Bone neoformation is essential in the osteointegration of implants and has been correlated with the repair capacity of tissues, the blood supply and the function of the cells involved. Laser therapy accelerates the mechanical imbrication of peri-implant tissue by increasing osteoblastic activity and inducing ATP, osteopontin and the expression of sialoproteins. Objective: The aim of the present study was to assess peri-implant bone repair using the tibia of dogs that received dental implants and laser irradiation (AsGaAl 830nm – 40mW, CW, f~0.3mm) through Energy Dispersive X-ray Fluorescence (EDXRF). Methodology: Two groups were established: G1 (Control, n=20; two dental implants were made in the tibia of each animal; 10 animals); G2 (Experimental, n=20, two dental implants were made in the tibia each animal + Laser therapy; 10 animals). G2 was irradiated every 48 hours for two weeks, with a total of seven sessions. The first irradiation was conducted during the surgery, at which time a point in the surgical alveolus was irradiated prior to the placement of the implant and four new spatial positions were created to the North, South, East and West (NSEW) of the implant. The subsequent sessions involved irradiation at these four points and at one infra-implant point (in the direction of the implant apex). Each point received 4J/cm2 and a total dose of 20J/cm2 per session (treatment dose=140J/cm2). The specimens were removed 15 and 30 days after the operation for the EDXRF test. The Mann- Whitney statistical test was used to assess the results. Results: The increase in the calcium concentration in the periimplant region of the irradiated specimens (G2) was statistically significant (p < 0.05), when compared with the control group (G1). Conclusion: The results of the present study show that irradiation with the AsGaAl laser promoted an acceleration in bone repair in the peri-implant region.
Candida albicans plays an important role in triggering infections in HIV+ patients. The indiscriminate
use of antifungals has led to resistance to Candida albicans, which requires new treatment alternatives for
oral candidiasis. Low-level laser therapy promotes a considerable improvement in the healing of wounds
and in curing illnesses caused by microorganisms. The aim of the present study was to assess the effect of
laser radiation on the cell proliferation of Candida albicans in immunosuppressed patients. Six Candida
albicans strains that had been isolated from immunosuppressed patients were divided into a control group
and experimental groups, which received eight sessions of laser therapy (InGaAlP, λ685nm, P = 30mW,
CW, Φ~6 mm and GaAlAs, λ830nm, P = 40mW, CW, Φ~6 mm) using dosimetries of 6J/cm2, 8J/cm2,
10J/cm2 and 12J/cm2 for each wavelength and power. The results were not statistically significant
(Kruskal Wallis, p > 0.05), although the proliferation of Candida albicans was lower in some of the
experimental groups. The dosimetry of 6J/cm2 (GaAlAs, λ830nm, P = 40mW) provided lower mean
scores than the other groups for the growth of Candida. Further studies are required to confirm whetehr
laser therapy is a viable option in the treatment of fungal infections.
The aim of the present study was to histologically assess the effect of laser
therapy (AsGaAl, 830nm, 40mW, CW, φ ~0,6mm, 16J/cm2 per session, four points of 4J/cm2)
on the repair of surgical defects created in the femur of Wistar rats. Background data: Several
techniques have been proposed for the correction of bone defects, including the use of grafts and
membranes. Despite the increase in the use of laser therapy for the biomodulation of bone
repair, very few studies have assessed the associations between laser light and biomaterials.
Method: The defects were filled with synthetic micro granular hydroxyapatite (HA) Gen-phos®
implants and associated with bovine bone membranes (Gen-derm®). Surgical bone defects were
created in 48 rats and divided into four groups: Group IA (control, n=12); Group IB (laser,
n=12); Group IIA (HA + membrane, n=12); Group IIB (HA + membrane + laser, n=12). The
irradiated groups received the first irradiation immediately after surgery. This radiation was then
repeated seven times every 48h. The animals were sacrificed after 15, 21, and 30 days. Results:
When comparing the groups irradiated with implants and membranes, it was found that the
repair of the defects submitted to laser therapy occurred more quickly, starting 15 and 21 days
after surgery. By the 30th day, the level of repair of the defects was similar in the irradiated and
the non-irradiated groups. New bone formation was confirmed inside the cavity by the implant’s
osteoconduction. In the irradiated groups, there was an increment of this new bone formation.
Conclusions: In conclusion, the use of laser therapy, particularly when associated with
hydroxyapatite and biological membranes, produced a positive biomodulation effect on the
healing process of bone defects on the femurs of rats.
The experimental evaluated the photodynamic therapy (PDT) in wound healing. It used 60 male rats, making two circular wounds at each animal. They were treated at 48hs intervals, with methylene blue (MB), low level laser treatment (LLLT) or both, thus resulting in PDT. The wounds were observed 01, 03, 07, 14 and 21 days after and then processed and subjected to HE staining to analyze granulation tissue, necrosis, epithelialization and collagen. After day 1, wounds treated with MB showed necrosis less intense than other groups, and the PDT group showed more intense granulation tissue. At day 3, reepithelialization was absent for half of injuries in the PDT group, and this group was also with lower collagen. However, at day 7, this same group presented reepithelialization more advanced than control group, which did not happen with those treated with MB or LLLT (p = 0.015). The results allow us to conclude that PDT difficulted reepithelization at 7th day and interfered in standard healing. However, when used separately, MB and LLLT interfered significantly compared to the control group, which did not happened to the PDT group. There was no significant difference between the treatment groups in other analysed times.