Computerized morphometric assessment of the effect of low-level laser therapy on bone repair: an experimental animal study.
OBJECTIVE
The aim of this study was to evaluate morphometrically the amount of newly formed bone after GaAlAs laser irradiation of surgical wounds created in the femur of rats.


BACKGROUND
Low-level laser therapy (LLLT) has been used in several medical specialties because of its biomodulatory effects on different biological tissues. However, LLLT is still controversial because of contradictory reports. This is a direct result of the different methodologies used in these works.


METHODS
In this study, 40 Wistar rats were divided into four groups of 10 animals each: group A (12 sessions, 4.8 J/cm2 per session, observation time of 28 days); group C (three sessions, 4.8 J/cm2 per session, observation time of 7 days). Groups B and D acted as nonirradiated controls. The specimens were routinely processed to wax and cut at 6-microm thickness and stained with H&E. For computerized morphometry, Imagelab software was used.


RESULTS
Computerized morphometry showed a significant difference between the areas of mineralized bone in groups C and D (p = 0.017). There was no difference between groups A and B (28 days; p = 0.383).


CONCLUSIONS
It is concluded that, under this experimental condition, LLLT increased bone repair at early bone healing.
Silva Júnior
Aurelício N
AN
School of Dentistry, Postgraduate Programe on Oral and Maxillofacial Surgery, Pontifícia Universidade Católica do Rico Grande do Sul, Porto Alegre, Brazil.
Pinheiro
Antonio L B
AL
Oliveira
Marília G
MG
Weismann
Ruben
R
Ramalho
Luciana Maria Pedreira
LM
Nicolau
Renata Amadei
RA
D000818:Animals; D001842:Bone and Bones / Q000528:radiation effects*; D002113:Calcification, Physiologic; D005260:Female; D007091:Image Processing, Computer-Assisted; D053685:Laser Therapy; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D014945:Wound Healing / Q000528:radiation effects*