Aim To estimate the prevalence and associated factors of self-reported depressive symptoms in undergraduate and graduate dental students. Methods The Depression, Anxiety and Stress Scale (DASS-21) was applied, and only the depression domain was verified. A structured questionnaire was used to collect sociodemographic, behavioral, and COVID-19 pandemic-related fear variables. Academic performance was assessed based on academic records, ranging from 0 (worst possible grade) to 10 (best possible grade). Respondents included 408 regularly enrolled dental students. Bi- and multivariate analyses were performed using Poisson regression with robust variance to verify the association between at least moderate depressive symptoms and independent variables. Results The prevalence of at least moderate depression was 40.5% among undergraduate students and 26% among graduate students. The prevalence of fear and anxiety due to the COVID-19 pandemic was 96.1% among undergraduate students and 93.5% among graduate students. In the final multivariate analysis, being female (prevalence ratio [PR]:2.01; 95% confidence interval [95%CI]:1.36–2.96) was associated with a higher PR for depression. Conversely, no exposure to smoking (PR:0.54; 95%CI:0.36–0.82) and a final academic performance average ≥7.0 (PR:0.56; 95%CI:0.41–0.76) was associated with a lower PR for depression. Finally, among graduate students, a non-heterosexual orientation was associated with a higher PR for depression (PR:6.70; 95%CI:2.21–20.29). Conclusion Higher rates of depression symptoms were observed in female undergraduates, students with lower academic performance and smoking exposure, and graduate dental students with a non-heterosexual orientation.

Abstract The aim of this study was to explore associated variables with sense of coherence (SOC), and dental environment stress (DES) in a sample of dental students. All undergraduate (n = 474) and graduate (n = 105) dental students enrolled in the first semester of 2020 at a public university in southern Brazil were invited to participate. Data collection was performed by an online questionnaire, which included information related to sociodemographic and educational characteristics, biopsychosocial factors, aspects related to feelings experienced in the COVID-19 pandemic, and the SOC scale. The study outcome (DES) was measured by a validated tool. Linear regression analyses were performed to identify the associations between the outcome and all independent variables. A total of 408 students were included (response rate: 70.5%). The overall mean score of the DES scale was 73.95 (SD: 24.13). Students with higher SOC scores were observed to have significantly lower DES scores (βGRADUATE: -0.376; 95%: -0.482 to -0.271; βUNDERGRADUATE: -0.478; 95%:-0.658 to -0.297). Female undergraduate students (β: 11.788; 95%CI: 7.161–16.415) had higher DES scores compared with undergraduate male students. In addition, the presence of anxiety symptoms when providing dental care to patients with symptoms or suspected COVID-19 infection was associated with higher DES scores (β: 10.460; 95%CI: 5.644–15.277) among undergraduate dental students. The level of stress was higher in non-white undergraduate students than white (β: 8.912; 95%CI: 3.581–14.244). Among both undergraduate and graduate dental students, higher SOC scores were associated with lower DES. SOC, , (SOC) (DES n 474 105 202 participate questionnaire characteristics factors COVID19 COVID 19 COVID-1 pandemic tool 40 response rate 70.5%. 705 70.5% . 70 5 70.5%) 7395 73 95 73.9 SD (SD 24.13. 2413 24.13 24 13 24.13) βGRADUATE (βGRADUATE 0.376 0376 0 376 -0.376 95% 0.482 0482 482 -0.48 0.271 0271 271 -0.271 βUNDERGRADUATE 0.478 0478 478 -0.478 95%0.658 950658 0.658 658 95%:-0.65 0.297. 0297 0.297 297 -0.297) β (β 11.788 11788 11 788 95%CI 95CI CI 7.161–16.415 716116415 7 161 16 415 addition 10.460 10460 10 460 5.644–15.277 564415277 644 15 277 nonwhite non 8.912 8912 8 912 3.581–14.244. 358114244 3.581–14.244 3 581 14 244 3.581–14.244) (SOC 47 20 COVID1 1 COVID- 4 70.5 739 9 73. 241 24.1 2 0.37 037 37 -0.37 0.48 048 48 -0.4 0.27 027 27 -0.27 0.47 047 -0.47 95%0.65 95065 0658 0.65 65 95%:-0.6 029 0.29 29 -0.297 11.78 1178 78 7.161–16.41 71611641 41 10.46 1046 46 5.644–15.27 56441527 64 8.91 891 91 35811424 3.581–14.24 58 70. 24. 0.3 03 -0.3 0.4 04 -0. 0.2 02 -0.2 95%0.6 9506 065 0.6 6 95%:-0. -0.29 11.7 117 7.161–16.4 7161164 10.4 104 5.644–15.2 5644152 8.9 89 3581142 3.581–14.2 0. -0 95%0. 950 06 95%:-0 11. 7.161–16. 716116 10. 5.644–15. 564415 8. 358114 3.581–14. - 95%0 95%:- 7.161–16 71611 5.644–15 56441 35811 3.581–14 7.161–1 7161 5.644–1 5644 3581 3.581–1 7.161– 716 5.644– 564 358 3.581– 7.161 71 5.644 56 35 3.581 7.16 5.64 3.58 7.1 5.6 3.5 7. 5. 3.

Resumo A periodontite e a hipertensão arterial são duas das patologias com maior prevalência global, as evidências relatadas até o momento têm sido favoráveis a uma associação entre elas. Este estudo transversal teve como objetivo avaliar e comparar contagem microbiológicas de pacientes hipertensos e normotensos com periodontite. Dados sociodemográficos, comportamentais, de saúde sistêmica e parâmetros clínicos periodontais foram avaliados. Contagens de A. actinomycetemcomitans, P. intermedia, P. gingivalis e F. nucleatum foram realizadas por reação em cadeia da polimerase em tempo real utilizando amostras de biofilme subgengival. Trinta e oito pacientes foram incluídos nesta análise preliminar, divididos em dois grupos: Grupo Normotenso (GN) (n = 14) e Grupo Hipertenso (GH) (n = 24). Pacientes diagnosticados com periodontite compuseram os dois grupos. A análise dos dados foi realizada com nível de significância de 5%. Não houve diferença significativa entre os grupos para o diagnóstico clínico de periodontite. Além disso, os hipertensos apresentaram maior contagem de P. intermedia, P. gingivalis e F. nucleatum quando comparados aos normotensos. Os parâmetros profundidade de sondagem, sangramento à sondagem e contagem de A. actinomycetemcomitans não apresentaram diferenças estatísticas entre os grupos. Com esses resultados preliminares, pode-se concluir que a presença de hipertensão arterial pode estar associada a uma maior quantidade de bactérias periodontopatogênicas de algumas espécies em indivíduos com periodontite.

Abstract Periodontitis and arterial hypertension are two of the pathologies with the highest global prevalence; evidence reported so far has been favorable to an association between them. This cross-sectional study aimed to evaluate and compare the microbiological counts of hypertensive and normotensive patients with periodontitis. Sociodemographic, behavioral, systemic health data and periodontal clinical parameters were assessed. Counts of A. actinomycetemcomitans, P. intermedia, P. gingivalis and F. nucleatum were performed by real-time polymerase chain reaction using subgingival biofilm samples. Thirty-eight patients were included in this preliminary analysis, divided into two groups: Normotensive Group (NG) (n = 14) and Hypertensive Group (HG) (n = 24). Patients diagnosed with periodontitis composed both groups. Data analysis was performed with significance level of 5%. There was no significant difference between groups for clinical periodontitis diagnosis. In addition, hypertensive individuals had higher P. intermedia, P. gingivalis, and F. nucleatum counts when compared to normotensive individuals. The parameters probing pocket depth, bleeding on probing, and A. actinomycetemcomitans count did not presented statistical differences between groups. With these preliminary results, it can be concluded that the presence of arterial hypertension may be associated with a greater quantity of periodontopathogenic bacterial of some species in individuals with periodontitis.

RESUMO Objetivo: Avaliar clinicamente o efeito do debridamento ultrassônico de boca toda no tratamento da periodontite crônica severa em pacientes diabéticos. Métodos: Dezesseis pacientes diabéticos descompensados (Hemoglobina Glicada ≥ 7%) com periodontite crônica severa (mínimo de 8 dentes com profundidade de sondagem ≥ 5 mm e sangramento à sondagem) separados aleatoriamente em 2 grupos: Controle (7): raspagem e alisamento radicular por quadrante e Teste (9): debridamento ultrassônico sessão única de 45 minutos. Os parâmetros clínicos avaliados foram: Índice de placa, Índice gengival, Sangramento à Sondagem, Profundidade de Sondagem, Nível de inserção clínico e Posição da Margem Gengival. As variáveis foram avaliadas no início, 1 e 3 meses após o tratamento. Para análise das variáveis quantitativas (Profundidade de sondagem, Nível de inserção e Posição da margem gengival de bolsas moderadas) foram realizados ANOVA e teste de Tukey e para as demais foram utilizados os testes de Friedman e Mann-Whitney. Resultados: Observou-se melhora na profundidade de sondagem e nível de inserção clínica após o tratamento em ambos os grupos, sem diferenças estatisticamente significativas entre eles. Após 3 meses, nas bolsas inicialmente profundas, a profundidade de sondagem reduziu 1,6 e 1,7 mm nos grupos teste e controle, respectivamente. Houve um ganho estatisticamente significante no nível de inserção ≥ 2 mm nos grupos controle (10,1%) e teste (13,4%), aos 3 meses. Conclusão: O debridamento ultrassônico de boca toda promoveu resultados clínicos semelhantes aos obtidos com a raspagem e alisamento radicular no tratamento da periodontite crônica severa em indivíduos diabéticos.

ABSTRACT Objective: The purpose of this study was to clinically evaluate the effect of one-stage full-mouth ultrasonic debridement in the treatment of diabetic subjects with severe chronic periodontitis. Methods: Sixteen patients with uncontrolled diabetes (glycated hemoglobin ≥ 7%) and severe chronic periodontitis (at least 8 teeth with a probing depth and bleeding on probing were selected and randomly assigned to 2 treatment groups: control group (n=7) - quadrant-wise scaling and root planning; test group (n=9) - full-mouth ultrasonic debridement in one session of 45 minutes. The following outcomes were assessed: plaque index, gingival index, bleeding on probing, probing depth, clinical attachment level and gingival margin position. All parameters were assessed at baseline, 1 and 3 months after treatment. Probing depth, clinical attachment level and gingival margin position were analyzed using ANOVA and Tukey test, and the other clinical parameters analysed with the Friedman and Mann-Whitney tests. Results: An improvement in probing depth, clinical attachment level was observed after treatment in both groups, but without statistically significant differences between them. After 3 months, in initially deep pockets, the PD decreased 1.6 mm and 1.7 mm in test and control group, respectively. Clinical attachment level gain ≥ 2 mm was statistically significant at sites in control (10.1%) and test (13,4%) groups in 3 months. Conclusions: One-stage full-mouth ultrasonic debridement promoted similar clinical outcomes to those obtained with the scaling and root planning in the treatment of diabetic subjects with severe chronic periodontitis.

Abstract: The understanding of the biological mechanisms involved in root resorption in deciduous teeth is important to the future development of preventive measures and treatments of this condition. The aim of the present study was to compare the expression and immunostaining of iNOS, MMP-9, OPG and RANKL in the periodontal ligament (PDL) of deciduous teeth with physiologic root resorption (GI), inflammatory pathological root resorption (GII) and permanent teeth (GIII), the negative control. Teeth in GI (n = 10), GII (n = 10) and (GIII) (n = 10) were submitted to immunohistochemical analysis to determine the expression of iNOS, MMP-9, OPG, and RANKL. The immunostaining was analysed by optical density. Statistical analysis included one-way ANOVA, followed by Student-Newman-Keuls post hoc test (p < 0.05). The results showed that iNOS, MMP-9 and RANKL expression in the PDL was higher in GII compared to GI and GIII (p < 0.05). Moreover, RANKL expression was higher in GI compared to GIII (p < 0.001), while OPG immunolabelling was lower in GII compared to GI and GIII (p < 0.001). The PDL of deciduous teeth bearing inflammatory processed exhibited upregulation of resorption-associated factors as well as enzymes related to tissue degradation which, in turn explains the exacerbation and greater susceptibility of those teeth to root resorption process.

Resumo Esse estudo objetivou avaliar a prevalência de perda dentária e fatores associados em adolescentes institucionalizados. Esse estudo transversal incluiu 68 adolescentes do sexo masculino de um Centro de Atendimento Socioeducativo (CASE) com idades entre 15 e 19 anos. Questionários estruturados foram aplicados individualmente para acessar variáveis sociodemográficas, econômicas, médicas, comportamentais e autopercepção de saúde bucal. Todos os dentes presentes foram avaliados pelo Índice de dentes Cariados, Perdidos e Obturados (CPOD). A prevalência de perda dentária foi analisada em indivíduos com ≥1 dente perdido. Associações entre perda dentária e variáveis de exposição foram analisadas por regressão de Poisson com estimativa de variância robusta. A prevalência de perda dentária foi 47,06%. Primeiros molares na mandíbula e maxila e incisivos centrais na maxila foram os dentes mais ausentes. No modelo multivariado, número de dentes cariados esteve associado com perda dentária, e aqueles que faziam uso diário de medicações foram associados a maior perda dentária. Além disso, perda dentária foi associada com cárie dentária e uso diário de medicação. Promoção de saúde bucal e seu tratamento devem ser implementados nessas instituições para reduzir a prevalência de perda dentária nesses adolescentes.

Abstract This study aimed to assess the prevalence of tooth loss and associated factors in institutionalized adolescents. This cross-sectional study included 68 male adolescents incarcerated from Socio-Educational Assistance Center (CASE) aged between 15 and 19 years. Questionnaires were applied individually to assess sociodemographical, economical, medical, behavioral and oral health self-perception variables. All present teeth were evaluated by Decay, Missing, Filling (DMF) Index. The prevalence of tooth loss was analyzed in individuals with ≥1 tooth loss. Associations between tooth loss and exposure variables studied were analyzed by Poisson Regression with robust variance estimation. The prevalence of tooth loss was 47.06%. First molars in the mandible and maxilla and central incisor in the maxilla were the most absent teeth. In the multivariate model, number of decayed teeth, and those that reported daily use of medication were associated with higher tooth loss. Besides, tooth loss was associated with decayed tooth and daily use of medication. Oral health promotion and treatment should be implemented in these institutions to reduce the prevalence of dental loss in these adolescents.

RESUMO Este estudo transversal foi realizado por meio de um questionário online. O questionário foi aplicado a endodontistas e coletou informagoes sobre modificagoes práticas durante o tratamento endodontico para combater o surto de COVID-19 e proteger profissionais e pacientes. Um total de 1105 participantes do Brasil participaram da pesquisa. Mais de 90% dos entrevistados identificam o alto risco de infecgao por COVID-19 para os dentistas e a necessidade de mudar algumas práticas clínicas. A maioria dos entrevistados (60,1%) segue parcialmente o isolamento social. A necessidade de mudangas dos Equipamentos de Protegao Individual (EPIs) durante as consultas odontológicas foi referida por 97,1% dos entrevistados. O uso de EPIs mínimos adequados durante o período pandémico foi associado á área de residencia e ao estado civil dos participantes. Apenas 30% dos participantes afirmou usar os EPIs mínimos durante a pandemia. A maioria dos entrevistados mudará a preparagao do acesso á cavidade para reduzir a disseminagao do virus. Outras mudangas nas consultas endodonticas foram descritas na pesquisa: maior atengao ás medidas de biosseguranga, duragao das consultas odontológicas e intervalos entre as consultas. Os endodontistas ainda precisam distinguir a melhor maneira para realizar seus procedimentos com seguranga, durante a pandemia de COVID-19. Diretrizes específicas requerem informagoes detalhadas para cada especialidade e seus procedimentos.

ABSTRACT This study evaluated the impact of COVID-19 on the endodontic treatment routine. It was a cross-sectional study using an online questionnaire applied to endodontists to collect information about practical modifications during endodontic treatment to protect professionals and patients against the COVID-19 outbreak. A total 1105 participants from Brazil participated in the survey. More than 90% of respondents identify the high risk of COVID-19 infection to dentists and the need to change some clinical practices. Most respondents (60.1%) are partially following social isolation. The need for a change in Personal Protective Equipment (PPE) during dental appointments was mentioned by 97.1% of respondents. The use of minimal adequate PPE during the pandemic period was associated with the area of residence and marital status of participants. Only 30% of respondents say they use the minimal adequate PPE. Most respondents will change cavity access preparation to reduce virus dissemination. Other changes in endodontic appointments were described in the survey: greater attention to biosafety measures, duration of dental appointments, and duration of intervals between appointments. Endodontists still need to identify the best arrangement for performing their procedures safely during the COVID-19 pandemic. Specific guidelines require detailed information for each specialty and its procedures.

Resumo Esse estudo objetivou avaliar a prevalência de perda dentária e fatores associados em adolescentes institucionalizados. Esse estudo transversal incluiu 68 adolescentes do sexo masculino de um Centro de Atendimento Socioeducativo (CASE) com idades entre 15 e 19 anos. Questionários estruturados foram aplicados individualmente para acessar variáveis sociodemográficas, econômicas, médicas, comportamentais e autopercepção de saúde bucal. Todos os dentes presentes foram avaliados pelo Índice de dentes Cariados, Perdidos e Obturados (CPOD). A prevalência de perda dentária foi analisada em indivíduos com ≥1 dente perdido. Associações entre perda dentária e variáveis de exposição foram analisadas por regressão de Poisson com estimativa de variância robusta. A prevalência de perda dentária foi 47,06%. Primeiros molares na mandíbula e maxila e incisivos centrais na maxila foram os dentes mais ausentes. No modelo multivariado, número de dentes cariados esteve associado com perda dentária, e aqueles que faziam uso diário de medicações foram associados a maior perda dentária. Além disso, perda dentária foi associada com cárie dentária e uso diário de medicação. Promoção de saúde bucal e seu tratamento devem ser implementados nessas instituições para reduzir a prevalência de perda dentária nesses adolescentes.

Abstract This study aimed to assess the prevalence of tooth loss and associated factors in institutionalized adolescents. This cross-sectional study included 68 male adolescents incarcerated from Socio-Educational Assistance Center (CASE) aged between 15 and 19 years. Questionnaires were applied individually to assess sociodemographical, economical, medical, behavioral and oral health self-perception variables. All present teeth were evaluated by Decay, Missing, Filling (DMF) Index. The prevalence of tooth loss was analyzed in individuals with ≥1 tooth loss. Associations between tooth loss and exposure variables studied were analyzed by Poisson Regression with robust variance estimation. The prevalence of tooth loss was 47.06%. First molars in the mandible and maxilla and central incisor in the maxilla were the most absent teeth. In the multivariate model, number of decayed teeth, and those that reported daily use of medication were associated with higher tooth loss. Besides, tooth loss was associated with decayed tooth and daily use of medication. Oral health promotion and treatment should be implemented in these institutions to reduce the prevalence of dental loss in these adolescents.

ABSTRACT OBJECTIVE To describe the sampling strategy of an epidemiological survey with the aid of satellite images, including details of the multistage probability sampling process. METHODS A probability sample of individuals living in the rural area of Rosário do Sul, state of Rio Grande do Sul, Brazil, aged 15 years old or more, was evaluated. Participants answered questionnaires (medical history, sociodemographic characteristics, habits, alcohol use, quality of life, stress, rumination, and self-perceived periodontal diseases), and were subjected to clinical oral examinations as well as anthropometric measurements (blood pressure, height, weight, abdominal and waist circumferences). Oral evaluation comprehended a complete periodontal exam at six sites per tooth, including the following assessments: furcation involvement; dental abrasion; tooth decay, including the indexing of missing and filled surfaces; O’Brien index; gingival abrasion; oral cavity and lip lesions; complete periapical radiographic exam, and use of prostheses. Besides this oral clinical approach, subgingival plaque, crevicular gingival fluid, saliva, and blood samples were collected. Examiners were trained and calibrated during previous evaluations. A pilot study allowed the logistic of the performed exams to be adjusted as needed. RESULTS Among 1,087 eligible individuals, 688 were examined (63.3%). Age, sex, and skin color data were compared to data from the last demographic census (2010) of the Brazilian Institute of Geography and Statistics, which served to validate the sampling strategy. CONCLUSIONS The careful methods used in this study, in which satellite images were used in the delimitation of epidemiological areas, ensure the quality of the estimates obtained and allow for these estimates to be used in oral health surveillance and health policies improvements.

ABSTRACT OBJECTIVE To describe the sampling strategy of an epidemiological survey with the aid of satellite images, including details of the multistage probability sampling process. METHODS A probability sample of individuals living in the rural area of Rosário do Sul, state of Rio Grande do Sul, Brazil, aged 15 years old or more, was evaluated. Participants answered questionnaires (medical history, sociodemographic characteristics, habits, alcohol use, quality of life, stress, rumination, and self-perceived periodontal diseases), and were subjected to clinical oral examinations as well as anthropometric measurements (blood pressure, height, weight, abdominal and waist circumferences). Oral evaluation comprehended a complete periodontal exam at six sites per tooth, including the following assessments: furcation involvement; dental abrasion; tooth decay, including the indexing of missing and filled surfaces; O’Brien index; gingival abrasion; oral cavity and lip lesions; complete periapical radiographic exam, and use of prostheses. Besides this oral clinical approach, subgingival plaque, crevicular gingival fluid, saliva, and blood samples were collected. Examiners were trained and calibrated during previous evaluations. A pilot study allowed the logistic of the performed exams to be adjusted as needed. RESULTS Among 1,087 eligible individuals, 688 were examined (63.3%). Age, sex, and skin color data were compared to data from the last demographic census (2010) of the Brazilian Institute of Geography and Statistics, which served to validate the sampling strategy. CONCLUSIONS The careful methods used in this study, in which satellite images were used in the delimitation of epidemiological areas, ensure the quality of the estimates obtained and allow for these estimates to be used in oral health surveillance and health policies improvements.

Abstract Laboratory evidence has demonstrated the antimicrobial effect of Melaleuca alternifolia (MEL) against oral microorganisms. This randomized, double-blind, crossover clinical trial, compared the anti-biofilm and anti-inflammatory effects of MEL nanoparticles with 0.12% chlorhexidine gluconate (CHX) on biofilm-free (BF) and biofilm-covered (BC) surfaces. Before each experimental period, the participants refrained from all oral hygiene practices for 72 hours. The 60 participants were randomly assigned to professional prophylaxis in two quadrants (Q1–Q3 or Q2–Q4), and rinsed with MEL or CHX for four days. The Quigley & Hein plaque index (QHPI), gingival crevicular fluid (GCF) volume, and participants’ perceptions were assessed. CHX showed significantly lower mean QHPI on BF (2.65 ± 0.34 vs. 3.34 ± 0.33, p < 0.05) and BC surfaces (2.84 ± 0.37 vs. 3.37 ± 0.33, p < 0.05). Intragroup comparisons indicated reductions in GCF in all the groups, with significant differences only for CHX on BF surfaces (p < 0.05). Intergroup comparisons revealed no significant differences (p > 0.05). Based on individual perceptions, CHX had better taste and biofilm control, but resulted in a greater change in taste. Nevertheless, MEL demonstrated anti-inflammatory effects similar to those of CHX. Further clinical trials testing different protocols, concentrations and follow-up periods are required to establish its clinical application.

Abstract Crack cocaine use appears to have an impact on oral conditions. However, changes in the salivary flow among crack users have not been fully clarified. The aim of this study was to compare stimulated salivary flow and the occurrence of hyposalivation between crack users and non-users. A cross-sectional study was conducted involving 40 crack users and 40 controls matched for sex, age, and smoking habits. Interviews were conducted to acquire data on the perception of dry mouth (xerostomia) and drug use. Stimulated salivary flow was determined using the spitting method. A significant reduction in stimulated salivary flow was found among crack users in comparison to non-users (1.02 vs. 1.59 ml/min). A total of 42.5% and 15% of crack users had very low and low stimulated salivary flow, respectively. Moreover, 65% of users reported xerostomia in comparison to 37.5% non-users (p < 0.012). No significant association was found between xerostomia and hyposalivation (p = 0.384). A multivariate analysis revealed that individuals older than 26 years of age, those with a low household income, and crack users (prevalence ratio: 2.59) had a significant association with the occurrence of hyposalivation. A significant association was found between the use of crack and reduced salivary flow. The use of crack was associated with the occurrence of hyposalivation in the multivariate analysis.

Resumo Objetivo Comparar a eficácia antimicrobiana de clorexidina 0,12% (CHX) e solução de chá verde (CV) (Camellia sinensis) em biofilmes formados em diferentes tensões de oxigênio em um modelo in situ. Método Vinte e cinco estudantes de odontologia foram elegíveis. Um dispositivo com espécimes de esmalte (EE) padronizados, voltado para o palato e para vestibular foram inseridos nos voluntários por 7 dias. Durante os primeiros quatro dias nenhum agente foi aplicado. A partir do quinto dia, ambos os agentes foram aplicados nos EEs no grupo teste e nenhum agente foi aplicado no grupo EE controle. Após 7 dias, os fragmentos EEs foram removidos dos dispositivos, sonicados, plaqueados em ágar, e incubado durante 24 h a 37 °C para determinar unidades formadoras de colonias (UFCs). Resultado CHX teve significativamente melhor eficácia em comparação com CV nos EEs para vestibular (1.330 vs. 2.170 UFC/mL) e EEs voltados para o palatal (2.250 vs. 2.520 UFC/mL). Comparações intragrupos mostraram maior eficácia em EEs vestibulares do que as EEs voltadas para o palato (1.330 vs. 2.250 UFC/mL para CHX e 2170 vs, 2520 UFC/mL para CV) em ambas as soluções. Análise dos controles, mostrou a formação de biofilme significativamente maior em comparação com EEs palatinas e bucais. Conclusão CHX tem uma eficácia maior do que o chá verde em biofilmes formados por 4 dias. A eficácia dos agentes foi reduzida para os biofilmes em ambiente com baixa tensão de oxigênio. A tensão de oxigênio parece influenciar na eficácia dos agentes testados.

Abstract Objective To compare the antimicrobial efficacy of a 0.12% chlorhexidine (CHX) and herbal green tea (Camellia sinensis) solution on established biofilms formed at different oxygen tensions in an in situ model. Method Twenty-five dental students were eligible for the study. In situ devices with standardized enamel specimens (ES) facing the palatal and buccal sides were inserted in the mouths of volunteers for a 7 day period. No agent was applied during the first four days. From the fifth day onward, both agents were applied to the test ES group and no agent was applied to the control ES group. After 7 days the ES fragments were removed from the devices, sonicated, plated on agar, and incubated for 24 h at 37 °C to determine and quantify the colony forming units (CFUs). Result CHX had significantly higher efficacy compared to green tea on the buccal (1330 vs. 2170 CFU/µL) and palatal (2250 vs. 2520 CFU/µL) ES. In addition, intragroup comparisons showed significantly higher efficacy in buccal ES over palatal ES (1330 vs. 2250 CFU/µL for CHX and 2170 vs, 2520 CFU/µL for CV) for both solutions. Analysis of the ES controls showed significantly higher biofilm formation in palatal ES compared to buccal ES. Conclusion CHX has higher efficacy than green tea on 4-day biofilms. The efficacy of both agents was reduced for biofilms grown in a low oxygen tension environment. Therefore, the oxygen tension environment seems to influence the efficacy of the tested agents.

TEMA: características dos sons fricativos surdos. OBJETIVO: propor uma revisão da literatura pertinente às características acústicas, fonéticas e fonológicas dos fonemas fricativos surdos que integram o sistema fonológico do Português. Além disso, são descritas suas aplicações na terapia vocal. CONCLUSÕES: os fricativos são fonemas agudos, abrangendo de 2500 a 8000Hz; são plenamente adquiridos até os 3:7 anos de idade; o /s/ que também é o mais afetado em casos de frênulo lingual curto; a omissão do /s/ é uma das ocorrências mais freqüentes na alfabetização; sendo que, no desvio fonológico e na fissura lábio-palatina, freqüentemente ocorre comprometimento de toda a classe de fricativos. Na avaliação de voz, os fricativos são mencionados com as medidas de TMF e relação s/z, bem como seu uso como sons de apoio na fonoterapia.

BACKGROUND: characteristics of voiceless fricative sounds PURPOSE: to review the literature related to acoustic, phonetics and phonological characteristics of voiceless fricative sounds that are part of the phonological system of the Portuguese Language. Furthermore, it describes the use of these sounds in voice therapy. CONCLUSIONS: fricatives are acute phonemes comprised between 2500 and 8000 Hz; they are fully acquired up to the age of 3:7 years; the /s/, which is the most affected in cases of short lingual frenum; omission of the /s/ is one of the most frequent occurrences during literacy education; and in the phonological deviation and labial-palatine fissure the entire class of fricatives is frequently affected. In voice assessment, fricative sounds are mentioned as TMF measurements and s/z relationship, and their use as support sounds in speech therapy.