Journal of Lasers in Medical Sciences

INTRODUCTION: The aim of this study was to investigate the Scanning Electron Microscope (SEM) analysis of tooth surface irradiated by different parameters of Er:YAG laser.

METHODS: 15 caries-free extracted human third molars were used in this study. The teeth were put into 5 groups for laser irradiation as follows: Group 1 (power: 2.5 W, Energy: 250 mJ); Group 2(power: 3 W, Energy: 300 mJ); Group 3 (power: 3.5 W, Energy: 350 mJ); Group 4 (power: 4 W, Energy: 400 mJ); Group 5 (power: 4.5 W, Energy: 450 mJ). All samples were prepared by repetition rate of 10 Hz. Then,the samples were prepared for SEM examination.

RESULTS: The SEM images showed cleaned ablated surface and exposed dentinal tubules, without production of smear layer.

CONCLUSION: It can be concluded that Er:YAG laser can be an alternative technique for surface treatment and can be considered as safe as the conventional methods,like turbine and bur.

INTRODUCTION: Acne scar is formed after severe episodes of acne in teen and earlyadult years. Several treatment options have been used for depressed acne scars suchas punch grafting, punch excision carbon dioxide (CO2) laser etc. Moreover, Studiesshow that laser skin resurfacing such as CO2 fractional can effectively treat depressedacne scars. We investigated the efficacy of fractional CO2 laser in acne scar.

METHODS: In this clinical trial; we used CO2 fractional laser (Unit: eCO2 LutronicKorea; FDA approved) in 15 female cases with an age range of 20-40 years old.They underwent 3 sessions of laser resurfacing at one month intervals. In the first session we used laser with a density of 150 and fluency of 70 with a 4mm diameter circular spot in static mode on depressed acne scars, and we exerted laser with density of 100 and fluency 70 with 12 mm diameter square spot in static mode on all involved skin in the other sessions. Photographs were taken before every process. The patients and another dermatologist filled the questionnaire concerning the percent of improvement. Finally, we compared photographs and evaluated the efficacy of CO2 fractional laser in acne scars.

RESULTS: Objective and subjective improvement was estimated about 20-70% and 30-70%, respectively, without any erythema, permanent hyperpigmentation and other adverse effects. The important point is that, participants returned back to work after 4-7 days.

CONCLUSION: The Fractional CO2 laser resurfacing can be used as a safe and efficacious method to treat depressed acne scar.

INTRODUCTION: Dentine hypersensitivity (DH) is characterized by a short sharp pain arising from the exposed dentine, in response to a thermal, evaporative, tactile, osmotic or chemical stimulus. The aim of this study was to evaluate the efficacy of Nd:YAG laser therapy and desensitizing gel (Sensikin®, Laboratorios Kin S.A., Barcelona, Spain) in treatment of dentine hypersensitivity.

METHODS: A total of 20 patients with at least 6 hypersensitive teeth were selected and divided randomly into three groups: Nd:YAG laser (10 HZ, 1W, 60 S, two times) treated group, Sensikin® treated group and a control group. Subjects were asked to apply the gel at home for the next week and 3 times a day as they were instructed. Assessment of the pain was performed by visual analyzing scale (VAS) after stimulation of the teeth by compressed air at 6 intervals: before treatment, immediately after treatment, one week, one, three and six months later. The data obtained were analyzed using the SPSS software, one way ANOVA and repeated measurement ANOVA tests.

RESULTS: VAS scores did not show any significant differences between the three groups prior to treatment (P value>0.05), but in all groups after treatment VAS scores differed significantly in comparison to VAS scores before treatment (Pvalue<0.05). This statistically significant difference in the control group demonstrated a placebo effect. However, the efficacy between the three groups was not significantly different. An overall comparison indicated no significant differences at various time intervals.

CONCLUSION: Nd:YAG laser and desensitizing gel effectively reduce DH. However, we found no significant statistical differences between these two groups compared with the control group. 

INTRODUCTION: Low back pain is one of the most common musculoskeletal disorders,which is prevalent among the public population. Depending on the severity of the patients’ pain, different treatments are selected for them. Few studies have addressed, so far, the therapeutic effects of laser in such pains and different results have been published in this regard. The aim of this study is to investigate the therapeutic effect of low intensity laser therapy (LILT) on these diseases.

METHODS: Sixty patients are randomly divided into three groups, one received low intensity laser therapy (LILT), the second group the low intensity laser and physical exercises simultaneously and the other the laser placebo and physical exercises simultaneously. Laser therapy was performed for 6 weeks, two sessions per week.Pain and disability were measured and compared, at 0, 6 and 12 weeks after the treatment in the three groups.

RESULTS: Patient’s disability in groups 1 and 2 at week 6 showed a significant improvement compared to the beginning of the study. (Group I, P=0.02, P=0.012, group II, P=0.031, P=0.042, respectively).The rate of pain and disability at the week 12 improved significantly compared to the week 6 of the study in each group of 1 and 2. (Group I, P=0.002, P=0.02, group II, P=0.043, P=0.02, respectively). In the comparison of the groups at week 12, the values of pain (P=0.02) and disability (P=0.03) had improved in group I (laser therapy accompanied with physical exercise).

CONCLUSION: Our Results revealed that laser therapy accompanied with physical exercise can be the most effective way for improving the chronic back pains including pain relief and reduction of disability in the patients.

INTRODUCTION: Low-level laser therapy (LLLT) is thought to have analgesic and biomodulatory effects. Our objective was to assess the pain-relieving effect of LLLT and possible changes in joint stiffness and disability of patients with knee osteoarthritis (KOA) and compare it to the more commonly used modality; therapeutic ultrasound(US).

METHODS: 37 patients with mild or moderate KOA were randomized to receive either LLLT, placebo LLLT or US. All patients received a common treatment including acetaminophen (up to 2gr/d) and medical advices for lifestyle modification and exercise. Treatments were delivered 5 times a week over a period of 2 weeks. Active laser group was treated with a diode laser (wavelength 880 nm, continuous wave, power 50 mW) at a dose of 6 J/point (24 J/knee). The placebo control group was treated with an ineffective probe (power 0 mW) of the same appearance. The third group received pulsed ultrasound with an intensity of 1.5-2 w/cm2, and for 5 minutes per knee. Visual Analogue Scale (VAS) and Western Ontario MacMaster (WOMAC) questionnaires were used for data gathering before,1 and 3 months after completing the therapy.

RESULTS: Pain reduced in all 3 groups but laser was superior in comparison. Stiffness improved 1 mo after therapy in the laser group but not in the others. Disability decreased in both laser and US groups (more significantly in the laser group) but not in the placebo group.

CONCLUSION: Our results show that LLLT reduces pain, joint stiffness and disability in KOA and is superior to placebo and US.

It is the output power and density of the lasers which determine whether a laser is a low or high-power one. If the density is less than 670mW/cm2, the laser is called a low power one. The output power of these lasers is usually less than 250mW. They use different mechanisms to accelerate wound healing such as: cellular biostimulation, improvement of circulation, vasodilation, analgesic and anti-inflammatory effects. They don’t contribute to any drug resistance, therefore, several studies have been conducted on the application of these lasers for the curing of acute, chronic and recurrent ulcers such as mucositis, aphthous ulcers, herpetic lesions and lichen planus. In this article we will survey the effects of low-power lasers in the healing of oral ulcers.

The application of laser in dentistry is considered as a favorable technique for patients due to its many advantages compare to other current methods. One of the main goals in pediatric dentistry is to provide the treatment as comfortable as possible without any risks for the care. Laser is being used in different pediatric dental conditions including caries detection, caries removal and cavity preparation, soft tissue surgery and in low level laser therapy applications. The application of current common lasers in dentistry resulted in less stress and fear in patients during dental procedures, also leading to more conservative non-invasive methods for soft and hard tissues with minimal discomfort and bleeding

The incidence of stone disease among patients with congenital renal anomalies including malrotated kidney is more than in normal population due to poor urine drainage and stasis (1). Various minimally invasive options have been used for the management. Ureteroscopy and Holmium:YAG laser lithotripsy have been reported with favorable outcomes (2). We report a 30-year-old male who presented to our hospital having a right side malrotated kidney with a large stone in it. He underwent two session of ureteroscopy and Holmium:YAG laser lithotripsy