Evaluation of the adhesive strength in dentin after irradiation with Ti:Sapphire ultrashort laser pulses

• Autor(a) principal: PENHA JUNIOR, TARCISO
• Data de Publicação: 2019
• Outros Autores: RODRIGUES, MONICA de A.P., ZEZELL, DENISE M., VIEIRA JUNIOR, NILSON D., SAMAD, RICARDO E., DUTRA-CORREA, MARISTELA, SBFOTON INTERNATIONAL OPTICS AND PHOTONICS CONFERENCE
• Tipo de documento: Artigo de conferência
• Título da fonte: Repositório Institucional do IPEN
• Texto Completo: http://repositorio.ipen.br/handle/123456789/30297

This study was done to evaluate whether the irradiation of dentine with ultrashort laser pulses prior to adhesive procedures contributes to increase the adhesive resistance to microtraction essays. Twenty-four human teeth (third molars) were used, divided into 4 groups (n=6): standard adhesive procedures with etch-rinse adhesive were used in the control group, and in the experimental groups, the dentin was irradiated by 25 fs pulses prior to the adhesive procedures, with varying fluences. One tooth from each group was used to evaluate its surface roughness. After 24h, the teeth were sectioned with perpendicular cuts, producing toothpicks that were submitted to the microtraction test. The results showed that the groups irradiated with fluences under 4 J/cm?? presented similar results among themselves, comparable to the control group, while the group irradiated with 8 J/cm?? showed lower adhesive strength. We propose that the adhesive strength and surface roughness reduction resulting from the fluence increase is probably related to the shielding arising from an electron plasma formation during the ablation, decreasing the material removal efficiency. Nevertheless, the lower energy densities did not affect the adhesiveness, maintaining values similar to the control.