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Wednesday, August 27, 2008
 Latest
Laser Surgery Medical and Health News Headlines
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Laser Surgery Medical and Health News Headlines
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All Recent Laser Surgery Medical News Headlines |
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Effect of equal daily doses achieved by different power densities of low-level laser therapy at 635 nm on open skin wound healing in normal and corticosteroid-treated rats
Abstract Optimal parameters of low-level laser therapy (LLLT) for wound healing are still discussed. Hence, our study was aimed to
compare effects of different power densities of LLLT at 635 nm in rats. Four, round, full-thickness, skin wounds were made
on the backs of 48 rats that were divided into two groups (non-steroid laser-treated and steroid laser-treated). Three wounds
were stimulated daily with a diode laser (daily dose 5 J/cm2) each with different power density (1 mW/cm2, 5 mW/cm2, and 15 mW/cm2), whereas the fourth wound served as a control. Two days, 6 days, and 14 days after surgery, eight animals from each group
were killed and samples were removed for histological evaluation. In the non-steroid laser-treated rats, significant acceleration
of epithelization and collagen synthesis 2 days and 6 days after surgery was observed in stimulated wounds. In steroid laser-treated
rats, 2 days and 14 days after surgery, a decreased leucocyte/macrophage ratio and a reduction in the area of granulation
tissue were recorded, respectively. In conclusion, LLLT, by the method we used, improved wound healing in the non-steroid
laser-treated rats, but it was useless after corticosteroid treatment.
Content Type Journal ArticleCategory Original ArticleDOI 10.1007/s10103-008-0604-9Authors
Peter Gál, Pavol Jozef Šafárik University Department of Medical Biophysics Trieda SNP 1 040 11 Košice Slovak RepublicMichal Mokrý, Pavol Jozef Šafárik University Department of Medical Biophysics Trieda SNP 1 040 11 Košice Slovak RepublicBoris Vidinský, Pavol Jozef Šafárik University Department of Medical Biophysics Trieda SNP 1 040 11 Košice Slovak RepublicRóbert Kilík, Pavol Jozef Šafárik University and Louise Pasteur Faculty Hospital 1st Department of Surgery Košice Slovak RepublicFilip Depta, Pavol Jozef Šafárik University Department of Medical Biophysics Trieda SNP 1 040 11 Košice Slovak RepublicMagdaléna Harakaľová, Pavol Jozef Šafárik University Department of Medical Biophysics Trieda SNP 1 040 11 Košice Slovak RepublicFrantišek Longauer, Pavol Jozef Šafárik University Department of Forensic Medicine Košice Slovak RepublicŠtefan Mozeš, Slovak Academy of Sciences Institute of Animal Physiology Košice Slovak RepublicJán Sabo, Pavol Jozef Šafárik University Department of Medical Biophysics Trieda SNP 1 040 11 Košice Slovak Republic
Journal Lasers in Medical ScienceOnline ISSN 1435-604XPrint ISSN 0268-8921 (Source: Lasers in Medical Science)...
POSTED 08/21/2008 at 04:23 AM --
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Microleakage of glass ionomer formulations after erbium:yttrium–aluminium–garnet laser preparation
Abstract The aim of this study was to investigate the microleakage in class V cavities restored with four conventionally setting glass
ionomers (CGIs) and one resin-modified glass ionomer (RMGI) following erbium:yttrium–aluminium–garnet (Er:YAG) laser or conventional
preparation. Four hundred class V cavities were assigned to four groups: A and B were prepared by an Er:YAG laser; C and D
were conventionally prepared. In groups B and D, the surface was additionally conditioned with Ketac conditioner. Each group
was divided into five subgroups according to the glass ionomer cement (GIC) used: groups 1 (Ketac Fil), 2 (Ketac Molar), 3
(Ionofil Molar), 4 (Ionofil Molar Quick) and 5 (Photac Fil Quick). After thermocycling, a 2% methylene blue solution was used
as dye. Scanning electron microscope (SEM) photographs were taken to show the conditioner’s effect. Complete marginal sealing
could not be reached. PhotacFil showed less microleakage than the conventionally setting glass ionomer cements (CGICs) investigated.
Conditioning laser-prepared cavities did not negatively influence microleakage results except for Ionofil Molar Quick.
Content Type Journal ArticleCategory Original ArticleDOI 10.1007/s10103-008-0598-3Authors
Katleen I. M. Delmé, Ghent University Department of Operative Dentistry and Endodontology, Ghent Dental Laser Center, Dental School, Ghent University Hospital De Pintelaan 185/P8 9000 Gent BelgiumPeter J. Deman, Rink 26 Sint-Pieters-Leeuw BelgiumMieke A. A. De Bruyne, Ghent University Department of Operative Dentistry and Endodontology, Ghent Dental Laser Center, Dental School, Ghent University Hospital De Pintelaan 185/P8 9000 Gent BelgiumSamir Nammour, University of Liège Department of Dental Sciences, Faculty of Medicine Liège BelgiumRoeland J. G. De Moor, Ghent University Department of Operative Dentistry and Endodontology, Ghent Dental Laser Center, Dental School, Ghent University Hospital De Pintelaan 185/P8 9000 Gent Belgium
Journal Lasers in Medical ScienceOnline ISSN 1435-604XPrint ISSN 0268-8921 (Source: Lasers in Medical Science)...
POSTED 08/21/2008 at 04:23 AM --
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Adhesives bonded to erbium:yttrium–aluminum–garnet laser-irradiated dentin: transmission electron microscopy, scanning electron microscopy and tensile bond strength analyses
Abstract The aim of this in vitro study was to investigate the effect of erbium:yttrium–aluminum–garnet (Er:YAG) laser irradiation
on dentinal collagen by transmission electron microscopy and to analyze the resin–dentin interface by scanning electron microscopy.
A tensile bond strength test was also applied. Specimens from 69 sound human third molars were randomly divided into three
groups: control (no laser), and two irradiated groups, laser 250 (250 mJ/2 Hz) and laser 400 (400 mJ/4 Hz). Then, specimens
were restored with two adhesive systems, an etch-and-rinse or a self-etch system. Although ultrastructural examination showed
a modified surface in the irradiated dentin, there was no statistical difference in bond strength values between the laser
groups and controls (P < 0.05). In conclusion, the use of Er:YAG laser for ablating human dentin did not alter the main adhesion parameters when
compared with those obtained by conventional methods, thus reinforcing its use in restorative dentistry.
Content Type Journal ArticleCategory Original ArticleDOI 10.1007/s10103-008-0600-0Authors
Andreia Cristina Bastos Ramos, University of Fortaleza School of Dentistry Fortaleza CE BrazilMarcella Esteves-Oliveira, University of São Paulo Special Laboratory of Lasers in Dentistry, Department of Restorative Dentistry, School of Dentistry 05508-900 São Paulo SP BrazilVictor E. Arana-Chavez, University of São Paulo Laboratory of Mineralized Tissue Biology, Department of Cell and Developmental Biology, Institute of Biomedical Sciences 05508-900 São Paulo SP BrazilCarlos de Paula Eduardo, University of São Paulo Special Laboratory of Lasers in Dentistry, Department of Restorative Dentistry, School of Dentistry 05508-900 São Paulo SP Brazil
Journal Lasers in Medical ScienceOnline ISSN 1435-604XPrint ISSN 0268-8921 (Source: Lasers in Medical Science)...
POSTED 08/21/2008 at 04:23 AM --
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A clinical comparison of topical piroxicam and emla cream for pain relief and inflammation in laser hair removal
Abstract The aim of this study was to compare the efficacy of topical piroxicam and EMLA cream on pain control and subsequent inflammation
in neodymium:yttrium–aluminum–garnet (Nd:YAG) 1,064 nm laser hair removal in female volunteers. Fifty female volunteers were
enrolled in this prospective, randomized, double-blind, clinical study over a 6-month period. Patients were randomly assigned
to receive topical piroxicam as group Piroxicam or EMLA cream as group EMLA. Topical analgesics were applied to the treatment
sites for 60 min. The pain scores [on a visual analog scale (VAS)] and side effects were recorded before the hair removal,
during the hair removal, at the end of the hair removal, and 1 h, 2 h and 24 h after the hair removal. Patients’ characteristics
and the treatment settings of the Nd:YAG 1,064 nm laser were similar in the two groups. The pain scores (VAS) were similar,
and satisfaction was high in both groups after the hair removal. The number of blanching and erythema episodes were significantly
higher in group E than in group P (P < 0.001). Inflammatory side effects were less frequent in group P than in group E after the procedure (P < 0.001). This study showed that topical piroxicam and EMLA provided adequate and similar pain relief after Nd:YAG 1,064 nm
laser hair removal in female volunteers. Topical piroxicam was associated with fewer inflammatory side effects than was EMLA
cream, because of its anti-inflammatory effect after the procedure.
Content Type Journal ArticleCategory Original ArticleDOI 10.1007/s10103-008-0599-2Authors
Semra Akinturk, Bahat Hospital Department of Dermatology Istanbul TurkeyAhmet Eroglu, Karadeniz Technical University Department of Anesthesiology, Faculty of Medicine 61080 Trabzon Turkey
Journal Lasers in Medical ScienceOnline ISSN 1435-604XPrint ISSN 0268-8921 (Source: Lasers in Medical Science)...
POSTED 08/21/2008 at 04:23 AM --
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Pulsed co2-laser excitation of 03/02 mixtures at pressures from 0.16 to 1.20 bar
An investigation is presented of the transient vibrational excitation of O3 in the collision dominated
regime initiated by pulsed CO2-laser radiation. IR-UV-double resonance experiments and measurements
of the absorbance for the CO2-laser lines 9P18, 20, and 22 were carried out. Mixtures of O3 (p=17 mbar)
with 02 were investigated at pressures of 160 mbar ≤Pmixt≤1200 mbar and laser fluences of 0.10 J/cm2≤Fin< 2 J/cm2
. The results are interpreted by numerical simulations in terms of a comprehensive
excitation/relaxation model based upon SSH-theory. Concerning the evolution of the excitation, simulated
transients of the UV-absorbance compare well with the corresponding observed signals. The
saturation of the absorbing O3-transitions is demonstrated by the measured fluence dependence of the
absorption coefficient at the laser wavelengths. The extent of the 03-excitation can be deduced according
to the model from the maximum vibrational temperature Tm reached in the v1- and v3-oscillators. Tm
accessible via the UV-transients and also via the absorbed laser energy in the case of slow relaxation at 160
160mbar≤Pmixt≤340 mbar. In this range both techniques result in the same values for Tm. The experimental
and the corresponding simulated Tm depend exponentially on the laser fluence (Tm =const . F¯in0.3)
provided Tm>400K being also confirmed up to Pmixt=1200 mbar by the observed UV-transients. (Source: Laser Chemistry)...
POSTED 08/17/2008 at 12:41 PM --
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Uv photoablation of atherosclerotic lesions. application in cardiology
Various methods for the ablation of the atherosclerotic material that fills the coronary arteries are under
investigation. Among them laser coronary angioplasty is one of the most promising. In this paper we show
that the XeCl excimer laser (308 nm) offers many advantages which make it appear as a rather good tool.
In vitro studies demonstrate the ability of precise control of the UV photoablation process, there is no
thermal damage and the risk of perforation is reduced. A suitable laser-fiber optic delivery system has
been developed and the results of the first in vivo procedures are very encouraging. (Source: Laser Chemistry)...
POSTED 08/17/2008 at 12:41 PM --
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Infrared laser photochemistry of trans-1, 2-dichloroethylene. evidence for a ci atom chain reaction
The TEA-CO2 laser induced reaction of trans-l,2-dichloroethylene (TDCE) was investigated at 925
cm-1. The laser radiation was focused to yield beam waist fluences of approximately 125 J cm-2. The
major reaction product was cis-1, 2-dichloroethylene (CDCE), with a few per cent of chloroacetylene, and
minor amounts of acetylene, dichloroacetylene, chloroethylene and an unidentified C4 compound also
being formed. The reaction of pure TDCE was studied as a function of number of laser pulses and total
pressure (0.02 to 5 torr). Some experiments were also done with added ethane (20%) and propane (2%).
Evidence was obtained that the formation of the cis isomer occurs via two mechanisms, (1) a unimolecular
isomerization, and (2) a CI atom chain reaction. The results are consistent with laser induced decomposition
of TDCE occurring through the three lowest energy channels: unimolecular structural isomerization
(57.4 kcal/mol); molecular HCI elimination (69 kcal/mol); and C-CI bond scission (89 kcal/mol). (Source: Laser Chemistry)...
POSTED 08/17/2008 at 12:41 PM --
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Solvation dynamics studied by picosecond fluorescence:
microscopic reorientation and longitudinal relaxation of the solvent
The dynamics of the Time-Dependent Fluorescence Shift (TDFS) of a rigid polar excited probe dissolved
in alcohol solvents at different temperatures have been studied by picosecond time-resolved spectroscopy.
The results are compared to previously published results on well characterized polar systems. These
results show that solvation dynamics in such systems are strongly scaled by the microscopic (singleparticle)
reorientation time τM of the solvent molecules and/or by the (macroscopic) longitudinal
relaxation time τL of the solvent. The key point governing this scaling is the relative interaction between
the solvent molecules and the probe compared to the interaction between the solvent molecules. It is also
shown that specific interactions, such as hydrogen bonded-complex formation, may play an important
role. (Source: Laser Chemistry)...
POSTED 08/17/2008 at 12:41 PM --
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Laser induced fluorescence
Laser induced fluorescence (LIF) has become a common detector of atoms and molecules allowing to
determine their internal state distributions. In this paper we mention the advantages of both kinds of
lasers, cw or pulsed. We review some aspects of the LIF process, such as saturation or polarization effects,
which could alter the results if they were not taken into account. We also indicate how LIF can be used to
measure relaxation times and thus rate constants of the relaxation processes: some experimental results
obtained in our laboratory illustrate these points. (Source: Laser Chemistry)...
POSTED 08/17/2008 at 12:41 PM --
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Visible lasers were better than invisible lasers in accelerating burn healing on diabetic rats
Photomedicine and Laser Surgery , Vol. 0, No. 0: 1-4.
Abstract Objective: This study was designed to compare the efficacy of low-power visible with invisible lasers for accelerating burn healing on diabetic rats. Background Data: Low-level laser therapy (LLLT) has been used in a number of diabetic animal ... (Source: Photomedicine and Laser Surgery)...
POSTED 08/15/2008 at 10:02 PM --
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In vivo evaluation of laser fluorescence performance using different cut-off limits for occlusal caries detection
In vivo evaluation of laser fluorescence performance using different cut-off limits for occlusal caries detection
Content Type Journal ArticleCategory ErratumDOI 10.1007/s10103-008-0601-zAuthors
Michele Baffi Diniz, São Paulo State University (UNESP) Department of Pediatric Dentistry, Araraquara School of Dentistry Av. Humaitá 1680 14801–903 Araraquara SP BrazilJonas de Almeida Rodrigues, São Paulo State University (UNESP) Department of Pediatric Dentistry, Araraquara School of Dentistry Av. Humaitá 1680 14801–903 Araraquara SP BrazilAndréia Bolzan de Paula, State University of Campinas (UNICAMP) Department of Dental Materials, School of Dentistry of Piracicaba Av. Limeira, 901 13414–903 Piracicaba SP BrazilRita de Cássia Loiola Cordeiro, São Paulo State University (UNESP) Department of Pediatric Dentistry, Araraquara School of Dentistry Av. Humaitá 1680 14801–903 Araraquara SP Brazil
Journal Lasers in Medical ScienceOnline ISSN 1435-604XPrint ISSN 0268-8921 (Source: Lasers in Medical Science)...
POSTED 08/15/2008 at 01:23 AM --
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Severity of oral mucositis in patients undergoing hematopoietic cell transplantation and an oral laser phototherapy protocol: a survey of 30 patients
Photomedicine and Laser Surgery , Vol. 0, No. 0: 1-8.
Abstract Background Data and Objective: Oral mucositis (OM) is one of the worst cytotoxic effects of chemotherapy and radiotherapy in patients undergoing hematopoietic cell transplantation (HCT), and it causes severe morbidity. Laser phototherapy has ... (Source: Photomedicine and Laser Surgery)...
POSTED 08/12/2008 at 10:02 PM --
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Time-resolved resonance raman
study of biphenyl occluded in the
supercages of faujasitic zeolites
The laser photolysis (248 nm, 20 ns) of biphenyl (BP, S0) occluded in the void space of
faujasitic zeolites (NanFAU)
, Nan(SiO2)192−n(AlO2)n
with n=0, 56, 85 has been studied
by time-resolved resonance Raman spectroscopy combined with time-resolved diffuse
reflectance UV-visible absorption spectroscopy in the ns–μs time scale. The excitation
(370 nm, 8 ns) of the RR scattering in the wavelength region of the UV electronic
absorption of the transient species provides clear evidence of the radical cation (BP+) as
major species for zeolites NanFAU (n=56, 85). The amount of triplet state (BP, T1)
depends on the aluminum content and in a less extent on the fluence of the pump laser at
the sample. (Source: Laser Chemistry)...
POSTED 08/12/2008 at 12:25 PM --
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Electronic and vibrational
coherence in photosynthetic
cofactors: comparison
of solutions and proteins
The interaction between photosynthetic cofactors and the surrounding bath or protein
environment is addressed via experimental measurements of the optical coherence
responses from bacteriochlorophylla (Bchla) chromophores within the photosynthetic
reaction center (RC) of Rhodobacter sphaeroides and solutions of Bchla monomers in
THF and pyridine. The results indicate that both the spectrum of fluctuations and
chromophore bath coupling strengths vary between solutions and protein. In particular,
the protein environment yields faster dephasing, faster spectral diffusion, and
significantly more inhomogeneity than solutions. (Source: Laser Chemistry)...
POSTED 08/12/2008 at 12:25 PM --
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Transient absorption spectra of
vibrationally excited water
molecule on zeolite surface
By means of infrared pump-probe technique, spectroscopic feature of vibrationally
excited water molecule (D2O) on mordenite zeolite (OD) has been investigated.
Populational lifetime of the OD stretching band (ν3:2730cm-1) was determined to be
43±5 ps at 123 K by the time evolution of hot band. The transient bleachings and
absorptions appeared when the D2O molecule was promoted to the vibrationally excited
level of the OD stretching modes. Especially, the transient absorption at 2680 cm-1 has
rapid decay time (≈15 ps) and it was assigned as the overtone between ν3 mode and
vibrationally excited ν1 mode (2620 cm-1). (Source: Laser Chemistry)...
POSTED 08/12/2008 at 12:25 PM --
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Transient raman spectroscopy
of isotope-substituted species
of bacteriochlorophyll a,
bacteriopheophytin a and
chlorophyll a: changes in the
bond orders in the macrocycles
upon triplet and singlet
excitation
The S0, T1 and S1 Raman spectra of bacteriochlorophyll a, bacteriopheophytin a and
chlorophyll a were recorded for the species of natural abundance isotopic composition
and those of totally substituted with 15N, 13C and 2H isotopes. Based on empirical
assignments of the Raman lines, changes in the bond orders in the macrocycle upon
triplet and singlet excitation are discussed. (Source: Laser Chemistry)...
POSTED 08/12/2008 at 12:25 PM --
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Enantioenrichments of α -amino acids with high-intensity excimer laser
It has been found that the irradiation with highly intense circularly polarized light (CPL)
from an XeF (351 nm) laser can induce the enantiodifferentiation of racemic methionine
with reasonable enantiocontrol by switching the sense of the CPL. Also, a similar result
was obtained for threonine and it was newly revealed that the enantioenrichment is
largely affected by the chemical structure, especially the functional groups, of α-amino
acids, to cause photodecomposition such as decarboxylation and deamination. Furthermore,
it was shown for the first time that the irradiation of a proline (Pro)-valine
(Val) mixture with the CPL induces their enantioselective decomposition simultaneously,
suggesting the occurrence of intermolecular interaction between Pro and Val. (Source: Laser Chemistry)...
POSTED 08/12/2008 at 12:25 PM --
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Collision-induced e(0g+)−d(0u+) state-to-state energy transfer in i2
Electronic energy transfer in the E(0g+)−D(0u+) system of I2 is investigated in an experiment,
where single rovibrational quantum states are prepared, single collision conditions
prevail, and the final states have been determined from dispersed fluorescence. In
I2∗(E)−X (X=Ar, N2, O2) the collisional decay is found to be governed by minimum
energy transfer. With (X=I2) an anomalous behaviour is found for the initially
prepared E, ν=8, J=56 level, which is tentatively ascribed to vibrational excitation of
the collision partner. (Source: Laser Chemistry)...
POSTED 08/12/2008 at 12:25 PM --
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Analytical studies of polychromes by time-integrated laser-induced
breakdown spectroscopy
Time integrated Laser Induced Breakdown Spectroscopy was applied to the study of real
samples of polychromes. Two samples respectively from the Spanish Baroque and from
the XV century were analysed. The time integrated spectra showed negligible contribution
of continuum background emission. The spectra of the Baroque sample indicated the
presence of vermilion; this was confirmed by Near Infrared Fourier Transform Spectroscopy.
LIBS spectra of the XV century sample showed Ca, Al, Mg, Na and Pb lines and
the molecular emissions CN(B-X) and C2(d-a). Relative spectral intensities were measured
as a function of the number of laser pulses delivered on the same position of the sample.
The LIBS analysis was compared to an exhaustive analytical study. (Source: Laser Chemistry)...
POSTED 08/12/2008 at 12:25 PM --
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Multiphoton ionization and fragmentation of cs2 under intense short pulse laser radiation
The interaction of CS2 with intense short pulse laser radiation is studied, experimentally
using time-of-flight mass spectroscopy. Laser pulses of 0.5 and 5 psec at 248 and 496 nm
have been used in order to investigate the effect of the wavelength and the pulse duration
on the molecular ionization and fragmentation. As shown, for low enough intensities
the parent molecular ion is present as the most important peak in all cases. Increasing
the intensity results in extensive fragmentation, where the molecular parent ion remains
always the more intense mass peak at 496 nm while at 248 nm S+ dominates the mass
spectra. Finally, the production of multiply charged fragments is more efficient at the
longer wavelength used. (Source: Laser Chemistry)...
POSTED 08/12/2008 at 12:25 PM --
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