Low-level laser therapy (LLLT) benefits bone metabolism, but its use needs to be standardized. We evaluated the effects of LLLT on bone defects in calvaria of ovariectomized rats. Stereology was used to calculate tissue repair volume (V tr ), density of trabecular bone volume (Vv t ), total volume of newly formed trabecular bone (Vtot), and the area occupied by collagen fibers (A C ). Fifty-four Wistar rats were submitted to bilateral ovariectomy, and bone defects were created in calvaria after 150 days. The animals were divided into nine groups (n = 6), and 24 h after defects, the treatment started with a 780-nm low-intensity GaAlAs laser: G1, G2, and G3 received 3 sessions of 0, 20, and 30 J/cm(2) respectively; G4, G5, and G6 received 6 sessions of 0, 20, and 30 J/cm(2), respectively; and G7, G8, and G9 received 12 sessions of 0, 20, and 30 J/cm(2), respectively. A normal distribution was found for all of the data. The test used to verify the normality was the Kolmogorov-Smirnov (KS, p > 0.05). The one-way ANOVA followed by Tukey's post hoc test was used for data processing. A difference of p < 0.05 was considered statistically significant. Groups G2 and G1 showed significance for V tr , Vv t , Vtot, and (A C ). Results were significant for (Vv t ) and (Vtot) between G3 and G1. There were no significant results between G5 and G4 as well as between G8 and G7. Groups G6 and G4 results showed statistical difference for V tr , Vv t , Vtot, and (A C ). Groups G9 and G7 showed significance for V tr , Vv t , Vtot, and (A C ). In conclusion, there was new bone formation in the groups that received 20 and 30 J/cm(2) when compared to control groups, but over time, the dose of 30 J/cm(2) showed better stereological parameters when compared to 20 J/cm(2).

Introdução e objetivo: Frequentemente são encontrados corpos em que a única peça disponível para o processo de identificação humana é o dente, uma das estruturas do corpo humano mais resistentes a alterações ambientais e fatores externos. O presente trabalho objetivou realizar um estudo histológico do elemento dentário e as alterações que podem acontecer no complexo dentina-polpa depois de passados diferentes períodos de inumação, bem como a sua utilidade na prática forense em Odontologia Legal, a fim de verificar a possibilidade de inferência quanto ao tempo decorrente e às modificações histológicas no elemento dentário. Material e métodos: Em recipientes de barro, cobertos por solo comum e mantidos ao ar livre, submeteram-se 48 terceiros molares extraídos a variados tempos de inumação (sete, 30, 60 e 180 dias). Após, os dentes foram retirados e analisados por descalcificação e realizaram-se cortes longitudinais de 6 µm de espessura, corados com hematoxilina-eosina. Depois da montagem dos cortes nas lâminas, efetuaram-se análises histológicas da dentina e do cemento. Resultados: A análise qualitativa em microscópio de luz possibilitou ver que as partes mineralizadas dos dentes apresentavam bom estado de conservação (cemento e dentina). No entanto tecidos moles, como polpa dentária e ligamento periodontal, estavam fragmentados e, na maioria das vezes, ausentes. Conclusão: Adentina e o cemento não tiveram alterações histológicas significativas, não permitindo nenhuma inferência quanto ao tempo decorrente da inumação.

We thank Dr. Xu for this opportunity to better clarify the use of the t-test for microarray data analysis and we are happy that our results are useful.Firstly, t-test when used for microarray data analysis corresponds to a version adapted for large-scale data and not the classical t-test for experiments that generate a small set of data. The Agilent Gene Spring platform (www.agilent.com/ cs/library/usermanuals/Public/GeneSpring-manual.pdf) that we used in this study provides the version of t-test suitable for microarray data analysis, including hypothesis test correction (Benjamini-Hochberg correction or FDR).Secondly, we used unpaired t-test considering that Wistar rats consist of an outbred strain of rats and in this case, the experiments were organized into two different types of groups, the control and the treated group of animals. The adequate option for this type of experiment is using unpaired t-test. Our raw data are freely available at the ArrayExpress (www.ebi.ac.uk/arrayexpress) under the acc numbers E-MTAB-3564 for mRNA data and E-MTAB-3563 for miRNA data. This offers the possibility for researchers to make use of these data for further analysis using different statistical tests or comparisons between groups.Thank you.