosecond 



The authors would like to express their gratitude to DAAD and CAPES (BEX3095/08-8) for their financial support of the sandwich-type doctor program, FAPESP (2008/00668-3) for the PhD scholarship, and Washington Steagall Jr. for the statistical analysis.


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Copyright information

© Springer-Verlag London Ltd 2012

Authors and Affiliations

  • Marina Stella Bello-Silva
    • 1
    • 2
    • 3
  • Martin Wehner
    • 4
  • Carlos de Paula Eduardo
    • 2
  • Friedrich Lampert
    • 3
  • Reinhart Poprawe
    • 4
    • 5
  • Martin Hermans
    • 4
    • 5
  • Marcella Esteves-Oliveira
    • 3
  1. 1.Post Graduate Program in Biophotonics Applied to Health SciencesNove de Julho UniversitySão PauloBrazil
  2. 2.Special Laboratory for Lasers in Dentistry—LELO, Department of Restorative DentistryFaculdade de Odontologia da Universidade de São PauloSão PauloBrazil
  3. 3.Department for Conservative Dentistry, Periodontology and Preventive DentistryRWTH Aachen University HospitalAachenGermany
  4. 4.Fraunhofer Institute for Laser TechnologyAachenGermany
  5. 5.Chair for Laser TechnologyRWTH Aachen UniversityAachenGermany

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