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Lasers in Medical Sciences - Volume:8 Issue: 3, Summer 2017

Journal of Lasers in Medical Sciences
Volume:8 Issue: 3, Summer 2017

  • تاریخ انتشار: 1396/05/08
  • تعداد عناوین: 10
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  • Amirhossin Mirhashemi, Nastaran Sharifi, Mohammad Moharrami, Nasim Chiniforush Pages 101-111
    To achieve proper bond strength for porcelains, adequate surface roughness is essential, which is traditionally gained by sandblasting or acid etching with hydrofluoric (HF) acid. Nowadays with the development of laser systems, serious efforts were made to apply this new instrument for surface etching of porcelains due to easy usage, safety, and more efficiency. There are different kinds of lasers and porcelains, so choosing the ones which will be good match for each other is crucial. Besides that, changing the irradiation setting can be beneficial as well. This article reviewed 33 related studies and summarized results of etching accomplished by Nd:YAG, Er:YAG, Er,Cr:YSGG and CO2 lasers on different types of porcelains considering different laser settings and evaluation methods to bring a comprehensive insight.
    Keywords: Porcelain, Nd:YAG, Er:YAG, Er, Cr:YSGG, CO2, Conditioning, Orthodontics
  • Rafael In, Aacute, Cio Barbosa, Alexandre Marcio Marcolino, Vitor Souza, Guilherme Bertolino, Marisa De Cassia Registro Fonseca, Rinaldo Roberto De Jesus Guirro Pages 112-117
    Introduction
    The purpose of this study was to investigate the effect of low-level laser therapy (LLLT) – 660 nm and 904 nm - before grip strength protocol in healthy subjects.
    Methods
    The study included 45 healthy volunteers with an average age of 22.7 (±1.4) years, subdivided into the following groups, control group: grip strength training associated with placebo LLLT; 660 nm group: LLLT (660 nm, 20 J/cm2, power of 30 mW, and beam area of 0.06 cm2, continuous, energy 1.2 J, and exposure time 40 seconds per point) before grip strength training and 904 nm group: LLLT (904 nm, 10 J/cm2, peak power of 70 W and 0.13 cm2 beam area, with pulsed beam 9.500 Hz and 30 seconds of exposure time per point and emitted energy 1.2 J) before grip strength training. The LLLT was timed to contact 10 points located in the region of the superficial and deep flexor muscles of the fingers, with a total energy of 12.0 J per session. For the strength training protocol, the volunteer exercised their fingers with the dominant hand on a small table, elbow flexed at 90°, forearm in neutral, using a light extension handle. The Oxford protocol was performed during four weeks. The grip strength was assessed using a dynamometer (Jamar™). The data were evaluated by the analysis of variance (ANOVA) statistical method.
    Results
    In the comparison of intragroup evaluation, only the 904 nm group showed a difference compared to the baseline assessment after 4 weeks (P
    Conclusion
    In conclusion, LLLT (904 nm) applied before resistance training was effective in gaining grip strength when compared to LLLT (660 nm) and isolated strength training after 4 weeks.
    Keywords: Laser Therapy, Low-Level, Hand Strengths, Therapy, Photobiomodulation
  • Kawthar Shurrab, Nabil Kochaji, Wesam Bachir Pages 118-122
    Introduction
    The purpose of this project is to develop a mathematical model to investigate light distribution and study effective parameters such as laser power and irradiated time to get the optimal laser dosage to control hyperthermia. This study is expected to have a positive impact and a better simulation on laser treatment planning of biological tissues. Moreover, it may enable us to replace animal tests with the results of a COMSOL predictive model.
    Methods
    We used in this work COMSOL5 model to simulate the light diffusion and bio-heat equation of the mouse tissue when irradiated by 980 nm laser diode and the effect of different parameters (laser power, and irradiated time) on the surrounding tissue of the tumor treatment in order to prevent damage from excess heat
    Results
    The model was applied to study light propagation and several parameters (laser power, irradiated time) and their impact on light-heat distribution within the tumor in the mouse back tissue The best result is at laser power 0.5 W and time irradiation 0.5 seconds in order to get the maximum temperature hyperthermia at 52°C.
    Conclusion
    The goal of this study is to simulate a mouse model to control excess heating of tissue and reduce the number of animals in experimental research to get the best laser parameters that was safe for use in living animals and in human subjects.
    Keywords: Laser irradiation, Diode laser, Optical-thermal, Experimental animal, Temperature distribution, Light propagation
  • Manal Mohamed Salah-Eldin, Nevien Ahmed Sami, Dalia Gamal-Eldin Aly, Noha Sami Hanafy Pages 123-127
    Introduction
    Recently, the monochromatic excimer light (MEL) of 308 nm wavelength has shown some advantages in comparison to narrow band ultraviolet B (NB-UVB) for the treatment of vitiligo. To histopathologically compare the early effects of NB-UVB and 308-nm MEL phototherapy on vitiliginous patches using H&E and HMB-45.
    Methods
    Thirty subjects with non-segmental vitiligo lesions were treated twice a week for 6 weeks with 308-nm MEL, while NB-UVB was used to treat lesions contra laterally. Skin biopsies were taken from lesional areas before and after 6 weeks of treatment by either modality. It was prepared for light microscopy and immunohistochemical study (HMB-45). This study was performed as a clinical trial (Trial registration: http://www.pactr.org; Identifier: PACTR201705002279419)
    Results
    All lesions before treatment had labeling index (number of pigmented cells/non-pigmented cells) of 0.0 (0%). After treatment the LI for MEL was 4.2 ± 2.6, while for NB-UVB LI it was 0.3 ± 0.7. MEL showed higher statistical significance regarding increase of basal pigmented cells, and significant decrease in vacuolated keratinocytes and basal membrane thickness than NB-UVB.
    Conclusion
    Although NB-UVB is considered as treatment of choice for vitiligo, MEL is acknowledged as an effective treatment modality for vitiliginous lesions that induces more repigmentation than NB-UVB, and more rapidly, as confirmed by our study.
    Keywords: Vitiligo_Monochromatic Excimer Light (MEL)_Narrow Band Ultra-Violet B (NB UVB)_Human Melanoma Black-45 (HMB-45)
  • Mohammad Asnaashari, Hengameh Ashraf, Amir Houshang Daghayeghi, Seyed Masoud Mojahedi, Saranaz Azari-Marhabi Pages 128-131
    Introduction
    Pharmacotherapy with analgesics and non-steroidal anti-inflammatory drugs has been traditionally used to relief post-operative pain of endodontic treatments. However, due to the side effects reported for these drugs, some efforts have been made to decrease the post-operative pain of the endodontic treatments through laser irradiation. The present study aimed to evaluate the effects of low level laser therapy (LLLT) on the reduction of pain after root canal retreatment.
    Methods
    In this clinical trial, 61 patients requiring endodontic retreatments in posterior teeth were selected. A single visit endodontic retreatment was performed. After biomechanical preparation, low level laser was irradiated to the buccal and lingual mucosa overlying the apices of the target tooth in the experimental group. In the control group patients received placebo laser to eliminate the probable psychological effects of laser. Laser irradiation was done with a single dose of 808 nm wavelength (Whitening Lase II- Laser DMC, Samsung, Korea) with 100 mW power, and dose of 70 J/cm2 for 80 seconds. Pain severity was recorded before, immediately after and 4, 8, 12, 24 and 48 hours after the treatment by visual analogue scale (VAS). The pain scores were statistically analyzed by chi-square test between 2 groups. The effects of different variables on the post-operative pain experience were also studied by means of Logistic regression.
    Results
    Pain scores decreased significantly through time until 48 hours after treatment. No significant differences were observed between the 2 modalities regarding pain scores at any time. According to regression analysis, pain severity scores were lower in the laser-irradiated specimens than control groups (OR = 5.69); however, this difference was not statistically significant. Consumption of analgesics after the treatment had significant effect in decreasing post-operative pain experience (OR = 56) while factors of age, gender, laser irradiation, pre-treatment pain scores and education level did not.
    Conclusion
    Low level laser irradiation had limited effects to decrease pain associated with the endodontic retreatments in the first and second molars; however, more studies are required to assess the effects of different parameters of low level laser in this regard.
    Keywords: Endodontic retreatments, Low level laser, Pain, Visual analogue scale
  • Sergey Moskvin, Alexander Geynitz, Eugene Askhadulin Pages 132-135
    Introduction
    Treating patients with trophic ulcers (TUs) of venous etiology (VE) is a complicated socio-medical and economic problem. One of the ways to increase treatment efficiency can be a complex therapy, including combined laser action.
    Methods
    The objective of this study was a comparative evaluation of the efficiency of traditional treatment methods in patients with chronic venous diseases of C6 class, and combined laser therapy (LT) according to a new method by LASMIK® device. External exposure was conducted on the 1-4 affected area during one session for 2 minutes per zone (pulsed mode, light pulse duration of 100-130 ns, wavelength 635 nm, by a matrix emitter consisting of eight laser diodes with a surface area of 8 cm2, at a distance of up to 7 cm, pulsed power 40 W). Intravenous laser blood illumination (ILBI) was conducted in continuous mode with a wavelength of 365-405 nm (UV-spectrum) and 520-525 nm (green spectrum) alternately, during 12 daily sessions, according to a special scheme.
    Results
    The new method reduces time periods for wound surface cleansing from purulo-necrotic masses, stimulates proliferation and epithelialization processes by 2-2.7 times, compared with the conventional method.
    Conclusion
    The high efficiency of a new combined LT has been demonstrated in the treatment of TU of VE in combination with traditional methods of patients’ medical treatment.
    Keywords: trophic ulcer of venous etiology, chronic venous insufficiency, low level laser therapy
  • Ehsan Birang, Mohammad Reza Talebi Ardekani, Mahboobeh Rajabzadeh, Gloria Sarmadi, Reza Birang, Norbert Gutknecht Pages 136-142
    Introduction
    Side effects related to antibiotic therapy for peri-implantitis are rare in laser therapy (LT); therefore, the aim of this study was to evaluate the effectiveness of LT and photodynamic therapy (PDT) on patients with primary peri-implantitis.
    Methods
    In this randomized clinical trial, 40 implants presenting primary peri-implantitis in 20 patients with a mean age of 52.6 years old were included using the simple sampling technique. Periodontal treatment comprising scaling and root planing (SRP) was accomplished for the whole mouth while mechanical debridement with titanium curettes and air polishing with sodium bicarbonate powder was accomplished around the implants. The implants were randomly divided into two groups and treated with LT (control) and PDT (test). The clinical indices were measured at baseline, 6 weeks and 3 months after treatment. Real-time polymerase chain reaction (PCR) was used for analysis of microbial samples at baseline and 3-month follow-up. Data were analyzed with SPSS 20, using repeated-measures analysis of variance (ANOVA) and Friedman’s and Mann-Whitney tests (α = 0.05).
    Results
    Both groups showed statistically significant improvements in terms of bleeding on probing (P 0.05). The number of Aggregatibacter actinomycetemcomitans (P = 0.022), Tannerella forsythia (P = 0.038) and Porphyromonas gingivalis (P = 0.05) in the test group and Porphyromonas gingivalis (P = 0.015) in the control group significantly decreased.
    Conclusion
    The results suggested that LT and PDT have significant short-term benefits in the treatment of primary peri-implantitis.
    Keywords: Diode laser, peri-implantitis, photosensitizer, photodynamic therapy
  • Hojjat-Allah Abbaszadeh, Ali Asghar Peyvandi, Yousef Sadeghi, Akram Safaei, Mona Zamanian-Azodi, Maryam Sadat Khoramgah, Mostafa Rezaei-Tavirani Pages 143-149
    Introduction
    Periodontitis is a set of inflammatory disorders characterized by periodontal attachment loss and alveolar bone resorption. Because of deficiency in periodontitis mechanical therapy, this study was aimed to explore the molecular influence of the erbium-doped: yttrium aluminum garnet (Er:YAG) laser and cyclosporin A (CsA) on human gingival fibroblasts (HGFs) for improvement in periodontal diseases therapy.
    Methods
    We focused on articles that studied the proteome profiles of HGFs after treatment with laser irradiation and application of CsA. The topological features of differentially expressed proteins were analyzed using Cytoscape Version 3.4.0 followed by module selection from the protein-protein interaction (PPI) network using Cluster ONE plugin. In addition, we performed gene ontology (GO) enrichment analysis for the densely connected region and key proteins in both PPI networks.
    Results
    Analysis of PPI network of Er:YAG laser irradiation on HGFs lead to introducing YWHAZ, VCP, HNRNPU, YWHAE, UBA52, CLTC, FUS and IGHG1 as key proteins while similar analysis revealed that ACAT1, CTSD, ALDOA, ANXA2, PRDX1, LGALS3, ARHGDI and EEF1A1 are the crucial proteins related to the effect of drug. GO enrichment analysis of hub-bottleneck proteins of the 2 networks showed the different significant biological processes and cellular components. The functional enrichments of module of Er:YAG laser network are included as fatty acid transmembrane transport, cytokinesis, regulation of RNA splicing and asymmetric protein localization. There are not any significant clusters in network of HGF treated by CsA.
    Conclusion
    The results indicate that there are 2 separate biomarker panels for the 2 treatment methods.
    Keywords: Er:YAG laser_cyclosporin A (CsA)_Protein-protein interaction (PPI) network analysis_Gene ontology_human fibroblast cell
  • Nahid Derikvand, Sara Ghasemi, Mohammad Moharami, Ehsan Shafiei, Nasim Chiniforush Pages 150-154
    Introduction
    Oral lichen planus (OLP) is a mucocutaneous disease with uncertain etiology. As the etiology is unknown standard treatment modalities are not available. The traditional and common treatment relies on corticosteroids whether topical or systemic. In recent years, development of lasers made a proper path to use this instrument for treatment of the diseases which are refractory to conventional treatments. Previous studies in this field used CO2, ND:YAG, Excimer and some wavelength of diode lasers for the treatment of different types of lichen planus.
    Case Report: In this study, we present an OLP case which is treated using 980 nm diode laser. The result was measured by visual analogue scale (VAS) and clinical assessment; as a result, symptoms including pain and soreness started to decrease within a week, and by the end of a month completely subsided; the lesion disappeared totally as well. No recurrence was observed after a month and no side-effect was reported.
    Conclusion
    980 nm diode laser can be successfully used for treatment of patients with OLP.
    Keywords: Diode laser, Oral lichen planus, Laser therapy, Traditional treatment
  • Abdul Ahad, Shruti Tandon, Arundeep Kaur Lamba, Farrukh Faraz, Parimal Anand, Abdul Aleem Pages 155-159
    Introduction
    Mucus extravasation cyst is a commonly occurring lesion in oral cavity that may result from traumatic severance of a salivary gland duct with subsequent extravasation of mucus into fibrous connective tissue. After a conventional excision or marsupialization, recurrence is not uncommon. Diode laser offers an effective modality for management of such lesions.
    Case Reports: Four patients were referred with painless fluctuant swellings on labial and buccal mucosa. After recording history and clinical examination, provisional diagnosis of mucocele was made. All the lesions were excised with a diode laser and biopsy was performed. Surgical wounds were treated with low-level laser therapy (LLLT).
    Results
    Uneventful healing was observed in all 4 cases. Significant reduction in postoperative discomfort was recorded after application of LLLT. Histopathological findings were suggestive of mucus extravasation cysts.
    Conclusion
    Diode laser appears to be a good alternative to conventional modalities for the management of mucus extravasation cysts.
    Keywords: Mucocele, Mucus extravasation Cyst, Diode laser, Low-level laser therapy