Thermal effects and morphological aspects of varying Er:YAG laser energy on demineralized dentin removal: an in vitro study

Autor(es)

Raucci-Neto, Walter ^[1] ; dos Santos, Carla Raquel ^[2] ; de Lima, Fabricio Augusto ^[3] ; Pecora, Jesus Djalma ^[2] ; Bachmann, Luciano ^[3] ; Palma-Dibb, Regina Guenka ^[2]

Afiliação do(s) autor(es)

^[1] Univ Ribeirao Preto UNAERP, Sch Dent, BR-14096900 Ribeirao Preto, SP - Brazil

^[2] Univ Sao Paulo, Ribeirao Preto Dent Sch, Dept Restorat Dent, BR-14040904 Ribeirao Preto, SP - Brazil

^[3] Univ Sao Paulo, Dept Phys, Ribeirao Preto Sch Philosophy Sci & Literature, BR-14040901 Ribeirao Preto, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Lasers in Medical Science; v. 30, n. 4, p. 1231-1236, MAY 2015.
• Citações Web of Science: 2

Resumo

The aim of this study was to evaluate thermal changes, dentin ablation removal capacity, and morphological aspects of sound and demineralized human dentin surface irradiated with different output energies of an erbium: yttrium-aluminium-garnet (Er:YAG) laser. Eighty sound human tooth specimens were assigned into two groups: demineralized dentin and sound dentin (control group). The dentin groups were subdivided into four subgroups (n = 10) according to the irradiation energy used (120, 160, 200, or 250 mJ) at a constant frequency level of 6 Hz, in focused mode, and under refrigeration. Quantitative analysis of the sound and carious dentin ablation was performed using light microscopy (LM) by measuring (mm) the remaining demineralized tissue with the Axion Vision (TM) software. Qualitative analysis was performed using the images obtained with a scanning electron microscope (SEM), and the temperature increase was recorded with an infrared digital thermometer. The Er:YAG laser promoted a gradual increase in temperature for all groups, and no difference was observed between the sound and demineralized dentin. The groups of 200 and 250 mJ showed the highest values, yet a variation in temperature did not exceed 5 A degrees C. The energy output of 120 mJ selectively removed demineralized tissue when compared to 250 mJ, while also providing more regular surfaces in the cavity preparation. It was concluded that the temperature increase during sound and demineralized dentin removal had a strong positive correlation with the Er:YAG laser energy level output. However, the higher energies used did not present selectivity to the demineralized tissue, and the parameters used did not cause an increase in temperature over 5 A degrees C. (AU)

• Processo FAPESP: 12/02460-6 - Espectroscopia vibracional de tecidos biológicos: diagnóstico de lesões cancerosas e caracterização química de tecidos dentais irradiados com lasers
• Beneficiário: Luciano Bachmann
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 11/07960-4 - Radiometria ótica de lasers, LEDs e lâmpadas emissoras de radiação ultravioleta
• Beneficiário: Luciano Bachmann
• Modalidade de apoio: Auxílio à Pesquisa - Regular