Abstract Evaluate the shaping ability and preparation time using a pediatric motor-driven rotary instrumentation compared to other systems in resin prototypes of primary molars. Methods: Thirty specimens were scanned in micro-CT and divided into three groups according to the instrumentation type: pediatric motor-driven Sequence baby File (SBF); conventional motor-driven (Sequence Rotary File - SRF); manual K file. Instrumentation time was timed. After preparation, the specimens were scanned again. The pre- and post-instrumentation images were superimposed to measure the amount of root canal deviation and the resin remnant thickness. ANOVA followed by the Tukey test analyzed the comparisons between groups (p<0.05). Results: No statistically significant differences occurred in root canal deviation among groups (p>0.05). There were statistically significant differences in the comparison among root thirds (p<0.001) but without significant differences in the interaction group vs. root third (p>0.05). Both motor-driven instrumentations showed statistically greater weariness than manual instrumentation (p<0.001), without significant significant differences between SBF and SRF. Motor-driven instrumentation had a shorter working time than manual instrumentation (p<0.001). Conclusion: Pediatric motor-driven instrumentation demonstrated good outcomes in relation to root canal deviation and amount of remnant structure, with shorter instrumentation time. SBF can be a suitable alternative for endodontic instrumentation in primary molars.

Resumo Objetivo: Avaliar os resultados da instrumentação endodôntica e o tempo de preparo de lima odontopediátrica ativada por motor (Sequence Baby File- SBF) em canais de molares decíduos prototipados. Métodos: Trinta espécimes foram escaneados em micro-CT e divididos em três grupos de acordo com o tipo de instrumentação: mecanizada odontopediátrica (SBF); mecanizada convencional; lima K manual. O tempo de instrumentação foi cronometrado. Após o preparo, os espécimes foram escaneados novamente. As imagens pré e pós-instrumentação foram sobrepostas e a quantidade de desvio do canal radicular e a espessura de resina remanescente foram mensurados. Para as análises de comparações entre os grupos foram realizados teste ANOVA seguido do teste de Tukey (p<0,05). Resultados: Não ocorreram diferenças estatisticamente significativas entre os grupos no desvio do canal radicular (p>0,05). Houve diferenças estatisticamente significativas na comparação entre terços radiculares (p<0,001), mas sem diferenças significativas na interação grupo vs. terço radicular (p>0,05). A instrumentação mecanizada apresentou desgaste estatisticamente maior do que a instrumentação manual (p<0,001), sem diferenças estatísticas entre a SBF e a lima mecanizada convencional. A instrumentação mecanizada teve menor tempo de trabalho quando comparado a instrumentação manual (p<0,001). Conclusão: A instrumentação mecanizada odontopediátrica demonstrou bons resultados em relação ao desvio do canal radicular e quantidade de estrutura remanescente, com menor tempo de instrumentação. A SBF pode ser uma alternativa adequada para a instrumentação endodôntica em molares decíduos.

Abstract This study aimed to evaluate the influence of cleft width on dental arch symmetry of children with unilateral cleft lip and palate. Forty-one children were subjected to impression preoperatively (T1; mean age = 0.31 ± 0.07 years) and postoperatively (T2; mean age = 6 .73 ± 1.02 years). Eighty-two digitized dental casts were analyzed by stereophotogrammetry software. The cleft palate width was measured in the anterior (P-P’), middle (M-M’), and posterior (U-U’) regions. Also, the following measurements were obtained: anterior intersegment (I-C’) and intrasegment (I-C); total intersegment (I-T’) and intrasegment (I-T); cleft-side (C’-T’) and non-cleft-side (C-T) canine tuberosity. Paired t test and Pearson correlation coefficient were applied (α = 5%). Cleft width had the following means: 10.16 (± 3.46) mm for P-P’, 12.45 (± 3.00) mm for M-M’, and 12.57 (± 2.71) mm for U-U’. In the longitudinal analysis, I-C’ had a significant reduction, while the other measurements significantly increased (p < 0.001). Asymmetry was verified in the following analyses at T1: I-C’ vs. I-C and I-T’ vs. I-T (p < 0.001); at T2, only in I-C’ vs. I-C (p < 0.001). At T1, P-P’ vs. I-C’ (r = 0.722 and p < 0.001), P-P’ vs. I-T’ (r = 0.593 and p < 0.001), M-M’ vs. I-C’ (r = 0.620 and p < 0.001), and M-M’ vs. I-T’ (r = 0.327 and p < 0.05) showed a positive and significant correlation. At T2, there was a correlation between M-M’ and I-C’ (r = 0.377 and p < 0.05). In conclusion, the anterior and middle cleft widths influenced palatal asymmetry in the first months of life, while middle width influenced residual asymmetry.

Abstract To assess facial changes after oral rehabilitation with complete dentures (CDs) by 3D technology allows understanding the results of a treatment that changes facial proportions. Precise outcome parameters can improve decision making. Objective This descriptive observational research aimed to assess facial changes in completely edentulous patients after oral rehabilitation with a CD by a 3D stereophotogrammetry system. Methodology 30 edentulous patients (7 men and 23 women), aged 50 to 75, were analyzed with stereophotogrammetry at 28 previously determined anthropometric landmarks, at 2 different times: T1, before treatment, and T2, after inserting the CDs. Images were analyzed with a specific software for linear and angular measurements. The paired t-test was used to compare timestamps (α=0.05). Results Major changes were observed in 7 of the 13 linear measures and 7 of the 9 angular measures. The following linear measurements had an increase: Sn-Gn (lower third of the face), Ls-Li (height of the vermilion lip), and ChL-ChR (mouth width). Sn-Ls (nasal philtrum height) decreased. For angular measurements, Sn-St-Pg (lower facial convexity) angles increased, and the Prn-Sn-Ls (nasolabial angle) and GoR-Pg-GoL (mandible convexity) angles decreased. Conclusions Major facial changes in newly rehabilitated edentulous patients with CDs included an increase of the lower third of the face, of the vermilion lip, of mouth width, and of the lower facial convexity, and a decrease of the nasolabial angle and mandible convexity.

Abstract Rotational instrumentation is an alternative for the clinical practice of pediatric dentists. However, there are few records in the literature on the clinical and radiographic aspects of treated teeth over time. Objectives: Compare instrumentation time and filling quality between manual (k-file) and rotary (Hyflex EDM®) files, and clinically and radiographically follow-up the treated teeth for 12 months. Moreover, the characteristics of glass ionomer restorations and their interference in the treatment prognosis over time were evaluated. Methodology: In total, 40 children with pulp involvement in primary molars received treatment with Hyflex EDM® or manual rotary files, performed by an operator. Clinical and radiographic aspects were observed at different times to determine the effectiveness of each technique. Results: The rotary system reduced instrumentation time when compared to the use of manual files (p≤0.05), but there was no difference in filling quality between the groups (p≥0.05). Moreover, both types of instrumentation were effective for 12 months (p≥0.05), and restoration retention influenced the emergence of periapical lesions (p≤0.05). Conclusion: Although rotary files reduce clinical time, the clinical and radiographic aspects of both techniques were similar over 12 months. Moreover, restoration retention has been shown to be related to treatment prognosis.

Abstract Oral cleft surgical repairs are performed using different techniques worldwide. Objective To evaluate and compare the development of the dental arches of children with unilateral cleft lip and palate before and after the primary surgeries performed with different techniques at the first months and six years of life. Methodology This is a retrospective longitudinal study. The sample comprised 56 dental casts divided int the following groups: Group 1 (G1) – cheiloplasty (Millard technique) at three months and one-step palatoplasty (von Langenbeck technique) at 12 months; and Group 2 (G2) – cheiloplasty (Millard technique) and two-step palatoplasty: anterior hard palate closure (Hans Pichler technique) at three months and posterior soft palate closure (Sommerlad technique) at 12 months. The digitized dental casts were evaluated at three months – pre-surgical (T1) and six years of life– post-surgical (T2). The following linear measurements were analyzed: intercanine (C–C’), intertuberosity (T–T’) distances; anterior dental arch (I–CC’), anterior intersegment (I–C’), and total arch (I–TT’) lengths. The palate area was also measured. Parametric and non-parametric tests were applied (p<0.05). Results In G1, the intragroup comparison showed statistically significant smaller I–CC’ and I–C’ at T2 (p=0.001 and p<0.001, respectively), while T–T’, I–TT’, and area comparisons were significantly greater (p<0.001, p=0.002, and p<0.001, respectively). In G2, the intragroup comparison exhibited statistically significant smaller C–C’ and I–C’ at T2 (p=0.004, for both), whereas T–T’, I–TT’ and area comparisons were significantly greater (p<0.001, p=0.004, and p<0.001, respectively). At T2, the intergroup analysis revealed that G1 had a statistically significant smaller I–CC’ (p=0.014). The analysis of the intergroup differences (∆=T2–T1) showed that G1 had a statistically smaller I–CC’ (p=0.043). Conclusion The two-step palatoplasty showed a more favorable prognosis for the maxillary growth than one-step palatoplasty in children with oral clefts.

Aim to evaluate the surgical effects of two rehabilitation protocols on dental arch occlusion of 5-year-old children with or without cleft lip and palate. Methods this is a retrospective longitudinal study the sample comprised 45 digitized dental casts divided into followed groups: Group 1 (G1) – children who underwent to cheiloplasty (Millard technique) at 3 months and to one-stage palatoplasty (von Langenbeck technique) at 12 months; Group 2 (G2) – children who underwent to cheiloplasty (Millard technique) and two-stage palatoplasty (Hans Pichler technique for hard palate closure) at 3 months and at 12 months to soft palate closure (Sommerlad technique); and Group 3 (G3) – children without craniofacial anomalies. Linear measurements, area, and occlusion were evaluated by stereophotogrammetry software. Shapiro-Wilk test was used to verify normality. ANOVA followed by posthoc Tukey test and Kruskal-Wallis followed by posthoc Dunn tests were used to compared groups. Results For the measures intercanine distance (C-C’), anterior length of dental arch (I-CC’), and total length of the dental arch (I–MM’), there were statistical differences between G1x G3 and G2xG3, the mean was smaller for G1 and G2. No statistically significant differences occurred in the intermolar distance and in the dental arch area among groups. The occlusion analysis revealed significant difference in the comparison of the three groups (p=0.0004). Conclusion The surgical effects of two rehabilitation protocols affected the occlusion and the development of the anterior region of the maxilla of children with oral clefts when compared to children without oral clefts.

Resumo Objetivos: este estudo revisou sistematicamente a literatura para melhor compreender a associação entre COVID-19, gravidez e neonatos. Métodos: MEDLINE, EMBASE, Web of Science, BVS e SCOPUS foram acessadas, considerando os termos: (covid 19 OR covid-19 OR novel coronavirus OR 2019 novel coronavirus OR 2019-nCoV OR sarscov 2 OR sars-cov-2 OR sarscov2 OR sars cov-2) AND (pregnancy OR pregnant OR pregnant women OR gestation OR gestational) AND (infant OR fetal OR neonatal). Trinta textos completos foram incluídos (408 gestantes, 11 mulheres nãogestantes e 279 recém-nascidos). Resultados: febre (45,83%) e tosse (31,61%) foram os principais sintomas da COVID-19 durante a gestação. Baixos níveis de linfócitos (32,10%), elevados níveis de proteínas Creativa (32,35%); leucocitose (29,41%); neutrófilo (5,88%); e alterações radiográficas sob tomografia computadorizada de tórax, radiografia ou ultrasom (45,84%) foram os principais achados laboratoriais. Parto por cesárea e prematuridade foram registrados em 239 e 49 casos, respectivamente. Dez recém-nascidos testaram positivo para o virus SARS-CoV-2. Conclusão: quando a pneumonia COVID-19 afeta mulheres durante a gravidez, os sintomas são semelhantes aos experimentados por mulheres não grávidas. Além disso, ainda não há evidências plausíveis que sugiram a transmissão vertical do vírus SARS-CoV-2 de mãe para filho.

Abstract Objectives: this study systematically reviewed the literature in order to better understand the association among COVID-19, pregnancy and neonates. Methods: MEDLINE, EMBASE, Web of Science, BVS and SCOPUS were assessed, considering the terms: (covid 19 OR covid-19 OR novel coronavirus OR 2019 novel coronavirus OR 2019-nCoV OR sarscov 2 OR sars-cov-2 OR sarscov2 OR sars cov-2) AND (pregnancy OR pregnant OR pregnant women OR gestation OR gestational) AND (infant OR fetal OR neonatal). Thirty full-text were included (408 pregnant women, 11 non-pregnant women and 279 neonates). Results: fever (45.83%) and cough (31.61%) were the main symptoms of COVID-19 during the pregnancy. Low levels of lymphocytes (32.10%), elevated levels of C-reactive protein (32.35%); leukocytosis (29.41%); neutrophil (5.88%); and radiographic alterations on chest CT, x-ray or ultrasound (45.84%) were the main laboratorial findings. Cesarean delivery and preterm were registered in 239 and 49 cases, respectively. Ten neonates tested positive for SARS-CoV-2. Conclusion: when COVID-19 pneumonia affects women during pregnancy, the symptoms are similar to those experienced by non-pregnant women. In addition, there is still no plausible evidence suggesting vertical transmission of SARS-CoV-2 virus from mother to child.

Resumo O objetivo deste estudo foi analisar o crescimento e desenvolvimento maxilar de crianças com fissuras orais por meio de um método inovador da técnica de sobreposição 3D-3D. Participaram do estudo crianças com fissura unilateral completa de lábio (FL) e fissura unilateral de lábio e palato (FLP). As moldagens dos arcos dentários foram realizadas 1 dia antes e 1 ano após o reparo cirúrgico labial. Um scanner a laser 3D digitalizou os modelos dentários e o software do sistema de estereofotogrametria analisou as sobreposições 3D-3D em dois grupos correspondentes (mesmo indivíduo, FL e FLP) e um grupo não-correspondente (indivíduos diferentes). As diferenças foram avaliadas pelo Root Mean Square (RMS) e expressas em milímetros (mm). O teste de Kruskal-Wallis seguido do teste post-hoc de Dunn e teste de MannWhitney foram avaliados para comparar os grupos (α=5%). RMS foi de 1.34 mm (± 0.37) no grupo FL, 1.41 mm (± 0.32) no grupo FLP e 3.38 mm (± 1.28) no grupo não-correspondente. RMS foi significativamente maior no grupo não-correspondente (p <0.0001). Não houve diferenças estatisticamente significativas entre os gêneros. A técnica de sobreposição 3D-3D evidenciou o desenvolvimento da maxila após a cirurgia labial na região anterior do palato. Assim, sugere-se que a amplitude da fenda e a proporção dos segmentos palatinos influenciam na heterogeneidade morfológica e, consequentemente, no desenvolvimento e crescimento maxilar de crianças com fissura orofacial

Abstract This study aimed to analyze the maxillary growth and development of children with oral clefts using the innovative method of 3D-3D superimposition technique. Children with unilateral complete cleft lip (UCL) and unilateral cleft lip and palate (UCLP) participated in the study. The impressions of the dental arches were executed 1 day before and 1 year after lip repair surgery. A 3D laser scanner digitized the dental models and the stereophotogrammetry system software analyzed the 3D-3D superimpositions in two groups of matches (same child, UCL and UCLP) and one group of mismatches (different individuals). The differences were evaluated by Root Mean Square (RMS) and expressed in millimeters (mm). Kruskal-Wallis test followed by post-hoc Dunn test and Mann-Whitney test were assessed to compare the groups (α=5%). RMS was 1.34 mm (± 0.37) in UCL group, 1.41 mm (± 0.32) in UCLP group, and 3.38 mm (± 1.28) in mismatches group. RMS was significantly greater in mismatches than in matches groups (p<0.0001). No statistically significant differences occurred between genders. The 3D-3D superimposition technique showed the maxillary development after lip repair surgery in the anterior region of the palate. Thus, it is suggested that the cleft amplitude and the palatal segments proportion influenced the morphological heterogeneity and, consequently, the development and maxillary growth of children with orofacial cleft.

Resumo A fissura de lábio, alvéolo e palato é uma malformação congênita causada pela falta de fusão dos processos embrionários labial e palatino, que podem comprometer as principais funções do sistema estomatognático. Utilizando o Nordic Orofacial Test - Screening (NOT-S), este estudo transversal observacional, objetivou avaliar a presença da disfunção orofacial nos indivíduos com fissura de lábio, alvéolo e palato em relação a indivíduos sem fissura ou anomalia craniofacial. Cento e vinte indivíduos entre 32 e 65 anos de idade foram selecionados e divididos em dois grupos: pacientes sem fissura labiopalatina (N-CLAP) e pacientes com fissura de lábio, alvéolo e palato (CLAP). Os dois grupos foram combinados por gênero. Cada indivíduo foi entrevistado e submetido a uma avaliação clínica durante a qual o NOT-S foi utilizado para avaliar a disfunção orofacial. O teste de Mann-Whitney comparou desempenho no NOT-S entre os grupos. O teste Qui-Square comparou os domínios NOT-S entre os grupos. A concordância intra-examinador foi K=0,75. Uma comparação dos escores de NOT-S entre os grupos revelou diferenças estatisticamente significativas no gênero (p<0,001), mas não foram encontradas diferenças estatisticamente significativas na comparação de gênero intragrupo. A avaliação dos domínios de NOT-S entre os grupos N-CLAP e CLAP apresentou diferenças estatisticamente significativas nos domínios II (p=0,021), IV (p<0,001) e VI (p=0,002) da entrevista e diferenças significativas em todos os domínios do exame clínico (p<0,001). Indivíduos com CLAP apresentaram maior presença de disfunção orofacial do que os indivíduos sem fissura labioapalatina, conforme avaliado pelo NOT-S.

Abstract Cleft lip, alveolus and palate is a congenital malformation caused by the lack of fusion of the lip and palate embryonic processes, which may disrupt the main functions of the stomatognathic system. Aim: This study aimed to assess the orofacial dysfunction in individuals with cleft lip, alveolus, and palate compared to non-cleft patients. One hundred and twenty individuals between 32 and 65 years of age were selected in the Craniofacial Center and in the School of Dentistry and divided into two groups: non-cleft patients (N-CLAP) and cleft lip, alveolus, and palate patients (CLAP). The two groups were matched by gender. Each individual was interviewed and submitted to a clinical evaluation during which the NOT-S was used to assess orofacial dysfunction. To verify the intra-examiner agreement, the values were compared using the Kappa test. The Mann-Whitney test compared performance on the NOT-S between the groups. The Chi-Square test compared the NOT-S domains between the groups. A comparison of the NOT-S scores between the groups revealed statistically significant differences in gender (p<0.001), but no statistically significant differences in the intragroup gender comparison were found. The assessment of the NOT-S domains between the N-CLAP and CLAP groups exhibited statistically significant differences in domains: breathing (p=0.021), chewing and swallowing (p<0.001), and dryness of the mouth (p=0.002) of the interview and significant differences in all domains of the clinical examination (p<0.001). Individuals with CLAP showed more orofacial dysfunction than non-cleft patients, without gender differences, after being assessed through the NOT-S.

Abstract This study aimed to evaluate the orofacial functions and oral health-related quality of life (OHRQoL) of children with unilateral cleft lip and palate (UCLP). This case-control study included patients with UCLP matched by sex and age with controls (children without UCLP), resulting in the inclusion of a total of 108 eight- to ten-year-old children. Orofacial functions and OHRQoL were evaluated using the Nordic Orofacial Test-Screening (NOT-S) and the Child Perceptions Questionnaire (CPQ 8-1 0 ), respectively. Data normality was assessed by the Kolmogorov-Smirnov test. Differences and correlations in NOT-S and CPQ 8-1 0 scores between and within the groups were evaluated using Mann-Whitney and Spearman´s correlation tests, respectively. The distribution of NOT-S and global ratings of CPQ 8-1 0 for each group were assessed by Chi-squared/Fisher’s Exact tests. The UCLP group had a higher NOT-S total and examination scores than the controls. Dysfunctions related to breathing, facial symmetry/expression, and speech were more frequent in the UCLP patients than in the controls. The UCLP group had higher scores on the social well-being domain than the controls. There was a significant difference between the groups in their ratings in regards to the extent to which their oral condition affected their life overall, with controls perceiving it as somewhat better than patients. In both groups, NOT-S total and interview scores were positively correlated with CPQ 8-1 0 total and domain scores. The NOT-S examination score was only significantly correlated with social domain scores in the control group. The presence of UCLP was associated with clinical signs of orofacial dysfunctions related to breathing, facial symmetry/expression, and speech. Children with UCLP reported more orofacial dysfunctions and negative impacts on social well-being than controls.

Abstract Alternatives for the treatment of caries disease, such as minimally invasive approaches, have been developed in recent years. Objective: To carry out clinical and radiographic evaluations of three cavity liners after selective caries removal. Methodology: Thirty-six primary molars with deep occlusal caries lesions without pulp involvement (from children of both genders, aged between 5 and 8 years) were randomly divided into the following groups: calcium hydroxide cement (CHC) group; mineral trioxide aggregate (MTA) group and Portland cement with added zirconium oxide (PCZ) group. The following-up period was 6- and 12-month. The clinical and radiographic success rates were evaluated through chi-square test. The radiographic measurements were compared by ANOVA followed by Tukey's test (p<0.05). Results: Thirty-six patients were included, but thirty-four returned for 12-month follow-up. The overall success rate of the therapy for the three groups was 94.11% and no statistically significant differences occurred in the comparison among groups (p>0.05). Nineteen radiographs were selected to measure the dentin barrier thickness. The intragroup comparison presented a statistically significant increase of the dentin barrier for all groups, at 12-month follow-up. However, the MTA group showed increase of the dentin barrier, over time, 6- to 12-month follow-up. The intergroup comparison revealed no statistically significant differences (p>0.05). Conclusion: The clinical and radiographic data showed that all cavity liners provided effective treatment of primary teeth after selective caries removal.

Abstract Objectives: To evaluate the effect of calcium hydroxide (CH) associated with two different vehicles as a capping material for pulp tissue in primary molars, compared with mineral trioxide aggregate (MTA). Methodology: Forty-five primary mandibular molars with dental caries were treated by conventional pulpotomy using one of the following materials: MTA only (MTA group), CH with saline (CH+saline group) and CH with polyethylene glycol (CH+PEG group) (15 teeth/group). Clinical and periapical radiographic examinations of the pulpotomized teeth were performed 3, 6, and 12 months after treatment. Data were tested by chi-squared analysis and a multiple comparison post-test. Results: The MTA group showed both clinical and radiographic treatment success in 14/14 teeth (100%), at all follow-up appointments. By clinical evaluation, no teeth in the CH+saline and CH+PEG groups had signs of mobility, fistula, swelling or inflammation of the surrounding gingival tissue. However, in the CH+saline group, radiographic analysis detected internal resorption in up to 9/15 teeth (67%), and inter-radicular bone resorption and furcation radiolucency in up to 5/15 teeth (36%), from 3 to 12 months of follow-up. In the CH+PEG group, 2/11 teeth (18%) had internal resorption and 1/11 teeth (9%) presented bone resorption and furcation radiolucency at all follow-up appointments. Conclusion: CH with PEG performed better than CH with saline as capping material for pulpotomy of primary teeth. However, both combinations yielded clinical and radiographic results inferior to those of MTA alone.

Abstract Purpose To compare, both qualitatively and quantitatively, the inflammatory cells, vascular density and IL-6 immunolabeled cells present in the pulp after pulpotomy with white MTA versus 15.5% ferric sulfate (FS). Methodology Forty-eight mandibular first molars from 24 Wistar rats were divided into MTA or FS groups and subdivided according to the period after pulpotomy procedure (24, 48 and 72 hours). Four teeth (sound and untreated) were used as controls. Histological sections were obtained and assessed through the descriptive analysis of morphological aspects of pulp tissue and the quantification of inflammatory cells, vascular density and interleukin-6 (IL-6) expression. Data were statistically analyzed (p<0.05). Results The number of inflammatory cells was similar in both groups, being predominantly localized at the cervical radicular third. In the MTA group, increased inflammation was observed at 48 hours. Vascular density was similar in both groups and over time, being predominant in the medium radicular third. No correlation was found between the number of inflammatory cells and the vascular density. Pulp tissue was more organized in MTA-treated teeth. In both groups, a weak to moderate IL-6 expression was detected in odontoblasts and inflammatory cells. Comparing both groups, there was a greater IL-6 expression in the cervical radicular third of teeth treated with MTA at 24 hours and in the medium and apical thirds at 72 hours, while in the FS group a greater IL-6 expression was found in the apical third at 24 hours. Conclusion The MTA group presented better histological features and greater IL-6 expression than the FS group. However, no difference was observed between the groups regarding the inflammatory status and vascularization, suggesting the usefulness of FS as a low-cost alternative to MTA.

Abstract The standardization of in situ protocols for dental erosion is important to enable comparison between studies. Objective: Thus, the objectives of this study were to evaluate the influence of the location of in situ intraoral appliance (mandibular X palatal) on the extent of enamel loss induced by erosive challenges and to evaluate the comfort of the appliances. Material and Methods: One hundred and sixty bovine enamel blocks were selected according to their initial surface hardness and randomly divided into two groups: GI - palatal appliance and GII - mandibular appliance. Twenty volunteers wore simultaneously one palatal appliance (containing 4 enamel blocks) and two mandibular appliances (each one containing 2 enamel blocks). Four times per day during 5 days, the volunteers immersed their appliances in 0.01 M hydrochloric acid for 2 minutes, washed and reinserted them into the oral cavity for 2 hours until the next erosive challenge. After the end of the in situ phase, the volunteers answered a questionnaire regarding the comfort of the appliances. The loss of tissue in the enamel blocks was determined profilometrically. Data were statistically analyzed by paired t-test, Chi-square and Fisher's Exact Test (p<0.05). Results: The enamel blocks allocated in palatal appliances (GI) presented significantly higher erosive wear when compared to the blocks fixed in mandibular appliances (GII). The volunteers reported more comfort when using the palatal appliance. Conclusions: Therefore, the palatal appliance is more comfortable and resulted in higher enamel loss compared to the mandibular one.

Resumo O objetivo deste estudo foi avaliar in vitro o efeito antimicrobiano de uma bandagem oral bioadesiva de quitosana com clorexidina para o tratamento de infecções dos tecidos orais. Cinco bandagens de diferentes composições foram testadas: Quitosana 5% (G1); Quitosana 5% ± clorexidina a 0,2% (G2), Quitosana 5% ± clorexidina a 0,6% (G3), Quitosana 5% ± clorexidina a 1,0% (G4) e Quitosana 5% ± clorexidina a 2,0% (G5). Foram testados também 5 tipos de géis nas seguintes composições: Gel de Quitosana 5% (G6), Gel de clorexidina a 0,2% (G7), Gel de clorexidina a 2,0% (G8), Gel de Quitosana 5% ± clorexidina a 0,2% (G9) e Gel de Quitosana 5% ± clorexidina a 2,0% (G10). A ação antimicrobiana das amostras foi testada contra Candida albicans e Streptococcus mutans por meio do antibiograma, medindo o halo de inibição. Os dados foram analisados pelo teste de Kruskal-Wallis e ANOVA a um critério seguido pelo teste de Tukey (p<0,05). A membrana com 2,0% de clorexidina (G5) e os discos contendo gel com 2,0% de clorexidina (G8) apresentaram os maiores halos de inibição para os dois microrganismos, com diferença estatisticamente significativa em relação aos demais grupos testados (p=0,008) apenas nos resultados de inibição de C. albicans. Todas as outras formulações de membranas e géis apresentaram halo de inibição, mas sem diferença estatisticamente significativa. A bandagem oral bioadesiva de quitosana com gel de 2% de clorexidina foi a mais efetiva em inibir os microrganismos testados.

Abstract This study aimed to evaluate in vitro the antimicrobial effect of a bioadhesive chitosan-based oral membrane with chlorhexidine for local treatment of infections in the oral tissues. Five oral membranes of different compositions were tested: 5% chitosan (G1); 5% chitosan ± 0.2% chlorhexidine (G2), 5% chitosan ± 0.6% chlorhexidine (G3), 5% chitosan ± 1.0% chlorhexidine (G4), and 5% chitosan ± 2.0% chlorhexidine (G5). Also, five gel types were tested according to the following compositions: 5% chitosan gel (G6), 0.2% chlorhexidine gel (G7), 2.0% chlorhexidine gel (G8), 5% chitosan gel ± 0.2% chlorhexidine gel (G9), and 5% chitosan gel ± 2.0% chlorhexidine gel (G10). The antimicrobial action of the samples was tested against Candida albicans and Streptococcus mutans through antibiogram by measuring the inhibition halos. Data were statistically analyzed by Kruskal-Wallis and one-way ANOVA followed by Tukey test (p<0.05). The 2.0% chlorhexidine membrane (G5) and the disks containing 2.0% chlorhexidine gel (G8) showed the greatest inhibition halos for both microorganisms, with statistically significant difference when compared to others tested groups (p=0.008) only for Candida albicans inhibitions results. All the other formulations of membranes and gels showed inhibition halos, but without statistically significant difference. The bioadhesive chitosan-based oral membrane with 2% chlorhexidine and 2% chlorhexidine gel were the most effective in inhibiting the tested microorganisms.