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1.
Lasers Med Sci ; 32(5): 1041-1049, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28429193

RESUMO

Phototherapy using coherent light (lasers) and non-coherent light (light-emitting diodes (LEDs)) has been investigated for the purpose of biomodulation in biological tissues. Several effects can be expected, including pain moderation, biostimulation of cellular tropism, anti-inflammatory effects, regular circulatory stimulation, and tissue repair. The aim of this study was to evaluate the effect of LED (λ945 ± 20 nm, 48 mW) therapy on the regeneration process in femoral lesions of rats (Wistar). Seven irradiation sessions were held, with a 48-h interval between sessions. The animals were euthanised 14, 21, and 28 days after surgery. Bone samples were analysed by histomorphometry, micro X-ray fluorescence spectroscopy, scanning electron microscopy, and optical densitometry. The results demonstrated the effective positive influence of low-intensity LED therapy using the near-infrared region on the tissue repair process in diabetic animals, especially in the early stages of repair (14 and 21 days after surgery). It can be concluded that LED therapy positively influences bone formation in the early stages of the bone repair process in non-diabetic and diabetic animals, without causing changes in the optical density and volume of tissue in the final stages. No influence of LED therapy was observed on the percentage of calcium, percentage of phosphorus, Ca/P ratio, or optical mineral density in non-diabetic animals. However, increased mineral concentration was evident in the diabetic animals treated with the LED during the repair process.


Assuntos
Diabetes Mellitus Experimental/patologia , Fêmur/patologia , Fêmur/efeitos da radiação , Raios Infravermelhos , Fototerapia , Espectrometria por Raios X , Cicatrização/efeitos da radiação , Animais , Densitometria , Fêmur/ultraestrutura , Masculino , Ratos Wistar
2.
Photomed Laser Surg ; 33(7): 378-83, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26154726

RESUMO

OBJECTIVE: The purpose of this study was to evaluate surface roughness and changes in the composition of enamel submitted to different bleaching protocols and toothbrushing with regular and whitening toothpastes. BACKGROUND DATA: Bleaching treatment could promote morphological and chemical changes in enamel surface. METHODS: Enamel blocks were randomized into nine groups (n=10) according to the bleaching treatment (no bleaching, control group; 6% hydrogen peroxide, HP; or 10% carbamide peroxide, CP) and toothpaste used (placebo, PL; regular, R; or whitening dentifrice, W). Bleaching was performed according to manufacturers' instructions and all groups were submitted to 30,000 cycles of simulated toothbrushing with toothpaste (PL, R, or W). Mineral content evaluation and enamel roughness were evaluated initially (T1), after bleaching (T2), and after toothbrushing (T3), using an energy-dispersive micro X-ray fluorescence spectrometer and profilometry, respectively. Data were statistically analyzed with two way ANOVA, Tukey, and Dunnett tests (5%). RESULTS: Enamel surface roughness was influenced by bleaching and toothbrushing. Surface roughness increased for the groups that brushed with the placebo dentifrice (CP+PL, HP+PL, C+PL) and for the control group that brushed with whitening dentifrice (C+W). Enamel Ca/P ratio decreased after bleaching, but toothbrushing, regardless of the dentifrice used, did not reduce the enamel mineral content. CONCLUSIONS: The bleaching treatment resulted in a decrease of enamel mineral content, but the studied dentifrices did not contribute to surface mineral loss.


Assuntos
Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/efeitos da radiação , Dentifrícios/farmacologia , Terapia com Luz de Baixa Intensidade , Clareadores Dentários/farmacologia , Clareamento Dental , Humanos , Propriedades de Superfície/efeitos dos fármacos , Propriedades de Superfície/efeitos da radiação , Técnicas de Cultura de Tecidos , Calcificação de Dente/efeitos dos fármacos , Calcificação de Dente/efeitos da radiação , Escovação Dentária
3.
Photomed Laser Surg ; 28(3): 391-6, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19860554

RESUMO

OBJECTIVE: This study aimed to investigate the effects on enamel surface treated with hydrogen peroxide bleaching and acidic soft drink immersion and/or brushing with whitening dentifrices. MATERIALS AND METHODS: Fifty-six standardized enamel slabs obtained from labial surfaces of bovine incisors were used. Enamel slabs were ground flat, polished, and randomly assigned to one of seven treatment groups: (1) control, in which no treatment was performed, (2) soft drink immersion, (3) 38% hydrogen peroxide bleaching, (4) simulated toothbrushing with whitening dentifrice, (5) soft drink immersion and bleaching, (6) soft drink immersion, bleaching, and toothbrushing, and (7) bleaching and toothbrushing. The mineral concentration of enamel surfaces was determined before and after treatments by means of Fourier transform (FT)-Raman spectroscopy and energy dispersive x-ray fluorescence spectrometry (EDXRF). Data were statistically analyzed by ANOVA and Tukey test (p < 0.05). RESULTS: Raman spectroscopy results indicated that enamel mineral content decreased after all treatments except in group 1, whereas EDXRF results exhibited mineral decrease in groups 3, 4, 5, and 7. CONCLUSION: Bleaching alone or in combination with soft drink immersion and brushing decreases enamel mineral content.


Assuntos
Bebidas Gaseificadas , Esmalte Dentário/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Clareamento Dental , Esmalte Dentário/química , Dentifrícios/uso terapêutico , Humanos , Peróxido de Hidrogênio/administração & dosagem , Teste de Materiais , Espectrometria por Raios X , Análise Espectral Raman , Propriedades de Superfície , Clareamento Dental/métodos , Escovação Dentária
4.
Photomed Laser Surg ; 27(5): 771-82, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19878028

RESUMO

OBJECTIVE: The effects of laser-induced compositional changes on the enamel were investigated by energy-dispersive X-ray fluorescence spectrometry (micro-EDX). After cariogenic challenge, we administered treatment of low-level infrared diode laser and a photo-absorbing cream (used to intensify the superficial light absorption). BACKGROUND DATA: Dental caries is considered the most prevalent oral disease. A simple and noninvasive caries preventive regimen is treating tooth enamel with a laser, either alone or in combination with fluoride, which reduces enamel solubility and dissolution rates. High power lasers are still not widely used in private practice. Low-power near-infrared lasers may be an alternative approach. Energy-dispersive micro-EDX is a versatile and nondestructive spectroscopic technique that allows for a qualitative and quantitative elemental analysis of inorganic enamel components, such as calcium and phosphorus. MATERIALS AND METHODS: Twenty-four extracted or exfoliated caries-free deciduous molars were divided into six groups: 1) control group (CTR-no treatment); 2) infrared laser treatment (L) (lambda = 810 nm, 100 mW/cm(2), 90 sec, 4.47 J/cm(2), 9 J); 3) infrared laser irradiation and photo-absorbing agent (CL); 4) photo-absorbing agent alone (C); 5) infrared laser irradiation and fluoridated photo-absorbing agent (FCL); and 6) fluoridated photo-absorbing agent alone (FC). Samples were analyzed using micro-EDX after two sets of treatments and pH cycling cariogenic challenges. RESULTS: The CL group showed statistically significant increases in calcium and phosphorus (wt%) compared with the CTR group. The Ca/P ratio was similar in the FCL and CTR groups. There was a significant laser-induced reduction compared with the CTR group, and there was a possible modification of the organic balance content in enamel treated with laser and cream. CONCLUSION: micro-EDX may be able to detect compositional changes in mineral phases of lased enamel under cariogenic challenge. Our results suggest that with a combined laser and photo-absorbing agent (CL) treatment, there was a possible disorganization of organic content in the tooth enamel with hydroxyapatite crystal reordering and reorganization.


Assuntos
Cárie Dentária/prevenção & controle , Esmalte Dentário/efeitos da radiação , Terapia com Luz de Baixa Intensidade , Cálcio/análise , Esmalte Dentário/química , Humanos , Raios Infravermelhos , Lasers Semicondutores , Fósforo/análise , Espectrometria por Raios X
5.
Photomed Laser Surg ; 27(3): 499-507, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19415988

RESUMO

OBJECTIVE: The aim of this FT-Raman study was to investigate laser-induced compositional changes in enamel after therapy with a low-level infrared diode laser and a photoabsorbing cream, in order to intensify the superficial light absorption before and after cariogenic challenge. BACKGROUND DATA: Dental caries remains the most prevalent disease during childhood and adolescence. Preventive modalities include the use of fluoride, reduction of dietary cariogenic refined carbohydrates, plaque removal and oral hygiene techniques, and antimicrobial prescriptions. A relatively simple and noninvasive caries preventive regimen is treating tooth enamel with laser irradiation, either alone or in combination with topical fluoride treatment, resulting in reduced enamel solubility and dissolution rates. Due to their high cost, high-powered lasers are still not widely employed in private practice in developing countries. Thus, low-power red and near-infrared lasers appear to be an appealing alternative. MATERIALS AND METHODS: Twenty-four extracted or exfoliated caries-free deciduous molars were divided into six groups: control group (no treatment; n = 8); infrared laser treatment (L; n = 8) (810 nm at 100 mW/cm(2) for 90 sec); infrared diode laser irradiation (810 nm at 100 mW/cm(2) for 90 sec) and photoabsorbing cream (IVL; n = 8); photoabsorbing cream alone (IV; n = 8); infrared diode laser irradiation (810 nm at 100 mW/cm(2) for 90 sec) and fluorinated photoabsorbing agent (IVLF; n = 8); and fluorinated photoabsorbing agent alone (IVF; n = 8). Samples were analyzed using FT-Raman spectroscopy before and after pH cycling cariogenic challenge. RESULTS: There was a significant laser-induced reduction and possible modification of the organic matrix content in enamel treated with the low-level diode laser (the L, IVL, and IVFL groups). CONCLUSION: The FT-Raman technique may be suitable for detecting compositional and structural changes occurring in mineral phases and organic phases of lased enamel under cariogenic challenge.


Assuntos
Corantes/farmacologia , Cárie Dentária/prevenção & controle , Esmalte Dentário/efeitos da radiação , Verde de Indocianina/farmacologia , Lasers Semicondutores , Terapia com Luz de Baixa Intensidade , Absorção , Cariostáticos/farmacologia , Intervalos de Confiança , Fluoretos Tópicos/farmacologia , Géis , Humanos , Dente Molar , Pomadas , Fluoreto de Sódio/farmacologia , Análise Espectral Raman , Dente Decíduo
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