Laser photobiomodulation effect on fibroblasts viability exposed to endodontic medications

Aim: The literature has not yet reported investigations about the effect of laser photobiomodulation (LPBM) over the cytotoxicity of drugs for endodontic treatments. Thus, the aim of this study was to evaluate, in vitro, the effect of the association between LPBM and intracanal medications on fibroblasts viability in different exposure times. Methods: Calcium hydroxide (Ca(OH)2) and iodoform (IO) were used pure or associated to LPBM. Eluates of medications were prepared and placed in contact with the cells in three different periods: 24h, 48h and 72h. Laser irradiation (emitting radiation λ 660nm, power density of 10mW, energy density of 3 J/cm²) has been performed in two sessions within a six hour interval, for 12s per well. After each experimental time, the colorimetric assay (MTT) has been performed. Statistical analysis was applied for Mann-Whitney test with 5% α error admitted test. Results: At 24h, the use of LPBM did not increase cell viability while after 72h cell proliferation was stimulated in the group without medications. LPBM application did not increase cell viability in Ca(OH)2 group and IO at any tested time. Ca(OH)2 cytotoxicity at 24h was higher than iodoform, while at 72h not difference was observed. Therefore, after 72 hours was no statistical difference between the IO and Ca(OH)2 groups. Conclusion: LPBM was able to increase cell viability in 72h in the group without medication, although no improvement was observed in the other groups. Thus, LPBM was not able to reduce the cytotoxic effects of the materials on fibroblasts in vitro

Accuracy of the dental pulp sensibility test using cold spray for the diagnosis of pulp diseases: an observational clinical study

The dental pulp sensibility test is one of the main auxiliary resources for the diagnosis of pulp pathologies, and its accuracy is still debatable. This cross-sectional observational study evaluated the accuracy of the pulp sensibility test (PST) using cold spray (1,1,1,2-tetrafluoroethane) for the diagnosis of pulp diseases and determined the effect of individual and clinical variables on the reliability of this test. The paper was designed following the STROBE statement. Sixty patients with indications for primary endodontic treatment were selected and examined from August 2017 to July 2018. Data collection was performed through interviews, clinical/radiographic examinations and the PST. The results of the cold test, along with data on sex, age, the tooth type regarding the root number, and the presence of restorations and caries, as well as the recent consumption of analgesics, were recorded. The presence of bleeding within the pulp chamber was used as the gold standard to compare with the clinical diagnosis and to identify the true-positive, false-positive, true-negative, and false-negative responses. The accuracy of PST achieved in subgroups of individual and clinical variables was compared using the chi-square test with a significance level of 5% (p < 0.05). The PST with the use of cold spray showed a sensitivity of 0.88, a specificity of 1.00, a positive predictive value of 1.00, a negative predictive value of 0.86, and an accuracy of 0.93. The accuracy of the cold spray was not affected by individual or clinical variables. The PST with the use of cold spray is an accurate and reliable method for determining the diagnosis of pulp diseases, especially in cases of pulp vitality or irreversible pulpitis.

Assessment of carvacrol paste as endodontic medication associated with laser photobiomodulation in tissue repair: an experimental study in rats / Avaliação da pasta de carvacrol como medicação endodôntica associada à fotobiomodulação a laser no reparo: um estudo experimental em ratos

This study aimed to analyze the tissue reaction caused by carvacrol paste associated or not with laser photobiomodulation (LPBM) at λ660 nm in the subcutaneous tissue of rats. Sixty Wistar rats were divided into four groups and they received the following interventions: subcutaneous implantation of empty polyethylene tubes (CTR), implantation of tubes containing carvacrol paste (CVC), implantation of empty tubes and LPBM (LLLT), and implantation of tubes containing carvacrol paste and LPBM (CVCLT). The animals were euthanized at three, eight, and 15 days after surgery. The inflammatory reaction and fibroplasia were analyzed histomorphometrically. Significant differences among the groups were determined by ANOVA and Tukey's test (p<0.05). In the 3-day period, the CVCLT group had low inflammatory infiltration (p<0.01). In the 8- and 15-day periods, the LLLT and CVCLT groups presented a low amount of lymphocytic inflammatory infiltrate (p<0.01 and p<0.05). Regarding the formation of fibrous tissue, the CVC group had the highest formation of type III collagen in the 8-day period (p<0.001). In the 15-day period, the CVCLT group had a lower formation of type I collagen than the CTR and LLLT groups (p<0.05). The use of the carvacrol paste associated with photobiomodulation optimizes the inflammatory period and tissue repair.

Este estudo teve como objetivo analisar a reação tecidual causada pela pasta de carvacrol associada ou não à fotobiomodulação a laser (LPBM) a λ660 nm no tecido subcutâneo de ratos. Sessenta ratos Wistar foram divididos em quatro grupos e receberam as seguintes intervenções: implantação subcutânea de tubos de polietileno vazios (CTR); implantação de tubos contendo pasta de carvacrol (CVC); implantação de tubos vazios e LPBM (LLLT); implantação de tubos contendo pasta de carvacrol e LPBM (CVCLT). Os animais foram eutanasiados aos 03, 08 e 15 dias após a cirurgia. A reação inflamatória e a fibroplasia foram analisadas histologicamente. Diferenças significativas entre os grupos foram determinadas pelo teste ANOVA e teste de Tukey (p<0,05). No período de três dias, o grupo CVCLT apresentou menor infiltração inflamatória (p<0,01). No período de 8 e 15 dias, os grupos LLLT e CVCLT apresentaram menor quantidade de infiltrado inflamatório linfocitário (p<0,01 e p<0,05). Em relação à formação de tecido fibroso, o grupo CVC apresentou maior formação de colágeno tipo III no período de 8 dias (p<0,001). No período de 15 dias, o grupo CVCLT apresentou menor formação de colágeno tipo I em relação aos grupos CTR e LLLT (p<0,05). O uso da pasta de carvacrol associado à fotobiomodulação a laser otimiza o período inflamatório e o reparo tecidual.

Effects of different protocols of low-level laser therapy on collagen deposition in wound healing

Abstract The low-level laser has proven successful in stimulating the production of collagen in wound healing assays. However, diversity has been observed in the protocols used. This work has evaluated the effects of three protocols of low-level laser therapy (LLLT) in the healing of open wounds in rats. Standard-sized wounds of 1 cm2 were performed with a scalpel in the middorsal region of 60 male Wistar rats weighing 225±25 g, and they were assigned into four groups (n=15): CTR (non-irradiated animals), LT1 (20 J/cm2 daily), LT2 (16 J/cm2 daily) and LT3 (20 J/cm2 daily). After 7, 14 and 21 days, five animals/day were euthanized and the wounds analyzed histologically. Data were subjected to normality analysis of distribution using Shapiro-Wilk test. Gaussian data were analyzed using ANOVA and Bonferroni tests whereas non-Gaussian data were analyzed using Kruskal-Wallis and Dunn tests, considering significant p values less than 0.05. The LLLT in all protocols reduced the inflammation and collagen deposition increased significantly (p<0.05). However, LT2 showed the highest levels of collagen in all phases of the study (p<0.05) induced faster replacement of immature collagen III by mature collagen I in the early stages of repair and early collagen remodeling promoted by providing better organization architectural beams deposited. It was concluded that all protocols induced an increase in collagen scar. However, the protocol 2 (16 J /cm2, daily application) promoted the most significant increases in collagen deposition, accelerated maturation of collagen and showed the best architecture of the final fibrous scarring.

Resumo O laser de baixa potência provou ter sucesso em estimular a produção de colágeno em ensaios de cicatrização de feridas. Entretanto, grande diversidade tem sido observada nos protocolos utilizados. Este trabalho avaliou os efeitos de três protocolos de Terapia a Laser de Baixa Potência (TLBP) na cicatrização de feridas abertas em ratos. Feridas padronizadas com 1 cm2 de tamanho foram realizadas com um bisturi na região do dorso de 60 ratos Wistar machos pesando 225±25g, e foram divididos em quatro grupos (n=15): CTR (animais não irradiados), LT1 (20 J/cm2 diariamente), LT2 (16 J/cm2 diariamente) e LT3 (20 J/cm2 diariamente). Após 7, 14 e 21 dias, cinco animais/dia foram eutanasiados e as feridas analisadas histologicamente. Os dados foram submetidos à análise de normalidade da distribuição pelo teste de Shapiro-Wilk. Os dados gaussianos foram analisados pelos testes ANOVA e Bonferroni, enquanto que os dados não Gaussianos foram analisados pelos testes de Kruskal-Wallis e Dunn, considerando-se valores p significativos menores que 0,05. A TLBP em todos os protocolos reduziu a inflamação e aumentou significativamente a deposição de colágeno (p<0,05). Entretanto, LT2 apresentou os maiores níveis de colágeno em todas as fases do estudo (p<0,05), induzindo a substituição mais rápida do colágeno imaturo III pelo colágeno maduro I nos estágios iniciais de reparo e remodelação precoce do colágeno promovida por melhor organização dos feixes depositados. Concluiu-se que todos os protocolos induziram aumento da cicatriz de colágeno. Entretanto, o protocolo 2 (16 J/cm2, aplicação diária) promoveu os aumentos mais significativos na deposição de colágeno, acelerou a maturação do colágeno e apresentou a melhor arquitetura da cicatriz fibrosa final.

Epidemiological Aspects of Cranioencephalic Trauma at Cuiabá Municipal Hospital, Brazil / Aspectos Epidemiológicos de los Traumatismos Craneoencefálicos Atendidos en el Hospital Municipal de Cuiabá, Brasil

ABSTRACT: Cranioencephalic trauma (CET) is defined is the combination of neural and vascular injuries and their inflammatory effects in the brain, skull and scalp. This modality of trauma may lead to motor, psychological and cognitive sequels or even death. The present study aimed to assess the main epidemiological aspects in victims of CET treated at Cuiabá Municipal Hospital (CMH), Brazil. An observational and analytical study was performed in the medical records of patients diagnosed with CET treated at CMH between July and December of 2000, 2006 and 2011. The information retrieved from the patients consisted of age, sex, place of residence, cause of trauma, association with other trauma, outcomes (death or discharge) and the severity of neurological effect (Glasgow Coma Scale). The data obtained was analyzed descriptively with absolute (n) and relative (%) quantification. Medical records of 669 victims were analyzed, out of which 567 were males (84.7 %). Male patients were aged between 20 and 39 years old (mean age: 32.8 years). The most prevalent cause of trauma was the motorcycle accident (26.6 %). The neurological severity of the CET was mild in most of the cases (32.5 %). Considering the place of residence, most of the patients (n=331; 49.5 %) were from the capital city of Mato Grosso State (Cuiabá, Brazil). Four-hundred seventy-nine (71.6 %) patients progressed without death. A high prevalence rate of CET was observed at CMH. Major attention must be given to young adult victims of motorcycle accidents.

RESUMEN: El traumatismo craneoencefálico (TCE) se define como una combinación de daño neural, insuficiencia vascular y efectos inflamatorios que comprometen el cráneo, el encéfalo y el cuero cabelludo, causando la muerte, o serias secuelas motoras, psicológicas y cognitivas. De esta forma, el objetivo de este trabajo fue evaluar los principales aspectos epidemiológicos en victimas de Traumatismo Craneoencefálico (TCE) atendidas en el Hospital y Sala de Primeros Auxilios Municipal de Cuiabá (HPSMC), Brasil. Se trata de un estudio observacional de historias clínicas del archivo del HPSMC, admitidos con diagnóstico de TCE en el período de julio a diciembre de los años 2000, 2006 y 2011. Se consideraron el rango de edad, el sexo, la procedencia de las víctimas, la causa del trauma, la asociación con otros traumas, la defunción y el alta, el cuadro neurológico (Escala de Coma de Glasgow - ECG). El análisis de los datos fue descriptivo con números absolutos y porcentajes. Se evaluaron historias clínicas de 669 víctimas de TCE, en los que el sexo masculino fue el de mayor prevalencia con 567 casos (84,7 %), con mayor incidencia en el rango de edad de 20 a 39 años (39,2 %), el promedio de edad fue de 32,8 años, siendo la etiología más frecuente los accidentes motociclísticos (26,6 %). En el momento de la admisión de acuerdo al ECG hubo una predominancia de TCE leve (32,5 %). En cuanto a la procedencia, 331 (49,5 %) eran del municipio de Cuiabá. Del total de víctimas, 479 (71,6 %) evolucionaron hasta tener el alta hospitalaria. Se registró una prevalencia elevada de TCE en el HPSMC, con predominancia de víctimas adultas jóvenes de sexo masculino, siendo los accidentes motociclísticos la principal causa.

Assessment of intracanal medications cytotoxicity on L929 fibroblast cells / Avaliação da citotoxicidade de medicamentos intracanais em fibroblastos L929

This study aimed to evaluate the cytotoxicity of intracanal medications on L929 fibroblast cells at different periods of observation. The following experimental groups were studied: calcium hydroxide with camphorated paramonochlorophenol and glycerin (CPG); iodoform with glycerin (IG); calcium hydroxide with iodoform and distilled water (CIW); iodoform with distilled water (IW); calcium hydroxide with distilled water (CW); Otosporin ® (OT); and a control group composed of cells and culture medium. Eluates were prepared from each group and placed in contact with 1 x 105 cells/well for periods of 30 minutes, 12, 24, 48 and 72 hours, 5 and 7 days. After each experimental period, a cytotoxicity test was performed using methyltetrazolium (MTT) and a spectrophotometer at an optical density of 570 nm to analyze cell viability. The ANOVA and Tukey test with a significance level of 5% was used to analyze the data. At 30 minutes and at 12 hours, all groups were equal to the control group. At 24 hours, there was greater cytotoxicity in the IG group than in the control group (P<0.001). At 48 hours, only the OT group was cytotoxic (P <0.001). At 72 hours and at 5 days, the most cytotoxic groups were CW and OT. At 7 days, the IW and CPG groups were the least cytotoxic (P <0.001). With respect to experimental time, significant differences between 24 hours and 7 days were observed in all groups. Otosporin® was the most cytotoxic medication, followed by calcium hydroxide with distilled water.

Este estudo teve como objetivo avaliar a citotoxicidade de medicações intracanais em células L929 de fibroblastos em diferentes períodos de observação. Os seguintes grupos experimentais foram estudados: hidróxido de cálcio com paramonoclorofenol canforado e glicerina (CPG); iodofórmio com glicerina (IG); hidróxido de cálcio com iodofórmio e água destilada (CIW); iodofórmio com água destilada (IW); hidróxido de cálcio com água destilada (CW); Otosporin® (OT); e um grupo controle composto por células e meio de cultura. Os eluatos foram preparados a partir de cada grupo e colocados em contato com 1 x 105 células/poço, por períodos de 30 minutos, 12, 24, 48 e 72 horas, 5 e 7 dias. Depois de cada período experimental, um teste de citotoxicidade foi realizado utilizando metiltetrazólio (MTT) e um espectrofotômetro a uma densidade óptica de 570 nm para analisar a viabilidade celular. A análise de variância e o teste de Tukey com nível de significância de 5% foi utilizado para analisar os dados. Em 30 minutos e em 12 horas, todos os grupos foram iguais ao grupo controle. Em 24 horas, houve uma maior citotoxicidade no grupo IG do que no grupo controle (P<0,001). Em 48 horas, apenas o grupo OT foi citotóxico (P<0,001). Em 72 horas e em 5 dias, os grupos mais citotóxicos foram CW e OT. Aos 7 dias, os grupos IW e CPG foram os menos citotóxicos (P<0,001). Com relação ao tempo experimental, foram observadas diferenças significativas entre 24 horas e 7 dias em todos os grupos. Conclusão: Otosporin® foi o medicamento mais citotóxico, seguido de hidróxido de cálcio com água destilada.

Improvement of bone repair in diabetic rats subjected to ƛ780 nm low-level laser therapy

PURPOSE: To investigate the effect of low-level laser therapy on bone healing in diabetic rats.METHODS: Bone cavities (19 mm diameter) were performed in the femur of 72 alloxan-induced diabetic rats, which were assigned into four groups: CTR (non-diabetic control), DBT (diabetic) CTRL (non-diabetic irradiated) and DBTL (diabetic irradiated). Low-level laser therapy was performed every 48h for seven days. Animals were euthanized at seven, 18 and 30 days. Alkaline phosphatase serum levels and bone repair were analyzed.RESULTS: Low-level laser therapy significantly increased alkaline phosphatase in at seven and 18 days (p<0.001), and improved bone healing at seven (p<0.01), 18 (p<0.05) and 30 (p<0.01) in diabetic animals. In addition, bone healing in irradiated diabetic group was statistically similar to control group at 30 days (p>0.05).CONCLUSION:Low-level laser therapy increased the serum levels of alkaline phosphatase and improved bone healing in alloxan-induced diabetic rats.

Effect of laser therapy on the inflammatory response induced by endodontic medications implanted into the subcutaneous tissue of rats / Efeito da laserterapia na resposta inflamatória induzida por medicamentos endodônticos implantados em tecido subcutâneo de ratos

Introduction: Endodontic medications contain toxic components that cause varying degrees of inflammation. Objective: This study evaluated the effect of laser therapy on the inflammatory response induced by intracanal medications implanted into the subcutaneous tissue of rats using a quantitative analysis of mast cells. Material and Method: Polyethylene tubes containing the medications were implanted in the dorsum of 60 rats divided into six groups, including HS (P.A. calcium hydroxide paste), HL (P.A. calcium hydroxide paste and laser therapy), HPS (P.A. calcium hydroxide paste with camphorated paramonochlorophenol), HPL (P.A. calcium hydroxide paste with camphorated paramonochlorophenol and laser therapy), IS (iodoform with saline) and IL (iodoform with saline and laser therapy). The animals were euthanized eight or fifteen days after surgery, and samples were removed and embedded in paraffin. Histological sections were stained with 0.2% toluidine blue for the quantification of mast cells. Analysis of variance (ANOVA) and Tukey's post-hoc test were applied to determine significant differences in the number of mast cells between groups (p<0.05). Result: There was a decrease in mast cells for the HL, HPL and IL groups when compared with the HS, HPS and IS groups at both time points. There was no statistically significant difference between the HPS and HPL groups at the eight-day time point. Conclusion: Laser therapy was effective at modulating the inflammatory response induced by endodontic medications by significantly reducing the number of mast cells. .

Introdução: Medicamentos endodônticos apresentam componentes tóxicos que provocam algum grau de reação inflamatória. Objetivo: Este estudo avaliou o efeito da laserterapia na resposta inflamatória causada por medicações intracanais, em tecido subcutâneo de ratos, por meio da análise quantitativa de mastócitos. Material e Método: Tubos de polietileno contendo as medicações foram implantados no dorso de 60 ratos, distribuídos em seis grupos: HS (pasta de hidróxido de cálcio P.A.); HL (pasta de hidróxido de cálcio P.A. e laserterapia); HPS (pasta de hidróxido de cálcio P.A. com paramonoclorofenol canforado); HPL (pasta de hidróxido de cálcio P.A. com paramonoclorofenol canforado e laserterapia); IS (iodofórmio e soro fisiológico) e IL (iodofórmio, soro fisiológico e laserterapia). Os animais foram eutanasiados oito e quinze dias após a cirurgia, as peças cirúrgicas foram removidas, processadas para inclusão em parafina e os cortes histológicos corados em Azul de Toluidina 0.2%, para quantificação dos mastócitos. A análise de variância (ANOVA) e o teste de Tukey post hoc foram aplicados para determinar diferenças significativas entre os grupos quanto ao número de mastócitos (p<0.05). Resultado: Nos grupos HL, HPL e IL houve uma diminuição de mastócitos em ambos os períodos experimentais em relação aos grupos HS, HPS e IS, porém não se observou diferença estatística significativa entre o grupo HPS e o HPL aos oito dias. Conclusão: A laserterapia foi eficaz em modular a intensidade da resposta inflamatória induzida pelos medicamentos endodônticos a partir da redução significativa na quantidade de mastócitos. .

Effect of low-level laser therapy on pain levels in patients with temporomandibular disorders: a systematic review

Temporomandibular disorders (TMD) are characterized by the presence of temporomandibular joint (TMJ) and/or masticatory muscle pain and dysfunction. Low-level laser is presented as an adjuvant therapeutic modality for the treatment of TMD, especially when the presence of inflammatory pain is suspected. Objective: To systematically review studies that investigated the effect of low level laser therapy (LLLT) on the pain levels in individuals with TMD. Material and Methods: The databases Scopus, embase, ebsco and PubMed were reviewed from January/2003 to October/2010 with the following keywords: laser therapy, low-level laser therapy, temporomandibular joint disorders, temporomandibular joint dysfunction syndrome, temporomandibular joint, temporomandibular, facial pain and arthralgia, with the inclusion criteria for intervention studies in humans. exclusion criteria adopted were intervention studies in animals, studies that were not written in english, Spanish or Portuguese, theses, monographs, and abstracts presented in scientific events. Results: After a careful review, 14 studies fit the criteria for inclusion, of which, 12 used a placebo group. As for the protocol for laser application, the energy density used ranged from 0.9 to 105 J/cm², while the power density ranged from 9.8 to 500 mW. The number of sessions varied from 1 to 20 and the frequency of applications ranged from daily for 10 days to 1 time per week for 4 weeks. A reduction in pain levels was reported in 13 studies, with 9 of these occurring only in the experimental group, and 4 studies reporting pain relief for both the experimental group and for the placebo. Conclusion: Most papers showed that LLLT seemed to be effective in reducing pain from TMD. However, the heterogeneity of the standardization regarding the parameters of laser calls for caution in interpretation of these results. Thus, it is necessary to conduct further research in order to obtain a consensus regarding the best application protocol for pain relief in patients with TMD.

Estudo preliminar da utilização de otólitos de Cynoscion acoupa sobre o processo de neoformação óssea em ratos / Preliminary study of using otoliths of Cynoscion acoupa upon the process of bone regeneration in rats

INTRODUÇÃO: Otólitos são concrescências calcárias presentes no ouvido interno de peixes. Por serem ricos em minerais considerados essenciais ao processo de mineralização óssea sobre uma matriz proteica (otolina), sugere-se que otólitos poderiam funcionar como biominerais. OBJETIVO: Avaliar a capacidade de regeneração de defeitos ósseos tratados com preparado gelatinoso estéril de otólitos. MATERIAL E MÉTODO: O experimento foi realizado com 20 ratos Wistar, distribuídos aleatoriamente em dois grupos, nos quais se realizou defeito ósseo na tíbia, sendo o grupo 1 (G1) experimental, cujas lojas ósseas foram preenchidas com preparado de otólitos, e o grupo 2 (G2) controle, cujas lojas ósseas não receberam tratamento adicional. Os animais foram sacrificados 14 dias após os procedimentos cirúrgicos; as tíbias foram removidas, fixadas em formalina a 10 por cento, descalcificadas em ácido nítrico a 5 por cento e processadas histologicamente. Antes dos sacrifícios, foram coletadas amostras sanguíneas para avaliação das dosagens séricas de cálcio (Ca) e fosfatase alcalina (Alkp). RESULTADOS: As secções histológicas revelaram que o trabeculado ósseo neoformado mostrou-se mais denso e com atividade osteorreabsortiva periosteal menos conspícua no grupo experimental. Entretanto, não demonstraram diferenças estatisticamente significativas na área de neoformação óssea entre G1 (1,9 ± 0,3 mm²) e G2 (1,5 ± 0,4 mm²) (p = 0,0617). Os parâmetros bioquímicos (Ca e Alkp) apresentaram-se dentro dos limites de normalidade. DISCUSSÃO/CONCLUSÃO: Os dados sugerem que os otólitos podem desempenhar papel adjuvante na dinâmica da regeneração óssea.

INTRODUCTION: Otoliths are calcareous concrescences present in the inner ear of fishes. Since they are rich in minerals considered essential to the bone mineralization process on a protein matrix (otolin), it has been suggested that otoliths may work as biominerals. OBJECTIVE: The objective in this study was to analyze the regeneration capacity of bone defects treated with sterile gelatinous otolith preparation. MATERIAL AND METHOD: The experiment was performed with 20 Wistar rats randomized into two groups, in which a bone defect was inflicted in the tibia. In group 1 (experimental), bone cavities were filled with otoliths. In group 2 (control), bone cavities did not receive any additional treatment. The animals were sacrificed 14 days after surgical procedures. The tibias were removed, fixed in formalin at 10 percent, decalcified in nitric acid at 5 percent and histologically processed. Before sacrifice, blood samples were collected to evaluate serum dosage of calcium (Ca2+) and alkaline phosphatase (Alkp). RESULTS: Histological sections revealed that the newly formed trabecular bone was denser and the periosteal reabsorptive activity was less conspicuous in the experimental group. However, there was no statistically significant difference in the area of bone formation between G1 (1.9 ± 0.3 mm²) and G2 (1.5 ± 0.4 mm²) (p = 0.0617). Biochemical (Ca2+ and Alkp) parameters were within normal range. DISCUSSION/CONCLUSION: These data suggest that otoliths may be an adjuvant to the dynamics of bone regeneration.

Effect of bovine type-I collagen-based films containing red propolis on dermal wound healing in rodent model / Efecto de películas a base de colágeno bovino tipo I que contienen propóleo rojo sobre la cicatrización de la herida cutánea en un modelo roedor

Propolis, an apitherapic product widely employed in natural medicine, presents various biological properties, such as bactericidal and anti-inflammatory activities, but only few reports have looked at the Brazilian red propolis variety. Collagen films have been employed to improve wound healing and some studies have investigated the effect of natural products incorporated into these films. Thus, the aim of this study was to analyze the effect of collagen-based films containing red propolis on wound healing. Therefore, wounds performed in the back of rats were dressed with collagen-based films (G2), and collagen-based films containing red propolis (G3); undressed worked as control (G1). After 3, 7 and 14 days the animals were euthanized, and the wounds were microscopically evaluated. In 7 days, G3 showed switch of the inflammatory profile from acute into chronic, increased plasma cells differentiation, replacement of Type-III for type-I collagen fibers, and better architectural organization of those fibers. Furthermore, a slight tendency for a better epithelization was verified in G3, but it was not statistically significant. Also in 7 days, the microvessels count was higher in G1 than in G2 (p=0.000) and G3 (p=0.001), but similar between the last groups (p=0,15), whereas the microvessels perimeter was higher in G1 than in G2 (p=0.000) and G3 (p=0.002), but equivalent in G2 and G3 (p=0.175) in 14 days. In conclusion, the incorporation of Brazilian red propolis into collagen-based films was able to improve wound healing, probably by modulating the dynamics of the inflammatory evolution and collagen deposition process.

El propóleo es un producto apiterápico ampliamente usado en medicina natural, que presenta diversas propiedades biológicas, como actividad bactericida y anti-inflamatoria, pero pocos informes han examinado la variedad brasileña del propóleo rojo. Películas de colágeno han sido empleadas para mejorar la cicatrización de heridas y en algunos estudios se ha investigado el efecto de los productos naturales incorporados en estas películas. Así el objetivo de este estudio fue analizar el efecto de las películas a base de colágeno que contienen propóleo rojo en la cicatrización de heridas. Heridas realizadas en el dorso de ratas fueron revestidas con películas a base de colágeno (G2) y con películas a base de colágeno con propóleo rojo (G3), heridas sin revestimiento fueron utilizadas como control (G1). Después de 3, 7 y 14 días, las heridas fueron evaluadas microscópicamente. A los 7 días G3 mostró un cambio del perfil de la respuesta inflamatoria de aguda a crónica, con aumento de la diferenciación de las células plasmáticas, sustitución de fibras de colágeno tipo III por tipo I con mejora de la organización arquitectónica de estas fibras. Además, una ligera tendencia a una mejor epitelización se verificó en G3, pero no fue estadísticamente significativa. También a los 7 días, el conteo de microvasos fue mayor en G1 que en G2 (p=0,000) y G3 (p=0,001), pero similar entre los últimos grupos (p=0,15), mientras que el perímetro de los microvasos fue mayor en G1 que en G2 (p=0,000) y G3 (p=0,002), pero equivalente en G2 y G3 (p=0,175) en 14 días. En conclusión, la incorporación de la variedad brasileña de propóleo rojo en películas a base de colágeno fue capaz de mejorar la cicatrización de la herida, probablemente por la modulación de la dinámica de la evolución inflamatoria y del proceso de depósito de colágeno.

Morphological analysis of second-intention wound healing in rats submitted to 16 J/cm 2 λ 660-nm laser irradiation.

Background and Objectives : Low-level laser therapy (LLLT) has been extensively applied to improve wound healing due to some biostimulatory properties presented by laser arrays apparently able to accelerate the cicatricial repair of soft tissue injuries. However, many controversial results have been reported in the literature, probably as a result of the wide sort of different protocols of photobiomodulation employed in those experiments. The goal of this study was to investigate the effect of a low-dose protocol of LLT on the intensity of the inflammatory response and the pattern of collagen fibers' deposition during second-intention wound healing in rodents. Materials and Methods : Standard-sized wounds were carried out in the back of 24 male rats. Half of them underwent LLLT treatment (16 J/cm 2 ) at 660 nm delivered for 7 days. Eight and 14 days after the wounds were performed, the repairing area was removed and stained in HE and Masson's trichrome, and the inflammatory response, epithelization, and collagen fiber depositions were evaluated. Results : We found that LLLT was able to slightly reduce the intensity of the inflammatory reaction as well as to enhance substantially the epithelization process at both 8 th and 14 th days. In addition, it also appeared to stimulate the deposition of collagen fibers at the final stages of wound healing. Conclusions : The LLLT protocol tested in this study resulted in some improvements in second-intention wound healing in rodents.

Effect of low-level laser therapy and mineral trioxide aggregate on alveolar bone repair

Aim: This study aimed to evaluate the effect of low-level laser therapy (LLLT) associated to mineral trioxide aggregate (MTA) on the alveolar bone repair process. Methods: Forty Wistar rats had the upper right incisor extracted and were assigned to 4 groups according to the treatment of the alveolar wound: G1 - no treatment (control group); G2 - sockets were filled with MTA; G2 - sockets were treated with LLLT(l780 nm, 40 mW, 16 J/cm2); and G4 – sockets were treated with LLLT and filled with MTA. The animals were sacrificed 14 days after the surgical procedures. The maxillas were removed, fixed in formalin, decalcified in 0.5% nitric acid and processed histologically. Results: In G1, there was bone formation on the bottom of the socket, but it was not noticeable on the superficial areas, as well as the presence of an intense granulation tissue. In G2, the bone trabeculae were irregular and thin, and were associated with intense vascular hyperemia and chronic inflammation. In G3, there was substantial formation of thick interwoven osteocyte-rich trabecular bone, with an evident osteoblastic rimming. In G4, it was observed an intense deposition of thin irregular bone trabeculae, but vascular hyperemia was quite distinguishable. Conclusion: LLLT was the most successful treatment to improve alveolar bone repair.