ABSTRACT BACKGROUND AND OBJECTIVES: Since the relatively recent discovery of the endocannabinoid system (ECS) and its fundamental role in regulating other systems, the subject has aroused interest in all areas of health, including Dentistry. Among the possible uses and benefits of cannabinoids are their performance in pain and its predisposing or perpetuating factors, such as bruxism and sleep disorders. Although the literature is still scarce, the mechanisms of action and satisfactory results of cannabinoids and other cannabis derivatives in these situations already allow their safe prescription. The objective of this study was to verify the current evidence on the use of cannabis derivatives in orofacial pain (OFP), reviewing what is known, to date, about the ECS and the prospects for its use with support and criteria. CONTENTS: This research carried out a brief review of the cannabis plant history, addressing issues such as prejudice, prohibitions and interests, as well as its therapeutic use. Then, a review on ECS and its mechanisms of interest in OFP was presented. Next, the products derived from the plant and their effects, indications, contraindications, adverse effects, drug interactions, peculiarities and perspectives were discussed. CONCLUSION: The more knowledge is gained about the ECS and the therapeutic benefits of cannabis components and derivatives, the greater the conviction that a new therapeutic frontier has indeed emerged. The growing number of good outcomes, including cases of OFP, obtained through well-conducted studies, brings a mixture of satisfaction and excitement. No therapy will achieve good results if it does not start from an accurate diagnosis. Thus, it is of the utmost importance to know the ECS, the products and derivatives of the plant, the synthetic cannabinoids, their indications and effects. New studies are necessary and, at this moment, it can be said that the perspectives are very good and a new and challenging horizon is emerging.

RESUMO JUSTIFICATIVA E OBJETIVOS: Desde a descoberta relativamente recente do sistema endocanabinoide (SEC) e seu papel fundamental da regulação de outros sistemas, o assunto tem despertado interesse de todas as áreas da saúde, incluindo-se a Odontologia. Dentre as possíveis utilizações e benefícios dos canabinoides, está sua atuação na dor e seus fatores predisponentes ou perpetuadores, como o bruxismo e os distúrbios do sono. Embora a literatura seja ainda escassa, os mecanismos de ação e resultados satisfatórios dos canabinoides e demais derivados da cannabis nessas situações já permitem sua prescrição com segurança. O objetivo deste estudo foi verificar as atuais evidências sobre a utilização de derivados da cannabis nas dores orofaciais (DOFs), revisando o que se sabe, até o momento, sobre o SEC e as perspectivas de sua utilização com respaldo e critério. CONTEÚDO: Esta pesquisa realizou uma breve revisão da história da planta cannabis, abordando temas como preconceito, proibições e interesses, além de sua utilização terapêutica. Em seguida, foi apresentada uma revisão sobre o SEC e seus mecanismos de interesse na DOF. Na sequência, foram discutidos os produtos derivados da planta e seus efeitos, indicações, contraindicações, efeitos adversos, interações farmacológicas, peculiaridades e perspectivas. CONCLUSÃO: Quanto mais são adquiridos conhecimentos sobre o SEC e os benefícios terapêuticos dos componentes e derivados da cannabis, mais há um convencimento de que surgiu, de fato, uma nova fronteira terapêutica. O número crescente de bons desfechos, incluindo casos de DOF, obtidos através de estudos bem conduzidos, traz um misto de satisfação e empolgação. Nenhuma terapia obterá bons resultados se não partir de um diagnóstico preciso. Assim, é de suma importância que se conheça o SEC, os produtos e derivados da planta, os canabinoides sintéticos, suas indicações e efeitos. Novos estudos são necessários e, nesse momento, pode-se afirmar que as perspectivas são muito boas e um novo e desafiador horizonte está despontando.

Abstract Lipolytic substance injections to reduce localized fat have been extensively used because it is a low-invasive method. This review aimed to evaluate the efficacy and safety of deoxycholic acid in submental fat reduction compared to a placebo and investigate the potential industry sponsorship bias in the results of randomized clinical trials on this topic. Ten electronic databases were extensively searched for randomized clinical trials without restriction on language and year of publication. Two reviewers extracted the data and assessed the individual risk of bias in the studies with the RoB 2.0 tool. The industry sponsorship bias was evaluated according to citations in the articles regarding industry funding/sponsorship throughout the texts. Fixed and random effects meta-analyses were performed, and the results were reported in Risk Ratio (RR) at a 95% Confidence Interval (95% CI). The initial search provided 5756 results, of which only five were included. Only two studies had a low risk of bias. All studies showed a potential industry bias. The meta-analysis showed that patients treated with deoxycholic acid had significant positive results for all efficacy outcomes and a higher risk of fibrosis, pain, erythema, numbness, swelling, edema, pruritus, nodules, headache, and paresthesia. The low to moderate certainty of evidence found allows concluding that deoxycholic acid is effective in submental fat reduction, causing well-tolerated adverse effects. However, all eligible studies showed a potential industry bias.

Abstract Objective: To assess the influence of the COVID-19 pandemic on levels of anxiety, stress, and orofacial pain in individuals with and without TMD. Material and Methods: In this cross-sectional study, the participants were divided into two groups (n=10, each) experimental group (EG) TMD patients and control group (CG), without TMD. The presence of TMD was confirmed using the RDC/TMD. The Beck Anxiety Scale (BAI), Perceived Stress Scale (PSS), and Oral Analog Scale were used for assessment. The Beck Anxiety Scale is composed of 21 multiple-choice questions describing symptoms of anxiety, while the PSS is a measure that evaluates life situations as stressful. An Oral Analogue Scale was applied to each individual to quantify orofacial pain, with 0 (zero) without pain and 10 (ten) being the worst pain ever felt. The comparison between groups was performed using the Mann-Whitney test. Logistic regression was used to verify TMD dependence in relation to BAI and PSS-10. Quantitative variables were correlated with each other by Pearson's correlation coefficient. The level of significance considered for all tests was 5%. Results: The association was statistically significant (p≤0.05) for BAI and PSS with a TMD. Conclusion: Although the COVID 19 pandemic has had a psychological impact on the general population, patients with TMD have higher levels of anxiety and stress than the control group.

Abstract This editorial addresses the history of Brazilian Oral Research (BOR), official journal of the Brazilian Division of the International Association of Dental Research (SBPqO). BOR is increasingly consolidating itself as the most important journal in Brazilian dental research. However, much still needs to be done. The hard and continuous work to improve the journal will guarantee its permanent growth and result in new achievements for the benefit of the entire dental scientific community.

Abstract This in vitro study evaluated the biocompatibility and abrasivity of whitening and conventional toothpastes. Samples of conventional (non-whitening) - Edel White Infant (EWI) - and whitening toothpastes - Edel White Whitening (EWW), Edel White CAREFORTE (EWC), Colgate Total 12 Ò Professional (C), and Oral-B Whitening (OB) - were dissolved in culture medium (0.2 g sample weight per mL). Human gingival fibroblasts (hGF) were placed in contact with different dilutions of culture media that had been previously exposed to these toothpastes. Cytotoxicity was then assessed using the methyl tetrazolium test (MTT) and the cell survival rate was determined. Genotoxicity was assessed by the micronucleus test (MNT) and the number of micronuclei was determined before and after exposure to the toothpaste solutions. The enamel surface roughness was evaluated in specimens of bovine teeth (n = 10 per group) before and after 10,000 brushing cycles, using the investigated toothpastes. The results were statistically analyzed using the Mann-Whitney U test and two-way ANOVA (p < 0.05). According to the MTT assay, EWW and OB presented significant cytotoxicity (p < 0.01), but no genotoxic (MNT) effects (p > 0.05). C toothpaste was statistically significantly abrasive to the enamel surface (p < 0.01). The findings of this study may be helpful for individualized selection of commercial toothpastes, as some whitening toothpastes present significant cytotoxicity and conventional toothpaste cause significant surface changes.

This study aimed to systematically review the literature to assess the effect of preemptive intravenous ibuprofen on pain reduction after lower third molar surgery. Nine databases (PubMed, Scopus, LILACS, SciELO, Embase, Web of Science, Cochrane, Open Gray, and Open Thesis) were used as sources of research, including “grey literature.” The protocol was registered in PROSPERO. Only randomized clinical trials evaluating the effects of preemptive intravenous ibuprofen on pain during and immediately after the extraction of lower third molars were included, without restrictions of year and language. Two reviewers independently performed the study selection, data extraction, and assessment of the risk of bias. The “Joanna Briggs Institute for Randomized Controlled Trials” tool was used to assess the risk of bias. Each study was categorized according to the percentage of positive responses to the questions corresponding to the assessment instrument. The results were measured narratively/descriptively. The initial search resulted in 3,257 records, of which only three studies (n=150 participants) met the eligibility criteria and were included in the qualitative analysis. All studies were published in 2019. The risk of bias ranged from low to moderate. Two studies found significant pain reduction within 48 h after the procedure. In conclusion, the use of preemptive intravenous ibuprofen for extracting third molars reduces pain and analgesic consumption after the surgical procedure.

Resumo Introdução A Punica granatum L. (PG), utilizada como medicamento fitoterápico, apresenta propriedades terapêuticas, anti-inflamatórias e antioxidante. Embora diversos estudos já tenham sido realizados com este fitoterápico, seus possíveis efeitos citotóxicos nos tecidos humanos ainda não são claros. Objetivo Avaliar a citotoxicidade da PG por meio de cultura celular com duas linhagens: fibroblastos humanos de mucosa oral (FLM) e células de carcinoma epidermoide oral humano (KB). Material e método As células foram submetidas ao teste de viabilidade celular por 24 horas nas concentrações da PG 1%, 0,50%, 0,25%, 0,125%, 0,062% e 0,031%, e aos testes de citotoxicidade celular em 4 horas, 1, 3, 5 e 7 dias, em diferentes concentrações, realizados em triplicata. Foi utilizado um controle negativo (Triton 1%) e um controle positivo sem o extrato de PG. Os dados obtidos foram submetidos à ANOVA (p < 0,05). Resultado Foi possível observar que o extrato da PG possui efeitos inibitórios, apresentando-se maior nas células KB em relação às FLM. Os testes de citotoxicidade e viabilidade mostraram inibição e morte das células KB e FLM nas concentrações 1%, 0,50% e 0,25%. Conclusão O efeito inibitório da PG foi dose-dependentes, mostrando-se maior nas células KB em relação às FLM.

Abstract Introduction Punica granatum L. (PG), used as a herbal medicine, has therapeutic, anti-inflammatory and antioxidant properties, although several studies have already been carried out with this herbal medicine, its possible cytotoxic effects on human tissues are still unclear. Objective To evaluate the cytotoxicity of PG through cell culture with two strains: human oral mucosa fibroblasts (LFM) and human oral squamous cell carcinoma (KB) cells. Material and method The cells were submitted to the cell viability test for 24 hours in the concentrations of PG 1%, 0.50%, 0.25%, 0.125%, 0.062% and 0.031% and the cell cytotoxicity tests in 4 hours, 1, 3, 5 and 7 days in different concentrations, performed in triplicate. A negative control (Triton 1%) and a positive control without the PG extract were used. The data obtained were submitted to ANOVA (p <0.05). Result it was possible to observe that the PG extract has inhibitory effects, being higher in KB cells in relation to LFM. The cytotoxicity and viability tests showed inhibition and death of KB and FLM cells at concentrations of 1%, 0.50% and 0.25%. Conclusion The inhibitory effect of PG was dose dependent, showing itself to be greater in KB cells compared to LMB.

Resumo Introdução As resinas de polimetilmetacrilato e as bisacrílicas são materiais amplamente utilizados para a confecção de restaurações provisórias; no entanto, ambas apresentam uma característica de exotermia durante a polimerização que deve ser investigada por causa de possíveis interferências no sucesso clínico. Objetivo Avaliar a variação de temperatura de polimerização da resina bisacrílica e de uma resina acrílica quimicamente ativada, em preparos classe V, pelo método direto. Material e método Para isso, vinte dentes incisivos inferiores bovinos foram divididos em dois grupos: RA (N=10) com dentes restaurados com resina acrílica e RB (N=10) com dentes restaurados com resina bisacrílica. As mensurações das variações térmicas foram realizadas através de termopares tipo J, ligados a um termômetro óptico, e analisadas por um computador equipado com o software específico. Os dados obtidos foram analisados e submetidos à análise de médias comparadas pelo teste de Tukey (significância de 5%). Resultado Foi possível observar que não houve diferença estatística significante entre ambos os grupos experimentais (p=0,0739), mesmo que aumento de temperatura de RA tenha apresentado média maior (0,52 °C) do que RB (0,44 °C). Conclusão Não existe diferença significativa experimental entre o calor emitido pela resina acrílica e pela resina bisacrílica durante seus processos de polimerização, não definindo a característica de escolha de uma destas para as restaurações provisórias diretas.

Abstract Introduction Polymethyl methacrylate and bis-acryl resins are materials widely used for temporary restorations, however, both have a characteristic of polymerization exotermia that should be investigated because of possible interferences in clinical success. Objective to evaluate the variation of the polymerization temperature of bis-acryl resin and a chemically activated acrylic resin in the temporary restoration by the direct method. Material and method Twenty bovine mandibular incisor teeth were divided into two groups: AR (N = 10) teeth restored with acrylic resin and BR (N = 10) teeth restored with bis-acryl resin. Measurements of thermal variations were performed using type J thermocouples, connected to an optical thermometer and analyzed by a computer equipped with specific software. The obtained data were analyzed and submitted to the analysis of means compared by Tukey test (significance of 5%). Result It was observed that there was no statistically significant difference between both experimental groups (p = 0.0739), even though AR temperature increase presented higher average (0.52ºC) than BR (0.44ºC). Conclusion There is no significant experimental difference between the heat emitted by acrylic resin and bis-acryl resin during their polymerization processes, not defining the factor that characterizes a choice of a material for temporary restorations.

Resumo Objetivo: avaliar o efeito de curto prazo de dois protocolos de desafio erosivo, in vitro, na resistência adesiva de braquetes ortodônticos metálicos em esmalte bovino. Métodos: Sessenta incisivos bovinos foram selecionados e divididos aleatoriamente em seis grupos: SA7 (saliva artificial - 7 dias, Grupo Controle); CC7 (Coca-Cola® - 7 dias); SL7 (suco de limão - 7 dias); SA30 (saliva artificial - 30 dias, Grupo Controle); CC30 (Coca-Cola® - 30 dias); SL30 (suco de limão - 30 dias). Foi realizado o teste de microdureza antes do desafio erosivo, para verificar a padronização das amostras. A imersão foi realizada quatro vezes ao dia, por cinco minutos, durante 7 ou 30 dias. Finalizadas as imersões, os braquetes foram colados e, após 48 horas, foi avaliada a resistência ao cisalhamento. O Índice de Adesivo Remanescente (IAR) também foi avaliado. Para análise dos dados, foram utilizados os testes ANOVA dois fatores, seguido do post-hoc de Tukey e teste t de Student para amostras pareadas, e o teste não-paramétrico de Kruskal-Wallis (α?#8197;= 5%). Resultados: a média e o desvio-padrão do teste de microdureza das amostras totais foi igual a 281,89 ± 44,51 KHN. Não houve diferença estatisticamente significativa na resistência ao cisalhamento para o fator tempo (7 ou 30 dias; F5,54= 0,105; p= 0,901). Contudo, houve diferença estatisticamente significativa para o fator solução (F5,54=6,671; p= 0,003). Essas diferenças ocorreram entre as soluções de Saliva x Coca-Cola® (p= 0,003) e Coca-Cola® x suco de limão (p= 0,029). Ao avaliar o Índice de Adesivo Remanescente, não foi possível verificar diferença significativa entre os grupos. Conclusões: o tempo de imersão utilizado nos protocolos de erosão não afetou a resistência de união dos braquetes aos dentes. A Coca-Cola® induziu valores de resistência ao cisalhamento significativamente mais altos do que o suco de limão e a saliva artificial. No entanto, os efeitos em curto prazo de 7 e 30 dias, nesse estudo in vitro, não podem ser extrapolados para os estudos in vivo. Estudos clínicos devem ser conduzidos, fundamentando os resultados laboratoriais.

Abstract Objective: To assess the short-term effect of two in vitro erosive challenge protocols on the bond strength of metal orthodontic brackets on bovine enamel. Methods: Sixty bovine incisors were selected and randomly divided into six groups: AS7 (artificial saliva - 7 days, Control Group); CC7 (Coca-Cola™ - 7 days); LJ7 (lime juice - 7 days); AS30 (artificial saliva - 30 days, Control Group); CC30 (Coca-Cola™ - 30 days); LJ30 (lime juice - 30 days). Microhardness testing was performed prior to the erosive challenge to verify the standardization of samples. Immersion was performed 4x/day for five minutes, for either 7 or 30 days. After immersions were concluded, the brackets were bonded and shear bond strength was assessed after 48 hours. The Adhesive Remnant Index (ARI) was also assessed. Data were analyzed by two-way ANOVA, followed by Tukey’s post-hoc and Student’s t test for paired samples, and the Kruskal-Wallis non-parametric test (α = 5%). Results: The mean and standard deviation of microhardness testing of total samples were 281.89 ± 44.51 KHN. There was no statistically significant difference in shear bond strength for the time factor (7 or 30 days; F5.54= 0.105; p = 0.901). However, there was a statistically significant difference for the solution factor (F5.54= 6.671; p = 0.003). These differences occurred among solutions of Saliva x Coca-Cola™ (p = 0.003) and Coca-Cola™ x Lime Juice (p= 0.029). The assessment of the Adhesive Remnant Index showed no significant difference between groups. Conclusions: The immersion time used in the erosion protocols did not affect the bond strength of brackets to teeth. Coca-Cola™ induced significantly higher shear bond strength values than lime juice and artificial saliva. However, the short term effects of 7/30 days in this in vitro study may not be extrapolated for in vivo ones. Clinical studies should be conducted, substantiating the laboratory results.

Pacientes em tratamento ortodôntico apresentam restaurações provisórias com frequência. No entanto, poucos estudos avaliam a influência dos adesivos na resistência ao cisalhamento dos bráquetes nessas superfícies. A resina acrílica é comumente indicada para colagem de bráquetes, porém o uso do cianoacrilato como adesivo ortodôntico é uma opção analisada. O objetivo do presente trabalho foi avaliar o desempenho do cianoacrilato associado aos materiais comumente utilizados para a fixação de bráquetes metálicos em restaurações provisórias de resina acrílica. Quarenta amostras em resina acrílica foram preparadas e as superfícies homogeinizadas com lixas de carboneto de silício (320 e 600). Em seguida, as amostras foram divididas aleatoriamente em quatro grupos (n=10) com base no tratamento de superfície e agente de união: G1 - bráquetes colados com resina acrílica; G2 - bráquetes colados com resina acrílica e aplicação de cianoacrilato; G3 - bráquetes colados com Transbond(tm) XT; G4 - bráquetes colados com Transbond(tm) XT e aplicação de cianoacrilato. Foram utilizados bráquetes ortodônticos de aço inoxidável, prescrição Roth, Kirium (3M/Abzil) para incisivos centrais superiores direitos, slot 022. Após colagem, as amostras foram submetidas ao teste de cisalhamento a uma velocidade de 0,5mm/min em uma máquina de ensaios universal (EMIC DL-1000). Os dados foram coletados e submetidos à análise estatística pelo teste ANOVA com nível de significância de 5%. A associação de resina acrílica ao cianoacrilato (G2) resultou na maior resistência ao cisalhamento (13,76 MPa), mas não significativa em comparação aos valores obtidos para a resina acrílica (G1= 7,76 MPa). O mesmo pôde ser observado para a associação Transbond(tm) XT e cianoacrilato (G4= 4,03 MPa) em relação a utilização da Transbond(tm) XT de forma isolada (G3= 3,87 MPa) e resina acrílica. O tratamento de superfície tem efeito significativo na resistência da união dos bráquetes colados aos materiais provisórios. A associação de cianoacrilato ao monômero de metilmetacrilato apresentou maior resistência ao cisalhamento, sendo mais indicada clinicamente.

Patients in orthodontic treatments frequently present composite restorations. However, few studies evaluated the influence of bonding materials within braces shearing bond strength on composite surfaces. The acrylic resin became the recommended material for bonding brackets on these surfaces; however the use of cyanoacrylate emerged as a potential option. The present study aimed to evaluate the performance of cyanoacrylate associated with orthodontic materials commonly used for the fixation of metallic braces on temporary restorations of acrylic resin. Forty samples were prepared with acrylic resin and homogenized with silicon carbide sand paper (320 and 600). The samples were randomly divided in four groups (n=10) based on the material treatment and bonding agent: G1 - braces bonded with acrylic resin; G2 - braces bonded with acrylic resin combined with application of cyanoacrylate; G3 - braces bonded with Transbond(tm) XT; G4 - braces bonded with Transbond(tm) XT combined with application of cyanoacrylate. Only stainless steel braces were used, prescription Roth, Kirium (3M/Abzil) designed for maxillary right central incisors, slot 022. After bonding, the sample underwent shearing tests at 0.5mm/min within a standard testing device (EMIC DL-1000). Statistical data consisted of ANOVA with significance level set at 5%. Group 2 (G2) reached major shearing strength (13.76 MPa). However, it was not statistically significant in face of the outcomes of Group 1 (G1) (G1= 7.76 MPa). The same was observed for the association of Transbond(tm) XT and cyanoacrylate (G4= 4.03MPa) compared with isolated Transbond(tm) XT (G3= 3.87 MPa) and acrylic resin. Surface treatment of orthodontic material revealed a significant effect on shearing strength of temporary materials. The association between cyanoacrylate with monomer of methyl methacrylate presented major shearing strength, becoming more indicated for clinical interventions.

Considerando os valores relativamente pequenos utilizados em odontologia para os ensaios de carregamento verticais axiais, foi desenvolvido um dispositivo de aplicação de carga (DAC) para substituir a máquina de ensaios universal (EMIC). O objetivo deste estudo foi desenvolver um DAC e compará-lo com a EMIC por meio da utilização de carregamentos axiais e não-axiais. Num bloco de poliuretano foi inserido um implante hexágono externo, o qual foi conectado a um pilar protético esteticone. Sobre o pilar protético foi parafusada uma coifa plástica e um pilar cônico foi modelado em resina acrílica, que foi moldada para a obtenção de dez enceramentos iguais que foram fundidos em níquel cromo. Quatro extensômetros foram diametralmente colados ao redor do implante. Cada corpo de prova foi submetido a cargas axiais central (C) e lateral (L) de 30 kgf, em ambos os dispositivos: G1) DAC/C; G2) DAC/L; G3) EMIC/C; G4) EMIC/L. Os dados (µε) foram analisados estatisticamente pelos testes de ANOVA para medidas repetidas e de Tukey (p<0,05). Não houve diferença estatisticamente significante entre os dispositivos DAC e EMIC, independente do tipo de carga. A aplicação de carga não-axial (NA) determinou um aumento significante de tensões ao redor do implante. Foi concluído que o DAC é uma opção confiável, a qual induz microtensão em implantes de forma semelhante à EMIC.

In view of the low loading values commonly employed in dentistry, a load-application device (LAD) was developed as option to the universal testing machine (UTM), using strain gauge analysis. The aim of this study was to develop a load-application device (LAD) and compare the LAD with the UTM apparatus under axial and non-axial loads. An external hexagonal implant was inserted into a polyurethane block and one EsthetiCone abutment was connected to the implant. A plastic prosthetic cylinder was screwed onto the abutment and a conical pattern crown was fabricated using acrylic resin. An impression was made and ten identical standard acrylic resin patterns were obtained from the crown impression, which were cast in nickel-chromium alloy (n=10). Four strain gauges were bonded diametrically around the implant. The specimens were subjected to central (C) and lateral (L) axial loads of 30 kgf, on both devices: G1: LAD/C; G2: LAD/L; G3: UTM/C; G4: UTM/L. The data (με) were statistically analyzed by repeated measures ANOVA and Tukey's test (p<0.05). No statistically significant difference was found between the UTM and LAD devices, regardless of the type of load. It was concluded that the LAD is a reliable alternative, which induces microstrains to implants similar to those obtained with the UTM.

Objectives Evaluate the thickness and the marking quality of different occlusal contact registration strips (OCRS) and a possible correlation between them. Material and Methods The following OCRS were selected: Accufilm II, BK20, BK21, BK22, BK23, BK28, and BK31. The thickness was measured in three points of the OCRS with an electronic measuring device (TESA), and the mean was calculated. To produce the marks on the strips, composite resin specimens were adapted to a universal testing machine (Versat 2000) with 40 kgf load cell at a speed of 1.0 mm/min. The mark images were photographed with a stereoscopic microscope (Stemi SV11) and processed and analyzed by the 550-Leica Qwin® analyzer. Results Values (μm) found in the 1st and 2nd thickness measurements were: Accufilm II - 16.4 and 14.2; BK20 - 10.0 and 8.1; BK21 - 9.5 and 8.0; BK22 - 9.7 and 8.7; BK23 - 9.8 and 7.9; BK28 - 12.8 and 10.0; and BK31 - 8.4 and 8.0, respectively. The mean (mm2) values found in the mark areas were: Accufilm II - 0.078; BK20 - 0.035; BK21 - 0.045; BK22 - 0.012; BK23 - 0.022; BK28 - 0.024; and BK31 - 0.024. The results were submitted to the Kruskal-Wallis (p<0.05) and Pearson’s correlation tests. Conclusions Only in the 2nd measurement, the OCRS thickness observed was similar to the value indicated by the manufacturers; the Accufilm II and the BK28 strips showed the better marks; and no correlation was found between the thickness and the marking area.