Review Article

Laser Effects on the Prevention and Treatment of Dentinal Hypersensitivity: A Systematic Review

Fahimeh Rezazadeh, Paria Dehghanian, Dana Jafarpour

Journal of Lasers in Medical Sciences, Vol. 10 No. 1 (2019), 18 December 2018, Page 1-11

Introduction: Dentinal hypersensitivity (DH) is an acute intensive tooth pain which can lead to dental annoyances during eating and drinking. Stimulating exposed dentinal tubules by either kind of thermal, tactile, chemical and/or osmotic stimuli is believed to be the cause of this pain. It is hypothesized that dentinal tubules’ orifice occlusion (DOO) can help relieve such dental irritations. Thus, this systematic review was conducted to evaluate the effectiveness of laser application as a prevention and treatment modality on DH reduction.
Methods: Electronic databases (MEDLINE, SCOPUS) were searched among randomized clinical trials from January 2007 to December 2016. The extraction of data and quality assessments were carried out by different independent observers.
Results: A total of 499 items were found of which3 9 relevant articles were extracted. The profound findings proved lasers’ effectiveness as a treatment of DH. Although some of the researches reported no significant difference between laser and other desensitizing agents, most of the studies suggested that better results (both rapid and long-lasting) were obtained in combined modalities. Furthermore, the preventive role of this new technology has been emphasized as well. Nd-YAG (neodymium-doped yttrium aluminum garnet) and diode lasers reduce DH after bleaching. Lasers can also protect cervical restorations from DH due to tubular occlusion. Moreover, it is suggested to apply lasers in relief of DH following scaling and root planning. Nevertheless, a few researchers dispute its beneficence as a result of placebo effect.
Conclusion: The results obtained from several studies in the present review revealed that the application of lasers is effective not only in terms of treatment of DH, but also in the prevention of this intensive tooth pain. Among various types of lasers, the application of Nd:YAG laser has shown the best results in DH treatment.

The Use of Laser Therapy for Patients with Fibromyalgia: A Critical Literary Review

Serguei Borisovich Kisselev, Sergey Vladimirovich Moskvin

Journal of Lasers in Medical Sciences, Vol. 10 No. 1 (2019), 18 December 2018, Page 12-20

The management of pain – despite many anaesthetic drugs – remains to be an urgent task. If the goal is to achieve permanent pain relief – and not to temporarily mask the pain (masking pathology) – then this goal can only be achieved by treating pain with physiotherapeutic methods, the most universal and effective of which, is low level laser therapy (LLLT).
The treatment methods vary fundamentally in the case of neuropathic (nonspecific, primary) pain, which includes pain with the localization of the trigger points (TP) and nociceptive (specific, secondary), which includes all types of pain resulting from trauma, inflammation, etc.
When treating patients with fibromyalgia (FM), a comprehensive approach is required, using different methods of laser therapy and guided by well-known rules. These rules include setting all the correct parameters of the laser exposure (wavelength, operating mode, power, exposure, etc), limiting exposure and power to optimal values and limiting the total time of the procedure and the number of procedures per course.

Modulation of Toxin-Antitoxin System Rnl AB Type II in Phage-Resistant Gammaproteobacteria Surviving Photodynamic Treatment

Nava Hosseini, Maryam Pourhajibagher, Nasim Chiniforush, Nazanin Hosseinkhan, Parizad Rezaie, Abbas Bahador

Journal of Lasers in Medical Sciences, Vol. 10 No. 1 (2019), 18 December 2018, Page 21-28

Type II toxin-antitoxin (TA) systems are the particular type of TA modules which take part in different kinds of cellular actions, such as biofilm formation, persistence, stress endurance, defense of the bacterial cell against multiple phage attacks, plasmid maintenance, and programmed cell death in favor of bacterial population. Although several bioinformatics and Pet lab studies have already been conducted to understand the functionality of already discovered TA systems, still, more work in this area is required. Rnl AB type II TA module, which is composed of RnlA toxin and RnlB antitoxin, is a newly discovered type II TA module which takes part in the defense mechanism against T4 bacteriophage attack in Escherichia coli K-12 strain MH1 that has not been widely studied in other bacteria. Because of the significant role of class Gammaproteobacteriacea in a diverse range of health problems, we chose here to focus on this class to survey the presence of the Rnl AB TA module. For better categorization and description of the distribution of this module in this class of bacteria, the corresponding phylogenetic trees are illustrated here. Neighbor-joining and the maximum parsimony methods were used in this study to take a look at the distribution of domains present in RnlA and RnlB proteins, among members of Gammaproteobacteria. Also, the possible roles of photodynamic therapy (PDT) in providing a substrate for better phage therapy are herein discussed.

Original Article

The Effect of Percutaneous Laser Disc Decompression on Reducing Pain and Disability in Patients With Lumbar Disc Herniation

Sirous Momenzadeh, Alireza Koosha, Morteza Kazempoor Monfared, Jafar Bairami, Alireza Zali, Davood Ommi, Behnam Hosseini, Masoud Hashemi, Shahram Sayadi, Reza Aryani, Fatemeh Nematollahi, Leila Nematollahi, Maryam Barati

Journal of Lasers in Medical Sciences, Vol. 10 No. 1 (2019), 18 December 2018, Page 29-32

Introduction: As low back pain incidence is increasing, noninvasive modalities are gaining attention for their ability to achieve the best possible outcome with the least complications. Percutaneous laser disc decompression (PLDD) is currently popular for this purpose. This study aims to evaluate the effect of PLDD on disability and pain reduction in patients with lumbar disc herniation.
Methods: Thirty patients were enrolled in this study. Spinal nerve blocks were conducted by laser discectomy single stage injection of a needle into the disc space. The nucleus pulposus of herniated discs were irradiated with laser in order to vaporize a small part of the nucleus pulposus of the intervertebral discs and reduce the voluminosity of diseased discs. Patients were treated with 1000 J of 980 nm diode laser with 5 W energy. In order to measure the severity of pain, visual analog scale (VAS) and also ODI (Oswestry Disability Index) were used. Data were analyzed using SPSS version 12.
Results: Thirty patients participated in this trial including 11 men and 19 women with a mean age (SD) of 40.8 (10.8) years. The mean patients VAS score and ODI level before and after discectomy showed statistically significant differences. The mean VAS and ODI scores showed no statistical difference between males and females (P < 0.05) and percutaneous laser discectomy decreased the VAS and ODI at both groups of patients similarly.
Conclusion: We found the use of PLDD reduces pain and disability in patients as a noninvasive procedure.

Clinical Investigation of 940 nm Diode Laser Power Bleaching: An In Vivo Study

Mohammed Al-Maliky

Journal of Lasers in Medical Sciences, Vol. 10 No. 1 (2019), 18 December 2018, Page 33-36

Introduction: The increased demand by patient to whiten their teeth in short time had made in-office bleaching procedure the common one. The accompanying tooth sensitivity remains an important factor affecting patients physically and psychologically. The aim of this in vivo study was to observe the effectiveness of 940 nm diode laser in combination with bleaching gel by analyzing tooth sensitivity and colour change.
Methods: Fourteen patients treated by laser-assisted bleaching using diode laser at 940 nm and bleaching gel containing 38% hydrogen peroxide. Tooth sensitivity recorded during and after treatment at 6 hours and 1 day using visual analogue scale (VAS). Tooth shade had recorded before and after bleaching using Vita classical brightness scale.
Results: Patients whom did not experienced pain during and after the treatment were 78.60% and 92.90%, respectively. Tooth brightness change after treatment was statistically different (P = 0.001).
Conclusion: Diode laser of 940 nm is an effective adjunctive tool for reducing tooth sensitivity originated from high concentration H2O2 bleaching gel.

Efficacy of High-Power Laser in Alleviating Pain and Improving Function of Patients With Patellofemoral Pain Syndrome: A Single-Blind Randomized Controlled Trial

Farshad Nouri, Seyed Ahmad Raeissadat, Dariush Eliaspour, Seyed Mansoor Rayegani, Maryam Sadat Rahimi, Behnaz Movahedi

Journal of Lasers in Medical Sciences, Vol. 10 No. 1 (2019), 18 December 2018, Page 37-43

Introduction: In this study, a single-blind and randomized controlled trial (RCT) for assessing the effectiveness of high-power (up to 12 W) laser therapy (HPLT) on patients with patellofemoral pain syndrome (PFPS) was carried out.
Methods: Forty-four patients were randomly assigned to two treatment groups by generating random numbers with MATLAB 2014b software, where odd and even numbers were attributed to sham laser group (group A) and actual laser group (group B), respectively. Group B patients underwent HPLT with total dose of 300 J/session for 5 consecutive sessions separated by a 2-day interval. On the other hand, sham laser was applied to group A patients. Both groups had the same exercise therapy programs during the study period (3 months). The exercise therapy program included isometric knee exercise for 3 sets per day and 10 times in each set, with duration of 10 seconds per time and straight leg raise for 15 seconds 10 times a day. The group codes of patients were not revealed to subjects and data analyzer until completion of the study. Kujala, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and visual analog scale (VAS) questionnaires were chosen as outcome measures. These questionnaires were completed at three points during the study; at the beginning of the study to obtain the pre-therapy conditions and one month and three months after the start of the study to evaluate post-therapy conditions.
Results: Two main analyses were conducted: within-group and between-group analyses. Within-group analyses indicated significant improvements in respect to all measurements where pre-therapy and post-therapy comparisons were conducted in both groups (P < 0.05). On the other hand, between-group comparisons did not reveal any statistically significant functional difference between group A and group B regarding the evaluative criteria (P > 0.05) except for pain VAS (P < 0.05).
Conclusion: This study indicated that short-term HPLT accompanied by appropriate exercise regimen significantly decreased pain in patients with PFPS. But it was not recommended as an efficient modality in functional improvement. Also, it was observed that, in the short-term period of study, HPLT was a safe modality.

Numerical Modeling and Clinical Evaluation of Pulsed Dye Laser and Copper Vapor Laser in Skin Vascular Lesions Treatment

Svetlana Viktorovna Klyuchareva, Igor Vladimirovich Ponomarev, Alexandra Evgenyevna Pushkareva

Journal of Lasers in Medical Sciences, Vol. 10 No. 1 (2019), 18 December 2018, Page 44-49

Introduction: Different yellow lasers have been successfully used for the treatment of vascular lesions. This study is aimed to ascertain the role and efficiency of copper vapor lasers (CVLs) and pulsed dye lasers (PDLs) for the treatment of vascular lesions using numerical modeling and to compare results with our clinical experience. In this study we aimed to develop criteria for the choice of more efficient laser exposure mode, investigate more relevant modes of laser irradiation to ensure selective photothermolysis of target vessels, and compare the CVL and PDL efficiency in the course of patients with skin vascular lesions (SVL) treatment.
Methods: We performed numerical simulation of the processes of heating a vessel with CVL and PDL to temperatures at which its coagulation could occur. Calculated fluencies were compared with clinical results of laser therapy performed on 1242 patients with skin hemangiomas and vascular malformations (SHVM), including 635 patients treated with CVL and 607 patients treated with PDL. PDL and CVL provided excellent results in 40 and ten days after treatment. The treatment was not painful. Patients did not need anesthesia. Postoperative crusts were greater with PDL than with CVL.
Results: Results of computer simulation of a selective vessel heating using PDL and CVL radiation are presented. By results obtained, depth of the location and sizes of vessels that could be selectively heated to more than 75°C are determined.
Conclusion: Based on calculated and clinical data, the heating mode for dysplastic vessels using a series of CVL micropulses could be regarded to be safer and more efficient than the mode of a PDL short, powerful pulse.

Histopathological Changes of the Retina After Nd: YAG Laser Thrombolysis in Branch Retinal Vein Occlusion: An Experimental Study

Salwa Ahmed Abdelkawi, Aziza Ahmed Hassan, Dina Fouad Ghoneim, Ahmed Tamer Sayed Saif

Journal of Lasers in Medical Sciences, Vol. 10 No. 1 (2019), 18 December 2018, Page 50-55

Introduction: The efficacy of many therapeutics techniques for treatment of branch retinal vein occlusion (BRVO) has been the subject of many investigations. The aim of the present work is to evaluate the transluminal Nd: YAG laser thrombolysis as a new therapeutic approach used for treatment of BRVO in rabbits as an experimental model.
Methods: Four rabbits were considered as a control (n=8 eyes); occlusion of the branch retinal veins was performed by using a dye enhancing thrombus formation in right eyes of 10 rabbits (n=10 eyes). Thrombi in the retinal veins were induced by intravenous injection of rose bengal solution as a photosensitizer immediately before the argon laser application with a power of 1200 mW, a spot size of 100 μm, and a duration of 20 ms. One week later, transluminal Nd: YAG laser thrombolysis (30 mJ, 3 pulses/4 ns) was employed to the site of occluded veins, until the thrombi were partially or completely shattered. The rabbits were followed up after 4 days, 1 week and 2 weeks for slit lamp fundus examination and the treated retinas were isolated for histopathological examination.
Results: Argon laser photothrombosis induced complete BRVO with some vitreous hemorrhage, destruction, and necrosis in the surrounding retinal layers. Moreover, one week later, Nd: YAG laser thrombolysis showed complete venous flow, minimal vitreous hemorrhage, reperfused retina, complete veins improvement. Follow up after 2 weeks revealed more improvement of all retinal layers.
Conclusion: Treatment with transluminal Nd: YAG laser thrombolysis represented a novel therapeutic modality in BRVO.

Introduction: Maturity-onset diabetes mellitus affecting the elderly population is marked by insulin resistance and decreased insulin production. The relationship between periodontitis and diabetes is bidirectional. Type 2 diabetic patients are more prone to chronic periodontitis (CP) and severe periodontitis affects the glycemic control in such patients. Recently, dental diode laser has become an effective tool in controlling CP. To date, very few studies have been conducted to check the efficacy of diode laser in control of periodontal destruction in type 2 diabetes mellitus (DM2) patients. Hence, the need of the study was to evaluate whether diode laser helps improvement of periodontal outcome and reduction in anaerobic bacteria in elderly diabetic patients with CP.
Methods: Forty DM2 patients with CP were randomized into group A (control): scaling and root planing (SRP) only and group B (test): SRP followed by soft tissue dental diode laser (808 nm) application. Four patients (2 in each group) were lost during follow up. Clinical parameters, plaque samples and glycated hemoglobin levels were evaluated at both baseline and 90 days post-treatment.
Results: Improvement in clinical, microbiological and glycemic parameters were noted in the group that received SRP as well as SRP + LANAP (laser-assisted new attachment procedure). The reductions in clinical parameters were statistically significant after 3 months (P < 0.001). The microbial analysis of plaque samples for Aggregatibacter actinomycetemcomitans (Aa) and Porphyromonas gingivalis (Pg) decreased significantly after 3 months in group B than in group A. Glycated hemoglobin level (HbA1c) decreased significantly after 90 days in both the groups (P < 0.001) with more reduction in the SRP+LANAP group (6.49%) in comparison to SRP alone (16.25% vs. 9.76%). However, on the intergroup comparison, the difference in HbA1c reduction was nonsignificant.
Conclusion: Laser as an adjunct to SRP is an effective procedure for improving clinical and microbiological parameters in maturity onset diabetes mellitus patients with CP. Also, there was a better improvement in glycemic control in the test group compared to control group after 3 months. Hence, medically compromised patients like DM2 with CP with delayed wound healing can effectively be treated by laser as an adjunct to nonsurgical periodontal therapy for better results.

Feasibility Study on Discrimination of Neo-plastic and Non-Neoplastic Gastric Tissues Using Spark Discharge Assisted Laser Induced Breakdown Spectroscopy

Aida Seifalinezhad, Maryam Bahreini, Mohammad Mahdi Hassani Matin, Seyed Hassan Tavassoli

Journal of Lasers in Medical Sciences, Vol. 10 No. 1 (2019), 18 December 2018, Page 64-69

Introduction: The present work is a novel in vitro study that evaluated the possibility of diagnosing neoplastic from nonneoplastic gastric tissues using spark discharge assisted laser induced breakdown spectroscopy (SD-LIBS) method.
Methods: In these experiments, the low energy laser pulses ablated a tiny amount of tissue surface leading to plasma formation. Then, a spark discharge was applied to plasma in order to intensify the plasma radiation. Light emission from plasma was recorded as spectra which were analyzed. Gastric tissues of 5 people were studied through this method.
Results: The SD-LIBS technique had the potential to discriminate normal and cancerous tissues based on the significant differences in the intensities of some particular elements. The comparison of normalized calcium (Ca) and magnesium (Mg) peaks of neoplastic and nonneoplastic gastric tissues could be viewed as a practical measure for tissue discrimination since Ca and Mg peaks in spectra of neoplastic were noticeably higher than nonneoplastic.
Conclusion: Considering the identification of gastric cancer, the applied method in these experiments seems quite fast, noninvasive and cost-effective with respect to other conventional methods. The significant increment of specific Ca and Mg lines of neoplastic gastric tissues in comparison to the nonneoplastic ones can be considered as valuable information that might bring about tissue classification. The number of samples in this work, however, was not sufficient for a decisive conclusion and further researches is needed to generalize this idea.

Is Holmium Laser an Appropriate Modality to Treat Genital Warts?

Saleh Ghiasy, Morteza Fallah-Karkan, Mohammad Reza Razzaghi, Arash Ranjbar, Amirhosein Rahavian, Babak Javanmard

Journal of Lasers in Medical Sciences, Vol. 10 No. 1 (2019), 18 December 2018, Page 70-74

Introduction: Genital warts in young adults aged 18-28 years are very common. Several approaches are routinely used in the treatment of warts, viz., medical treatment (podophyllin and trichloroacetic acid), conventional surgery (excision or electrocautery), cryotherapy, and laser treatment. Because of high recurrence rates after treatment, complications and long duration of treatment, newer modalities have been developed. One of these newer methods is laser, which has been used in several urologic diseases. However, there are only a few studies about use of Holmium laser for treatment of genital warts. This retrospective study compared the success rate of Holmium laser with other available treatments for genital warts.
Methods: Between October 2011 and May 2016, 142 patients with genital warts attended the urology clinics at Shohada-e-Tajrish hospital in Tehran, Iran. Out of these, a total of 101 patients were included in this study consisting of 42, 39, 11 and 9 patients treated with cryotherapy, laser, conventional surgery and podophyllin respectively.
Results: The most successfully cleared lesions were seen in the holmium laser treatment group (P = 0.001). The lowest recurrence rate was observed in the holmium laser treatment group (P = 0.001). 17 patients had one of these following problems: dysuria, initial hematuria or a change in the force and caliber of their urinary stream that after physical examination showed them to have a meatal wart. These patients then underwent cystoscopy up to urinary sphincter. All of them in addition to the meatus wart had a penile shaft lesion(s). Thirteen patients had meatal lesions, 9 of whom received holmium laser therapy and 4 patients were treated with electrocautery. Based on routine follow up after treatment, none of the patients treated with holmium laser had urinary stricture, but one case treated with electrocautery returned with a penile urethral stricture.
Conclusion: This study showed that treatment with Holmium laser has the highest clearance rate (92.2%) and lowest recurrence rate (14.3%) compared to other available treatments in this study. It may be concluded that holmium laser is a safe and effective treatment for genital warts with a low rate of recurrence.

Case Report

High Power Laser and Photobiomodulation in Oral Surgery: Case Report

Júlia Gomes Lúcio de Araújo, Erika Michele dos Santos Araújo, Fernanda Cristina Nogueira Rodrigues, Marco Aurélio Benini Paschoal, Andrea Dias Neves Lago

Journal of Lasers in Medical Sciences, Vol. 10 No. 1 (2019), 18 December 2018, Page 75-78

Introduction: The labial frenum is a fold of mucous membrane that attaches the lip and the cheek to the alveolar mucosa, the gingiva, and the underlying periosteum. In some cases, its presence can cause a midline diastema, periodontal diseases related to food impaction, or retention of biofilm, among others. In such cases, lip frenectomy is indicated as treatment, which can be performed with a scalpel (conventional method), an electric scalpel, or a surgical laser.
Objective: To show a clinical case performed at Laser Extension Project in Dentistry, Federal University of Maranhão grounded in a literature review.
Case Presentation: A laser frenectomy was performed on a female patient, aged 20, who had a diastema between the upper central incisors and an indication for frenum removal. The high-power diode laser is excellent for procedures in soft tissue because its wavelength is well absorbed by hemoglobin and other pigments; its use also allows a reduction in the amount of anesthetic and medicines used. The parameters used were 2 W, in a continuous mode, 808 nm infrared emission; with delivery of the beam through optical fiber 300 μM; energy of 120 J; 20 pps.
Conclusion: the high power diode laser allowed a satisfactory result, the procedure was safe, the technique was a simple one and of reduced clinical time, as mentioned in the literature. It is worth noting that the technique is dependent on the skill of the professional performing it.