PURPOSE: To evaluate the effectiveness of a therapeutic laser in the control of postoperative pain, swelling, and trismus associated with the surgical removal of impacted third molars.
PATIENTS AND METHODS: A double-blind, randomized, controlled clinical trial was conducted in 2 groups of 15 patients each undergoing surgical removal of impacted lower third molars under local anesthesia. The experimental group received 4 J/cm(2) of energy density intraorally and extraorally, with a laser with a diode wavelength of 810 nm and output power of 100 mW in a continuous wave. The control group received only standard management. The degree of postoperative pain, swelling, and trismus was registered for both groups.
RESULTS: The experimental group exhibited a lower intensity of postoperative pain, swelling, and trismus than the control group, without significant statistical differences. Patients of both groups required rescue medication; however, the time lapse between the end of the surgery and the administration of the medication was shorter for the control group.
CONCLUSION: The use of therapeutic laser in the postoperative management of patients having surgical removal of impacted third molars, using the protocol of this study, decreases postoperative pain, swelling, and trismus, without statistically significant differences. Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.
OBJECTIVES: To examine the degree of polymerization of nanocomposite resins to test the possibility of using a diode-pumped solid state (DPSS) laser as a light-curing source on behalf of the argon laser.
BACKGROUND: DPSS lasers emitting light at 473 nm have many advantages over argon lasers on account of their compactness, efficiency, and price.
MATERIALS AND METHODS: A 473-nm DPSS laser (LAS) was used with three other light-curing units (a quartz-tungsten-halogen lamp-based unit, a light emitting diode-based unit, and a xenon lamp-based plasma arc unit) to polymerize dental nanocomposite resins. The degree of polymerization was determined by measuring the microhardness, maximum polymerization shrinkage, and increase in temperature during and after light curing. The results were analyzed statistically.
RESULTS: The specimens light cured with LAS showed a microhardness that was similar or superior to the values obtained from the specimens cured with the other light-curing units and maximum polymerization shrinkage values. The maximum increase in temperature by LAS was much lower than that induced by the other light-curing units.
CONCLUSION: LAS effectively polymerizes dental nanocomposite resins to an extent similar to that of recently available light-curing units. The results suggest that LAS has good potential as a light source for light curing of dental nanocomposite resins.
OBJECTIVES: The aim of this study was to evaluate the effectiveness of two types of lasers, the Nd:YAG laser and the 685-nm diode laser, as dentin desensitizers as well as both the immediate and late therapeutic effects on teeth with gingival recession.
MATERIALS AND METHODS: The study was conducted on 56 teeth in 14 patients with Miller's class 1 and 2 gingival recession with clinically elicitable dentin hypersensitivity (DH). The patients were divided into two groups: a Nd:YAG-laser-treated group and a 685-nm diode laser-treated group. DH was assessed by means of an air stimulus, and a visual analog scale (VAS) was used to measure DH. The selected teeth in the two groups received laser therapy for three sessions. Teeth subjected to Nd:YAG-laser treatment were irradiated at 1 W and 10 Hz for 60 sec at 1064 nm, and those receiving 685-nm diode laser treatment were irradiated at 25 mW and 9 Hz for 100 sec.
RESULTS: Significant reductions in DH occurred at all time points measured during the three treatment sessions in both treatment groups. Comparing the means of the responses in the three treatment sessions for the two groups revealed that the Nd:YAG laser group had a higher degree of desensitization compared to the other group (p < 0.01). The immediate and late therapeutic effects of the Nd:YAG laser were more evident than those of the 685-nm diode laser.
CONCLUSIONS: Both of these lasers can be used to reduce DH without adverse effects. Desensitization of teeth with gingival recession with the Nd:YAG laser was more effective than with the diode laser. The Nd:YAG laser appears to be a promising new tool for successfully reducing DH.
OBJECTIVE: To evaluate the ablation capacity of different energies and pulse repetition rates of an erbium-doped yttrium aluminium garnet (Er:YAG) laser on primary dentin by assessing mass loss and to analyze the surface morphology using scanning electron microscopy (SEM).
BACKGROUND DATA: Previous studies have demonstrated the ability of the Er:YAG laser to ablate dentin substrate.
METHODS: Forty-eight sound primary molars were bisected in the mesiodistal direction. The dentin surfaces were flattened, and initial mass (mg) was obtained. A 4-mm2 area was delimited. Specimens were randomly assigned to 12 groups according to the combination of energy (160, 200, 250, and 300 mJ) and pulse repetition rate (2, 3, and 4 Hz). Er:YAG laser irradiation was performed for 20 s. After irradiation, the final mass was obtained, and specimens were prepared for SEM. The data obtained by subtracting the final mass from the initial mass were statistically analyzed using analysis of variance and Tukey test (alpha=0.05).
RESULTS: The pulse repetition rate of 4 Hz provided greater mass loss, and it was different from 2 Hz and 3 HZ. The energy of 300 mJ resulted in greater mass loss, similar to 200 and 160 mJ. SEM micrographs showed dentinal tubule obliteration, structural alterations, and the presence of cracked areas in all specimens.
CONCLUSION: The settings of 160, 200, and 250 mJ at 2 and 3 Hz promoted a good ablation rate with fewer surface alterations in primary dentin.
A wide range of different lasers are used in modern dentistry. The Erbium:YAG laser has a potential of replacing the drill in selected situations; the carbon dioxide laser is a valuable tool in oral surgery; the Argon laser is used in minor surgery and composite curing; the Nd:YAG is used in pocket debridement, tissue retraction and more. This is just to mention a few of the possibilities of the dental laser. The major drawback so far has been the high cost compared to the conventional therapies and the fast development in the field. The high cost of the investment may not have paid off until the next generation of lasers is on the market. So far the majority of the dentists using lasers are mainly the entrepreneurs and the enthusiasts. All the above listed lasers are using, or have the possibility of using high powers, ranging from fractions of a watt to 25 watts or more. Interest from media and patients has been considerable during the last decade, party because of a general interest in "high-tech" and partly because of the eternal dream about an escape from the discomfort experienced in the dental chair. This article will summarize the physics, science and clinic of a quite different type of dental lasers - the low level laser.
Low level lasers
While the lasers already mentioned can be labeled "High level lasers", there is a less known type of lasers called "Low level lasers". These lasers are generally smaller, less expensive and operate in the milliwatt range, 1-500 milliwatts. The therapy performed with such lasers is often called "Low Level Laser Therapy" (LLLT) or just â€œlaser therapyâ€ and the lasers are called "therapeutic lasers". Several other names have been given to these lasers, such as "soft laser" and "low intensity level laser" whereas the therapy has been referred to as "biostimulation" and "biomodulation". The latter term is more appropriate, since the therapy can not only stimulate, but also suppress biological processes [1} Therapeutic lasers generally operate in the visible and the infrared spectrum, 600-900 nm wavelength. However, other wavelengths such as the Nd:YAG at 1064 nm and even the carbon dioxide laser at 10600 nm have been successfully used in laser therapy. The energy used is indicated in Joule (J), which is the number of milliwatts x the number of seconds of irradiation. Thus, 50 mW x 60 seconds produces an energy of 3000 millijoules, equals 3 J. Suitable therapeutic energies range from 1-10 J per point. The dose is expressed in J/cm2. To calculate the dose, the irradiated area must be known. 1 J over an area of 1 cm2 = 1 J/cm2. 1 J over an area of 0.1 cm2 = 10 J/cm2. There is generally no heat sensation or tissue heating involved in this therapy.
The first laser was demonstrated in 1960. It was a ruby laser, 694 nm wavelength. Interest in the medical implications of laser light was high and already in 1967  some of the first reports appeared on the effects of very low doses of ruby light on biological tissues. In animal studies it was observed that experimental wounds healed better if irradiated and that even the shaved fur of the experimental animals reappeared faster in the irradiated areas. There appeared to be a biological window for the dose. If too low, there was no effect, if too high there was a suppressive effect. Not much later the Helium-Neon laser was introduced in research and the results were similar. Later on diode lasers were introduced and they provided the same results, although some wavelengths appeared to be better for certain indications. In particular, the introduction of infrared lasers improved the optical penetration of the light, reaching deeper lying tissues. The first commercially available lasers in the early 80ies were extremely low powered, below 1 mW, in spite of the fact that the first scientific reports used 25 mW. This partly explains the initial controversy about LLLT. With the rapid development of laser diodes, the powers of therapeutic lasers have changed dramatically and diode lasers today are typically in the range of 50-500 mW. Increased power has not only shortened the treatment time but also improved the therapeutic results.
Risks and side effects
The only physical risk in laser therapy is the risk of an eye damage. While never reported to have occurred, the risk of an eye damage must be considered, especially when using an invisible and collimated (parallel) beam. Suitable protective goggles should be worn by the patient for extra oral therapy in the face. Since the therapeutic lasers are well above the ionizing spectrum there is no risk of cancerous changes. Suspected malignancies should of course not be treated by anyone but the specialist. Among the side effects (rarely) observed are:
- temporary increase of pain in chronic pain conditions. It has been suggested that this is a sign of a transfer of the chronic condition into an acute situation.
- tiredness after the treatment. This is probably a result of the pain relief where the pain previously has prevented a normal relaxation pattern
- redness and a feeling of warmness in the area which is irradiated a result of a increases micro circulation
There are more than 2500 scientific studies in the field of laser therapy, among them more than 100 positive double blind studies . In dentistry alone, the number of studies are some 325, from 82 institutions in 37 countries . The quality of these studies vary but it is interesting to note that more than 90% of the studies report on positive effects of lasertherapy. In total, 30 different dental indications have been reported in the literature. The very variety of indications has been used as an argument against the probability of laser therapy. However, it rather shows the input on general biological systems, such as the immunesystem, SOD activity, ATP production, cell membrane permeability, release of transmitter substances etc. Laser therapy science is a complicated matter where a combined knowledge about laser physics, medicine, clinical procedures and scientific rules is essential . Many studies, positive and negative, lack relevant reporting parameters and make a proper evaluation difficult. The existing literature is a sufficient foundation for successful clinical therapy but more research is still needed to find out the optimal parameters. In two recent US meta analyses ,  there was a high overall significance for wound healing, tissue regeneration and pain.
Treatment is often carried out through local irradiation of the site of injury/pain, but it can also be performed on distal points such as regional lymph nodes, ganglia and cervical nerve roots corresponding to the dermatome in question. Pain release can often be achieved in one or two sessions (especially if the reason for the pain still is in a acute stage) whereas many conditions have to be treated during several sessions. When calculating the dosage, parameters such as pigmentation of the skin, condition of the tissue, acute/chronic stage, depth beneath skin/mucosa, transparence of overlying tissue must be considered.
The therapeutic lasers offer improved possibilities in the treatment of pain, wound healing, inflammation and oedema. However, they also offer the dentist a possibility to treat indications previously not within the capability of the general dentist. In the following some examples will be given, each with a selected reference
With the advent of desensitizing agents, the prevalence of treatment-resistant dentinal hypersensitivity has diminished considerably. On the other hand, the placement of composites and inlays has brought a new reason for the very same. Gershman  has shown that dentinal hypersensitivity can be successfully treated with LLLT. Mild pulpitis requires higher doses than the common dentinal hypersensitivity, and repeated treatments. Frequently a sensitive tooth neck can be treated with only one treatment.
Oral herpes (HSV1) is a common feature in the dental operatory. Instead of being a contraindication for dental treatment during the acute period, an onset of HSV1 can be a good reason for a visit to the dentist. As with any treatment of HSV1 a treatment in the early prodromal stage is most successful. The pain will be reduced immediately and the blisters will disappear within a few days. Repeated treatment, whenever a blister appears will lower the incidence of recurrence. Unlike Acyclovir tablets, there are no side effects . It has been shown  that laser therapy can even be used in the latent period between the attacks to lower the incidence of recurrence.
Patients undergoing radiotherapy  and/or chemoradiotherapy  suffer gravely from the mucositis induced by the therapy. Nutrition is troublesome and therapy regimen may have to be suboptimal for this reason. LLLT can be used not only to treat the mucositis but even to reduce it by mucosal irradiation prior to radiotherapy/chemotherapy.
The most frequent complaint among patients is of course pain. LLLT can reduce or eliminate pain of various origins ]6]. Postoperative discomfort after surgery can be substantially reduced by irradiating the operated area postoperatively before the anesthesia wears off.
After oral surgery paresthesias may occur as a result of the surgery, in particular in the mandibular region. LLLT has been used to eliminate or reduce such complications .
While many cases of sinuitis are "dental", a great number of patients arrive in the dental office with sinuitis of a viral or bacterial background. LLLT will in most cases lead to a fast reduction of the symptoms , making the scheduled treatment easier.
Problems in the temporo-mandibular joint region are quite suitable for LLLT. For arthritic cases the treatment is concentrated to the joint area, in myogenic cases the muscular insertions and trigger points are treated. Laser therapy should always be used in combination with conventional treatment but will improve the outcome of the treatment .
It has been shown  that patients suffering from MÃ©niÃ¨re's disease (tinnitus/vertigo) have a significantly increased prevalence of problems in the masticatory, neck and trapezius muscles plus problems in the cervical spine, particularly in the transverse processes of the atlas and the axis. Relaxation of the tension in these muscles plus occlusal stabilisation procedures (occlusal adjustment, bite splint) will reduce or eliminate the symptoms of tinnitus and vertigo in this group of patients. Laser therapy can successfully be used to promote muscular relaxation and pain relief in these cases.
Apart from being extremely debilitating, trigeminal neuralgia can sometimes make dental treatment impossible. While no miracle cure, dentists can offer a great deal of comfort to these patients, and with a non-invasive method .
Zoster in the trigeminal nerve should be treated in its early phase. The zoster attack in itself is bad enough, but not too infrequently a postherpetic neuralgia will persist for years or even lifelasting. Laser therapy is a cost-effective, non-invasive method without side effects .
29 different dental indications are described in the literature, some of them being aphtae, bone regeneration, dentitio dificilis and decubitus.
If a dentist is trained in acupuncture, the low level laser will be a very convenient way of replacing the needles in many instances, for corporal or auricular acupuncture. Needles are not too popular with the patients, so the laser will be appreciated. Even for a dentist not practicing acupuncture, there are some well defined acupuncture points which can be used, for instance to reduce nausea .
The clinical results described above may seem impressive, even to the degree of doubts. However, laser therapy is no panacea and should only be used within the limits of its own merits. Correct diagnosis, proper treatment technique and treatment intervals plus sufficient dosage are all essential to obtain good results.
A large number of in vitro studies have reported on the enhanced killing of bacteria using various dyes in combination with low level lasers. The most frequently used dye has been toluidine blue (TBO) and some of the microorganisms studied are streptococcus mutans (20) and staphylococcus aureus (21). The bactericidal effect of TBO is enhanced by low level laser light and the clinical implications of this combination in cariology and periodontology are indeed promising. Low level laser has also been shown to enhance the release of fluoride from lacquers (22) and resin cements (23).
 Abergel P. et al: Control of connective tissue metabolism by lasers: Recent developments and future prospects. J Am Acad Dermatol. 1984; 11: 1142
 Mester E. et al: Untersuchungen Ã¼ber die hemmende bzw. fÃ¶rdernde Wirkung der Laserstrahlen. Arch Klin Chir. 1968; 322: 1022.
 TunÃ©r J, Hode L. 100 positive double blind studies - enough or too little? Proc. SPIE, Vol 4166, 1999: 226-232.
 TunÃ©r J, Hode L. Low level laser therapy - clinical practice and scientific background. 1999. Prima Books. ISBN 91-630-7616-0.
 TunÃ©r J, Hode L. ItÂ´s all in the parameters: a critical analysis of some well-known negative studies on low-level laser therapy. Journal of Clinical Laser Medicine & Surgery. 1998; 16 (5): 245-248.
 Parker J et al. The effects of laser therapy on tissue repair and pain control: a meta-analysis of the literature. Proc. Third Congress World Assn for Laser Therapy, Athens, Greece, May 10-13 2000; p. 77.
 Bouneko J M et al. The efficacy of laser therapy in the treatment of wounds: a meta-analysis of the literature. Proc. Third Congress World Assn for Laser Therapy, Athens, Greece, May 10-13 2000; p 79.
 Gerschman J A et al. Low Level Laser in dentine hypersensitivity. Australian Dent J. 1994; 39: 6.
 VÃ©lez-Gonzalez M et al. Treatment of relapse in herpes simplex on labial and facial areas and of primary herpes simplex on genital areas and â€œarea pudendaâ€ with low power HeNe-laser or Acyclovir administred orally. SPIE Proc. 1995; Vol. 2630: 43-50
 Schindl A, Neuman R. Low-intensity laser therapy is an effective treatment for recurrent herpes simplex infection. Results from a randomized double-blind placebo-controlled study. J Invest Dermatol. 1999: 113 (2): 221-223.
 Bensadoun R J, Franqiun J C, Ciais C et al. Low energy He/Ne laser in the prevention of radiation-induced mucositis: A multicenter phase III randomized study in patients with head and neck cancer. Support Care Cancer. 1999; 7 (4): 244-252.
 Cowen D et al. Low energy helium neon laser in the prevention of oral mucositis in patients undergoing bone marrow transplant: results of a double blind randomized trial. Int J Radiat Oncol Biol Phys. 1997; 38 (4): 697-703.
 Khullar S M et al. Effect of low-level laser treatment on neurosensory deficits subsequent to sagittal split ramus osteotomy. Oral Surgery Oral Medicine Oral Pathology. 1996; 82 (2): 132-8.
 Kaiser C et al. Estudio en doble ciego randomizado sobre la eficacia del HeNe en el tratamiento de la sinuitis maxilar aguda: en pacientes con exacerbaciÃ³n de una infecciÃ³n sinusal crÃ³nica. [Double blind randomized study on the effect of HeNe in the treatment of acute maxillary sinuitis: in patients with exacerbation of a chronic maxillary sinuitis]. BoletÃn CDL. 1986; 9: 15. Also in Av Odontoestomatol. 1987; 3 (2): 73-76.
 Sattayut S. PhD dissertation, St. Bartholomew's and the Royal London School of Medicine and Dentistry. 1999.
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 Eckerdal A, Lehmann Bastian H. Can low reactive-level laser therapy be used in the treatment of neurogenic facial pain? A double-blind, placebo controlled investigation of patients with trigeminal neuralgia. Laser Therapy. 1996; 8: 247-252.
 Moore K et al. LLLT treatment of post herpetic neuralgia. Laser Therapy. 1988; 1: 7
 Schlager A et al. Laser stimulation of acupuncture point P6 reduces postoperative vomiting in children undergoing strabismus surgery. Br J Anesth. 1998; 81 (4): 529-532.
 Burns T, Wilson M, Pearson G. Effect on dentine and collagen on the lethal photosensitization of streptococcus mutans. Caries Res. 1995; 29: 192-197.
 Wilson M, Yianni C. Killing of methicillin-resistant staphylococcus aureus by low-power laser light. J Med Microbiol. 1995; 42: 62-66. Kazmina S et al. Laser prophylaxis and treatment of primary caries. SPIE Proc. 1984; 1994: 231-233.
 van Rensburg S D, Wiltshire W A. The effect of soft laser irradiation on fluoride release of two fluoride-containing orthodontic bonding materials. J Dent Assoc S Afr. 1994; 49 (3): 127-31
In recent years there has been increasing number of dentists using laser technology, either low or highenergy level lasers. There is no laser yet developed that totally replaces the conventional rotary instruments, but some routine work in dental practice can now be done with use of lasers This lecture will give a brief overview of dental disorders, where LLLT proved to be an efficient therapeutic procedure, whether applied as monotherapy or complementary treatment modality LLLT is mainly used for the treatment of soft tissues inside oral cavity, in orde to relieve the pain or to induce wound healing, or as a diagnostic device for dental diseases like early detection of caries. Effects of LLLT are based upon biostimulative-regenerative effect, anti-inflammatory and analgesic effect
Here are some of pathological changes, which can successfully be treated with LLLT:
- Wounds after extractions
- Recovery after dental and periodontal surgical procedures
- Open and closed wound healing after minor and major oral surgery
- Lip wounds and combustions
- Scar tissue
- Alveolitis sicca
- Herpes labialis
- Dentitio difficilis
- Damages of the mucosa due to the incorrectly sitting prosthesis
- Crown preparation
- Nerve lesions
- Acute and chronic disease of periodontal tissue
- Neuralgia n. trigemini
-mandibular joint disorders
This lecture will bring you exact irradiation techniques and efficient energy densities, which are determined after many years spent in the clinical application of LLLT in dentistry.
The possibility of reducing the patients' pain and anxiety through low level laser applications has been the main objective of my research within laser therapy. This Editorial deals with the low level laser as an indispensable and irreplaceable tool for the dentist nowadays in the dental office, focusing on an innovative operator modality: its preventive performance.
*** Clinically, the use of low level laser therapy has demonstrated excellent results. In terms of tissue healing, largely discussed, it shows evidence of the acceleration process in up to three times, mainly for those patients with physiological disturbances,. This may be considered as an indispensable and preventive procedure. Furthermore, the patient's temporary dysfunction, provoked by a wound, being surgically or not, is reduced. This fact causes a comfort that can be achieved only by low level laser. My double-blinded study compared a group without laser and with systemic analgesic medication with two other groups with laser: one group with laser only after the surgical procedure and the other with laser therapy before and after the surgery. This study clarified that 790 nm laser therapy with a dose of 1,5 J/cm2 was as effective with regards to the analgesic and anti-inflammatory effect as conventional medication, both for the pain and oedema control.
To accomplish the present study, 45 clinical situations were selected during the Graduation Course of in Implant and Prosthesis of 3i Implants Innovations, Inc., in RibeirÃ£o Preto, SÃ£o Paulo, Brazil. The selection approach was just constituted in writing in the consent on the part of the patient taking the responsibility in coming back for the follow up care, and also in executing the rules imposed by the methodology of the research. To all the patients it was instituted a systemic medication of preventive antibioticotherapy was instituted and also continued after the surgical procedure for 6 days to the base of penicillin, and for the allergic ones, to the clindamicin base. The piece of equipment of low powered laser chosen was a semiconductor diode of GaAlAs (galium, aluminum and arsenium), that emits in the infra-red close with wavelength of 790 nm and pick power of 30 mW. The emission type is continuous and the application form should be accomplished contacting the gingival tissue; the area of the active point of the crystal of quartz is of 0.13 cm2 (Compact Laser, J. Morita Co., Japan).
The patients were divided in three different groups, constituted of 15 clinical situations each one, as follows:
Â· Group I: Control, the laser application was simulated, without working the "start", just leaving a "bip" ring. All the patients from that group received that simulation during one minute scanning the operated area. Those patient were well informed with the analgesic and anti-inflammatory systemic medication to the piroxican base (Cicladol 20 mg) twice a day in the postoperative for a period of three days.
Â· Group II: Lasertherapy sessions in the postoperative immediate, of 24 hs and of 48 hs. It was not instituted the analgesic and anti-inflammatory systemic medication.
Â· Group III: Lasertherapy sessions in the pre-operative of -48 hs, -24 hs and minutes before the surgical intervention and also in the postoperative in the same way that in the Group II. The patients were equally well educated and have not taken the analgesic and anti-inflammatory systemic medication.
The Group III was elaborated based in NICCOLI FILHO's studies (1995) that used the low power of density laser radiation with prevention. All the applications were accomplished using the same energy parameters and for the same operator and the way of the application was accomplished sweeping the whole area of the tissue to be irradiated, which should be dry preferentially to allow the minimum reflection of the light for the energy not to be lost and absorbed by the tissue. The point of the equipment that contacted the tissue was involved with plastic by hygiene measure and of infection control (in the same way as it is made clinically) which promotes the loss of 10% of energy, that however is not important. The time of each application was calculated in agreement with the formula of density power ( or intensity). The area of each clinical situation had been calculated associating the clinical exam to the radiographic, determining the same for the probable operative field that would be explored. The chosen energy was based on the studies of Kubasova that says the energy of 0.5 to 5.0 J/cm2 is enough for obtaining of the analgesia effects and of bioestimulation effects. Being like this, the chosen energy density was of 1.5 J/cm2.
The measures, with relationship to the pain and the edema, were accomplished in the immediate postoperative and in the postoperative of 72 hours, always for the same examiner. The examiner asked the patient previously to the laser application what the pain degree was in that moment considering the values of the table 1. with relationship to the edema analysis, the examiner checked the value to each case, according to the table 2. When we irradiated the area to be operated, like suggested by Niccoli Filho (1995), we believed that we were "preparing" the cells, mainly for the chemical mediators liberation, especially for the histamine, which acts by increasing the vascular permeability.
According to Ovsiannikov, this procedure stimulates the immune system. Mikailov and Denisov compared three groups of 112 patients with stages IV of stomach cancer; 32 patients received LLLT before surgery, 38 received it after surgery, and 29 patients did not receive LLLT at all. The laser therapy before the operation was slightly more effective. LLLT increased T-active rosette cells and T-helpers, and decreased Tsuppressor cells. The life span of the LLLT patients, as compared to the control group increased by a factor of 2 if surgery was performed and by a factor of 3 if surgery was not performed.
The statistical analysis was just accomplished to check the clearly observed clinical discoveries scientifically. The non-parametric Test of Wilcoxon which compares equal of samples, and with significance degree at level of 5.0% (Tab. 3) was chosen. With relationship to the painful sensitivity, when we compared GI with GII, and GI with GIII, so much in the immediate postoperative as in the postoperative of 72 hours, we observed there were not significant statistical differences. Even so, in the immediate postoperative, GIII shows a tendency in being significant, suggesting a superior behavior to GII. With relationship to the edematous formation, we compared GI with GIII, so much in the immediate postoperative as in the postoperative of 72 hours, we didn't observe significant statistical difference; differently to what we compared, in that situation, GI with GII, where a great tendency to the significance happens.
Table 3 - Statistical results with significance degree at level of 5.0%, when Tc = 138
Event Samples Pairs Immediate PO PO of 72 hours
Pain GI - GII
GI - GIII
| 45.5 |
| 107.5 |
| 67.5 |
| 22.5 |
Edema GI - GII
GI - GIII
| 133.5 |
| 42.0 |
| 135.0 |
| 90.0 |
In agreement with the applied methodology and with the obtained results, the use of low power density laser in implanted patients suggested:
1 - A similar behavior to the analgesic and anti-inflammatory systemic medication, suggesting the possibility of replacement;
2 - for pain control, lasertherapy sessions in the pre-operative were more effective than the postoperative lasertherapy sessions, as executed in GIII;
3 - for tumor formation control, lasertherapy sessions in the postoperative were enough, as executed in GII. Cells with acid pH are more susceptible to light. Furthermore, the possible mechanism at a cellular level probably is depending on the monochromatic carachter of the light, which the organisms are not adapted to evolutionwise. Thus, laser light is one of the environment factors (external agents) capable of modifying the cellular proliferation. The stimulus or inhibition caused by the light may be regarded as a sensorial answer to accommodate to the environmental conditions.
So the question is: why don't we prepare the target tissue through low level laser irradiation as a preventive procedure prior to the trauma?
1. KARU, T. I. Photobiological fundamentals of low-power laser therapy". Journal of Quantum Eletronics, v. QE-23, 10, October, 1987.
2. KARU, T. I. Molecular mechanism of the therapeutic effect of low-intensity laser radiation. Lasers in the Life Sciences; 2(1): 53-74, 1988.
3. LIZARELLI, R. F. Z.; LAMANO-CARVALHO, T. L.; BRENTEGANI, L. G. Histometrical evaluation of the healing of the dental alveolus in rats after irradiation with a low-powered GaAlAs laser. In: Lasers in Dentistry V, John D. B. Featherstone, Peter Rechmann, D.D.S., Daniel Fried, Editors, Proc SPIE Vol. 3593, p. 49-56, 1999.
4. LIZARELLI, R. F. Z.; CICONELLI, K. P. C.; BRAGA, C. A.; BERRO, R. J. Low-powered laser therapy associated to oral Implantology. in Lasers in Dentistry V, John D. B. Featherstone, Peter Rechmann, D.D.S., Daniel Fried, Editors, Proc SPIE Vol. 3593, p. 69-73, 1999.
5. NAVRATIL, L.; DYLEVSKY, I. Mechanisms of the analgesic effect of therapeutic lasers in vivo. Laser Therapy, 9: 33-40, 1997.
6. NICCOLI FILHO, W. D. EficÃ¡cia da radiaÃ§Ã£o de dois diferentes tipos de laser de baixa energia (HeNe e GaAlAs) na prevenÃ§Ã£o de mucosites orais em pacientes submetidos a transplantes de medula Ã³ssea. Tese de Livre DocÃ©ncia. SÃ£o JosÃ© dos Campos: Faculdade de Odontologia de SÃ£o JosÃ© dos Campos UNESP, 1995. 68p.
7. OVSIANNIKOV, V. A. Analysis of the low-energy laser treatment of some cancers and infections diseases. Journal of Clinical Laser Medicine and Surgery, 15(1):39-44, 1997.
8. MIKHAILOV, V. A., DENISOV, I. N. Activation of the immune system by low level laser therapy (LLLT) for treating patients with stomach cancer in advanced form. Laser and Technology;7,(1): 31-44, 1997. Arch Immunol Ther Exp (Warsz). 2005 Sep-Oct;53(5):388-98.
Orthodontic forces are known to produce mechanical damage and inflammatory reactions in the periodontium and dental pulp, as well as inflammatory mediators, e.g. prostaglandins, interleukin (IL)-1, IL-6, tumor necrosis factor alpha, and receptor activator of nuclear factor kappaB ligand, in the periodontal ligament (PDL) and dental pulp. We have studied the effects of aging on the production of inflammatory mediators in the PDL using in vitro and in vitro methods and found that aging of PDL tissues may be an important factor in the severity of periodontal disease through a higher production of inflammatory mediators in response to mechanical forces. Further, the levels of inflammatory mediators in gingival crevicular fluid, an osmotically mediated inflammatory exudates found in the gingival sulcus, have been shown to be significantly elevated during orthodontic treatment. In order to reduce inflammation, low-level laser therapy has been recently studied in vitro and in vitro by many investigators as a substitute for anti-inflammatory drugs. Clinical and experimental studies have shown that low-level laser irradiation reduces orthodontic post-adjustment inflammation. We believe that orthodontic forces (mechanical forces) may play an important role in periodontal inflammation and that low-level laser therapy may be useful for its inhibition
The use of laser therapy as the agent reinforcing conventional treatment of the periodontal diseases becomes more and more common. In the physiotherapy of the periodontal diseases the biostimulating, laser is eagerly used because of its action which accelerates the healing of wounds and also because of its antioedematous, anti-inflammatory and analgesic action. The aim of work was the evaluation of the influence of laser biostimulation on the change of the periodontological pockets depth after the routine conservative periodontological treatment with additional use of laser biostimulation and without it for two groups of pockets: above and below 5 mm. In six patients having periodontitis 613 sites were submitted to the statistic analysis (290 treated conservatively only, including 251 with the depth 2-5 mm and 39 above 5 mm as well as 323 with the use of laser therapy including 297 shallow pockets and 26 deep ones). The initial values of API, SBI, PPD and their changes in the course of the treatment were registered. During each control appointment the patients subjectively estimated periodontal pain occurrence. In both studied groups statistically essential decrease of the evaluated parameters was obtained. Reinforcing the conventional treatment with laser biostimulation shortens its duration and leads to the elimination of pain faster than with the use of conservative treatment only. The changes of the PPD index among the successive examinations were statistically essentially higher in the therapy with the use of laser, especially in relation to deep pockets.
The aim of this study was to evaluate in vivo the use of low-level galium-aluminium-arsenide (GaAlAs) (BDP 600) laser and sodium fluoride varnish (Duraphat) in the treatment of cervical dentine hypersensitivity. Twelve patients, with at least two sensitive teeth were selected. A total of 60 teeth were included in the trial. Prior to desensitizing treatment, dentine hypersensitivity was assessed by a thermal stimulus and patients' response to the examination was considered to be a control. The GaAlAs laser (15 mW, 4 J/cm2) was irradiated on contact mode and fluoride varnish was applied at cervical region. The efficiency of the treatments was assessed at three examination periods: immediately after first application, 15 and 30 days after the first application. The degree of sensitivity was determined following predefined criteria. Data were submitted to analysis and no statistically significant difference was observed between fluoride varnish and laser. Considering the treatments separately, there was no significant difference for the fluoride varnish at the three examination periods, and for laser therapy, significant difference (P < 0.05) was found solely between the values obtained before the treatment and 30 days after the first application. It may be concluded that both treatments may be effective in decreasing cervical dentinal hypersensitivity. Moreover, the low-level GaAlAs laser showed improved results for treating teeth with higher degree of sensitivity.
A total of 103 patients with exacerbation of chronic generalized periodontitis of moderate and high severity were treated using running alternating magnetic field generated by ATOS device and transcutaneous laser biostimulation of the blood. These treatment modalities accelerated preoperative treatment and allowed performing the operations on the periodontal tissues in the optimal status under conditions of improved defense forces of the organism.
Clinical research 242 patients for comparison purposes of efficiently of employment of semiconductor laser apparatus "Uzor" and "Optodan" as physiotherapeutic of the factor for preventive maintenance and treatment of complications, arising the ambassador endodontic of treatment is spent. Results of application of semi-conductor laser apparatus are resulted at the various forms pulpitis and periodontitis. Significant reduction of a pain directly after a procedure LSL is marked. The highest efficiency is established by use of the apparatus "Optodan", connected with distinction configurations of a impulse.