Application of Low-Level Laser Irradiation (LLLI) and rhBMP-2 in Critical Bone Defect of Ovariectomized Rats: Histomorphometric Evaluation

Author(s)

Siessere, Selma ^[1] ; de Sousa, Luiz Gustavo ^[1] ; Mardegan Issa, Joao Paulo ^[1] ; Iyomasa, Mamie Mizusaki ^[1] ; Pitol, Dimitrius Leonardo ^[1] ; Amorim Barbosa, Ana Paula ^[1] ; Semprini, Marisa ^[1] ; Sebald, Walter ^[2] ; Badra Bentley, Maria Vitoria ^[3] ; Hallak Regalo, Simone Cecilio ^[1]

Affiliation

^[1] Univ Sao Paulo, Fac Dent, BR-14040904 Sao Paulo - Brazil

^[2] Univ Wurzburg, Theodor Boveri Inst Biowissensch, Wurzburg - Germany

^[3] Univ Sao Paulo, Fac Pharmaceut Sci Ribeirao Preto, BR-14040904 Sao Paulo - Brazil

• Document type: Journal article
• Source: Photomedicine and Laser Surgery; v. 29, n. 7, p. 453-458, JUL 2011.
• Web of Science Citations: 7

Abstract

Objectives: The aim of this study was to evaluate the osteogenic potential of recombinant human bone morphogenetic protein-2 (rhBMP-2) and low-level laser irradiation (LLLI), isolated or combined in critical bone defects (5mm) in parietal bone using ovariectomized female rats as an experimental animal model. Materials and Methods: Forty-nine female Wistar rats, bilaterally ovariectomized (OVX), were divided into seven treatment groups of seven animals each: (I) laser in a single application, (II) 7 mu g of pure rhBMP-2, (III) laser and 7 mu g of pure rhBMP-2, (IV) 7 mu g of rhBMP-2/monoolein gel, (V) laser and 7 mu g of rhBMP-2/monoolein gel, (VI) laser and pure monoolein gel, and (VII) critical bone defect controls. The low-level laser source used was a gallium aluminum arsenide semiconductor diode laser device (lambda = 780 nm, D = 120 J/cm(2)). Results: Groups II and III presented higher levels of newly formed bone than all other groups with levels of 40.57% and 40.39%, respectively (p < 0.05). The levels of newly formed bone of groups I, IV, V, and VI were similar with levels of 29.67%, 25.75%, 27.75%, and 30.64%, respectively (p > 0.05). The area of new bone formation in group VII was 20.96%, which is significantly lower than groups I, II, III, and VI. Conclusions: It was concluded that pure rhBMP-2 and a single dose of laser application stimulated new bone formation, but the new bone formation area was significantly increased when only rhBMP-2 was used. Additionally, the laser application in combination with other treatments did not influence the bone formation area. (AU)