title: The efficacy of low-level 940 nm laser therapy with different energy intensities on bone healing.
abstract: The aim of this study was to evaluate the efficacy of low-level 940 nm laser therapy with energy intensities of 5, 10 and 20 J/cm2 on bone healing in an animal model. A total of 48 female adult Wistar rats underwent surgery to create bone defects in the right tibias. Low-level laser therapy (LLLT) was applied immediately after surgery and on post-operative days 2, 4, 6, 8, 10 and 12 in three study groups with energy intensities of 5 J/cm2, 10 J/cm2 and 20 J/cm2 using a 940 nm Gallium-Aluminium-Arsenide (Ga-Al-As) laser, while one control group underwent only the tibia defect surgery. All animals were sacrificed 4 or 8 weeks post-surgery. Fibroblasts, osteoblasts, osteocytes, osteoclasts and newly formed vessels were evaluated by a histological examination. No significant change was observed in the number of osteocytes, osteoblasts, osteoclasts and newly formed vessels at either time period across all laser groups. Although LLLT with the 10 J/cm2 energy density increased fibroblast activity at the 4th week in comparison with the 5 and 20 J/cm2 groups, no significant change was observed between the laser groups and the control group. These results indicate that low-level 940 nm laser with different energy intensities may not have marked effects on the bone healing process in both phases of bone formation.
authors.affiliation: Karadeniz Technical University, Faculty of Dentistry, Department of Oral and Maxillofacial Surgery, Trabzon, Turkey.
authors.forename: Kerem Turgut
authors.initials: KT
authors.lastname: Atasoy
authors.affiliation: Karadeniz Technical University, Faculty of Dentistry, Department of Oral and Maxillofacial Surgery, Trabzon, Turkey.
authors.forename: Yavuz Tolga
authors.initials: YT
authors.lastname: Korkmaz
authors.affiliation: Karadeniz Technical University, Faculty of Medicine, Department of Histology and Embriology, Trabzon, Turkey.
authors.forename: Ersan
authors.initials: E
authors.lastname: Odaci
authors.affiliation: Karadeniz Technical University, Faculty of Medicine, Department of Histology and Embriology, Trabzon, Turkey.
authors.forename: Hatice
authors.initials: H
authors.lastname: Hanci
mesh_terms: D000818:Animals; D001861:Bone Regeneration / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005347:Fibroblasts / Q000528:radiation effects; D054023:Lasers, Semiconductor / Q000627:therapeutic use*; D028022:Low-Level Light Therapy / Q000379:methods*; D010006:Osteoblasts / Q000528:radiation effects; D010010:Osteoclasts / Q000528:radiation effects; D010012:Osteogenesis / Q000528:radiation effects; D017208:Rats, Wistar; D012016:Reference Values; D015203:Reproducibility of Results; D013977:Tibia / Q000473:pathology / Q000528:radiation effects; D013997:Time Factors; D016896:Treatment Outcome; D014945:Wound Healing / Q000528:radiation effects*