RESUMO
OBJECTIVE: To determine the transmittance spectrum of primary dressings commonly used in the treatment of cutaneous wounds to verify if there is a real need to remove them during photobiomodulation. METHODS: Spectroscopic analysis was performed on 17 dressings using a spectrophotometer (USB 2000+; OceanOptics, Delray Beach, Florida). A piece of each dressing was inserted into a quartz cuvette; the reflection from the slide walls was corrected for using a 0.9% saline solution to completely fill the cuvette (baseline). The transmittance of each dressing was measured between 350 and 950 nm, and a transmittance table was created based on the main wavelengths used in photobiomodulation. RESULTS: Six dressings (Supriderme, Membracel, Cuticell Contact, UrgoTul, Tegaderm, and Opsite Flexigrid) have a transmittance greater than 50% in most of the spectral range and therefore may remain on wounds during irradiation. CONCLUSIONS: It may not always be necessary to remove a primary dressing when lasers or LED lights are used to treat wounds. It is the authors' hope that the results of this article will increase the effectiveness of both photobiomodulation and primary dressings and reduce patient discomfort as well as the cost of primary dressings via a reduction in unnecessary dressing changes.