980-nm Diode Laser Research Articles

Evaluation of dentinal tubule occlusion and pulp tissue response after using 980-nm diode laser for dentin hypersensitivity treatment.

To evaluate the effectiveness of the 980-nm diode laser for dentinal tubule occlusion, measure the intrapulpal temperature, and investigate the dental pulp response. The dentinal samples were randomly divided into G1-G7 groups: control; 980-nm laser irradiation (0.5 W, 10s; 0.5 W, 10s × 2; 0.8 W, 10s; 0.8 W, 10s × 2; 1.0 W, 10s; 1.0 W, 10s × 2). The dentin discs were applied for laser irradiation and analyzed by scanning electron microscopy (SEM). The intrapulpal temperature was measured on the 1.0-mm and 2.0-mm thickness samples, and then divided into G2-G7 groups according to laser irradiation. Moreover, forty Sprague Dawley rats were randomly divided into the laser-irradiated group (euthanized at 1, 7, and 14days after irradiation) and the control group (non-irradiated). qRT-PCR, histomorphology, and immunohistochemistry analysis were employed to evaluate the response of dental pulp. SEM indicated the occluding ratio of dentinal tubules in the G5 (0.8 W, 10s × 2) and G7 (1.0 W, 10s × 2) were significantly higher than the other groups (p < 0.05). The maximum intrapulpal temperature rises in the G5 were lower than the standard line (5.5 ℃). qRT-PCR showed that the mRNA expression level of TNF-α and HSP-70 upregulated significantly at 1day (p < 0.05). Histomorphology and immunohistochemistry analysis showed that, compared with the control group, the inflammatory reaction was slightly higher at the 1 and 7days (p < 0.05) and decreased to the normal levels at 14days (p > 0.05). A 980-nm laser at a power of 0.8 W with 10s × 2 defines the best treatment for dentin hypersensitivity in terms of compromise between the efficacy of the treatment and the safety of the pulp. The 980-nm laser is an effective option for treating dentin sensitivity. However, we need to ensure the safety of the pulp during laser irradiation.

Endovenous Laser Ablation of Venous Ulcers of the Lower Limbs: A Study of the Relationship between Applied Laser Power and Age/Gender

Abstract Endovenous laser ablation therapy (EVLA) relies heavily on the power of the laser used. Therefore, the relationships between this power and other related parameters can be studied and taken into account in order to obtain successful results from the treatment. Not only the related parameters should be tested and examined, but some other parameters that may appear unrelated to the success of the EVLA treatment should also be studied in order to improve and succeed the venous treatment. Thus, the correlation coefficient between the applied laser power and age/gender was calculated in this study. The purpose of this study was to compare the laser power used in the EVLA procedure with age for the two genders. 42 patients who suffered from venous ulcers in the lower limbs of the human body were treated with a 1470-nm diode laser. So, the correlation coefficient was for males and for females.

Short- and mid-term results of diode laser treatment in pilonidal sinus disease and the role of endoscopic camera use on outcomes.

Nowadays, surgical treatment of pilonidal sinus disease (PSD) with novel techniques is a topic of interest since conventional methods are associated with longer return to daily life and higher complication and recurrence rates. Recently, use of laser as a minimally invasive approach has become popular in the surgical treatment of PSD. In this study, we analyze the short- and mid-term results after laser treatment and the effect of endoscopic camera use on outcomes. A total of 106 patients with PSD who underwent laser treatment between November 2017 and September 2021 were included in this study. All patients were treated with a 1470-nm diode laser. Endoscopic camera was used in 73 patients and results of these were compared with those in whom camera was not used. Follow-up period was determined as a minimum of 1year. Data were analyzed retrospectively. There were 80 (75%) male and 26 female patients. The median age was 26 (range 13-50) years. On the first postoperative day, 26 (26.5%) patients did not have any pain and 42(42.8%) patients reported low-grade pain. The mean time to return to daily life was 4.5 ± 5.5 (median 2, range 1-30) days. The complication rate was 10.4%. Eighty-six (87.8%) patients completely recovered and the mean complete recovery time was 27.4 ± 15.9days. The patient satisfaction rate was 99.0%. The recurrence rate was 11.0%. Neither history of previous surgery nor abscess was associated with recurrence. Use of an endoscopic camera had no effect on postoperative pain, complete recovery, complications, patient satisfaction, and recurrence (p < 0.05). Laser treatment for PSD is a promising approach with the advantages of less postoperative pain, early return to daily life, high patient satisfaction, and acceptable complication and recurrence rates. Nevertheless, further studies are needed to investigate the role of endoscopic camera use in this procedure since its possible advantages could not be clarified.

Effect of Photobiomodulation Therapy With an 810-nm Diode Laser on Pain Perception Associated With Dental Injections in Children: A Double-Blind Randomized Controlled Clinical Trial.

Introduction: This study investigated the photobiomodulation effect of an 810-nm diode laser in adjunction with topical anesthesia on pain perception during infiltration anesthesia of primary maxillary molars in children. Methods: This double-blind randomized controlled clinical trial was conducted on 64 children (aged 5-9 years) requiring extraction or stainless steel crown for their primary maxillary molars. The patients were randomly allocated into two groups (n=32) of laser and control. In the laser group, the injection site (buccal and palatal mucosa) was irradiated with an 810-nm laser (200 mW, 5.2 J/cm2) after 20% benzocaine topical anesthetic application, while the control group received a placebo laser following topical anesthesia. The pain intensity experienced by children during needle insertion into the buccal and palatal mucosa was determined using a visual analog scale (VAS) and modified behavioral pain scale (MBPS). Results: According to the results of the VAS and MBPS, no significant difference was detected in pain scores between the laser and control groups neither in the buccal nor in the palatal mucosa (P>0.05). Conclusion: Photobiomodulation therapy with an 810-nm laser with the current setting adjunct to topical anesthesia did not promote significant additional effects on the pain intensity.

Management of oral leukoplakia with an 808-nm high-power diode laser: a single-center experience.

High-power diode laser emerges as a promising approach to the treatment of oral leukoplakia (OL); however, its short- and long-term effects have been barely explored. This study evaluated the postoperative endpoints and the recurrence rate of high-power diode laser treatment in a well-defined series of patients with OL. A prospective analysis was performed on 22 individuals comprising 31 OL. The lesions were irradiated using the following protocol: Indium-Gallium-Arsenide diode laser, 808nm, continuous-wave mode, 1.5-2.0 W, 780.0 ± 225.1J, and 477.1 ± 131.8s. Postoperative pain was assessed with a visual analog scale at three endpoints. Clinical follow-up was performed on all patients and the Kaplan-Meier test was used to analyze the probability of recurrence. The series consisted mostly of women (72.7%) with a mean age of 62.8years. A single laser session was performed in 77.4% of cases. The median score on the scale that assessed pain on the 1st, 14th and 42nd postoperative day was 4, 1, and 0, respectively. The mean follow-up period per lesion was 28.6months (range: 2-53months). A complete response was observed in 93.5% of OL cases, while 6.5% had recurrence. The probability of recurrence at 39months was 6.7%. No patient experienced malignant transformation. High-power diode laser for the treatment of OL is safe and effective during the trans- and postoperative period. These findings represent an alternative approach to the management of OL, mainly because a low recurrence rate was observed.

Combined use of a 980‑nm diode laser and preoperative intravesical instillation of pirarubicin for the prevention of short‑term recurrence of non‑muscle invasive bladder cancer: A pilot study.

At present, transurethral resection of bladder tumors (TURBT) is the main surgical method for treating non-muscle invasive bladder cancer (NMIBC), but its postoperative recurrence needs to be prevented. The aim of the present study was to investigate the efficacy of a 980-nm diode laser combined with preoperative intravesical instillation of pirarubicin (THP) for the prevention of NMIBC recurrence. The data of 120 patients with NMIBC who underwent transurethral resection between May 2021 and July 2022 were retrospectively collected, and these patients were followed up. The patients were divided into four groups based on the surgical method used and preoperative intravesical instillation of THP as follows: i) 980-nm diode laser with THP (LaT); ii) 980-nm diode laser alone (La); iii) TURBT with THP (TUT); and iv) TURBT alone (TU). Clinicopathological variables, postoperative complications and short-term outcomes among the aforementioned groups were analyzed. The blood loss volume and the incidence of perforation and delayed bleeding were significantly lower in the LaT and La groups compared with those in the TUT and TU groups. The days of bladder irrigation, catheter extubation and postoperative hospitalization were significantly shorter in the LaT and La groups compared with the TUT and TU groups. The detection rate of suspicious lesions was significantly higher in the THP irrigation groups (LaT and TUT) compared with that in the saline irrigation groups (La and TU). Tumor diameter and number, 980-nm laser and THP irrigation were shown to be independent risk factors in the Cox regression analysis. In addition, the recurrence-free survival (RFS) rate of the LaT group was significantly higher than that of the other three groups. In conclusion, a 980-nm diode laser can effectively reduce intraoperative blood loss and the incidence of perforation, and accelerate postoperative recovery. Preoperative intravesical instillation of THP is conducive to identifying suspicious lesions. The combination of a 980-nm laser with preoperative THP intravesical instillation can significantly prolong RFS time.

Effectiveness of 980nm diode Laser in reduction the diameters of exposed dentinal tubules for hypersensitive tooth

Abstracts: Background: The oral cavity is a complex environment, both structurally and functionally, the hard and soft tissues are in close a proximity. Oral tissues subjected to wear throughout the life, that threatened the vitality of the pulp or increase the sensitivity of dentinal tubules. One of the common dental problems is loss of enamel or cementum, which stimulate the nerve ending in or near the pulp and manifested as pain sensation. Aim of the study: This study had done to evaluate the effects of 980nm diode Laser in diameters reduction of exposed dentinal tubules analyze the results and morphological changes of irradiated dentine surface by FE-SEM (field emission scanning electron microscope) analysis. Material and Method: Thirty-nine human extracted impacted 3rd molar teeth were tested in this study and divided into control Group (N=15), pilot study (N=9) and study group (N=15). The study group irradiated with 980nm diode Laser to the occlusal surface of the teeth after the application of 17% EDTA (Ethelyn diamine tetra acetic acid) for smear layer removal. The intra-pulpal temperature recorded for every second and monitored for 120s from the first second of irradiation by a thermometer (prośket MT-1820, 1st Edition, 2016, Taiwan), for detection the recovery time of initial tooth temperature. FE-SEM analysis to all teeth (control, pilot and study groups) for assessment the morphological changes after surface irradiation. Results: FE-SEM analysis to the irradiated surface show significant reduction in diameters of the exposed dentinal tubules irradiated by 980nm diode Laser. Conclusion: The selected parameters (1.5W/10s, 276.3W/cm2) were able to seal exposed dentinal tubules without any sign of cracks or fissures. Suggestion: The parameters used with this study (1.5W, 10s, 276.3W/cm2) can be utilize in the future treatment protocol to the management of dentinal hypersensitivity.

High-Q lasing in Nd3+-doped phosphate glass microsphere resonators.

Nd3+-doped glasses are the most widely used laser gain media. However, Nd3+-doped non-silica microsphere lasers generally have lower quality (Q) factors due to the presence of non-radiative energy-loss impurities in traditional glass systems. In this work, we report the first, to the best of our knowledge, Nd3+-doped phosphate glass microsphere laser with the highest Q-factor of 1.54 × 106 among all Nd3+-doped non-silica glass microsphere lasers. Whispering gallery modes in the 1020-1120-nm band can be obtained for a typical microsphere with a diameter of 82.57 µm. When the pump power exceeds the threshold of 0.17 mW, single- and multi-mode microsphere lasing can be generated under 808-nm laser diode (LD) pumping. Typical Q-factors of the phosphate glass microspheres can reach 106, which is at least an order of magnitude higher than those of other Nd3+-doped non-silica glass microsphere lasers. The Nd3+-doped phosphate glass microsphere laser reported in this work can be considered as an active optical/photonic device with low pump thresholds.

Treatment and Prevention of Umbilical Sagging with Laser-assisted Liposuction: The New Happy Protocol.

Sagging of the periumbilical skin, also known as the "sad umbilicus," is one of the most common postoperative complications in liposuction. It is characterized by an increase in the width and decrease in the height of the umbilicus. Technological advances in power-assisted liposuction resulting in skin tightening have been central to improvements in the treatment of sagging skin. Laser-assisted liposuction is a procedure in which a laser fiber induces lipolysis and skin tightening. Laser treatment delivered using a 980-nm diode laser may result in up to 30% skin surface area contraction. The aim of this study was to describe a new technique called the "happy protocol" for the treatment and prevention of the sad umbilicus. The periumbilical region is treated using a 980-nm diode laser set to an output power of 20 W, with a total delivered energy of 5000 J. The developed technique may be applied to correct shape distortions or to create a natural-looking and aesthetically pleasant umbilicus during liposuction. A decrease in the width of the umbilicus followed by an increase in height are observed in the first postoperative days. Patients who were followed up for 7 months postoperatively showed positive aesthetic results. The final outcome was an oval-shaped umbilicus, with increased height and reduced sagging in the periumbilical region.

The 980-nm diode laser treatment for oral venous lakes: report of a series of 11 cases

The 980-nm diode laser treatment for oral venous lakes: report of a series of 11 cases

Implant Surface Topography Following Different Laser Treatments: An In Vitro Study.

Background Although dental implants have demonstrated very high success rates, they are susceptible to complications such as peri-implantitis that can lead to failure. Methods Twenty implants with surfaces grit-blasted using hydroxyapatite and acid-etched were randomly divided into four groups (five in each group). Three groups were assigned to laser treatments: Group I (erbium, chromium-doped: yttrium, scandium, gallium, and garnet (Er,Cr:YSGG) laser), Group II (650-nm diode laser), and Group III (808-nm diode), and one control group, Group IV. The surface roughness parameters (roughness average(Ra) and root mean square roughness(Rq)) were measured using a non-contact optical profilometer and scanning electron microscope to evaluate the surface topography after the laser treatments. Results Significant differences were observed between thelaser groups regarding the surface roughness Ra (3.56±0.26, 3.45±0.19, 3.77±0.42, pc=0.0004, pe=0.0002, pf=0.001) and Rq values (4.49±0.34, 4.35±0.26, 4.72±0.56, pc=0.0007, pe=0.0006, pf=0.002) and the control group(2.81±0.10; 3.57±0.19). However, no significant difference was observed between the different laser treatment modalities. The scanning electron microscope images revealed some morphological changes on the implant surfaces following laser treatment, but no melted morphology was observed. Conclusions The application of Er,Cr:YSGG, 650-nm diode laser, and 808-nm diode did not show melting changes on implant topography. However, some increase in surface roughness was detected. Further studies are recommended to assess the effectiveness of these laser settings onbacterial reduction and osseointegration.

Efficacy of 5.25% Sodium hypochlorite and 810 diode laser in reduction of microbial count in root canals of primary teeth- An in vivo Study

Aim: Root canal treatment is often carried out in deciduous teeth to relieve pain and make the tooth functional.The main goal of instrumentation in a root canal treatment is to facilitate effective irrigation, disinfection, and filling. Sodium hypochlorite is a widely used irrigant and has been demonstrated to be an effective agent against broad spectrum of bacteria. However its toxic effects on vital tissues can result in haemolysis, skin ulceration and necrosis. The use of diode laser for endodontic applications has been investigated and proven for its efficacy in root canal sterilization. Therefore, this clinical study was conducted to evaluate and compare the efficacies of 5.25% sodium hypochlorite (NaOCl) and 810nm diode laser as disinfectants in root canals of primary teeth. This study evaluated the microbial count and the clinical success of the treatment. Materials and Methods: In 40 subjects selected based on the inclusion and exclusion criteria, Pulp tissue was extirpated from the canals and samples collected using sterile absorbent paper points . Then they were randomly divided into two groups. In Group 1, canals were prepared and irrigated with 5.25% of sodium hypochlorite, and in group 2 canals were prepared and disinfected with 810nm of diode laser. The contents of canals were collected again with a sterile paper point .Samples taken before and after procedures were cultured, and the colony-forming units (CFUs) were counted. The data was evaluated using independent sample test and paired sample test. Patients were recalled for clinical and radiographic evaluation after 3 and 6 months. Results: There was a significant difference between the mean CFU of laser and sodium Hypochlorite ( p&lt;.001). Clinical evaluation after 3 and 6 months showed no pain, swelling, sinus tract or mobility .Radiographically too there was absence of premature exfoliation, periodontal widening, internal/external resorption and periapical or furcal radiolucency. Conclusion: Both 810nm diode laser and 5.25% sodium hypochlorite were effective in reducing bacterial count in root canals of primary teeth. However 810nm diode laser reduced microbial count of root canals more as compared to 5.25% NaOCl.

Mid-term efficacy and postoperative wound management of laser hemorrhoidoplasty (LHP) vs conventional excisional hemorrhoidectomy in grade III hemorrhoidal disease: the twisting trend

PurposeHemorrhoidal disease (HD) is a common condition, and several surgical techniques have been proposed to date without being able to achieve definitive consensus on their use and indications. Laser hemorrhoidoplasty (LHP) is a minimally invasive procedure for HD treatment determining the shrinkage of the hemorrhoidal piles by diode laser limiting the postoperative discomfort and pain. The aim of the current study was to evaluate the postoperative outcomes of HD patients undergoing LHP vs conventional Milligan-Morgan hemorrhoidectomy (MM).MethodPostoperative pain, wound care management, symptoms’ resolution, patients’ quality of life, and length of return to daily activity of grade III symptomatic HD patients undergoing LHP vs MM were retrospectively evaluated. The patients were followed-up for recurrence of prolapsed hemorrhoid or symptoms.ResultFrom January 2018 to December 2019, 93 patients received conventional Milligan Morgan as control group and 81 patients received laser hemorrhoidoplasty treatment using a 1470-nm diode laser. No significant intraoperative complications occurred in both groups. Laser hemorrhoidoplasty patients experienced lower postoperative pain score (p < 0.0001) and smoother wound management. After 25 ± 8 months follow-up, the recurrence of symptoms occurred in 8.1% after Milligan-Morgan and 21.6% after laser hemorrhoidoplasty (p < 0.05) with a similar Rorvik score (7.8 ± 2.6 in LHP group vs 7.6 ± 1.9 in MM group, p = 0.12).ConclusionLHP demonstrated high efficacy in selected HD patients guaranteeing lower postoperative pain, easier wound care, higher rate of symptoms resolution, and greater patient appreciation compared to MM, even though it had a higher recurrence rate. Larger comparative studies are needed to address this issue.

Laser-Assisted Vascular Malformation Resection: A Novel Surgical Approach.

Vascular malformations can be treated using sclerotherapy agents like alcohol, polidocanol, or sodium tetradecyl sulfate foam and embolization treatments. These endovascular treatments may cause severe complications as pulmonary embolism and thrombosis. 980-nm diode lasers (DLs) are common devices used by many specialties as plastic surgeons, dermatologists, and vascular surgeons. Laser energy is excellently absorbed in water and hemoglobin, which makes it ideal for adipose tissue and deep lesions. We treated our patient using a DL. Our surgical approach allowed total excision of the arteriovenous malformation (AVM), which decreased the size of the tumor allowing a smaller incision and eased the dissection plane. We believe that lasers will be used more frequently on AVM treatments.

A COMPARATIVE EVALUATION OF THE EFFICACY OF TEETH WHITENING AGENT WITH AND WITHOUT DIODE LASER: A SPLIT-MOUTH STUDY.

Over the decades, the demand for teeth whitening has increased which has prompted the creation of numerous novel bleaching products. A teethwhitening product called Synergy gel makes claim to cause no signicant sensitivity, is highly effective, has ease of handling, and is used without a gingival barrier. Hence, this study is to evaluate the efcacy of teeth-whitening agents with and without the use of a diode laser. The teeth Method: in this split-mouth design were grouped into group A (Novo Synergy tooth whitening with an 810nm diode laser) and group B (Only Novo Synergy tooth whitening). There is a signicant difference between both groups at imme Result: diate and 15 days. But, there is no signicant difference between both groups at 3 months. The use of diode lasers (810nm) to enhance bleaching ha Conclusion: s signicant efcacy to that of the synergy gel bleaching but for a shorter period of time.

Evaluation of patient-related outcomes following treatment of temporomandibular disorders with a 940-nm diode laser: a retrospective clinical pilot study

Evaluation of patient-related outcomes following treatment of temporomandibular disorders with a 940-nm diode laser: a retrospective clinical pilot study

Treating Nerve Injury after Endodontic Microsurgery Using Laser Photobiomodulation: A Report of 2 Cases

The purpose of this case report was to inform dentists and dental specialists about a noninvasive, viable treatment option that could aid in the recovery of patients who have experienced iatrogenic nerve injuries. Nerve injury is an inherent risk of many dental procedures and a complication that can negatively impact a patient’s quality of life and activities of daily living. Managing neural injuries presents a challenge for clinicians because there are no standard protocols reported in the literature. Although spontaneous healing of these injuries can occur, the duration and degree of healing can vary greatly between individuals. Photobiomodulation (PBM) therapy is used as an adjunct in medicine for functional nerve recovery. Once target tissues are illuminated with a low-level laser during PBM, the light energy is absorbed by the mitochondria causing adenosine triphosphate production, modulation of reactive oxygen species, and the release of nitric oxide. These cellular changes explain why PBM has been shown to aid in cell repair, vasodilation, a reduction in inflammation, accelerated healing, and an improvement in postoperative pain. This case report presents 2 patients with neurosensory alterations after endodontic microsurgery with a significant improvement in their condition after PBM treatment using a 940-nm diode laser.

The efficacy of laser haemorrhoidoplasty (LHP) in the treatment of symptomatic haemorrhoidal disease: Anobservational cohort study.

Laser haemorrhoidoplasty (LHP) is an emerging nonexcisional surgical procedure in which the arteriovenous flow of the haemorrhoidal plexus is interrupted through laser coagulation. The aim of this cohort study was to assess efficacy of LHP in treating symptomatic haemorrhoidal disease through patient satisfaction, remission of symptoms (blood loss, pain, itching, soiling, mucosal prolapse) and recurrence of haemorrhoids. Patients who underwent treatment for symptomatic haemorrhoids (degrees 1-4) through an LHP procedure between 2015 and 2021 were included in the study. A 1470 nm-diode laser was used. A total of 200 patients (71% male, average age 51 years) were analysed. Primary outcomes were patient satisfaction and/or complete recovery of symptoms. Secondary outcomes were operating time, complications and recurrence rates. Patient satisfaction, postoperative blood loss, pain and complications were evaluated 6-7 weeks postoperatively. Room turnover time and operating time were documented. Recurrence of haemorrhoids following LHP treatment within 1 year was evaluated. Patient satisfaction regarding LHP treatment was reached in 155 (84,7%) patients. Postoperative blood loss was reported by 44 (24,0%) patients during time of evaluation. Twenty-four (13,1%) patients reported postoperative pain after 6-7 weeks. Postoperative complications occurred in seven patients (3 anal fissures, 2 perianal abscess, 1 perianal fistula, 1 postoperative anaemia). Room turnover time (patient in to patient out) was 21 min with an average operating time of 7min. Recurrence of haemorrhoids within 1 year occurred in 50 (27,3%) patients. Laser haemorrhoidoplasty appears to be a promising and effective nonexcisional surgical procedure in the treatment of symptomatic haemorrhoidal disease with high patient satisfaction, acceptable postoperative symptoms, minimal complications and short operating times.

Laser-activated irrigation: Cavitation and streaming effects from dental lasers

IntroductionThe aim of the present study was to assess the generation of laser-activated irrigation (LAI) with a 9,300-nm CO2 laser, a 455- and 970-nm diode laser, as well as an 810- and 980-nm diode laser with and without carbon-coated “hot tips” for improved irrigation in endodontics. Therefore, the formation of cavitation bubbles at the laser tip ends in different liquids was evaluated and compared with the traditionally applied Er:YAG laser.MethodsThe CO2 laser was applied at different power settings at a repetition rate of 14 Hz, SIROLASE for each wavelength at 10% Duty Cycle, and WISER with both wavelengths at different power settings and wavelengths. The LAI was videotaped with a high-speed camera. To measure the streaming velocity due to cavitation, all lasers were loosely coated with carbon particles and activated in pure water. Then, due to LAI, moving particles were videotaped with the same high-speed camera setup. To determine the streaming velocities, the movement of one carbon particle was tracked with the help of a measuring tool in ImageJP software and streaming velocities were calculated.ResultsWith both diode laser devices at four wavelengths, it was only possible to introduce clear cavitation bubbles with low-power parameters (180 mW for the SIROLASE and 200 mW average power for the WISER laser), with the black coating of the laser tips. The 9,300-nm CO2 laser produced clear cavitation bubbles with all tested parameters. Consequently, all tested lasers produced streaming of the liquid, with decreasing velocities at increasing distances from the laser tip: Er:YAG laser 6.4 m/s, CO2 laser up to 5 m/s, and diode lasers in the range of 0.01–0.09 m/s. LIA with the Er:YAG and 9,300-nm CO2 lasers generated high and similar streaming velocities. The diode lasers tested generated significantly lower streaming velocities.

The Effect of Laser Diode 940 nm on Decreasing Oropharyngeal Pain After Bimaxillary Orthognathic Surgery: A Double-Blind Randomized Trial Study

Background: Due to its invasiveness and length, bimaxillary orthognathic surgery causes highly excruciating pain in the oropharyngeal area for the patient. There are several ways to reduce this pain, including prescribing painkillers and anti-inflammatory drugs. The aim of this study was to evaluate the effect of photobiomodulation by a 940-nm laser on reducing pain in the oropharyngeal area after bimaxillary orthognathic surgery. Methods: This randomized clinical trial study was performed on 40 patients aged 17-40 years who were candidates for bimaxillary orthognathic surgery referred to the Department of Oral and Maxillofacial Surgery of Besat hospital in 2021. All patients in the intervention group underwent the photobiomodulation of the oropharyngeal area with a 940-nm diode laser immediately after the end of bimaxillary orthognathic surgery. Sore throat, jaw pain, pain when swallowing, and stridor were recorded in the first to fifth days after surgery. Finally, changes in the mean score of indices were compared within and between the two groups using repeated measure analysis of variance. Results: The mean age of patients in the intervention and control groups was 22.4±4.38 and 25.15±5.48 years, respectively (P=0.09). The pain score in the four areas studied in both intervention and control groups had a decreasing trend over time, which was statistically significant (P&lt;0.001). In addition, the difference in the trend between the two groups was statistically significant so that in the intervention group, the decreasing trend was more severe (P&lt;0.05). Eventually, a significant interaction was observed between the type of intervention and time in all four areas (P&lt;0.05). Conclusions: The results showed that the use of a 940-nm diode laser led to a significant reduction in all four areas of sore throat, pain when swallowing, and stridor after bimaxillary orthognathic surgery.