The efficiency of Nd:YAG laser radiation in removing debris and smear layer from prepared root
canal walls was studied. Fifty-seven human extracted single rooted anterior teeth were divided into three
groups. A group that was not lased is considered as a control group. The remaining teeth were exposed to
different laser parameters regarding laser energy, repetition rate and exposure time. For the case of the set of
parameters of 7 mJ laser energy, the cleaning was maximum at 3 p.p.s. repetition rate for 3 seconds exposure
time for, the coronal, middle and apical thirds. Above and below this energy level, there was an overdose
(melting) or under dose (no effect). Nevertheless for 10mJ laser energy case, the cleaning effi

Joining tissue is a growing problem in surgery with the advancement of the technology and more precise and difficult surgeries are done. Tissue welding using laser is a promising technique that might help in more advancement of the surgical practice. Objectives: To study the ability of laser in joining tissues and the optimum parameters for yielding good welding of tissues. Methods: An in-vitro study, done at the Institute of Laser, Baghdad University during the period from October 2008 to February 2009. Diode and Nd-YAG lasers were applied, using different sessions, on sheep small intestine with or without solder to obtain welding of a 2-mm length full thickness incision. Different powers and energies were used to get maximum effect. Re

This paper presents the effect of relativistic and ponderomotive nonlinearity on cross-focusing of two intense laser beams in a collisionless and unmagnetized plasma. It should be noted here that while considering the self-focusing due to relativistic electron mass variation, the electron ponderomotive density depression in the channel may also be important. Therefore/these two nonlinearties may simultaneously affect the self-focusing process. These nonlinearities depend not only on the intensity of one laser but also on the second laser. Therefore, one laser beam affects the dynamics of the second beam and hence the process of cross-focusing takes place. The electric field amplitude of the excited electron plasma wave (EPW) has been cal

Acne scars are one of the most common problems following acne vulgaris. Despite the extensive list of available treatment modalities, their effectiveness depends upon the nature of the scar. Ablative lasers had been used to treat acne scars; one of them is the fractional CO2 laser. The aim of this study is to evaluate the outcome of fractional CO2 laser in the treatment of acne scars. Methods: Since January 2010 to June 2013, using 10600 nm fractional CO2 laser beams, the acne scar of 400 patients, 188 males and 212 females, mean age of 34 years, have been treated and classified according to severity into four grades following Goodman and Baron classification. Each patient underwent 3-5 sessions once monthly. The mean laser exposure time

The nonlinear refractive index and the nonlinear absorption coefficient of unmodified and functional poly(methyl methacrylate) PMMA films were studied before and after the addition of the filler by the z-scan technique, using a Q-switched Nd:YAG laser at two wavelengths: 532 nm and 1064 nm, and at three input energies (13, 33 and 53) mJ. Both linear and nonlinear refractive indices and absorption coefficients of polymer films were studied by using UV-VIS spectrophotometer. The results show that the creation of functional PMMA from unmodified PMMA will increase the nonlinear optical properties in the functional PMMA/copper matrix more than in the unmodified PMMA/copper matrix. Hence, the functional PMMA appears promising as a useful third

The purpose of this study is to demonstrate a simple high sensitivity vapor sensor for propanol ((CH3)2CHOH). A free space gap was employed in two arms of a Mach-Zehnder interferometer to serve as the sensing mechanism by adding propanol volume (0.2, 0.4, 0.6, 0.8, and 1) ml and to set the phase reference with a physical spacing of (0.5, 1, 1.5, and 2) mm. The propagation constant of transmitted light in the Mach-Zehnder interferometer’s gap changes due to the small variation in the refractive index inside sensing arm that will further shift the optical phase of the signal. Experimental results indicated that the highest sensitivity of propanol was about 0.0275 nm/ml in different liquid volume while highest phase shift was 0.182×103 i

The aim of the study was to evaluate the efficacy of diode laser (λ=940 nm) in the management of gingival hyperpigmentation compared to the conventional bur method. Materials and methods: Eighteen patients with gingival hyperpigmentation were selected for the study with an age between 12-37 years old. The site of treatment was the upper gingiva using diode laser for the right half and the conventional method for the left half. All patients were re-evaluated after the following intervals: 3 days, 7 days, 1 month and 6 months post-operation. Pain and functions were re-evaluated in each visit for a period of 1 day, 3 days and 1 week post-operation. Laser parameters included 1.5 W in continuous mode with an initiated tip (400 μm) placed in

الهدف: الهدف من البحث الحالي هو كشف الأنياب المنطمرة في الشدق العلوي باستخدام ل يزر الدايود ) 810 + 980 ( نانومتر) في مقارنة الأنياب المنطمرة حنكي ا اعتماد ا على هذه العوامل الألم، الورم، زمن الشفاء(. المقدمة: يوفر ليزر الصمام الثنائي( 810 + 980) اختراق ا عميق ا للأنسجة الرخوة وتخثر الدم وتجلط الدم بشكل ممتاز ولديه الحد الأدنى من التفاعل مع أنسجة الأسنان الصلبة .
المواد والطرق: جميع المرضى الذين يعا

Abstract: Background: Optical biosensors offer excellent properties and methods for detecting bacteria when compared to traditional analytical techniques.  It allows direct detection of many biological and chemical materials.  Bacteria are found in the human body naturally non-pathogenic and pathologically, as they are found in other living organisms.  One of these bacteria is Escherichia coli (E. coli) which are found in the human body in its natural and pathogenic form. E.coli bacteria cause many diseases, including Stomach, intestines, urinary system infections, and others. The aim of this study: is sensing and differentiation between normal flora and pathogenic E.coli. Material and method:

تطوير مستشعر لقياس التغير في معامل الانكسار للمحيط باستخدام تقنية مستشعر الألياف غير النواة على شكل حرف (D) .يتكون هذا المستشعر من قطعة من الألياف غير النواة ) CF ( ملحومة بين ليفين أحادي النمط ) SMF (. تم تلميع منتصف طول الألياف غير النواة باستخدام عجلة طحن لتقليل القطر من جانب واحد، مما أدى إلى إنشاء مقطع عرضي على شكل حرف D .تم اختبار أداء مستشعر DSCF باستخدام تركيزات مختلفة من محاليل كلوريد الصوديوم ( NaCl)، حيث تتراوح

Random laser gain media is synthesized with different types of dye at the same concentration (1×10^-3 M) as an active material and silicon dioxide NPs (silica SiO₂) as scatter centers through the Sol-Gel technique. The prepared samples are tested with UV–Vis spectroscopy, Fluorescence Spectroscopy, Field Emission Scanning Electron Microscopy (FESEM), and Energy Dispersive X-ray Diffraction (EDX). The end result demonstrates that doped dyes with silica nanoparticles at a concentration of 0.0016 mol/ml have lower absorbance and higher fluorescence spectra than pure dyes. FESEM scans revealed that the morphology of nanocrystalline silica is clusters of nano-sized spherical particles in the range (25-67) nm. It is con

توفر طرق طبة المسحوق, بما في ذلك الصهر بالليزر الانتقائي و تنوعا كثيرا في كل من عمليات التصميم والتصنيع. ومع ذلك , فأن القيد الحالي لهذه الطريقة يكمن في قدرتها على انتاج أجزاء من مادة واحدة. بالنسبو لمتطلبات المواد المتعددة المعقدة مثل عمليات الطلاء. تتضمن الحلول المثالية تكاملا مخصصا للمواد المتنوعة المطلوبة للتحكم في عملية الذوبان والتصلب داخل واجهة المعادن المختلفة. في هذه الدراسة, تم أنشاء نموذج ديناميك

الهدف : الأسباب الأكثر شيوعا في فشل ارتباط الوتد الليفي هو الترميم الغيركافي والازاحه. التركيب السطحي للوتد الليفي يتأثر
بواسطة إشعاع الليزر وقد يعزز من قوة التصاقه. في هذه الدراسة الاستطلاعية نناقش تأثيرليزر Er,YAG وليزر Er,CR:YSGG على سطح الوتد الليفي وقوة التصاقه بالاسمنت الراتنجي في الأسنان المعالجة لبيا .
الطرق : تم بحث شامل في مقالات محرك كوكل و PubMed و Medline و Web of Science نشرت من 2013 إلى
2023 و

The aim of this study is to investigate the ability of malachite green (MG) combined with 650nm diode laser to kill Candida albicans and to spectrally study the MG photodegradation after photodynamic therapy (PDT) spectrally. Cultures of Candida albicans were exposed to 40mW, 650 nm diode laser in the absence of MG. In PDT group, the MG was added to the Candida suspension for 5 min then exposed to diode laser for (5, 10, 15, 20) min at power density of 0.59W/cm2. The absorption spectrum of the photosensitized fungal suspension was obtained. The data were submitted to T-test (p<0.05). A 650nm diode laser in the presence of MG reduced the number of CFU/ml in 98.4%. Laser with 650nm alone and MG alone did not reduce significantly the num

The present study was conducted with a view to determine whether focal laser therapy result in visual recovery and regression of macular edema in patients with non proliferative diabetic retinopathy and maculopathy ,and whether combined focal and scatter laser therapy in patients with proliferative diabetic retinopathy and maculopathy results in visual recovery ,regression of macular edema and regression of the risk factors. In the present work, a frequency doubled Nd: YAG laser was used for the treatment of diabetic retinopathy. The study evaluates 41 eyes of 33 diabetic patients both with Insulin Dependent Diabetes Mellitus IDDM, (n=16) and Non Insulin Dependent Diabetes Mellitus NIDDM, (n=17) with diabetic retinopathy divided into two

Objectives: This study aims to detect the penetration of the AH Plus sealer in the coronal third using a pulsed (Er, Cr: YSGG) laser with a short pulse duration when the SWEEPS was used to activate irrigation (Shock wave Enhanced Emission Photoacoustic Streaming). Methods: A total of 28 single-rooted mandibular premolars. The laser used is pulsed Er, Cr: YSGG assisted by the SWEEPS technique. There are four groups of samples (n = 7) for each: Group 1: Traditional syringe irrigation using 5 mL of 17% EDTA. Group 2: passive ultrasonic irrigation using mL of 17% EDTA. Group 3: Er, Cr: YSGG laser-induced SWEEPS using 5 mL of 17% EDTA. Group 4: Er, Cr: YSGG laser-induced SWEEPS using 5 mL of 5.25% NaOCl and 5

This work examines the beam squint effects of quantum-based carbon nanotube (CNT) antenna arrays for optical plasmonic communication systems functioning within the 300 THz to 700 THz frequency spectrum. The distinctive quantum confinement characteristics of carbon nanotubes (CNTs), together with surface plasmon polariton (SPP) interactions, result in notable frequency-dependent phase shifts, causing beam squint errors in phased array systems. Simulation findings indicate that at 300 THz, a CNT array with an inter-element spacing of λ/2 (500 nm) has a beam squint of 0.2° per 100 THz bandwidth. As the frequency ascends to 700 THz, the beam squint effect amplifies, reaching 0.8° per 100 THz as a result of heightened plasmonic dispersion

The hole transport layers are critical components of organic conductor-based devices. The metal nanoparticles (NPs) are excellent materials for this purpose. This paper describes the preparation of silver nanoparticles (Ag NPs) using a laser method, which were then mixed with the organic polymer poly(3-hexylthiophene) (P3HT) at different concentrations (0.1, 0.3, and 0.4 wt%). The structural morphology, structure, and optical properties of the new nanocomposite were examined using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), and UV-Vis spectroscopy. The XRD data showed that the created Ag NPs have a crystal structure, with the strongest peaks seen at angles of 38.1°, 44.3°

In this study, laser-induced breakdown spectroscopy (LIBS) was used to analyze the plasma generated from a Zn:Cu alloy (x = 0.9) using a Nd:YAG laser at 1064 nm. Plasma was generated at different laser pulse energies ranging from 400 to 800 mJ. The electron temperature (Te) was determined using the Boltzmann plot method, while the electron number density (ne) was calculated using Stark broadening. Other plasma parameters were also evaluated, including plasma frequency (fp), Debye length (λD), and Debye number (Nd). The results showed that Te increased from 0.846 eV at 400 mJ to 0.906 eV at 800 mJ, and ne increased from 1.000 × 10¹⁸ cm⁻³ to 1.121 × 10¹⁸ cm⁻³. Plasma frequency increased from 898.000 × 1010 Hz to 950,868 ×

Abstract :H.pylori is an important cause of gastric duodenal disease, including gastric ulcers, Mucosa-associated lymphoid tissue (MALT), and gastric carcinoma. biosensors are becoming the most extensively studied discipline because the easy, rapid, low-cost, highly sensitive, and highly selective biosensors contribute to advances in next-generation medicines such as individualized medicine and ultrasensitive point-of-care detection of markers for diseases.  Five of ten patients diagnosed with H.pylori ranging in age from 15–85 participated in this research. who [gastritis, duodenitis, duodenal ulcer (DU), and peptic ulcer (PU)] Suspected H.pylori colonies w

Abstract: Background: High percentage of diabetes patients complain from post extraction hemorrhage. Many types of hemostatic materials are used to stop bleeding after teeth extraction: diode lasers are good hemostatic agents owing to their highly absorption by hemoglobin therefore they are used in soft tissue procedures with relatively no effects on dental hard tissues due to their poorly absorption by water and hydroxyapatite. Objectives: The aim of this study is to evaluate the efficiency of diode laser to assist the clot formation after tooth extraction for type II diabetes patients with minimum temperature elevation to prevent periodontal destruction. Materials and methods: From 12 type II diabetes patients (7 males and 5 females wi

Striae distensae SD or stretch mark are frequent skin lesion that cause considerable aesthetic concern. The 1064nm long pulsed Nd:YAG Laser has been used to promote an increase in dermal collagen and is known to be a Laser that has a high affinity to vascular chromphores. Also by using fractional CO₂ Laser 10600nm as an effective modality in treatment of striae distensae SD. It works to stimulate fibroblast and enhance Collagen formation, which is important for newly generated skin tissue.

Objectives: This study aims to verify the efficacy of long pulsed Nd: YAG Laser (1064nm) in the treatment of immature striae distensae (SD) and the efficacy of C0₂ fractional Laser (10600nm) in treatment o

The objective of this in vivo study is to investigate the effects of 337.1 nm pulsed N2 laser on cellular immune response represented by lymphocyte transformation capacity and phagocytosis activity in laboratory animals. The samples include 60 adult male BALB/c mice, were divided into control group and experimental groups. The experimental groups were divided into two main groups according to the time period after N2 laser irradiation. Each group was divided into 9 subgroups which exposed to N2 laser radiation at different values of pulse repetition rates and exposure times. The results of immunological tests demonstrated that the exposure to 180 J/cm2 of N2 laser radiation induce adverse effect to cellular immune response. The results o

Background: Crown preparation of vital teeth involve the removal of a sound tooth structure, and when enamel removed this lead to exposed dentin with an   increase in the number of open dentinal tubules also the diameter of dentinal tubules will increase, furthermore lead to increase movement of fluids inside the tubules all that causes post preparation sensitivity. The aim of this study is to evaluate the effect of desensitizing by Er:Cr:YSGG laser on shear bond strength of prepared tooth and resin cement. Materials and methods: Thirty sound maxillary premolars, grouped into three groups(n=10). Group A is the control group, group B irradiated by Er:Cr:YSGG laser with (0.25 W, 20 Hz, 1

The main objective of this study is to determine the suitable excitation wavelengths for
urine components reaching to select the suitable lasers to execute the auto fluorescence due to their
high intensities. The auto fluorescence was measured at 305, 325 and 350 nm excitation wavelengths
for eleven urine samples which were also analyzed by conventional methods (chemical and
microscopic examination). Data manipulation using Matlab package programming language showed
that urine sample with normal chemical and biological components have emission peaks which are
different from the infected urine samples. Despite the complexity of the composition of urine,
fluorescence maxima can be observed. Most likely, the peaks obser

                                                                                                                الحاجة الى مصادر الفوتون المنفرد في منظومات توزيع المفتاح الكمي ادت الى استخدام النبضات الضعيفة المتشاكهة والتي لها توزيع بواسون. لكي يتم منع هجمات التنصت, يجب الحفاظ على معدل لعدد فوتونات قليل ومعروف للشركاء الموثوقين.عدا ذلك فأن قيمة معدل عدد الفوتونات لا يمكن ايجادها بدق

Background: preparation of root canals is an important step in root canal treatment. Mechanical instrumentation of root canals cause an irregular layer of debris, known as the smear layer. As a result, several studies reported that preferring the removal of the smear layer. Objective: To study the influence of the energy (100 mJ) of Erbium, Chromium: Yttrium Scandium Gallium Garnet (Er,Cr:YSGG) laser at short pulse duration (60 μs)  on smear layer removal of apical third after using Photon induced photoacoustic streaming technique. Materials and methods: Eighteen straight single-rooted mandibular premolars were used. The roots length were uniform to 14mm from the anatomic apex and

Background: Pyogenic granuloma is a hyperplastic benign tumor. The most common intra-oral site is marginal gingiva. It is often occurred in the second decade of life, it has a strong tendency to recur after simple excision.

The aim of study: to evaluate the therapeutic advantages of diode laser (810-980 nm) in intraoral Pyogenic granuloma management.

Materials and method: A total of 28 patients (14 men and 14 females) were enrolled in this study and had their pyogenic granuloma surgically removed using a diode laser. All of the patients were given local anesthetic and went through the identical surgical procedure (cartridge containing 1 percent lidocaine with epinephrine 1:

Abstract: The use of indirect, all-ceramic restorations has grown in popularity among dentists. Studies have demonstrated that for indirect ceramic restorations to be effective over time, cement and ceramic must be bonded in a stable manner. Chemical, mechanical, and laser irradiation are among the methods used to precondition ceramic surfaces in order to increase bond strength.The objective of the study: This study was performed to investigate the roughness values and surface topography of lithium disilicate glass-ceramic treated with conventional methods and different Er,Cr:YSGG, and fractional CO₂ laser conditioning parameters.Material and methods:<

Abstract: Despite the distinct features of the continuous wave (CW) Terahertz (THz) emitter using photomixing technique, it suffers from the relatively low radiation output power. Therefore, one of effective ways to improve the photomixer emitter performance was using nanodimensions electrodes inside the optical active region of the device. Due to the nanodimension sizes and good electrical conductivity of silver nanowires (Ag-NWs), they have been exploited as THz emitter electrodes. The excited surface plasmon polariton waves (SPPs) on the surface of nanowire enhances the incident excitation signal. Therefore, the photomixer based Ag-NW compared to conventional one significantly exhibits higher THz output signal. In thi