INTRODUCTION: Low-level laser therapy is becoming more popular and there is a growing interest in its effects, as reflected in the increased number of articles published about the subject. Many therapists and researchers have used a laser dose definition based on energy density (deltaE). However, the variety of laser equipments may lead to differences in the therapeutic results found, since the parameters supplied by these equipments vary according to the manufacturer. OBJECTIVE: To analyze the final energy transmitted to the tissue when applying the same deltaE using equipment of different Brazilian brands. MATERIAL AND METHODS: Seven brands of Brazilian equipment with different mean power (Pm) were evaluated by means of simulations. deltaE of 1J/cm² was applied using each brand of equipment, in order to evaluate possible differences in the final energy. RESULTS: The same deltaE applied using different brands of Brazilian equipment supplied final energy that ranged from 10 to 90mJ. This variation in the energy was mainly due to differences in Pm. These values ranged between 5.4 and 75mW. CONCLUSIONS: This variability in the final energy that is transmitted to the tissue indicates that deltaE may not be the best parameter for describing the dose to be used. In addition to deltaE, the final energy needs also to be stated, in order to establish the dose for obtaining the best therapeutic results.
low-level laser therapy; dose; parameters
