Application of low-level laser irradiation (LLLI) and rhBMP-2 in critical bone defect of ovariectomized rats: histomorphometric evaluation.

OBJECTIVES: The aim of this study was to evaluate the osteogenic potential of recombinant human bone morphogenetic protein-2 (rhBMP-2) and low-level laser irradiation (LLLI), isolated or combined in critical bone defects (5 mm) in parietal bone using ovariectomized female rats as an experimental animal model. MATERIALS AND METHODS: Forty-nine female Wistar rats, bilaterally ovariectomized (OVX), were divided into seven treatment groups of seven animals each: (I) laser in a single application, (II) 7 µg of pure rhBMP-2, (III) laser and 7 µg of pure rhBMP-2, (IV) 7 µg of rhBMP-2/monoolein gel, (V) laser and 7 µg of rhBMP-2/monoolein gel, (VI) laser and pure monoolein gel, and (VII) critical bone defect controls. The low-level laser source used was a gallium aluminum arsenide semiconductor diode laser device (λ = 780 nm, D = 120 J/cm(2)). RESULTS: Groups II and III presented higher levels of newly formed bone than all other groups with levels of 40.57% and 40.39%, respectively (p < 0.05). The levels of newly formed bone of groups I, IV, V, and VI were similar with levels of 29.67%, 25.75%, 27.75%, and 30.64%, respectively (p > 0.05). The area of new bone formation in group VII was 20.96%, which is significantly lower than groups I, II, III, and VI. CONCLUSIONS: It was concluded that pure rhBMP-2 and a single dose of laser application stimulated new bone formation, but the new bone formation area was significantly increased when only rhBMP-2 was used. Additionally, the laser application in combination with other treatments did not influence the bone formation area.

A terapia fotodinâmica com ácido 5-aminolevulínico como modalidade de tratamento para neoplasias cutâneas não-melanoma / Topical 5-aminolevulinic acid photodynamic therapy as a treatment modality for nonmelanoma skin cancer

FUNDAMENTOS: A terapia fotodinâmica baseia-se na associação de fonte de luz e fotossensibilizador para destruir seletivamente as células. OBJETIVO: Avaliar os efeitos imediatos e tardios, a resposta clínica e os resultados estéticos da terapia fotodinâmica com ácido 5-aminolevulínico em neoplasias cutâneas não-melanoma. MÉTODOS: Trinta e quatro lesões, sendo 19 disceratoses de Bowen e 15 carcinomas basocelulares, foram submetidas à aplicação tópica e oclusiva do ácido 5-aminolevulínico a 20 por cento, por seis horas, e posteriormente a sessão única de laser de diodo (630nm). RESULTADOS: Foram registrados: sensação de queimação durante as sessões; eritema, edema e erosões, nas primeiras 72 horas; cicatrização em média de quatro semanas; resultados estéticos variáveis de excelentes a bons. Aos três meses, a resposta clínica foi de 91,2 por cento, sendo reduzida, aos 18 meses, para 73,3 por cento, de modo similar tanto para disceratose de Bowen (72,2 por cento) quanto para carcinoma basocelular (75 por cento). Foi evidenciada relação de tendência linear entre a redução da freqüência da resposta clínica e o aumento da dimensão das neoplasias cutâneas não-melanoma (p<0,001). CONCLUSÃO: A terapia fotodinâmica com ácido 5-aminolevulínico tópico mostrou destacadas vantagens: minimamente invasiva no tratamento de lesões múltiplas em sessão única ou em sítios de pobre cicatrização com superioridade dos resultados estéticos. O tipo/subtipo(clínico e histopatológico), a dimensão e o adequado seguimento devem ser considerados para a sua indicação no tratamento de neoplasias cutâneas não-melanoma.

BACKGROUND: Photodynamic therapy is based on the association of a light source and photosensitizer in order to selectively destroy cells. OBJECTIVE: To evaluate the short and long-term effects, clinical response, and cosmetic outcome of the photodynamic therapy with 5-aminolaevulinic acid for non-melanoma skin cancer. METHODS: TThirty-four non-melanoma skin cancer - 19 Bowen’s diseases and 15 basal cell carcinomas, were submitted to a single 6-hour topical and occlusive application of 20 percent 5-aminolaevulinic acid, and were later exposed to 630 nm diode laser single session. RESULTS: Burning sensation during the session; erythema, edema and erosions in the first 72 hours; healing process after 4 weeks on average and excellent or good cosmetic results were observed. After 3 months, tumor-free rate was 91.2 percent whereas at 18 months,73.3 percent, similarly in Bowen’s disease (72.2 percent) and basal cell carcinoma (75 percent). It was noticed a linear relation between the reduction in complete clinical response frequency and the increase in tumor dimension (p<0.001). CONCLUSION: The 5-aminolaevulinic acid photodynamic therapy showed significant advantages such as minimally invasive for the treatment of multiple lesions in only one session or lesions in poor healing sites with superior esthetical outcome. The clinical and histopathological type/sub-type, the dimension and an appropriate follow-up must be considered to indicate topical 5-aminolaevulinic acid photodynamic therapy for non-melanoma skin cancer.