For the past few decades, many studies have investigated the adjunctive use of high-intensity and low-level energy lasers in periodontal therapy. Although the beneficial use of diode-laser therapy in studies have not provided sufficient evidence to support its efficacy as an addition to treatment, the bactericidal and detoxifying effects of the diode laser during NSPT has been reported in several studies, and its ability to produce beneficial effects for reducing pain, promoting wound-healing and anti-inflammatory responses for the patient being treated for gingivitis or periodontal disease have also been duly noted.
The diode laser operates by a semiconductor embedded in a crystal and is meant for soft tissue use only.Although the biological effects of laser radiation on the oral tissues are still not completely understood, it has been suggested that low-level laser energy with diode lasers is responsible for promoting faster tissue repair and wound-healing, and should be noted for its bio-stimulatory effects.The effects of low-level laser energy on a cellular level are related to photochemical reactions within the cells, rather than through the thermal effects.
The diode laser, with a wavelength of 655 and 980, does not interact with dental hard tissues. It is used for cutting and coagulating soft tissue, and has been proposed for sulcular debridement and curettage. Recent studies reported short-term microbiological effects with the use of diode laser therapy, as well as its acceptance by patients and overall safety. Using a diode laser also presents more ergonomic benefits for the operator (in this case, the dental hygienist).
More than 1,000 different species of anaerobic microorganisms have been found in the oral cavity, and the majority of these are attached to any available surface forming biofilms. In addition to the oral infections caused by biofilm bacteria, these pathogens also represent a threat for systemic infections as found in infective endocarditis. Most cases of infective endocarditis are caused by daily brushing and flossing, not by invasive procedures; this makes eradication of anaerobic microorganism during SPR vital in assisting patients to maintain a healthy environment in their mouths in order to help their hearts.
The diode laser’s anti-inflammatory effects from irradiating P. gingivalis can relieve cellular stress, decrease the release of pro-inflammatory cytokines, and mitigate inflammation after treatment. The laser not only diminishes bacteria, but can also aid in reducing gingival overgrowth.
Wound healing and tissue regeneration is another specialty of the diode laser. Research shows that with high-frequency, low-level diode treatments, the proliferation and migration rate of human gingival epithelial cells (HGEC) were markedly increased in the first few hours after treatment.Additionally, periodontal ligament fibroblasts (PDLF) were shown to have significant incremental proliferation in the first 24 to 48 hours, but leveled off at the 72-hour mark.This is beneficial during the wound-healing process in healing by primary intention to create a shorter junctional-epithelium and cause less apical migration.
Not only does the diode laser affect PDLF in a positive manner, it also affects stem cells. Stem cells taken from the pulp of a permanent tooth were shown to be able to differentiate into osteoblasts, fibroblasts, and cementoblasts: all periodontal tissues needed for dental wound repair. When placed under a microscope after diode laser treatment, there was increased cell proliferation in fibroblasts, endothelial cells, osteoblasts, epithelial cells, and lymphocytes. There is also evidence of mesenchyme, bone marrow, and adipose tissue stem cell proliferation, but they were not the focus of the study.
When a diode laser with appropriate wavelength irradiates a targeted site, the energy is then absorbed and produces heat. The diode laser has been used to irradiate at the lowest output level possible without interfering with its functionality within each clinical trial.
Clinical research studies noted these errors: not giving consideration that certain health hazards could have a significant negative effect on the end results, such as smokers (tobacco), drinkers (alcohol), or drug users (legally prescribed, or street-illegal). Those diagnosed with a systemic illness, or those who are immunocompromised, have an increased negative effect on the treatment due to slowed or debilitated healing abilities and the increased risk of infection; in addition to which SRP was conducted in both the control groups and the test groups in all the reviewed research-studies shared within this review leading to the probability that SRP may have masked the adjunctive benefit of PAD’s (photo-activated disinfectant) LED (light-emitting diode).
Reviews and clinical studies conducted with SRP alone compared to SRP with DL show that multiple factors could compromise periodontal therapy.
Another form of possible clinical error arises from the research studies conducted in a split-mouth environment. This is primarily due to the likelihood of cross-contamination within each subject’s mouth.
In conclusion, the diode laser used in conjunction with SRP enhances wound healing, decreases gingival bleeding, inflammation, and pocket depths, reduces bacterial populations at the surgical site, and leads to faster healing and less post-operative pain.It has been proven that SPR and laser therapy were better for the patients than just SPR alone, and its effects are evident up to six weeks after therapy.
Laser therapy should be used as an adjunct to therapy and not to replace mechanical intervention.
Vanessa Pavicic and Heidi Weber recently graduated from the dental hygiene program at Collin College in McKinney, Texas.