Background: Photodynamic therapy (PDT), a minimally invasive cancer treatment involving the activation of photosensitizer by a specific wavelength of light, is considered to be a promising treatment option for drug-resistant prostate cancer. Hemagglutinating virus of Japan envelope (HVJ-E) has the potential to serve as a highly effective cancer therapy through selective drug delivery and enhancement of the anti-tumor immune response.

Objectives: To improve therapeutic efficacy and selective accumulation of photosensitizer into tumor cells, we developed a novel photosensitizer, Laserphyrin^®-HVJ-E (L-HVJ-E), by incorporating talaporfin sodium (Laserphyrin^®, Meiji Seika Pharma) into HVJ-E.

Materials and Methods: The therapeutic effect of PDT with Laserphyrin^® or L-HVJ-E was evaluated in the human prostate cancer cell line PC-3 in vitro. The subcellular localizations of Laserphyrin^® and L-HVJ-E were observed by confocal microscopy. Apoptosis or necrosis following PDT was detected by annexin V–fluorescein/propidium iodide double staining.

Results: The cytotoxic effect of Laserphyrin^®- and L-HVJ-E–mediated PDT were determined by evaluating cell survival rate and production of reactive oxygen species. The cytotoxicity of L-HVJ-E–mediated PDT was dependent on drug concentration and light dose. Laserphyrin^® and L-HVJ-E gradually entered cells as incubation time increased, and both agents tended to be distributed in lysosomes rather than mitochondria. Time and dose dependent increase in ROS production was observed, and induction of both apoptotic and necrotic cell death was confirmed.

Conclusions: Laserphyrin^® and L-HVJ-E were distributed mainly in lysosomes and induced cell death by both apoptosis and necrosis. Furthermore, L-HVJ-E–mediated PDT effectively killed cultured PC-3 cells and exerted higher photocytotoxicity than Laserphyrin^®-mediated PDT.

Background and aims: The present investigation was carried out to determine the levels of blood serum components and inflammatory cytokines in diabetic rat models [Goto-Kakizaki (GK), Zucker, and streptozotocin (STZ)-induced Sprague Dawley (SD) rats] which underwent abdominal Low-Power Laser Irradiation (LPLI) and compare them with non-irradiated controls.

Methods: The animals were subdivided into the following groups: diabetic control rats (GK, Zucker, STZ) and diabetic rats treated with LPLI (GK + LPLI, Zucker + LPLI, and STZ + LPLI) (n = 7). The animals were irradiated three times weekly for 12 weeks in LPLI (830 nm) at a dose of 5 J/cm² for 500 s.

Results: Body weight was significantly lowered in the Zucker- LPLI group compared to control at 10 weeks and this pattern was maintained until 12 weeks of age. TNF-α, IL-1I and IL-6 levels were significantly decreased (5.1 ± 1.1 vs 3.3 ± 0.5, p < 0.01; 43.6 ± 8.8 vs 27.1 ± 3.8, p < 0.01; 98.3 ± 15.8 vs 62.2 ± 12.1, p < 0.01) in the Zucker- LPLI group compared with the control rats. The small intestinal transit rates of charcoal meals were significantly decreased (58.1 ± 10.1 vs 73.4 ± 13.3, p < 0.05) in the Zucker-LPLI

group compared with the control rats. Similarly, the serum levels of glucose, cholesterol and triglycerides of LPLI groups were decreased in comparison with that of diabetic control rats.

Conclusions: We suggest that abdominal LPLI can reduce body weight and LPLI could be applicable for use against diabetic-induced inflammatory factors.

Background and aims: The main purpose of this investigation in Low-Level Laser Therapy (LLLT) on diabetic rats is laser wavelength effect on interleukins: IL-1α, IL-1β, IL6.

Materials (Subjects) and Methods: At first, diabetes was induced in Wistar rats by streptozotocin (STZ) injection. Then, by intravenous laser therapy, the rats were irradiated by four continuous wave lasers: IR (l = 808 nm), Red (l = 638 nm), Green (l = 532 nm) and Blue (l = 450 nm) to compare the related laser wavelength effect on different interleukins. The inflammatory parameters were measured 2,6 and 24 hours after laser therapy from blood samples and plotted for different laser wavelengths.

Results: The results show a decrease in all the above parameters by different laser irradiation in comparison to non-radiated diabetic control ones. More importantly with constant laser energy as the laser wavelength decreases, it affects more efficiently on lowering the above parameters.

Conclusions: we can conclude from our data on diabetic rats that in intravenous LLLT, with constant laser energy, shorter wavelengths like Blue (l = 450 nm) is more effective than longer wavelengths such as Red (l = 638 nm) and IR (l = 808 nm) lasers to lower the level of interleukins toward non-diabetic ones.

Purpose: The aim of this study was to evaluate the combined effect of corticotomy and Low-Level Laser Therapy (LLLT) on the rate of orthodontic tooth movement.

Methods: A randomized split-mouth design for 16 female patients compared the rate of maxillary canine retraction using corticotomy combined with LLLT versus corticotomy only. The device used in the present study was an In-Ga-As semiconductor diode laser emitting at 940 nm (IR) with these parameters: 0.5 W/cm² power density, 5 J/cm² Fluence, CW, 240 sec time irradiation, weekly for the first month and twice monthly for the next three months. Assessment of the rate of canine retraction was carried out via a series of dental models.

Results: A non-significant statistical rate of canine retraction was achieved by LLLT combined to corticotomy compared with the corticotomy technique alone.

Conclusion: Low-Level Laser Therapy combined to corticotomy could not achieve a higher rate of canine retraction compared to the golden standard corticotomy technique alone. No long-term adverse effects on the alveolar mucosa were detected following both techniques.

Background and aims: Penetration of hydrogen peroxide into the pulp chamber and subsequent tooth hypersensitivity is a common concern in dental bleaching. The aim of this study was to assess the penetration of hydrogen peroxide (H₂O₂) into the pulp chamber in diode-laser activated bleaching with different laser wavelengths.

Materials and methods: Fifty extracted human maxillary anterior teeth were collected and divided into five groups (n = 10). Group 1: conventional in-office bleaching using Opalescence Boost gel. Group 2: Bleaching with Biolase Laser White 20 gel activated by 980 nm diode laser. Group 3: Bleaching with Biolase Laser White 20 gel activated by 810 nm diode laser. Group 4: Bleaching with Biolase Laser White 20 gel activated by 940 nm diode laser. Group 5: No bleaching control group.

After bleaching, the solution into the pulp chamber was collected and analyzed using a spectrophotometer. The recorded data were compared with a standard sample and the results were analyzed and compared using one-way ANOVA and Tukey's HSD tests.

Results: In all bleached groups, H₂O₂ had infiltrated into the pulp chamber. The highest level of penetration was noted in group 2 (2.32 ± 0.25 µg), while the lowest level was noted in group 3 (1.85 ± 0.33 µg). The difference in this regard was significant between groups 2 and 3 (P = 0.024), but the differences between other groups were not statistically significant (P ≥ 0.42).

Conclusion: Considering the results of this study, it can be stated that hydroge peroxide penetration in to pulp chamber in diode laser activation of bleaching agent according to manufactures instruction is not higher than in-office bleaching. The wavelength of diode laser had significant effect on penetration of hydrogen peroxide into pulp chamber.

Background: Focal reactive gingival overgrowths (FRGO) are a common observation in a clinical dental practice that may occur in response to external and internal chronic stimuli in form of fibrous connective tissue lesions in the oral mucosa. Gingiva is the most commonly involved site of oral reactive lesions. For the confirmed diagnosis of FRGO not only clinical, but the histopathological presentation of the lesion plays a vital role. Various surgical treatment modalities like a scalpel, cryosurgery, electrosurgery, and lasers have been applied in the management of FRGO. The laser is new treatment modality being employed for treatment of FRGO.

Case report: The purpose of this paper is to attempt short review on FRGO with the management of FRGO using diode laser. Here, we present effective management of peripheral giant cell granuloma and peripheral ossifying fibroma using diode laser. The follow-up of 01year showed no recurrence in both the cases.

Conclusions: Diode soft tissue laser has added advantages like a bloodless surgical field, reduced bacteremia, minimal intra and postoperative discomfort over conventional modalities. Thus it is highly effective in the surgical management of FRGO.