Journal of Lasers in Medical Sciences
Volume:3 Issue: 1, Winter 2012

Laser-assisted vaporization of prostate tissue by means of the KTP laser is in clinical use. Alternative laser sources are available, but are lacking clinical experience. In this study, the capability, feasibility, and post-operative outcome of vaporization of prostate by means of a diode laser were investigated. The light (980 nm, 100 W) of a diode laser was fed into a side-fire fiber introduced through a 22F continuous-flow cystoscope, and thus transmitted to prostate tissue. Normal saline was used for irrigation. The study included 70 males suffering from bladder outlet obstruction due to benign prostatic hyperplasia (BPH) (prostate volume range: 61.1±16.1 cm3). The prostatic lobes were vaporized within the prostatic capsule. Depending on the vaporized tissue, the exposure time was in the range of 60.6±22.6 hours. Post-operative outcome and voiding were evaluated during a follow-up of 24 months. During surgery, no significant blood loss or any fluid absorption occurred. Catheters were removed in the 20.1±4.6 hours. All patients except two were satisfied with their voiding outcome. After removing the catheter, the mean peak urine flow rate significantly increased from 6.8±2.5 ml/s pre-operatively to 15.6±3.1 ml/s post-operatively. No evidence of urgency, dysuria, hematuria, or incontinence was observed. Four patients required re-catheterization andtow of them consecutive TURP. After a 1- month, as well as after a 6-month, a 12-mouth, and a 1-year follow-up, all patients were still satisfied with the outcome. This long term experience showed that 100 W-980 nm-diode-laser vaporization prostatectomy was feasible and appeared to be safe and effective for quickly relieving bladder outlet obstruction due to BPH.

Photonics is a science which research light quantum as the carrier for energy and information. Photonic technology in the meridian and acupoints research has shown the unique advantages, by which the microcosmic material basis and macroscopic phenomena research can be integrated to interpret the occurrence of propagated sensation along meridian and its underling mechanism. This paper focuses on the investigation on light sensing action and heat sensing action along meridian. Firstly, the four aspects of light sensing action were discussed, i.e. light sensing effect along meridian, blocking effect, laser induced effect and underline mechanism of light sensing action along meridian. Secondly, the four items of heat sensing action were discussed as well, i.e. thermo-effects, heat perception ability, laser induced heat effect, underling mechanism on heat sensing effect along meridian. The authors point out that photonic technology, e.g. photonic imaging, and infrared spectrum analysis, biological photons detection and laser Doppler application, can achieve purpose of in vivo, dynamic, multiple comparable study. Thereby the effect of light and heat sensing along meridian can be detected and illustrated by the use of natural science. Light and heat information can be investigated to analyze the relationship between zang-fu organs and meridians, and the functional characteristics of the meridian. Hence, the effect of light and heat sensing along meridian is the break point of the research of photonics in meridian which is beneficial to further study the meridian optics.

Thermal changes in laser assisted root canal therapy with the use of diode laser can predispose tooth structure to the fracture. This study evaluated the changes in flexural strength of dentin blocks after diode laser irradiations (810 nm). A total of 60 dentinal blocks were prepared from freshly extracted teeth in three different thicknesses (300, 500 and 1000 m) and 20 sections in each thickness were divided randomly to the test and control groups. Samples in the test group were irradiated at 2W power setting by scanning movement of 2mm/s of diode laser, and the controls were stored in normal saline. The flexural strength of samples was evaluated by UTM (Universal Tensile Machine). Data analysis was done with the SPSS version 11.5. Samples of 300 had the lowest flexural strength (mean: 71/65 mpa) followed by 500 (116.64 mpa) and 1000 (217.56 mpa). Statistical analysis showed that after laser irradiation, the flextural strength in the samples of 300 was significantly lower than other groups (500, 100)(P= 0.017).Within the limits of this study, diode laser irradiation in laser assisted root canal therapy has no significant effect on flexural strength of root dentinal walls with the thickness of more than 500. Although in areas with critical dentinal width (≤300) this setting can jeopardize root micromechanical properties and predispose tooth to the root fracture.

Corticotomy-facilitated orthodontics provides a means for rapidly moving teeth purportedly with little damaging effects to the periodontium and with greatly reduced treatment time. The aim of this study was to enhance the orthodontic tooth movement by reducing the cortical bone layer (resistant to bone resorption relative to spongious bone) following Er,Cr:YSGG laser irradiation, without reflection of surgical soft tissue flap. In the present experimental study, 8 Male New Zealand rabbits were samples for the research. Right first premolar of each rabbit (experiment group) undergoing treatment for mesial movement with 75 gram of orthodontic force by using closed Ni-Ti coil spring (Dentaurum ®). Coil spring was fixed in cervical region of first premolars by means of ligature wire and No-Mix composite (Dentaurum®) and also, activated to cervical site of Incisors. Left first premolars of subjects were considered as control group. Laser corticotomy was performed in anesthetized rabbits. Samples were sacrificed for determination of tooth movement after initiating premolar protraction on 21th day. The amount of orthodontic tooth movement was assessed by using a metal feeler gauge with the precision or 0.01 mm, between mesial surface of second premolar and distal surface of first premolars. The statistical package of SPSS (Kolmogorov - Smirnov and ANOVA test) was used for analytical evaluation of the measurements. The amount of orthodontic tooth movement in experiment group (mean=1.653±0.34 mm) was significantly (p<0.001) greater than the control group (mean=0.936 ±0.28 mm). The innovated laser assisted corticotomies enhanced the rate of orthodontic tooth movement on the intervention side significantly (p<0.001). The innovated method of laser assisted flapless corticotomy is a useful procedure for reducing treatment time and damage to periodontium. It also eliminates the necessity of more invasive intervention of flap surgery.

Lasers have been introduced as a promising tool in periodontics. Different lasers with various effects are now being used in periodontics. The aim of this article is to overview new horizons that lasers are showing to the periodontics and implants dentistry. The article also points to the drawbacks and limitations of current laser application. There is obviously a great need for further research with stronger designs to make lasers an everyday tool in periodontics.

recurrences and malignant transformation depended on the location, clinical feature, degree of dysplasia and etiological factors. There are different kinds of treatment for this lesion, but using high power laser has some advantages like less pain, swelling, prevention of metastasis, edema, less bleeding (dry surgery) and infection.Case : A 53_year_old man with leukoplakia lesion with moderate dysplasia on the left side of the ventral surface of the tongue was selected for treating with CO2 laser. The average power is set on 6.2 W with frequency of 20 Hz. The irradiation mode was non-contact. The entire lesion evaporated by the laser with 2 mm safety margin. In this case, 80% of lesion was disappeared after 5 weeks and 20% residual was evaporated again with the same parameters in the first time. Less clinical difference was seen between the normal and laser-treated tissue. Using laser in the treatment of oral lesions has many advantages like selective removal of the affected tissues and minimal damage to surrounding tissue leads to excellent wound healing with no or minimal scar and good functional results.

The purpose of this case presentation is to analyze the results of vestibuleplasty around an over-denture based on dental implants to determine the evidence on the effectiveness of laser-assisted surgery root soft tissue management in implant dentistry. The patient in this case report was a 57 year- old male who was completely edentulous, with a mandibular over denture based on 4 standard implants suffering from pain on chewing, and a general discomfort, especially in anterior segment. He received a standard gingival augmentation surgery which failed to create sufficient vestibular depth. A laser-assisted vestibuloplasty was done to make the environment suitable for making a new overdenture. There were statistically significant improvements in vestibular depth and peri implant soft tissue situation by laser. Also, bleeding during surgery was well controlled; the patient’s discomfort and pain were less than the first operation done with gingival graft. Based on our clinical data and review of the literature, it is necessary to develop an evidence-based approach to the use of lasers for the management of soft tissue in oral surgery. Simply, there is insufficient evidence to suggest that any specific wavelength of laser is superior to the traditional modalities of therapy. However, improved hemostasis and patient’s satisfaction can be considered as advantages of adjunctive laser therapy in some clinical situations like vestibuloplasty

It is of utmost importance to make children interested in and willing to use dental services in order to prevent and treat oral diseases. Therefore, pediatric dental practitioners need to learn new technologies such as lasers, in addition to basic principles. Lasers have opened new horizons in the treatment of both soft and hard oral tissue problems in children. The present article describes application of the most commonly used lasers and their advantages and considerations.