Low Level Laser Therapy (LLLT) Mechanism of Action, Application and Laser Light Therapy Devices In Physical Therapy

Ahed Osama Ali (1) , Fatima Mohammed Shakhir Najm (2) , Zainab Emad Abd-ALKazem Muhammad (3) , Hadeer Hisham Ali (4) , Zahraa Alaa Fadl Allah Nahab (5)
(1) University of Babylon - College of Science for Women - Department of Laser Physics , Iran, Islamic Republic of
(2) University of Babylon - College of Science for Women - Department of Laser Physics , Iran, Islamic Republic of
(3) University of Babylon - College of Science for Women - Department of Laser Physics , Iran, Islamic Republic of
(4) University of Babylon - College of Science for Women - Department of Laser Physics , Iran, Islamic Republic of
(5) University of Babylon - College of Science for Women - Department of Laser Physics , Iran, Islamic Republic of


"Light Amplification by Stimulated Emission of Radiation" is what the acronym "laser" stands for. Various light sources, such as light-emitting diodes, have entered the laser arena. A wide variety of red and near-infrared light waves are employed. The target tissues are affected differently by each wavelength. Research on low-level laser treatment (LLLT) is booming as a potential solution to the problems caused by high-dose lasers. A variety of cells in the body are directly bio-stimulated by low-level laser therapy. It has been found that low-level laser therapy (LLLT) can speed up the healing process for wounds and also stimulate bone cells, which means that bones can recover more quickly.

Stimulated emission of radiation is the process that produces laser light. Laser light has numerous distinguishing features, including great intensity, homogeneity, and the fact that it travels in a straight line, all of which contribute to its targeted interactions with biological tissues. Presenting a wide range of laser applications in pharmacy and medicine, this study also aims to describe the fundamentals of lasers and how they interact with tissues. The biostimulation effects of low-level laser therapy include an elevated core body temperature, enhanced blood circulation, and accelerated metabolic rate. Treatment with high-powered lasers causes photothermal effects. This tissue undergoes fotoablation and fotocoagulation when exposed to that particular wavelength of laser light. Lasers can be either continuously operating or releasing light pulses at a specific frequency. The laser's active centre can be made of a variety of materials, including solids, liquids, semiconductors, or gases. The medical and pharmaceutical fields are well-known for their extensive use of lasers. Many medical fields make use of lasers, including dermatology, ophthalmology, stomatology, laryngology, and neurology, due to their ability to reduce bleeding, make precise cuts, ensure improved visibility during operations, lessen pain, and speed up the healing process after injuries. The impact of laser biostimulation on the efficacy of pharmaceutical treatments.

A relatively new method for wound healing is low level laser therapy (LLLT). Current approaches for treating wounds with laser radiation and clinical concerns for various wound types are reviewed in this paper. We also quickly go over the hypothesised ways in which LLLT aids in the healing of wounds. Additional controlled trials are required to clarify the many stages of the healing process and objectively determine the influential parameters of LLLT, while numerous studies have improved our understanding of the laser healing process.

The effects of LLLT are still up for debate, despite numerous reports of positive results from in vitro studies, animal models, and randomised controlled human trials. Contrarily, more studies are required to determine whether periodontal therapy is effective.

Full text article

Generated from XML file


Kato K, Shinzawa K, Yoshikawa S. Cytochrome oxidase is a possible photoreceptor in mitochondria. Photobiochem Photobiophys 1981 Jan;2:263-269.

Dourado DM, Fávero S, Matias R, de Tarso P, Carvalho C, da Cruz-Hofling MA. Low-level laser therapy promotes vascular endothelial growth factor receptor-1 expression in endothelial and nonendothelial cells of mice gastrocnemius exposed to snake venom. Photochem Photobiol 2011 Mar- Apr;87(2):418-426.

Cury V, Moretti AIS, Assis L, Bossini P, Crusca JS, Neto CB, Fangel R, de Souza HP, Hamblin MR, Parizotto NA. Low level laser therapy increases angiogenesis in a model of ischemic skin flap in rats mediated by VEGF, HIF-1a and MMP-2. Photochem Photobiol 2013;125:164-170.

Asimova M, Thanh NC. Laser induced photodissociation of oxyhemoglobin: optical method of elimination of hypoxia (oxygen deficiency in biotissue). Opt Spectrosc 2011 Aug;111(2): 224-229.

Heu F, Forster C, Namer B, Dragu A, Lang W. Effect of low-level laser therapy on blood flow and oxygen- haemoglobin saturation of the foot skin in healthy subjects: a pilot study. Laser Therapy 2013;22(1):21-30.

Carrera M, Pereiraa MC, Bacellar de Pinho C, Medradoa ARP, de Araújo Andradec Z, de Almeida Reis SR. Influence of 670 nm low-level laser therapy on mast cells and vascular response of cutaneous injuries. J Photochem Photobiol B: Biology 2010;98:188-192.

Mi XQ, Chen JY, Zhou LW. Effect of low power laser irradiation on disconnecting the membrane-attached haemoglobin from erythrocyte membrane. J Photochem Photobiol B: Biology 2006;83:146-150.

Kreisler M, Christoffers AB, Al Haj H, Willershausen B, d’Hoedt B: Low level 809-nm diode laser-induced in vitro stimulation of the proliferation of human gingival fibroblasts. Lasers Surg Med 2002;30(5):365-369.

Yu W, Naim JO, McGowan M, Ippolito K, Lamafame RJ. Photomodulation of Oxidative Metabolism and Electron Chain Enzymes in Rat Liver Mitochondria. Photochem Photobiol 1997;66(6):866-871.

Akgul T, Gulsoy M, Gulcur HO. Effects of early and delayed laser application on nerve regeneration. Lasers Med Sci 2014; 29:351-357.

Farouk AH, Al-Watban FAH, Zhang XY, Bernard L. Andres. Photomed Laser Surg 2007; 25(2):72-77.

Babu B, Uppada UK, Tarakji B, Hussain KA, Azzeghaibi SN, Alzoghaibi I. Versatility of diode lasers in low-level laser therapy for the management of recurrent aphthous stomatitis. J Orofac Sci 2015;7:49-53.

Agrawal H, Singh MP, Nahar P, Mathur H, Gv S. Efficacy of lowlevel laser therapy in treatment of recurrent aphthous ulcers: a sham controlled, split mouth follow up study. J Clin Diagn Res 2014;8:218-221.

Aykol G, Baser U, Maden I, Kazak Z, Onan U, Tanrikulu- Kucuk S, Ademoglu E, Issever H, Yalcin F. The Effect of Low-Level Laser Therapy as an Adjunct to Non-Surgical Periodontal Treatment. J Periodontol 2011;82:481-488.

Amorim JC, de Sousa GR, de Barros Silveira L, Prates RA, Pinotti M, Ribeiro MS. Clinical study of the gingiva healing after gingivectomy and low-level laser therapy. Photomed Laser Surg 2006;24:588-594.

Ozcelik O, Cenk Haytac M, Kunin A, Seydaoglu G. Improved wound healing by low-level laser irradiation after gingivectomy operations: a controlled clinical pilot study. J Clin Periodontol 2008;35:250-254.

Sanz-Moliner JD, Nart J, Cohen RE, Ciancio SG. The effect of an 810-nm diode laser on postoperative pain and tissue response after modified Widman flap surgery: a pilot study in humans. J Periodontol 2013;84:152-158.

Fikácková H1, Dostálová T, Navrátil L, Klaschka J. Effectiveness of low-level laser therapy in temporomandibular joint disorders: a placebo-controlled study. Photomed Laser Surg 2007 Aug;25(4):297-303.

Green JB, Metelitsa AI. Optimizing outcomes of laser tattoo removal. Skin Therapy Lett.; 16(10):1-3 (2011).

Hawkins D, Houreld N, Abrahamse H. Low level laser therapy (LLLT) as an effective therapeutic modality for delayed wound healing. Annals of the New York Academy of Sciences.; 1056(1):486-93 (2005).

Calin MA, Coman T, Calin MR. The effect of low level laser therapy on surgical wound healing. Romanian Reports in Physics. 62(3):617-27 (2010).

Hamblin MR, Demidova TN, editors. Mechanisms of low level light therapy. Biomedical Optics 2006; International Society for Optics and Photonics (2006).

Yadollahpour A, Rezaee Z. Electroporation as a New Cancer Treatment Technique: A Review on the Mechanisms of Action. Biomedical & Pharmacology Journal.; 7(1):53-62 (2014).

Yadollahpour A, Rashidi S. Therapeutic Applications of Electromagnetic Fields in Musculoskeletal Disorders: A Review of Current Techniques and Mechanisms of Action. Biomedical and Pharmacology Journal.; 7(1):23-32 (2014).

Karu T. Photobiological fundamentals of lowpower laser therapy. Quantum Electronics, IEEE Journal of; 23(10):1703-17 (1987).

Baranoski S, Ayello EA. Wound care essentials: Practice principles: Lippincott Williams & Wilkins; (2008). 15. Lauchli S. [Alternative methods for wound treatment]. MMW Fortschritte der Medizin.; 149(46):41-2 (2007).

Randall P, Randall RJ. The effects of various methods of treatment on wound healing: an experimental study. Plastic and reconstructive surgery; 14(2):105-17 (1954). 17. Shal’nev AN. [New methods and means for local wound treatment]. Voenno-meditsinskii zhurnal. 9:72-3 (1985).

Szmyt K, Lukasz K, Bobkiewicz A, Cybulka B, Ledwosinski W, Gordon M, et al. Comparison of the effectiveness of the treatment using standard methods and negative pressure wound therapy (NPWT) in patients treated with open abdomen technique. Polski przeglad chirurgiczny; 87(1):22-30 (2015).

Seyer JM. A pentapeptide from type 1 procollagen promotes extracellular matrix production. J Biol Chem 1993; 268: 9941–4.

Furth JJ. The steady-state levels of type I collagen mRNA are reduced in senescent fibroblasts. J Gerontol 1991; 46: B122–4.

Glogau R. Topically applied botulinum toxin type A for the treatment of primary axillary hyperhidrosis: results of a randomized, blinded, vehicle controlled study. Dermatol Surg 2007; 33: s76–80.

Fisher GJ, Varani J, Voorhees JJ. Looking older: fibroblast collapse and therapeutic implications. Arch Dermatol 2008; 144: 666–72.


Ahed Osama Ali
imadbiotechnology@gmail.com (Primary Contact)
Fatima Mohammed Shakhir Najm
Zainab Emad Abd-ALKazem Muhammad
Hadeer Hisham Ali
Zahraa Alaa Fadl Allah Nahab
Ali, A. O., Shakhir Najm , F. M., Muhammad , Z. E. A.-A., Ali , H. H., & Allah Nahab , Z. A. F. (2024). Low Level Laser Therapy (LLLT) Mechanism of Action, Application and Laser Light Therapy Devices In Physical Therapy. Journal of Current Medical Research and Opinion, 7(06), 2757–2765. https://doi.org/10.52845/CMRO/2024/7-6-6

Article Details