RESUMO Objetivos: Conhecer as justificativas de familiares para a não autorização da doação de órgãos e tecidos. Métodos: Trata-se de um estudo documental. Analisaram-se os registros de entrevistas familiares de potenciais doadores, realizadas em 2022 por uma Organização de Procura de Órgãos e Tecidos (OPO) do estado do Rio Grande do Sul. Foram incluídos no estudo os registros referentes às negativas para a doação. Registros incompletos ou que careciam da justificativa dos familiares foram excluídos. Os dados foram coletados em março e abril de 2024 e analisados por meio de estatística descritiva simples. O projeto de pesquisa foi aprovado pelo Comitê de Ética em Pesquisa. Resultados: Durante 2022, a OPO pesquisada realizou 121 entrevistas com familiares de potenciais doadores de órgãos; desse total, houve 33 autorizações, 65 negativas e 23 casos de contraindicação médica para a doação. Quanto às negativas dos familiares, dos 65 registros analisados, 39 foram excluídos, pois estavam com informações incompletas ou não continham a justificativa para a não doação. A amostra final foi constituída por 26 registros de entrevistas. Os argumentos mais comuns para a negativa à doação foram paciente não era doador em vida, desconhecimento da família sobre o desejo do falecido quanto à doação e manifestação contrária da família. Conclusão: Entre as justificativas observadas estão a pessoa falecida ter se declarado não doadora em vida, a falta de consenso familiar acerca da doação, o desejo da família em preservar a integridade do corpo, o tempo de espera para a devolução do corpo, aspectos religiosos, o desconhecimento quanto ao desejo do falecido acerca da doação e a família ser contrária à doação. Os resultados poderão ser utilizados por profissionais em diferentes serviços de saúde para a criação de estratégias de mitigação das negativas dos familiares. Objetivos tecidos Métodos Tratase Trata documental Analisaramse Analisaram 202 (OPO Sul excluídos simples Pesquisa Resultados 12 total 3 autorizações 6 2 vida Conclusão corpo religiosos 20 1

ABSTRACT Objectives: To understand the reasons given by family members for not authorizing the donation of organs and tissues. Methods: This is a documentary study. The records of interviews with the families of potential donors, conducted in 2022 by the Organ and Tissue Procurement Organization in the state of Rio Grande do Sul, were analyzed. The study included records related to refusals for donation. Incomplete records or those lacking the family's justification were excluded. Data were collected in March and April 2024 and analyzed using simple descriptive statistics. The research project was approved by the Research Ethics Committee. Results: During 2022, the OPO conducted 121 interviews with family members of potential organ donors; of this total, there were 33 authorizations, 65 refusals, and 23 cases of medical contraindications for donation. Regarding family refusals, of the 65 records analyzed, 39 were excluded due to incomplete information or because they did not contain the justification for refusal. The final sample consisted of 26 interview records. The most common arguments for refusing donation were the patient was not a donor in life, the family was unaware of the deceased’s wishes regarding donation, and the family expressed opposition to donation. Conclusion: The observed justifications included the deceased having declared themselves not to be a donor in life, lack of family consensus on donation, the family’s desire to preserve the integrity of the body, the wait time for the return of the body, religious reasons, unawareness of the deceased’s wishes regarding donation, and family opposition to donation. The results may be used by professionals in various healthcare services to develop strategies to mitigate family refusals. Objectives tissues Methods donors 202 Sul familys s statistics Committee Results 12 total 3 authorizations 6 2 refusal life deceaseds Conclusion body 20 1

Abstract Objective: To describe study protocol and initial results of research project COVID-Inconfidentes. Method: This paper described the methodological procedures adopted and the prevalence of the SARS-CoV-2 infection in the population. A household survey was conducted between October and December 2020, in two historic cities of Brazil's mining region. Anti-SARS-CoV-2 antibody was detected using the Wondfo® rapid test. The face-to face interview consisted of administration of a questionnaire containing registration data, sociodemographic and economic variables, living habits, general health condition, mental health, sleep habits, and eating and nutrition. Results: We evaluated 1,762 residents, of which 764 (43.4 %) were in Mariana and 998 (56.6 %) in Ouro Preto. For both cities, 51.9 % of the interviewees were female, with a predominance of the age range 35 to 59 years old (47.2 %). The prevalence of the SARS-CoV-2 infection was 5.5 % in both cities, 6.2 % in Ouro Preto, and 4.7 % in Mariana (p-value > 0.05). Conclusion: The study was effective to estimate the seroprevalence of infection by the virus and its findings will enable further analyses of the health conditions of the population related to social isolation and the risk of infection with SARS-CoV-2.

Resumen Describir el protocolo de estudio y los resultados iniciales del proyecto de investigación COVID Inconfidentes. Método: Este artículo describe los procedimientos metodológicos adoptados y la prevalencia de la infección por SARS-CoV-2 en la población. Se realizó una encuesta domiciliaria entre octubre y diciembre de 2020, en dos ciudades históricas de la región minera de Brasil. El anticuerpo anti-SARS-CoV-2 se detectó mediante la prueba rápida Wondfo®. La entrevista cara a cara consistió en la administración de un cuestionario que contenía datos de registro, variables sociodemográficas y económicas, hábitos de vida, estado general de salud, salud mental, hábitos de sueño, alimentación y nutrición. Resultados: Se evaluaron 1.762 habitantes, de los cuales 764 (43,4 %) estaban en Mariana y 998 (56,6 %) en Ouro Preto. Para ambas ciudades, el 51,9 % de los entrevistados eran del sexo femenino, con predominio del rango de edad de 35 a 59 años (47,2 %). La prevalencia de la infección por SARS-CoV-2 fue del 5,5 % en ambos municipios, del 6,2 % en Ouro Preto y del 4,7 % en Mariana (p > 0,05). Conclusión: El estudio fue efectivo para estimar la seroprevalencia de infección por el virus y sus hallazgos permitirán analizar más las condiciones de salud de la población relacionadas con el aislamiento social y el riesgo de infección por SARS-CoV-2.

ABSTRACT The aim of this study was to estimate the rate of Mother-to-child Transmission (MTCT) of HIV to neonates in a reference university hospital in Sao Luis city, the capital of Maranhao State (MA), evaluating MTCT-associated factors. A retrospective cohort study based on data from the Notifiable Diseases Data System (SINAN) was carried out and included all HIV-exposed neonates notified from 2013 to 2017 by the university hospital. The study population comprised 725 HIV-exposed neonates, of whom 672 neonates were exposed and uninfected, and 53 were exposed and infected. The estimated rate of MTCT in the period of 2013 to 2017 was 7.3%. Most pregnant women were ≥ 20 years old (86.9%), reported ≥ 8 years of schooling (53.2%), reported full-time or independent paid work (46.9%) and were residents in other cities of the state (61.7%). Regarding healthcare, 86.3% received prenatal care, 74.6% received Antiretroviral Therapy (ART) as prophylaxis during pregnancy, 81.8% received ART prophylaxis during childbirth and 78.1% underwent cesarean section. Among the neonates, 92.8% received ART prophylaxis and 94.3% were not breastfed. Despite these variables, the 7.3% MTCT rate found in this study makes it clear that the interventions recommended by the Ministry of Health were not fully adopted. Mothertochild Mother child (MTCT city MA, MA , (MA) MTCTassociated associated factors SINAN (SINAN HIVexposed 201 72 67 uninfected 5 infected 73 7 3 2 86.9%, 869 86.9% 86 9 (86.9%) 53.2%, 532 53.2% (53.2%) fulltime full time 46.9% 469 46 (46.9% 61.7%. 617 61.7% . 61 (61.7%) healthcare 863 86.3 care 746 74 6 74.6 (ART pregnancy 818 81 81.8 781 78 1 78.1 section 928 92 92.8 943 94 94.3 breastfed variables 7.3 adopted (MA 86.9 (86.9% 53.2 (53.2% 46.9 4 (46.9 61.7 (61.7% 86. 74. 81. 78. 92. 94. 7. (86.9 53. (53.2 46. (46. 61. (61.7 (86. (53. (46 (61. (86 (53 (4 (61 (8 (5 ( (6

Abstract Emerging evidence has revealed a cross-talk in the etiopathogenesis of burning mouth syndrome (BMS) related to peripheral nerve fibers (NF) and neuropeptides secreted by mast cells. Here, we investigated the S-100+ density and PGP 9.5+ integrity of peripheral NF and the tryptase+ mast cell density in the oral mucosa of BMS patients and healthy individuals. A total of 23 oral mucosa specimens (12 BMS and 11 controls) were evaluated. The clinical diagnosis of BMS was based on a careful examination, excluding other local and systemic causes. Samples were taken from an incisional biopsy of the tongue mucosa of individuals with symptomatic BMS, while the margins of the non-neoplastic tongue biopsy served as controls of healthy individuals. Immunohistochemistry was performed to determine the density/mm2 of S-100+, PGP 9.5+ peripheral NF, and tryptase+ mast cells. Similar densities of S-100+, PGP 9.5+ peripheral NF, and tryptase+ mast cells were found in cases of BMS, with a median value of 3.70, 0.70, and 29.24/mm2, respectively, and in the control group, with a median value of 2.60, 0.80, and 26.01/mm2, respectively (p > 0.05). Moreover, the relationship between S100+ and PGP 9.5+ peripheral NF was the same in both groups (p = 0.70). This study demonstrated that there were no alterations in the density and integrity of peripheral NF in the tongue of symptomatic BMS patients. However, the sensitization of peripheral NF in this disease may not depend on mast cell density. crosstalk cross talk (BMS (NF Here S100 S 100+ 100 S-100 95 9 5 9.5 tryptase 2 12 (1 1 evaluated examination causes nonneoplastic non neoplastic densitymm2 densitymm mm2 mm density/mm S100+, 100+, 370 3 70 3.70 070 0 0.70 2924mm2 29 24 29.24/mm2 group 260 60 2.60 080 80 0.80 2601mm2 26 01 26.01/mm2 p 0.05. 005 0.05 . 05 0.05) Moreover 0.70. 0.70) However S10 10 S-10 9. ( 37 7 3.7 07 0.7 2924mm 29.24/mm 6 2.6 08 8 0.8 2601mm 26.01/mm 00 0.0 S1 S-1 3. 0. 2. S-

Resumo Dar más notícias é comum em obstetrícia e ginecologia. Porém, é difícil e poucos médicos recebem treinamento sobre como lidar com essa situação. Esta revisão narrativa tem como objetivo reunir, analisar e sintetizar parte do conhecimento sobre a área, com foco na obstetrícia. Dentre os 16 artigos selecionados, dois são estudos de intervenção randomizados e controlados, e a maioria dos estudos refere-se à obstetrícia. Os resultados encontrados ressaltaram que simulação, feedback/entrevistas, palestras e protocolos podem melhorar o desempenho dos médicos na comunicação de más notícias. Para os pacientes, o contexto e como as informações são transmitidas parecem ter maior impacto do que o conteúdo das notícias. Os obstetras e ginecologistas poderiam se beneficiar de cursos e protocolos específicos, dadas as particularidades da especialidade. Faltam evidências sobre a forma mais eficaz de realizar esse treinamento. Encontrar formas validadas de quantificar e classificar os resultados dos estudos na área, permitindo uma análise objetiva dos resultados, é um dos maiores desafios neste tema.

Abstract Breaking bad news is common in obstetrics and gynecology (ob-gyn). However, it is difficult, and few doctors receive training on how to deal with this situation. This narrative review aims to gather, analyze, and synthesize part of the knowledge on the area, focused on Ob-Gyn. Among the 16 selected articles, two are randomized controlled intervention studies, and most studies refer to obstetrics. The results found by us pointed out that simulation, feedback/debriefing, lectures, and protocols could improve doctors’ performance in communicating bad news. For patients, the context and how the information is transmitted seem to impact more than the content of the news. Ob-Gyn doctors could benefit from specific protocols and education, given the specialty’s particularities. There is a lack of evidence about the most effective way to conduct such training. Finding validated ways to quantify and classify studies’ results in the area, which would allow for the objective analysis of outcomes, is one of the biggest challenges concerning this topic.

Abstract: There is a lack of evidence on the correlation between salivary biomarkers and subjective measures of dental fear and anxiety in children. This systematic review aimed to retrieve the scientific evidence comparing the results of dental anxiety measured by salivary biomarkers with patient-reported outcomes in pediatric dental setting. The PECOS was as follows: population: pediatric patients aged ≤ 18 years; exposure: patient-reported outcome measures, such as scales and/or questionnaires; comparator: salivary biomarkers; outcome: anxiety, fear, phobia or stress during dental treatment; study design: observational studies or controlled trials. Electronic searches were conducted in PubMed, Scopus, Web of Science, and Ovid databases. Studies that compared scales/questionnaires and salivary biomarkers for the evaluation of dental anxiety, fear, and stress in children/adolescents during dental treatment were included. Certainty of evidence was assessed with GRADE. Risk of bias of the included studies was assessed with the Cochrane tool or the University of Adelaide tool. From the 314 studies identified, eight were included. Participants’ age ranged from three to 13 years. The most used salivary biomarkers and instruments were cortisol and the Dental Subscale of the Children's Fear Survey Schedule, respectively. Most studies showed a weak correlation between objective and subjective measures. The main issues regarding bias were on allocation concealment, blinding of assessors, follow up, and exposure assessment. Certainty of evidence was low/very low. Evidence of salivary biomarkers and patient-reported outcome measures to investigate anxiety, fear and stress in children during in the dental environment is limited. There was no correlation between subjective and objective measures in almost all included studies.

Background: A population study is an important tool that can be used to understand the actual epidemiological scenario of the Covid-19 in different territories, identify its magnitude, understand its transmission dynamics, and its demographic, geographical, and social distribution. Objective: The aim of this study was to determine the prevalence and dynamics of SARS-CoV-2 infection in the population of two Brazilian cities during the pandemic first wave and subsequent socioeconomic and health effects. Materials & methods: This paper described the methodological procedures adopted and the prevalence of the SARS-CoV-2 infection in the population. A household survey was conducted between October and December 2020, in two historic cities of Brazil's mining region. Anti-SARS-CoV-2 antibody was detected using the Wondfo® rapid test. The face-to-face interview consisted of administration of a questionnaire containing registration data, sociodemographic and economic variables, living habits, general health condition, mental health, sleep habits, and eating and nutrition. Results: We evaluated 1,762 residents, of which 764 (43.4%) were in Mariana and 998 (56.6%) in Ouro Preto. For both cities, 51.9% of the interviewees were female, with a predominance of the age range 35 to 59 years old (47.2%). The prevalence of the SARS-CoV-2 infection was 5.5% in all cities, 6.2% in Ouro Preto, and 4.7% in Mariana. The prevalence was similar between cities (P>0.05). Conclusion: The study was effective in verifying the seroprevalence of infection by the virus and its findings will enable further analyses of the health conditions of the population related to social isolation and the risk of infection with SARS-CoV-2.

Abstract: FITOPROT, which contains curcuminoids and Bidens pilosa L. extract, is an innovative mucoadhesive formulation indicated for the topical treatment of chemoradiotherapy-induced oral mucositis (OM) in patients with advanced and visible oral squamous cell carcinoma. The formulation is used as a mouthwash directly on tumor tissue of patients with advanced neoplasms, without triggering cancer cell proliferation or tumor invasiveness. Thus, the aim of this study was to evaluate the biological effects of FITOPROT on an oral squamous cell carcinoma cell line (SCC-4). The viability of SCC-4 cells was assessed after exposure to FITOPROT using MTT reduction assay. The effects of the mucoadhesive formulation on cell cycle progression and cell death parameters were evaluated using flow cytometry. In addition, the inflammatory profile of the tumor cells was evaluated using the cytometric bead array (CBA) assay. FITOPROT promoted a concentration-dependent decrease in cell viability and cell cycle arrest at the G2/M phase (p < 0.05). Mitochondrial membrane potential was also altered after exposure to the formulation (p < 0.05), in parallel with a reduction in VEGF and IL-8 production (p = 0.01 and p = 0.05, respectively). In summary, the results indicate that FITOPROT reduces SCC-4 cell viability, promotes cell cycle arrest, modulates mitochondrial membrane potential, and exhibits antiangiogenic and anti-inflammatory properties, thus indicating its potential for topical use in patients with OM and visible tumors in the mouth.

abstract background: the recovery of areas impacted by mining activities is a major challenge and requires knowledge of how the biological and biochemical processes of the soil as well as the establishment of plant species are affected by mining residue. in this work, the influence of deposition of iron mining mud and tailings on soil biochemical attributes and the initial development of tree seedlings was studied in a simulated event in the greenhouse. pots (n = 27) with natural soil (2.0 kg) received deposition (280 ml) of iron mining mud or tailings and by three-month was cultivated with urochloa decumbens. at the end of this period, part of the pots was sampled and the soil biochemical activities were evaluated. then tree seedlings (schinus terebinthifolius and eremanthus incanus) were planted and cultivated for a year, when then shoot (sdw) and roots (rdw) dry weight were evaluated. results: deposition of iron mining mud and tailings did not affect microbial biomass carbon or basal soil respiration, however both conditions reduced (p < 0.05) β-glucosidase activities by up to 30%, and the easy extractable glomalin by about 19%. in addition, the mud deposition reduced (p < 0.05) the sdw and rdw of s. terebinthifolius by about 21% and 24%, respectively. nevertheless, uruchloa decumbens and eremanthus incanus had no variation in dry weight production between treatments, so they have good ability to grow settle in soil affected by mining residue. conclusion: this study shows that the sequential planting of u. decumbens and e. incanus can be an alternative for use in environments with deposition of iron mining tailings.

RESUMO Objetivo investigar a forma de oferta de dieta, conforme os diversos métodos de alimentação, e descrever o ganho de peso em recém-nascidos com microcefalia relacionada ao Zika Vírus, comparando-os com recém-nascidos sem microcefalia. Método estudo de coorte retrospectivo com caso controle aninhado. Informações sobre idade gestacional, peso e métodos de alimentação (seio materno, sonda nasogástrica/orogástrica, mamadeira e copo) foram coletadas em prontuários de 43 recém-nascidos com microcefalia por Zika Vírus, equiparados conforme idade gestacional com 43 recém-nascidos sem acometimentos (grupo controle), em uma maternidade de referência no Nordeste do Brasil. Os dados foram coletados desde o nascimento até a alta hospitalar. As medidas de desfecho foram pesos (ao nascer e na alta), velocidade de ganho de peso, tempo de internação e métodos de alimentação. Resultados O grupo com microcefalia apresentou menores pesos ao nascer (D=-1,67; p<0,001), inclusive com maior probabilidade de serem baixo peso (Phi=0,687; p<0,001), e no momento da alta (D=-0,87; p=0,006), do que o controle. O grupo com microcefalia também apresentou maior velocidade de ganho de peso (D=0,77; p=0,006), embora com métodos alimentares semelhantes ao grupo controle, incluindo a aceitação do seio materno, de forma exclusiva (34,9%) ou complementada (58,1%). Conclusão recém-nascidos com microcefalia relacionada ao Zika Vírus utilizaram métodos alimentares semelhantes, incluindo seio materno, aos do grupo sem acometimento. Quanto ao peso, apresentaram valores menores ao nascimento e na alta, apesar de terem um crescimento precoce pós-natal mais rápido que aqueles sem microcefalia.

ABSTRACT Purpose Investigate the form of diet offer, according to the different feeding methods, and describe the weight gain in newborns with microcephaly related to Zika Virus, comparing them with newborns without microcephaly. Methods Retrospective cohort with nested case-control study. Information on gestational age, weight and feeding methods (maternal breast, nasogastric/orogastric tube, bottle and cup) were collected from medical records of 43 newborns with microcephaly due to Zika Virus, matched according to gestational age with 43 newborns without involvement (control group), in a reference maternity hospital in northeastern Brazil. Data were collected from birth to hospital discharge. Outcome measures were weights (at birth and at discharge), weight gain speed, length of hospital stay and feeding methods. Results The microcephaly group had lower weights at birth (D=-1.67; p<0.001), even more likely to be underweight (Phi=0.687; p<0.001), and at discharge (D=-0.87; p=0.006), than the control group. The microcephaly group also showed a higher rate of weight gain (D=0.77; p=0.006), although with eating methods similar to the control group, including acceptance of the mother’s breast, exclusively (34.9%) or complemented (58.1%). Conclusion Newborns with Zika Virus-related microcephaly used similar feeding methods, including maternal breast, to those in the non-affected group. As for weight, they showed lower values at birth and at discharge, despite having a faster postnatal early growth than those without microcephaly.

Abstract The aim of this study was to investigate the epidemiological and clinical characteristics of chronic inflammatory periapical diseases in different regions of Brazil and to compare with data from the literature. A multicenter study was carried out in four Brazilian referral centers in oral diagnosis. Histopathological records were reviewed, and all cases diagnosed microscopically as periapical granuloma, radicular cyst, and periapical abscess were included. Demographic and clinical data were collected. Descriptive statistics and Pearson’s chi-square test were performed. A total of 10,381 cases of chronic inflammatory periapical diseases were found (13.8% of 74,931 archived specimens) over a period of 65 years. Radicular cysts were the most common lesion (59.9%). Women (56.1%) with a mean age of 37.01 years old (range 13 to 100 ± 14.42) and people of white skin color (59.2%) were the most affected individuals by chronic inflammatory periapical diseases. The lesions were generally asymptomatic (28.1%), located in the maxilla (60.1%), and posterior region (49.8%). The radicular cysts were larger when compared to periapical granulomas (p < 0.001). The disagreement between the clinical and histopathological diagnoses was higher when the final diagnosis was a periapical granuloma (p < 0.001). Chronic inflammatory periapical diseases continue to be common lesions affecting mainly adults. This should be a consequence of the burden of untreated caries in permanent teeth. Women are more affected and radicular cyst was the most common lesion.

Abstract Regulatory T (Treg) cells can suppress antitumor immune response, but little is known about possible age-related differences in the number of these cells in the microenvironment of oral tongue squamous cell carcinoma (OTSCC). The aim of this study was to determine the number of FoxP3+ Treg cells in the microenvironment of OTSCC in young (≤ 45 years) and older (≥ 60 years) patients, and to correlate the findings with clinicopathological parameters (sex, tumor size/extent, regional lymph node metastasis, clinical staging, and histopathological grade of malignancy). Forty-eight OTSCCs (24 diagnosed in young patients and 24 diagnosed in older patients) were selected. Lymphocytes exhibiting nuclear immunopositivity for FoxP3 were quantified at the tumor invasive front and the results were analyzed statistically using the non-parametric Mann-Whitney test. FoxP3+ lymphocytes were observed in all cases assessed. The number of FoxP3+ lymphocytes in OTSCC tended to be higher in older patients (p = 0.055). Analysis of OTSCC in males and in early clinical stages revealed a higher number of Treg cells in older patients than in young ones (p < 0.05). In older patients, the number of Treg cells tended to be higher in smaller tumors (p = 0.079). Tumors with intense inflammatory infiltrate exhibited a larger number of Treg cells, both in young (p = 0.099) and older patients (p = 0.005). The results suggest a greater participation of Treg cells in immunoinflammatory responses in the microenvironment of OTSCC in older patients, particularly in males and in early stages.

Resumo Pouco se sabe sobre o impacto de um delineamento cruzado nos desfechos de ensaios clínicos randomizados voltados ao comportamento de crianças durante tratamento odontológico. Este estudo objetivou avaliar o efeito da sequência de administração do sedativo, da droga em si e da idade dos participantes no comportamento de crianças que receberam duas consultas odontológicas consecutivas. Dezoito crianças saudáveis não colaboradoras, 2-5 anos de idade, foram randomizadas em dois grupos: G1 - 1,0 mg/kg midazolam oral (primeira sessão) e placebo oral (segunda sessão); G2 - placebo (primeira) e 1,0 mg/kg midazolam oral (segunda). Um observador treinado avaliou o comportamento infantil. Os dados foram analisados por ANOVA de três fatores (alfa=0,05). Midazolam [média(DP); 71,7%(16,5)] e placebo [48,6%(33,1)] resultaram em mais comportamento não cooperativo quando administrados na primeira sessão comparado com a segunda (p=0,001). Com o uso do placebo, crianças de 2-3 anos de idade exibiram mais comportamento não cooperativo [G1 54,9%(36,2); G2 80,5%(8,3)] que as de 4-5 anos de idade (p=0,04). Além disso, a porcentagem de redução do comportamento não cooperativo foi maior em crianças mais velhas em G1 (76,2%) e em crianças mais novas em G2 (32,9%). Considerando a avaliação do comportamento infantil sob sedação, a primeira sessão odontológica influenciou a segunda visita. Os resultados deste estudo confirmam a especulação de que o delineamento cruzado é inadequado para avaliar o comportamento odontológico relacionado à ansiedade/comportamento infantil; os resultados dos ensaios cruzados de sedação odontológica devem ser tratados com extrema cautela.

Abstract Crossover studies continue to be published in spite of warnings about their inherent risks in relation to behavioral outcomes. This study took the opportunity of access to secondary data analysis in order to demonstrate the impact of a crossover design on the outcomes of randomized clinical trials aimed at the behavior of children during dental treatment. We evaluated the effect of the sequence of sedative administration, the sedative and the participant’s age on the behavior of children undergoing two sequential dental visits. Eighteen uncooperative healthy young children were equally randomly assigned to: (G1) 1.0 mg/kg oral midazolam (first session) and oral placebo (second session); (G2) oral placebo (first) and 1.0 mg/kg oral midazolam (second). One trained observer assessed children’s behavior. Data were analyzed by three-way mixed ANOVA. Both midazolam [mean(SD); 71.7%(16.5)] and placebo [48.6%(33.1)] produced more struggling behavior when they were administered in the first session compared to the second one (p=0.001). For the placebo, children aged 2-3 years exhibited more struggling behavior [G1 54.9%(36.2); G2 80.5%(8.3)] than those aged 4-5 years (p=0.04). Also, the reduction of percentage of struggling behavior was higher in G1 for older children (76.2%) and in G2 for younger children (32.9%). There were significant interactions between drug and sequence of administration, and between drug and age. The results of our study confirm the conventional wisdom that crossover study design is inappropriate to evaluate children’s behavior/anxiety related-dental treatment under sedation and the results of crossover studies of dental sedation should be treated with extreme caution.