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

Autor(es)

Bello-Silva, Marina Stella ^{[1, 2, 3]} ; Wehner, Martin ^[4] ; Eduardo, Carlos de Paula ^[2] ; Lampert, Friedrich ^[1] ; Poprawe, Reinhart ^{[4, 5]} ; Hermans, Martin ^{[4, 5]} ; Esteves-Oliveira, Marcella ^[1]

Afiliação do(s) autor(es)

^[1] RWTH Aachen Univ Hosp, Dept Conservat Dent Periodontol & Prevent Dent, D-52074 Aachen - Germany

^[2] Univ Sao Paulo, Fac Odontol, Dept Restorat Dent, Special Lab Lasers Dent LELO, BR-05508000 Sao Paulo - Brazil

^[3] Nove de Julho Univ, Post Grad Program Biophoton Appl Hlth Sci, BR-01504001 Sao Paulo - Brazil

^[4] Fraunhofer Inst Laser Technol, D-52074 Aachen - Germany

^[5] Rhein Westfal TH Aachen, Chair Laser Technol, D-52074 Aachen - Germany

• Tipo de documento: Artigo Científico
• Fonte: Lasers in Medical Science; v. 28, n. 1, p. 171-184, JAN 2013.
• Citações Web of Science: 32

Resumo

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. (AU)

• Processo FAPESP: 08/00668-3 - Avaliação da qualidade de união entre os tecidos dentais irradiados com lasers de Er:YAG e Er;Cr:YSGG e a resina composta através do teste de nanoinfiltração e de microscopia eletrônica de transmissão
• Beneficiário: Marina Stella Bello Silva
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto