Introduction:
Low-level laser (LLL) is a special type of laser that tends to have a profound effect on biological systems. It is used more for therapeutic and research-based purposes currently in both medicine and dentistry through non-thermal means or mechanisms. The investigation into LLL was first initiated with the work of Mester et al in 1967. They were used for studying the impact of non-thermal effects of low-level lasers on hair growth in mice models.
According to Posten et al, the following should be the properties fulfilled or deemed to be considered as low-level laser therapy. These criteria are:
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The power output of lasers should range between 0.001 to 0.1 Watts.
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The wavelength of the laser should be in the range of 300 to 10,600 nanometers.
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The pulse rate should begin from zero, meaning it is almost continuous up to around 5000 Hertz per cycle per second.
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The intensity of LLL should be between 0.06 to 64.51 Watts per centimeter square and the dose of application should be between 0.01 to 100 Joule per centimeters square.
Based on the above criteria LLLT (low-level laser therapy) can be called lasers to a biologic system. These are initiated or performed by a medical or dental operator either to promote tissue regeneration or reduce the local inflammation in and around a lesion. Unlike many other common medical laser procedures, low-level laser therapy (LLLT) does not rely on ablative or thermal mechanisms to achieve its effects. Instead, LLLT utilizes a unique photochemical effect by absorbing light and inducing chemical changes in the targeted area. This makes it a distinct and effective treatment option for pain relief and various medical conditions.
The main rationale behind the colloquial reference to the LLL technique as low-level laser therapy in the field of medicine is the notably reduced energy density levels in comparison to other forms of medical laser therapy such as dental or surgical laser therapies, which are typically employed for tissue ablation (removal of diseased tissue), tissue cutting, or tissue coagulation through thermal means. Conversely, the LLL technique is distinguished by its exclusive focus on tissue regeneration, inflammation alleviation, and pain control using non-thermal modalities.
What Are the Effects of LLLT on Tissues?
Current dental research investigated the mechanism of LLLTs that involve the mitochondria in the cell membranes. Cytochrome c oxidase (COX) is the first to be noted as a membrane protein with a specific heme-based binuclear center called a3-CuB, which can aid in the transfer of electrons from water-soluble cytochrome c oxidase to oxygen. This membrane protein is rather the final or terminal enzyme in the electron transport chain reaction and plays one of the key roles in the bioenergetics of body cells with the COX2 having a primary role in causing pain (by converting arachidonic acid into inflammatory prostaglandins causing pain). LLLT effectively regulates or acts as a potent inhibitor of this pathway.
Current dental research shows the molecular and cellular mechanisms of LLLT. According to which photons or light energy particles that are absorbed by the mitochondria can stimulate more cellular energy or ATP production and lower levels of reactive oxygen species (ROS). Thereby reducing cell stress and activating transcription factors, such as NF-κB, induce gene transcript changes that can be the main beneficial mechanism of action of LLLT in preventing edema or swelling.
Low-level lasers have been currently extensively researched by dental researchers on their biological impact on the oral mucous membranes. Not only can its nonthermal effects promote oral healing, but it can also alleviate dental soft tissue or oral pain in dental patients, and promote oral cells. Immunity through the repair of cell membranes also accelerates oral wounds to heal faster. Wavelengths of approximately 670 to 700 nanometers are used when LLLT is done in a clinical or hospital setting for common periodontal surgeries.
The low-level laser’s anti-inflammatory effect would be mainly because of its regulation or regulatory mechanism of the pathways or expressions of COX2, as elaborated above.
What Are the Applications of LLLT in Pain Management?
After dental surgery, post-operative pain is the major complaint for many dental cases owing to the tissue trauma that would be because of the dental or maxillofacial surgical instrumentation and the subsequent release of inflammatory mediators in this surgically treated area in question. Further, this pain may be attaining a peak or of maximum discomfiture orally to the patient, when the local or general anesthetic effects after the dental or maxillofacial surgery begin to wear off. Low-level lasers have been studied and investigated extensively for their modern-day implementation as effective pain-control measures which score a higher benefit over conventional oral painkillers that are prescribed by your dentist post-operatively.
Yet again, this effect would be attributed to the anti-inflammatory effect exerted by low-level laser therapy due to COX2 pathway regulation. Further with its potency to fasten the surgical wound healing.
What Are the Applications of LLLT in Periodontal Surgeries?
Low-level laser therapies can be utilized in periodontal surgery in versatile ways by the dental operator or the maxillofacial surgeon for specific purposes like as accelerating or improving the healing time in procedures like gingivectomy (removal of inflamed gingiva) or coronally advanced flap surgeries (flap surgery of gingiva), in the elimination of supra bony periodontal pockets, or even for reducing the post-operative pain or edema or swelling that occurs after free gingival graft surgery or bone augmentation (surgery for increasing bone height) surgeries in the jaw. Recent studies in dentistry suggest that low-level lasers are gradually becoming part of contemporary periodontal care pain management strategies, particularly as a post-operative intervention due to their effectiveness in promoting the healing of gum and periodontal tissues, when compared to traditional oral COX2 inhibitors or pain medications. In procedures such as implant placements and maxillofacial surgeries, utilizing LLLT or low-level laser therapy can offer various advantages for monitoring patients and managing pain and swelling resulting from surgical tissue damage.
Conclusion:
The biological impact of low-level laser therapies that have been researched extensively on dental tissues, especially the gingival and periodontal tissues, and their ease of use by the dental surgeon, periodontist, or maxillofacial surgeon in procedures ranging from gingivectomy to free grafts, augmentation surgeries and in postoperative pain control. These are indeed aimed at alleviating and improving the post-surgical outcomes in dental cases.
