Efficacy of the Treatment of Plantar Warts Using 1064 nm Laser and Cooling

Cutaneous plantar warts may be treated using several optional methods, with the use of laser surgery having increased in the last few years. This work examined the efficacy of laser treatment combined with simple cooling to reduce pain. The cure rate was approximately 84%. There were no significant differences in the efficacy of treatment for different viral genotypes. The laser parameters were 500 msec pulses, 30 W of power, and a fluence of 212 J/cm2 delivered in up to four sessions. Successful treatment was achieved after an average of 3.6 sessions.

Pre-calculated relevant Nd: YAG laser parameters for optimized varicose veins treatment

Full clearance of enlarged veins, without side effects, had always been the ultimate dream of patients. Varicose veins’ treatment protocols were not very decisive and mostly associated with some side effects. The aim of this work is to demystify the exact dose of laser parameters; namely fluence and pulse duration, to successfully treat enlarged blood vessels in face, legs and arms without side effects. This necessitated the calculation of exact temperature rise of the targeted tissue before laser irradiation. The pre-calculated laser parameters required, for successful treatment, without side effects were tested to achieve optimum clinical results; using 1064nm pulsed Nd: YAG lasers for all skin photo types. For this work, two values of spot size (5mm and 3mm), variable pulse duration (15-30 ms), variable fluences (110-190 J/cm2) and variable skin cooling temperature (3-18 °C) were used. Pre and post-cooling were found necessary to ensure positive results and minimal discomfort.

Fibroblasts Adhesion to Laser-Modified Titanium Surfaces—A Systematic Review

Objective: Laser treatment has been recently introduced in many fields of implant dentistry. The systematic review tried to address the question: “How does laser modification of titanium surface influence fibroblast adhesion?”. Methods: An electronic search of the PubMed and Scopus databases was performed. The following keywords were used: (laser) AND (fibroblast) AND (titanium) AND (implant OR disc) AND (proliferation OR adhesion). Initially, 136 studies were found. Ten studies met the inclusion criteria and were included in the review. All studies chosen to be included in the review were considered to have a low risk of bias. Results: Studies included in the review varied with laser parameters or ways of observing fibroblast behavior. Studies showed that fibroblasts tend to take different shapes and create extensions on modified surfaces and that their metabolic activity is more intense. One study concentrated on laser application and showed that three-directional laser application is the most successful in terms of fibroblast adhesion. Studies which concentrated more on laser parameters showed that too low energy density (lower or equal to 0.75 J/cm2) does not influence fibroblast adhesion. Increasing the energy density over 0.75 J/cm2 causes better cell adhesion of fibroblasts to the laser-modified sample. One included study focused on increasing titanium surface wettability, which also positively influenced cell adhesion. Conclusion: The studies included in the review proved a positive effect of laser-modified titanium surfaces on fibroblast adhesion. However, the application of an appropriate laser energy dose is crucial.

EFFECTS OF LOW-LEVEL LASER THERAPY ON LIVER REGENERATION AND THE LASER PARAMETERS EMPLOYED

Low-level laser therapy has various biological effects; one of them is tissue regeneration. Its application in the liver of rats after partial hepatectomy to promote liver regeneration has recently been studied. The aim of this article was to review the recent studies on the effects of low-level laser therapy on rat liver regeneration after partial hepatectomy and the laser parameters used. A review of recent relevant literature was performed in Pubmed, Scielo, Medline and Bireme databases. Articles about the application of low-level laser therapy on hepatic regeneration were included. Articles with hepatic regeneration in the presence of pathologies were not included. Nine studies were found matching the study criteria. In most studies, low-level laser therapy promoted liver regeneration after partial hepatectomy, without further damage to the remaining liver. Not all laser parameters necessary for the reproducibility of the study were described by all authors. The therapeutic use of low-level laser therapy in liver regeneration can be promising, however, as liver is a vital organ and the laser application is intraoperative, future studies are needed. The parameters used must be properly described and standardized to allow the reproducibility of the study, so that a therapeutic window can be defined and its clinical use can be considered. It is also essential to clarify the mechanisms by which the laser promotes liver regeneration, to guarantee its safety and therapeutic efficacy.

Developing an Empirical Relationship to Predict the Wear Characteristics of Ni-Based Hardfaced Deposits on Nuclear Grade 316LN Austenitic Stainless Steel

Using the nickel-based Colmonoy 5 hardfacing alloy, components made of austenitic stainless steel (ASS) used in nuclear power plants can be hardfaced. Hardfacing is the process of applying complex and wear-resistant materials to substrates that require abrasion resistance. The tribological characteristics of a reactor-grade material NiCr-B hardfaced deposit were studied and reported in this paper. Hence, in this investigation, an effort has been made to develop empirical relationship to predict weight loss of laser hardfaced Ni-based alloy surface incorporating laser parameters using statistical tools such as design of experiments (DoE) and analysis of variance (ANOVA). The developed empirical relationship can be effectively used to trail the weight loss (wear resistance) of laser hardfaced nickel alloy surfaces by altering laser parameters. This method has proven very effective. A power of 1300 W, powder feed rate of 9 g/min, travel speed of 350 mm/min, and defocusing distance of 32 mm were all combined to achieve a minimum weight loss of 0.0164 grams.

Thermal effect of a 445 nm diode laser on five dental implant systems: an in vitro study

The purpose of this in vitro study was to assess the thermal effect of the 445 nm diode laser on five dental implant systems. In an ailing implant protocol, five commercial dental implant systems were subjected to 445 nm diode laser energy at different wattages [W], exposure times, and modes (continuous wave [CW] vs. pulsed and contact vs. non-contact) of laser beam delivery. Scanning electron microscopy (SEM) allowed the evaluation of irradiated implant surfaces. A total of 2880 temperature response curves were recorded. The 445 nm wavelength caused temperature increases of more than 10 °C at or above the 0.8 W power level working in CW mode for 5 s and in pulsed mode at 3 W for 20 s with 10% duty cycle. Highest rises in temperature were seen in the Straumann Pure ceramic implant, lowest in the Ankylos system. SEM analysis revealed no surface alteration in all systems in non-contact mode. The applied laser is not inherently safe for the decontamination of ailing implants. From the results of this study it was concluded that different dental implant materials and geometries show different temperature response curves when subjected to 445 nm diode laser energy. Clinicians ought to be aware of this. Therefore, manufacturers of laser devices should provide implant-specific laser parameters for the decontamination process. However, both laser irradiation systems can prevent harmful rises in temperature and surface alteration when used at moderate laser parameters.