Int J Med Sci 2012; 9(10):853-861. doi:10.7150/ijms.4440 This issue

Research Paper

Effect of Low-Level Laser Therapy on Incorporation of Block Allografts

Renato Valiati1,2✉, Jefferson Viapiana Paes1,2, Aury Nunes de Moraes3, Aldo Gava3, Michelle Agostini1, Anelise Viapiana Masiero1, Marilia Gerhardt de Oliveira4, Rogério Miranda Pagnoncelli5

1. School of Dentistry, Universidade do Planalto Catarinense (UNIPLAC), Lages, Brazil;
2. School of Dentistry, Pontifícia Universidade Católica do Rio Grande do Sul (PUC-RS), Porto Alegre, Brazil;
3. Universidade do Estado de Santa Catarina (UDESC), Lages, Brazil;
4. Oral and maxillofacial surgery department, PUC-RS, Porto Alegre, Brazil;
5. Dental surgery department, PUC-RS, Porto Alegre, Brazil.

This is an open access article distributed under the terms of the Creative Commons Attribution (CC BY-NC) License. See for full terms and conditions.
Valiati R, Paes JV, de Moraes AN, Gava A, Agostini M, Masiero AV, de Oliveira MG, Pagnoncelli RM. Effect of Low-Level Laser Therapy on Incorporation of Block Allografts. Int J Med Sci 2012; 9(10):853-861. doi:10.7150/ijms.4440. Available from

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Objective To assess the effect of low-level laser therapy (LLLT) on the incorporation of deep-frozen block allografts in a rabbit model.

Background Data Studies have shown that LLLT has beneficial effects on tissue repair and new bone formation.

Methods Bone tissue was harvested from two rabbits, processed by deep-freezing and grafted into the calvaria of 12 animals, which were then randomly allocated into two groups: experimental (L) and control (C). Rabbits in group L were irradiated with an aluminum gallium arsenide diode laser (AlGaAs; wavelength 830 nm, 4 J/cm2), applied to four sites on the calvaria, for a total dose of 16 J/cm2 per session. The total treatment dose after eight sessions was 128 J/cm2. Animals were euthanized at 35 (n = 6) or 70 days (n = 6) postoperatively.

Results Deep-freeze-processed block allografts followed by LLLT showed incorporation at the graft-host interface, moderate bone remodeling, partial filling of osteocyte lacunae, less inflammatory infiltrate in the early postoperative period, and higher collagen deposition than the control group.

Conclusion Optical microscopy and scanning electron microscopy showed that allograft bone processed by deep-freezing plus LLLT is suitable as an alternative for the treatment of bone defects. Use of the deep-freezing method for processing of bone grafts preserves the structural and osteoconductive characteristics of bone tissue.

Keywords: Bone healing, Diode/diode laser, Effect of lasers in tissue, Low-level laser therapy.