The Use of Low-Level Energy Laser Radiation in Basic and Clinical Research

Abstract

Laser radiation has specific attributes: monochromaticity, high coherence and polarization. These properties result in the extensive use of lasers in medicine. Laser devices can be assigned into three basic groups by means of their level of energy: high, medium and low energy. All of these types of radiation are used in medicine. However, the most commonly used, in basic science and clinical studies, is low-energy radiation. Molecular effects of low energy laser irradiation on cells are generally described as "fotobiostimulation" and "fotobiomodulation". These phenomena consequently lead to attempts to exploit this kind of radiation as a treatment method (low-level laser therapy-LLLT). Areas in which LLLT is used are: regenerative medicine (for healing wounds and ulcers); aesthetic medicine (to improve appearance of scars); dentistry (to accelerate healing of implants); physiotherapy (to reduce chronic pain syndromes), orthopedics (in bone healing) and cardiology (as a prevention of restenosis after percutaneous coronary intervention). This paper discusses the medical applications of LLLT which are used in daily clinical practice as well as those The laser was invented by Theodor Maiman in 1960 and since that time it is used in many different aspects of human life, including medicine. Lasers are distinguished from other light sources by their coherence, polarization and monochromaticity; therefore, they can transmit a wide range of energy.The physical process enabling the laser to function is called stimulated emission (laser is an acronym of light amplification by stimulated emission of radiation). There are many ways to classify laser devices. Lasers can be grouped by gain medium, wavelengths, modes of operation but the most useful way, from a medical point of view, is the division by energy level. And so by the amount of energy transmitted, the sources of laser radiation are divided into 3 basic groups: low, medium and high energy.There are many reports regarding the usefulness of full laser energy spectrum in clinical practice. High-energy radiation causes tissue destruction and therefore it is mainly applied in surgery. It is used for coagulation, cutting tissue, control of bleeding, destruction of tumors etc. Medium energy lasers are mainly used in oncology, especially as a part of photodynamic therapy. The low energy laser, among the all energy radiation groups, seems to have the widest range of applications in medicine. Despite much research, the exact mechanism action of low energy laser radiation on the human body is still unknown. Due to numerous studies on low-energy radiation, new therapeutic applications are being discovered and enrolled to clinical practice. The aim of this paper is to review the most common clinical applications of low-energy lasers.

Low level laser therapy reduces acute lung inflammation without impairing lung function

“…The use of low‐level laser therapy (LLLT) as a therapeutic tool was first described almost 50 years ago . Since then LLLT has been proven to be a treatment that is effective and with few colateral effects compared to other therapies prescribed for inflammatory and traumatic disorders . However, even after decades of continuous research, the exact mechanisms of low energy laser radiation action on the human body is still unknown.…”

“…These effects on intracellular signaling may lead to various biological effects, demonstrated both on experimental models and on clinical trials .…”

Improvement of bone repair in diabetic rats subjected to ƛ780 nm low-level laser therapy

“…Previous studies have demonstrated the beneficial effects of LLLT on bone repair in experimental models of DM 12,13 . However, many other controversial data have been reported in the literature concerning the modulatory effect of LLLT on bone healing in diabetic animals, likely as a result of the variety of threshold parameters for energy density and intensity, including the irradiation time and the irradiation mode, used in the experiments 14,15 . Therefore, the purpose of this study was to assess the effect of a protocol of low-level laser therapy using diode GaAlAs laser on the bone repair in alloxan-induced diabetic rats.…”

High Power Laser and Photobiomodulation in Oral Surgery: Case Report

“…The use of low-level laser (photobiomodulation therapy) after surgery is a safe and effective treatment that allows a good healing process, reduces inflammation and guarantees analgesia. 21,22 There is also the possibility to apply a cooling system such as hydrogel to avoid erythema and pain caused by heat exposure. 23 Thus, to perform the laser frenectomy, the anesthetic technique does not differ from that performed for resection with a cold-scalpel, although the amount of anesthetic salt required is lower.…”