title: Biochemical changes on the repair of surgical bone defects grafted with biphasic synthetic micro-granular HA + β-tricalcium phosphate induced by laser and LED phototherapies and assessed by Raman spectroscopy.
abstract: This work aimed the assessment of biochemical changes induced by laser or LED irradiation during mineralization of a bone defect in an animal model using a spectral model based on Raman spectroscopy. Six groups were studied: clot, laser (λ = 780 nm; 70 mW), LED (λ = 850 ± 10 nm; 150 mW), biomaterial (biphasic synthetic micro-granular hydroxyapatite (HA) + β-tricalcium phosphate), biomaterial + laser, and biomaterial + LED. When indicated, defects were further irradiated at a 48-h interval during 2 weeks (20 J/cm2per session). At the 15th and 30th days, femurs were dissected and spectra of the defects were collected. Raman spectra were submitted to a model to estimate the relative amount of collagen, phosphate HA, and carbonate HA by using the spectra of pure collagen and biomaterials composed of phosphate and carbonate HA, respectively. The use of the biomaterial associated to phototherapy did not change the collagen formation at both 15 and 30 days. The amount of carbonate HA was not different in all groups at the 15th day. However, at the 30th day, there was a significant difference (ANOVA, p = 0.01), with lower carbonate HA for the group biomaterial + LED compared to biomaterial (p < 0.05). The phosphate HA was higher in the groups that received biomaterial grafts at the 15th day compared to clot (significant for the biomaterial; p < 0.01). At the 30th day, the phosphate HA was higher for the group biomaterial + laser, while this was lower for all the other groups. These results indicated that the use of laser phototherapy improved the repair of bone defects grafted with the biomaterial by increasing the deposition of phosphate HA.
authors.affiliation: Center of Biophotonics, School of Dentistry, Federal University of Bahia-UFBA, Av. Araújo Pinho, 62, Canela, Salvador, BA, 40110-150, Brazil. albp@ufba.br.|National Institute of Optics and Photonics, Physics Institute of São Carlos, University of São Paulo, São Carlos, SP, 13560-970, Brazil. albp@ufba.br.|Center for Innovation, Technology and Education-CITE, Universidade Anhembi Morumbi-UAM, Parque Tecnológico de São José dos Campos, Estr. Dr. Altino Bondensan, 500, Eugênio de Melo, São José dos Campos, SP, 12247-016, Brazil. albp@ufba.br.
authors.forename: Antônio Luiz Barbosa
authors.initials: ALB
authors.lastname: Pinheiro
authors.affiliation: Center of Biophotonics, School of Dentistry, Federal University of Bahia-UFBA, Av. Araújo Pinho, 62, Canela, Salvador, BA, 40110-150, Brazil.
authors.forename: Luiz Guilherme Pinheiro
authors.initials: LGP
authors.lastname: Soares
authors.affiliation: Center of Biophotonics, School of Dentistry, Federal University of Bahia-UFBA, Av. Araújo Pinho, 62, Canela, Salvador, BA, 40110-150, Brazil.|National Institute of Optics and Photonics, Physics Institute of São Carlos, University of São Paulo, São Carlos, SP, 13560-970, Brazil.
authors.forename: Aparecida Maria Cordeiro
authors.initials: AMC
authors.lastname: Marques
authors.affiliation: Center of Biophotonics, School of Dentistry, Federal University of Bahia-UFBA, Av. Araújo Pinho, 62, Canela, Salvador, BA, 40110-150, Brazil.
authors.forename: Maria Cristina Teixeira
authors.initials: MCT
authors.lastname: Cangussú
authors.affiliation: Center for Innovation, Technology and Education-CITE, Universidade Anhembi Morumbi-UAM, Parque Tecnológico de São José dos Campos, Estr. Dr. Altino Bondensan, 500, Eugênio de Melo, São José dos Campos, SP, 12247-016, Brazil.
authors.forename: Marcos Tadeu Tavares
authors.initials: MTT
authors.lastname: Pacheco
authors.affiliation: Center for Innovation, Technology and Education-CITE, Universidade Anhembi Morumbi-UAM, Parque Tecnológico de São José dos Campos, Estr. Dr. Altino Bondensan, 500, Eugênio de Melo, São José dos Campos, SP, 12247-016, Brazil.
authors.forename: Landulfo
authors.initials: L
authors.lastname: Silveira
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology; D001842:Bone and Bones / Q000187:drug effects / Q000473:pathology* / Q000601:surgery*; D003094:Collagen / Q000494:pharmacology; D006882:Hydroxyapatites / Q000494:pharmacology*; D016014:Linear Models; D028022:Low-Level Light Therapy / Q000379:methods*; D008297:Male; D017208:Rats, Wistar; D013059:Spectrum Analysis, Raman / Q000379:methods*; D014945:Wound Healing / Q000187:drug effects*
chemical_list: D001672:Biocompatible Materials; D006882:Hydroxyapatites; C074950:hydroxyapatite-beta tricalcium phosphate; D003094:Collagen
keywords: Biochemical assay; Biomaterial; Bone repair; Laser and LED phototherapy; Raman spectroscopy