An Invitro Study on The Temperature Changes of Dentin, Irradiated by CO2 and Er: Cr;YSGG Laser

Mohammad Asnaashari, Reza Fekrazad, Mohammad Ali Mozayeni, Maryam Mozayeni

Journal of Lasers in Medical Sciences, Vol. 1 No. 1 (2010), , Page 1-7

INTRODUCTION: The aim of this in-vitro study was the evaluation of mperature changes due to irradiation of two different lasers used for the reduction of dentinal hypersensitivity and their effect on the pulp damage. The study was done for two dentin thicknesses. 

METHODS: Twenty intact extracted third molars were prepared by longitudinal ground sectioning for 1 and 2 mm dentin thicknesses while a thermocouple was positioned at the inner surface of the dentin disk. Thermal evaluation was assessed by a KJT digital thermometer. During the test, the data produced by the thermometer was transferred and logged into a PC via RS232 serial port. CO2 laser (Ultra pulse,50W, 100?sec, Spot size: 0.5 mm) and Er,Cr;YSGG laser (Free-running pulse mode,0.25W, 140?sec, 12.50 milli-joules) irradiations were randomly performed upon the dentin surfaces. The collected data was analyzed by two-way ANOVA test.

RESULTS: The mean temperature rise in 1mm dentinal thickness was 8.57°C which was significantly higher than 3.63°C in 2mm dentin thickness (P<0.001) and higher than the threshold temperature for pulp damage; however, no significant difference was noted between the two lasers (P=0.355). After removing the CO2 laser, the temperature decreased to the initial level faster than the time needed for Er,Cr;YSGG laser (44.47°Cversus 62.82°C)(P<0.001). In other words, in both lasers the temperature decrease in 2mm dentinal disc was faster than 1mm dentinal disc.

CONCLUSION:  The temperature rise due to both lasers for 1mm of dentinal thickness was in excess of safe limit for the tissue and it would probably result in pulpal damage.In the case of 2mm dentinal thickness, the temperature rise was not higher than the safe limit and it would not damage the pulp in clinical conditions.

Evaluating the Efficiency of Low Level Laser Therapy (LLLT) in Combination With Intravenous Laser Therapy (IVL) on Diabetic Foot Ulcer, Added to Conventional Therapy

Soheila Mokmeli, Mahrokh Daemi, Zahra Ayatollahzadeh Shirazi, Fatemah Ayatollahzadeh Shirazi, Mitra Hajizadeh

Journal of Lasers in Medical Sciences, Vol. 1 No. 1 (2010), , Page 8-13

INTRODUCTION:: Low level laser therapy (LLLT) is gaining acceptance in clinical applications. For example, it is used as therapeutic modality in the repair of diabetic foot ulcer when conventional therapy was not effective, separately. The aim of this study is to determine the effect of local and travenous LLLT for the healing of diabetic foot ulcer.

METHODS: This study contains 74 diabetic foot-ulcers which were prone to resistance to conventional therapy. Different stages of diabetic foot are included in this study. The wounds irradiation are performed by the combination therapy of 650 nm and 860 nm laser, with the total energy density of 3.6 J/cm² plus intravenous laser therapy (IVL) with 2.5 MW, 650 nm laser used for 30 minutes. All wounds have been photographed from equal distance, before and after treatments, and all the wounds were staged by a surgeon who was disinterested and neutral about the effects of the laser therapy. Her judgments were based on the visual assessments of the wounds. All the mathematical and statistical analysis is based on the descriptive statistics which, is done by the SPSS 16.

RESULTS: in the result of this study; 62.2% (Forty-six out of the 74 ulcers) completely healed, 12.2% (Nine in numbers) healed more than 50%, 8.1% (Six in numbers) healed less than 50%, 5.4% (Four in numbers) not healed,12.2% (Nine in numbers) did not continue their treatment (less than 5 sessions of Laser therapy). Excluding, the wounds in stage 5, more than 80% of each stage’s wound, completely healed more than 50%, with in 2 months duration. In this study, we definitely can express that, all the Patients received some degrees of healing, during their laser receiving treatments.

CONCLUSION:  The combined local and intravenous LLLT promote the tissue repair process of diabetic foot ulcer. In this multi-disciplinary method, we achieved a remarkably shorter mean healing time of two months, compared with other reported studies with healing time of three to six months.

Comparing Pulsed-dye Laser with Cryotherapy in the Treatment of Common Warts

Maryam Akhyani, Amir Houshang Ehsani, Pedram Noormohammadpour, Roghieh Shamsodini, Sahar Azizahari, Shima Sayanjali

Journal of Lasers in Medical Sciences, Vol. 1 No. 1 (2010), , Page 14-19

INTRODUCTION: No modality has been identified as the treatment of chice for treating common warts. Cryothearpy and pulsed-dye laser (PDL) are among common modalities for treating these lesions. The aim of this study was to compare pulsed dye laser with cryotherapy in terms of efficacy and complications.

METHODS: Of a total of 46 patients enrolled in this study, 7 patients withdrew the study, 20 patients underwent cryotherapy and 19 patients underwent PDL. Patients underwent a maximum of 4 therapeutic sessions at 3-week intervals in both groups. They were assessed for the remission rate (complete and partial),side effects and recurrence rate in each session and 1 month after termination of the treatments.

RESULTS: At the end of the study complete remission was achieved in 37.8% of patients in cryotherapy group and in 52.3% of patients in PDL group. This difference wasn’t statistically significant (P=0.229), though after first and second sessions of treatment complete and excellent partial remission occurred more in PDL group with significant difference (P=0.007 and P=0.021). Pain and bulla formation occurred statistically higher in cryotherapy group (P=0.002 and P=0.001). Other complications were rare in both groups.

CONCLUSION: In terms of efficacy, we couldn’t demonstrate the superiority of pulseddye laser therapy to cryotherapy in treating common warts. Both methods were safe for long-term complications but PDL was much safer for short-term complications.

Effect of KTP Laser on Surgically Resected Adenomas of Prostate

Mohammad Reza Razzaghi, Mojtaba Mohammad Hosseini, Alireza Rezaei, Iraj Rezaei, Babak Javanmard, Mohammad Mohsen Mazloomfard

Journal of Lasers in Medical Sciences, Vol. 1 No. 1 (2010), , Page 20-23

INTRODUCTION: Palmoplantar psoriasis could hardly be differentiated from chronic tylotic eczema both clinically and histologically. The most commonly used therapeutic options for palmoplantar psoriasis are long-term therapy with topical corticosteroids and local PUVA. Frequently, it is a recalcitrant disease. We investigated the efficacy and tolerability of the combination of topical calcipotriol with local UVA radiation in comparison with local PUVA therapy.

METHODS:In a total of 43 patients with palmoplantar psoriasis, 33 were given 15 sessions of local UVA radiation and topical calcipotriol and the remainder received 15 sessions of local PUVA (psoralen + UVA radiation).

RESULTS:The statistical analyses of the results showed that the effect and tolerability of both therapeutic modalities are comparable.

CONCLUSION: Combination of topical calcipotriol and local UVA radiation is an optional corticosteroid-free therapeutic modality for palmoplantar  psoriasis. It has a comparable effectiveness and tolerability with local PUVA.

Study of Long Term Effects of Laser Therapy Versus Local Corticosteroid Injection in Patients with Carpal Tunnel Syndrome

Ahmad Raeissadat, Zahra Reza Soltani

Journal of Lasers in Medical Sciences, Vol. 1 No. 1 (2010), , Page 24-30

INTRODUCTION: Carpal Tunnel Syndrome (CTS) is the most common compressive neuropathy. Several surgical and nonsurgical treatments have been proposed for this syndrome, but there is no consensus regarding the prioritization of the suggested nonsurgical treatments. The goal of this study was to compare the long term effects of laser therapy versus local corticosteroid injection in the treatment of CTS.

METHODS:During this single-blind randomized clinical trial, 65 hands with mild or moderate CTS were divided randomly into two groups. One group received local corticosteroid injection (Hydrocortisone 50 mg) and the other received low level laser therapy (20J/cm² in 11 seconds/session for each of 5 points, 775nm, 10 sessions and 3sessions/week). Furthermore, wrist splints with extension degree of 0° (neutral position) were prescribed simultaneously for 6 weeks in each group.Pain severity and electrodiagnostic measurements were compared from before to 10 months after completing each treatment. Data were analyzed with SPSS 11.5 software and parametric tests.

RESULTS: Generally, the mean age of patients was 43.9 years, duration of pain was 7.4 months, male to female ratio was 1:3, pain severity using Visual Analogue Scale (VAS) was 6.1 cm, and functional status measure was 15.5. The severity of the disease based on electrodiagnostic studies was 43.2% mild (41.2% in injection group and 45.2% in laser therapy group) and 56.8% moderate. The electrodiagnostic characteristics of the median nerve prior to treatment were included mean sensory peak latency of 4.3ms, mean sensory amplitude of 23.5μv, mean motor onset latency of 4.3ms and mean motor amplitude of 4.6mv. There was no meaningful difference between two groups regarding the demographic characteristics and electrodiagnostic measures (p>0.05). Ten months after treatments, the mean of pain severity was decreased 1.9cm in injection group and 1.7cm in laser therapy group, the mean of median sensory peak latencies was decreased 0.4ms in injection group and 0.25ms in laser therapy group and the mean of motor onset latencies was decreased 0.15ms in both groups,with no significant difference between the observed treatments variables (P>0.05). The severity of disease based on electrodiagnostic studies became 32.4% normal,23.5% mild, 41.2% moderate and 2.9% severe in the injection group and 38.7% normal,22.6% mild, 35.5% moderate and 3.2% severe in the laser therapy group. There was no meaningful difference between two groups regarding the changes in the pain severity, functional status and electrodiagnostic measures.

CONCLUSION: Low level laser therapy can be as effective as local injection in reducing pain and severity of disease (based on electrodiagnostic medicine classification) in patients with mild and moderate CTS even in long term (after 10 months).

Treatment of a Pigmented Hypertrophic Scar by Low-Level Laser Therapy (LLLT): a Case Report

Hamideh Moravvaej, Lisa Daneshvar, Mohammad Saeedi, Mohammad Reza Barzegar

Journal of Lasers in Medical Sciences, Vol. 1 No. 1 (2010), , Page 35-38

A hypertrophic scar is defined as an excess healing response that is a dilemma for physicians. Several therapies are available: intralesional corticosteroids, topical treatments, cryotherapy, surgery, radiation, silicone gel dressing and laser therapy.Pulsed-dye, Nd-Yag and CO2 lasers have been used for treatment of keloids and hypertrophic scars but recurrence is common. Recently Low-Level Laser Therapy(aluminum-gallium-arsenide (AlGaAs) Diode 980nm, red light (Mustung, KLO4,Helium Neon 630 nm) and blue light LED lasers have been used for closure of wounds. The aim of this report is to show the effectiveness of these lasers for the treatment of a hypertrophic scar on the forearm of a 40 year-old woman due to burning by gas explosion.