An unusual disordered alveolar bone material in the upper furcation region of minipig mandibles: A 3D hierarchical structural study.

Teeth are subjected to compressive loads during mastication. Under small loads the soft tissue periodontal ligament (PDL) deforms most. However when the loads increase and the PDL is highly compressed, the tooth and the alveolar bone supporting the tooth, begin to deform. Here we report on the structure of this alveolar bone in the upper furcation region of the first molars of mature minipigs. Using light microscopy and scanning electron microscopy (SEM) of bone cross-sections, we show that this bone is hypermineralized, containing abundant small pores around 1-5 µm in diameter, lacunae around 10-20 µm as well as larger spaces. This bone does not possess the typical lamellar motif or other repeating structures normally found in cortical or trabecular mammalian bone. We also use high resolution focused ion beam scanning electron microscopy (FIB-SEM) in the serial surface mode to image the 3D organization of the demineralized bone matrix. We show that the upper furcation bone matrix has a disordered isotropic structure composed mainly of individual collagen fibrils with no preferred orientation, as well as highly staining material that is probably proteoglycans. Much larger aligned arrays of collagen fibers - presumably Sharpey's fibers - are embedded in this material. This unusual furcation bone material is similar to the disordered material found in human lamellar bone. In the upper furcation region this disordered bone comprises almost all the volume excluding Sharpey's fibers. We surmise that this most unusual bone type functions to resist the repeating compressive loads incurred by molars during mastication.

Response of the tooth-periodontal ligament-bone complex to load: A microCT study of the minipig molar.

One strategy evolved by teeth to avoid irreversible damage is to move and deform under the loads incurred during mastication. A key component in this regard is the periodontal ligament (PDL). The role of the bone underlying the PDL is less well defined. We study the interplay between the PDL and the underlying alveolar bone when loaded in the minipig. Using an Instron loading device we confirmed that the force-displacement curves of the molars and premolars of relatively fresh minipig intact mandibles are similar to those obtained for humans and other animals. We then used this information to obtain 3D images of the teeth before and after loading the tooth in a microCT such that the load applied is in the third linear part of the force displacement curve. We observed that at many locations there is a complimentary topography of the cementum and alveolar bone surface, strongly suggesting an active interplay between the tooth and the bone during mastication. We also observed that the loaded tooth does not come into direct contact with the underlying bone surface. A highly compressed layer of PDL is present between the tooth and the bone. The structure of the bone in the upper furcation region has a unique appearance with little obvious microstructure, abundant pores that have a large size range and at many locations the bone at the PDL interface has a needle-like shape. We conclude that there is a close interaction between the tooth, the PDL and the underlying alveolar bone during mastication. The highly compressed PDL layer that separates the tooth from the bone may fulfill a key shock absorbing function.

High-Throughput Nanoliter-Scale Analysis and Optimization of Multimodal Chromatography for the Capture of Monoclonal Antibodies.

Multimodal ligands are synthetic molecules comprising multiple types of interactions that have been increasingly used for the capture of different biopharmaceutical compounds within complex biological mixtures. For monoclonal antibodies (mAbs) in particular, these ligands have shown the possibility of direct capture from cell culture supernatants in native conditions, as well as enhanced selectivity and affinity compared to traditional single-mode ligands. However, performing the capture of a target mAb using multimodal chromatography comes with the need for extensive optimization of the operating conditions, due to the multitude of interactions that can be promoted in parallel. In this work, a high-throughput microfluidic platform was developed for the optimization of chromatographic conditions regarding the capture of an anti-interleukin 8 mAb, using a multimodal ligand (2-benzamido-4-mercaptobutanoic acid), under a wide range of buffer pH and conductivities. The interaction of the ligand with the fluorescently labeled target mAb was also analyzed with respect to the individual contribution of the hydrophobic (phenyl) and electrostatic (carboxyl) moieties using fluorescence microscopy. The results were further validated at the macroscale using prepacked columns in standard chromatography assays, and recovery yield values of 94.6% ± 5.2% and 97.7% ± 1.5% were obtained under optimal conditions for the miniaturized and conventional approaches, respectively. In summary, this study highlights that a microfluidic-based approach is a powerful analytical tool to expedite the optimization process while using reduced reagent volumes (<50 µL), less resin (∼70 nL), and delivering results in less than 1 min per assay condition.

The Role of School Social Environment on Dental Caries Experience in 8- to 12-Year-Old Brazilian Children: A Multilevel Analysis.

AIM: Although children spend most of their time involved in activities related to school, few studies have focused on the association between school social environment and oral health. This cross-sectional study assessed individual and school-related social environment correlates of dental caries in Brazilian schoolchildren aged 8-12 years. METHODS: A sample of children from 20 private and public schools (n=1,211) was selected. Socio-economic data were collected from parents, and data regarding children characteristics were collected from children using a questionnaire. Dental examinations were performed to assess the presence of dental plaque: dental caries experience (DMFT≥1) and dental caries severity (mean dmf-t/DMF-T). The social school environment was assessed by a questionnaire administered to school coordinators. Multilevel Poisson regression was used to investigate the association between school social environment and dental caries prevalence and experience. RESULTS: The dental caries prevalence was 32.4% (95% confidence interval: 29.7-35.2) and the mean dmf-t/DMF-T was 1.84 (standard deviation: 2.2). Multilevel models showed that the mean dmf-t/DMF-T and DMFT≥1 were associated with lower maternal schooling and higher levels of dental plaque. For contextual variables, schools offering after-hours sports activities were associated with a lower prevalence of dental caries and a lower mean of dmf-t/DMF-T, while the occurrence of violence and theft episodes was positively associated with dental caries. CONCLUSIONS: The school social environment has an influence on dental caries in children. The results suggest that strategies focused on the promotion of healthier environments should be stimulated to reduce inequalities in dental caries.

Tetrahydrofuran as solvent in dental adhesives: cytotoxicity and dentin bond stability.

OBJECTIVES: The aim of this study was to investigate the cytotoxicity and 1-year dentin bond stability of solvated etch-and-rinse dental adhesives based on tetrahydrofuran (THF), acetone, or ethanol, containing water or not. MATERIALS AND METHODS: Seven primers were prepared using the following solvents: THF, acetone, ethanol, water, THF/water, acetone/water, and ethanol/water. Bovine dentin was used, and specimens for microtensile bond strength (µTBS) test were prepared. Specimens were tested after storage in distilled water for 24 h or 1 year. Cytotoxicity of the solvents was evaluated in 3T3/NIH mouse fibroblasts using a colorimetric 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay after exposure for 24 h. RESULTS: No significant differences were detected among solvents after storage for 24 h, except for the water-based group, which showed the lowest µTBS values. After storage for 1 year, the THF-based adhesive system resulted in more stable bonds. Yet, THF showed an intermediate cytotoxicity when compared with the other solvents, being less toxic than phosphate monomer and similar to 2-hydroxyethyl methacrylate. CONCLUSION: THF seems to be a suitable solvent for adhesive systems. CLINICAL RELEVANCE: THF is a promising solvent that can be used to improve dentin bond stability.

FAAH rs324420 Polymorphism: Biological Pathways, Impact on Elite Athletic Performance and Insights for Sport Medicine.

Gene variation linked to physiological functions is recognised to affect elite athletic performance by modulating training and competition-enabling behaviour. The fatty acid amide hydrolase (FAAH) has been investigated as a good candidate for drug targeting, and recently, its single-nucleotide polymorphism (SNP) rs324420 was reported to be associated with athletic performance. Given the implications, the biological pathways of this genetic polymorphism linked to elite athletic performance, considering sport type, psychological traits and sports injuries, need to be dissected. Thus, a narrative review of the literature concerning the biological mechanisms of this SNP was undertaken. In addition to its role in athletic performance, FAAH rs324420 is also involved in important mechanisms underlying human psychopathologies, including substance abuse and neural dysfunctions. However, cumulative evidence concerning the C385A variant is inconsistent. Therefore, validation studies considering homogeneous sports modalities are required to better define the role of this SNP in elite athletic performance and its impact on stress coping, pain regulation and inflammation control.

Sleep and Awakening Quality during COVID-19 Confinement: Complexity and Relevance for Health and Behavior.

OBJECTIVE: The aim of this study was to evaluate sleep and awakening quality (SQ and AQ) during COVID-19 in a large and diversified population in order to identify significant associations and risks in terms of demography, health and health-related behaviors, sleep variables, mental health, and attitudes. METHODS/RESULTS: Online surveys were used for data collection, received from 5479 individuals from the general population, sleep disorder patients, and COVID-involved (medical doctors (MDs) and nurses) and COVID-affected professionals (teachers, psychologists, and dentists). SQ and AQ were worse in adults, females, and high-education subjects. Feeling worse, having economic problems, depression, anxiety, irritability, and a high Calamity Experience Check List (CECL) score during COVID were significantly associated with poor SQ and AQ. Shorter sleep duration, increased latency, poor nutrition, low physical activity, increased mobile and social network use, more negative and less positive attitudes and behaviors were associated with poor AQ. CONCLUSIONS: The SQ logistic regression showed gender, morbidities, CECL, and awakenings as relevant, whereas, for AQ, relevant variables further included age and physical activity. Aiming to have a high stress compliance, each individual should sleep well, have important control of their mood, practice positive behaviors while dismissing negative behaviors and attitudes, practice exercise, have adequate nutrition, and beware of technologies and dependences.

Anatomical parameters of the body and the digestive tract of Callithrix sp. marmosets under the influence of seasonality.

Due to the ecological importance and given the scarcity of studies on the digestive morphology of primates, anatomical aspects of the body and digestive tract, as well as food content were analysed for marmosets Callithrix sp. (hybrids of exotic species) captured in forest fragments in Minas Gerais - Brazil, during the dry and rainy seasons, considering that seasonal variations affect the availability of food and quality of diet. Data such as body weight and length, and thoracic and abdominal perimeters were analysed, and no significant difference was found between dry and rainy seasons. In relation to the digestive tract, length, weight and diameter of the oesophagus, stomach, small intestine and large intestine were measured, in addition to the isolated caecum. There was a significant difference in the diameter of the ascending colon, which was larger in the animals in the dry season than in the rainy season. The difference found may be related to diet, and through analysis of the gastric and caecal contents, it was observed that gum was the main food item for the dry season marmosets, while in the rainy season the animals consumed mainly arthropods. Thus, the characteristic observed in the digestive tract of dry season marmosets is a reflection of an adaptive response to gum intake, since this food item is of low digestibility, necessitating that the food content be retained for a long time in this segment of the large intestine, helping the process of microbial fermentation and better energy utilization for these animals.

Enzymatic activities and protein profile of latex from Calotropis procera.

The laticifer fluid of Calotropis procera is rich in proteins and there is evidence that they are involved in the pharmacological properties of the latex. However, not much is known about how the latex-containing proteins are produced or their functions. In this study, laticifer proteins of C. procera were pooled and examined by 1D and 2D electrophoresis, masses spectrometry (MALDI-TOF) and characterized in respect of proteolytic activity and oxidative enzymes. Soluble laticifer proteins were predominantly composed of basic proteins (PI>6.0) with molecular masses varying between 5 and 95 kDa. Proteins with a molecular mass of approximately 26,000 Da were more evident. Strong anti-oxidative activity of superoxide dismutase (EC 1.15.1.1) (1007.74+/-91.89 Ug(-1)DM) and, to a lesser extent ascorbate peroxidase (EC 1.11.1.1) (0.117(d)+/-0.013 microMol H(2)O(2)g(-1)min(-1)), were detected. However, catalase (EC 1.11.1.6) was absent. The strong proteolytic activities of laticifer proteins from C. procera were shown to be shared by at least four distinct cysteine proteinases (EC 3.4.22.16) that were isolated by gel filtration chromatography. Serine and metaloproteinases were not detected and aspartic proteinase activities were barely visible. Chitinases (EC 3.2.1.14) were also isolated in a chitin column and their activities quantified. The presence of these enzymatic activities in latex from C. procera may confirm their involvement in resistance to phytopathogens and insects, mainly in its leaves where the latex circulates abundantly.

Is obesity associated to dental caries in Brazilian schoolchildren?

This cross-sectional study aimed to determine the association between dental caries and weight status, and between dental caries and physical activity in Brazilian schoolchildren aged 8 to 12 years. A multi-stage sample of children enrolled in 20 private and public schools in 2010 in Pelotas, Southern Brazil, were invited to participate in the study. Socioeconomic data were collected from parents, and data regarding children characteristics were collected from children using a questionnaire and anthropometric measures. The Body Mass Index was obtained, and children were classified as overweight/obese considering age and sex. Dental examinations were performed to assess the presence of gingival inflammation, dental caries prevalence (DMFT≥1) and dental caries experience (mean DMFT). Multivariate Poisson Regression was used to assess factors associated with dental caries prevalence and experience. A total of 1,210 children were included in the study. Dental caries prevalence was 32.4% (95% CI 29.7-35.2), while the mean DMFT was 0.64 (± SD 1.00). Children who practiced less than 300 minutes per week of physical activity and overweigh/obese children had lower prevalence of dental caries, while children with obesity or overweight presented lower dental caries experience. Obesity/overweight and physical activity level presented an inverse relationship with dental caries. Longitudinal studies investigating the complexity of this relationship are required.

Por que ainda insisto na terapia comunitária? relato de uma experiência formativa e prática / Why do i still insist on community therapy? report of a formative and practical experience / ¿Por qué aún insisto en la terapia comunitaria? informe de experiencia formativa y práctica

A Terapia Comunitária Integrativa valoriza as histórias de vida dos participantes, o resgate da identidade, a restauração da autoestima e da confiança em si e a ampliação da percepção dos problemas e das possibilidades de resolução a partir das competências locais, ou seja, torna o indivíduo mais autônomo e independente. O objetivo deste estudo foi descrever a experiência formativa e a prática da Terapia Comunitária Integrativa. Trata-se de um relato desenvolvido em duas Unidades Primárias de Atenção à Saúde no município de Horizonte, estado do Ceará. Este trabalho teve início a partir da proposta formativa lançada pela Residência Integrada em Saúde da Escola de Saúde Pública do Ceará. A equipe de terapeutas residentes foi composta por três profissionais: uma assistente social, uma cirurgiã-dentista e uma educadora física. As rodas terapêuticas ocorreram em duas unidades de saúde. Um dos desafios que mais persistiu foi a mobilização da comunidade, pois foi observada, durante todo o processo, a variação do público participante, no que diz respeito ao gênero, à idade e ao papel desenvolvido na comunidade. A equipe valorizou o vínculo, tecendo redes de acesso, disponibilizando-se enquanto equipe de terapeutas e demonstrando a importância do cuidado que vai além da clínica. Foi proposta outra forma de cuidado, que valoriza a autonomia do sujeito e sua capacidade, lembrando sempre que há uma identidade na comunidade e que juntos somos mais fortes.

Integrative Community Therapy values the life histories of participants, the recovery of identity, the restoration of self-esteem and self-confidence, and the broadening of perceived problems and possibilities for resolution based on local competences, that is, it creates a more autonomous and independent individual. Thus, this study describes the formative and practical experience of Integrative Community Therapy. An experience report was developed in two Primary Health Care Units at Horizonte, municipality in the state of Ceará, Brazil. This research stemmed from the formative proposal launched by the Integrated Residency in Health, School of Public Health, Ceará. The team of resident therapists consisted of three professionals: a social worker, a dental surgeon, and a physical educator. Therapeutic rounds took place in two Health Units. A persistent challenge concerned mobilizing the community, as the participating public varied throughout the process regarding gender, age, and the role developed in the community. The team valued the bond, weaving access networks, making themselves available as a team of therapists, and showing the importance of care that goes beyond the clinic. They proposed another form of care, one that values the subject's autonomy and ability, without forgetting the community identity and that together we are stronger.

La Terapia Integrativa Comunitaria valora las historias de vida de los participantes, la recuperación de la identidad, la restauración de la autoestima y confianza en sí mismos, la ampliación de la percepción de los problemas y las posibilidades de resolución con base en competencias locales, es decir, hace que el individuo sea más autónomo e independiente. El objetivo de este estudio fue describir la experiencia formativa y práctica de la Terapia Integrativa Comunitaria. Se trata de un informe elaborado en dos Unidades de Atención Primaria de Salud del municipio de Horizonte, en el estado de Ceará (Brasil). Se inició con la propuesta formativa lanzada por la Residencia Integrada de Salud de la Escuela de Salud Pública de Ceará. El equipo de terapeutas residentes estuvo integrado por tres profesionales: una trabajadora social, una dentista y una profesional de educación física. Las rondas terapéuticas se llevaron a cabo en dos Unidades de Salud. Uno de los desafíos que más persistió fue la movilización de la comunidad, ya que se observó a lo largo del proceso la variación del público participante en cuanto al género, la edad y el rol desarrollado en el comunidad. El equipo valoró el vínculo, estableció redes de acceso y se puso a disposición como equipo de terapeutas demostrando la importancia de una atención que va más allá de la clínica. Se propuso otra forma de cuidado, que valora la autonomía y capacidad del sujeto, recordándoles que siempre hay una identidad en la comunidad y que juntos somos más fuertes.

Formulation and Evaluation of a Mucoadhesive Thermoresponsive System Containing Brazilian Green Propolis for the Treatment of Lesions Caused by Herpes Simplex Type I.

The aim of the present work was to develop a topical delivery system that contains Brazilian green propolis extract (PE-8) to increase efficiency and convenience when applied to herpetic lesions. The cytotoxicity and antiherpetic activity was determined in vitro and in vivo. The PE-8 was added to a system that contained poloxamer 407 and carbopol 934P. The in vitro characterization of the system included rheological studies, texture profile analysis, and mucoadhesion analysis. The PE-8 inhibited the virus during the phase of viral infection, induced virion damage, and exhibited an ability to protect cells from viral infection. The system had advantageous mucoadhesive properties, including a suitable gelation temperature of approximately 25°C for topical delivery, a desirable textural profile, and pseudoplastic behavior. The in vitro release study showed a rapid initial release of the PE-8 in the first 3 h, and the rate of drug release remained constant for up to 24 h. The system appeared to be macroscopically and microscopically innocuous to skin tissue. Therefore, the mucoadhesive thermoresponsive system that contained the PE-8 appears to be promising for increasing bioavailability and achieving prolonged release of the PE-8 when applied to skin lesions caused by herpes simplex virus type 1.

Effect of alendronate on healing of bone defect and gingival tissue in osteopenic rats / Efecto del alendronato en la reparación de defectos óseos y tejido gingival en ratas con osteopenia

The aim was to evaluate bone repair and gingival tissue repair in osteopenic rats. Fifteen female wistar rats were included; in all of them ovariectomy was realized to induce osteopenia; after 45 days, the animals were submitted to 2 surgical techinques 1) dental extraction of the upper central incisor with no socket preservation and 2) 5 mm cranial defect in the calvarium; 5 rats were included in the control group (G1) withput alendronate application; in the group 2 (G2) was used subcutenous alendronate (0.5 mg/kg) once for three weeks and then was realizd the both surgical techniques. In group 3 (G3), after ovariectomy was realized the both dental extraction and the calvarium defect and after that was realized the alendronate protocol. In each group, after six week was realized euthanasia and descriptive histological analysis of the surgical areas involved. In bone formation of the 5 mm cranial defect was observed with good progression in the 3 experimental models and no modification in quality of bone repair was observed. For the gingival tissue in the extraction socket, no differences were observed between G1 and G3. On other hand, in G2 a thinner and reduced gingival epithelium was found. Our results showed that alendronate was not an obstacle for bone repair; deficiencies in re-epithelialization of oral mucosa show the impact of alendronate before dental extraction.

El objetivo fue evaluar la reparación ósea y gingival en ratas con osteopenia. Quince ratas wistar hembras fueron incluidas; en todas ellas se realizo ovarectomia y fue realizada la inducción de osteopenia; después de 45 días, los animales fueron sometidos a dos técnicas quirúrgicas 1) extracciones dentales del incisivo central superior sin preservación alveolar y 2) creación de un defecto craneano de 5 mm en la calota; 5 animales fueron incluidos como grupo control (G1) sin la aplicación de alendronato; en el grupo 2 (G2) se utilizó alendronato subcutáneo (0,5 mg/kg) una vez a la semana durante 3 semanas. En el grupo 3 (G3), después de la ovarectomia se realizó la exodoncia y el defecto en el cráneo y después de ello se inicio el protocolo con alendronato. En cada grupo, después de seis semanas se realizó la eutanasia con descripción histológica de los hallazgos. En el hueso formado en el defecto craneano de 5 mm se observó una adecuada progresión de reparación en los 3 modelos experimentales y no se observó cambios importantes en el modelo de reparación. Para el tejido gingival en el sitio de extracción, no se observaron diferencias entre el grupo G1 y G3. Por otra parte, el G2 presentó un tejido mas delgado con reducción del epitelio gingival; nuestros resultados demuestran que el alendronato no fue un obstáculo en la reparación ósea; deficiencias en la re epitelización de la mucosa oral muestran el impacto del alendronato después de la exodoncia.

Enzymatic properties of a neutral endo-1,3(4)-beta-xylanase Xyl II from Bacillus subtilis.

A Bacillus sp. CCMI 966, characterised as Bacillus subtilis, has a duplication time of about 24 min. It produces at least two extracellular xylanases, Xyl I and Xyl II. The extracellular xylanase activity seems to be strongly correlated with the biomass growth profile. The Xyl II isoenzyme was purified by ammonium sulphate precipitation and anionic exchange chromatography, with a purification factor of 8.3. The molecular weight of the isoenzyme was estimated by SDS-PAGE revealing that Xyl II is a multimeric enzyme with a catalytic subunit of about 20 kDa. Under non-denaturing conditions, a molecular weight of about 340 kDa was obtained by native PAGE gel and of 20 kDa by gel filtration chromatography. The enzyme showed an optimum pH and temperature of 6.0 at 60 degrees C. Xyl II was stable at 40 degrees C for 180 min at pH 6.0. The specificity of Xyl II for different substrates was evaluated. Xyl II presents a higher affinity towards OSX, with a K(m) of 1.56 g l(-1) and showed the ability to hydrolyse laminarin, with a K(m) of 1.02 g l(-1). Xylotetraose is the main product of xylan degradation. The Xyl II ability for binding to cellulose and/or xylan was also studied.

Preferences on vital and nonvital tooth bleaching: a survey among dentists from a city of southern Brazil.

This study evaluated the preferences of general dentists regarding vital and nonvital tooth bleaching therapies and investigated whether the time of clinical practice and post-graduate training influence these options. A cross-sectional study was conducted using a questionnaire with closed questions applied to dentists (n=276) of a mid-sized city of the southern Brazil (Pelotas, RS). Information was collected regarding sociodemographic variables, level of specialization and time since graduation. In addition, options regarding bleaching therapies including the first choice of material, technique and clinical practice for vital and nonvital tooth bleaching therapies were included. Data were submitted to descriptive analysis and the associations were evaluated using chi-square and Fisher exact tests (α=0.05). The response rate was 68% (n=187). At-home bleaching therapy was broadly preferred (78.1%) over in-office (21.9%) bleaching. For at-home bleaching, most dentists answered to use 10% carbamide peroxide (CP) (40.2%) and >30% hydrogen peroxide (HP) (31.7%) for nonvital therapies. The majority of dentists with post-graduation training preferred at-home bleaching techniques (p=0.003). At-home bleaching therapy was also more indicated by younger dentists. No association was found between the choice for nonvital bleaching therapies and time since graduation (p=0.532) or continuous education (p=0.083). In conclusion, at-home bleaching was preferred over in-office therapies; 10% CP and >30% HP were chosen as first option agents to treat discolored vital and nonvital teeth, respectively. The time in clinical practice and the level of specialization affected dentists' choices only for vital tooth bleaching treatment.

1,3-Diethyl-2-thiobarbituric acid as an alternative coinitiator for acidic photopolymerizable dental materials.

The ethyl-4-dimethylaminobenzoate (EDAB) is widely used as a coinitiator of the camphorquinone (CQ), but in acidic circumstances it might present some instability, reducing the polymerization efficiency of the material. Considering this, new coinitiators are being evaluated. Hence, this study evaluated the kinetic of polymerization (KP), the degree of conversion (DC), and the rate of polymerization (RP ) of experimental resin adhesives containing 1,3-diethyl-2-thiobarbituric acid (TBA) as a coinitiator of the CQ. The experimental monomeric blend was prepared with bisphenol A glycidyl dimethacrylate, 2-hydroxyethyl methacrylate, and acidic monomers. CQ was added at 1 mol % as photoinitiator. Six groups were formulated: four containing concentrations of 0.1, 0.5, 1, and 2 mol % of TBA, one without coinitiator, and the last one containing 1 mol % of EDAB (control group). The KP and the RP were performed using real-time Fourier Transform infrared spectroscopy. The group without coinitiator has not formed a polymer, whereas the addition of TBA resulted in the conversion of monomers in polymer. The DC of the adhesives was as higher as the increase in the TBA content. The group with 2 mol % of TBA presented improved DC and reactivity (RP ) than the other groups and the control one. Hence, the TBA has performed as a coinitiator of the CQ for the radical polymerization of methacrylate resin adhesives and it has improved the DC and the reactivity of the materials. Thus, it is a potential coinitiator for the photopolymerization of dental materials.

Is obesity associated to dental caries in Brazilian schoolchildren?

Abstract This cross-sectional study aimed to determine the association between dental caries and weight status, and between dental caries and physical activity in Brazilian schoolchildren aged 8 to 12 years. A multi-stage sample of children enrolled in 20 private and public schools in 2010 in Pelotas, Southern Brazil, were invited to participate in the study. Socioeconomic data were collected from parents, and data regarding children characteristics were collected from children using a questionnaire and anthropometric measures. The Body Mass Index was obtained, and children were classified as overweight/obese considering age and sex. Dental examinations were performed to assess the presence of gingival inflammation, dental caries prevalence (DMFT≥1) and dental caries experience (mean DMFT). Multivariate Poisson Regression was used to assess factors associated with dental caries prevalence and experience. A total of 1,210 children were included in the study. Dental caries prevalence was 32.4% (95% CI 29.7-35.2), while the mean DMFT was 0.64 (± SD 1.00). Children who practiced less than 300 minutes per week of physical activity and overweigh/obese children had lower prevalence of dental caries, while children with obesity or overweight presented lower dental caries experience. Obesity/overweight and physical activity level presented an inverse relationship with dental caries. Longitudinal studies investigating the complexity of this relationship are required.

Tratamento de fobia específica por dessensibilização e reprocessamento por meio dos movimentos oculares / Treatment of specific phobia through eye movement desensitization and reprocessing / Tratamiento de la fobia específica por desensibilización y reprocesamiento a traves de los movimientos oculares

A fobia específica é caracterizada pela presença de um medo persistente e recorrente que é excessivo e irracional a um objeto ou situação específica que desencadeia uma forte reação de ansiedade. Diversos estudos têm sido realizados com intuito de avaliar a eficácia da dessensibilização e reprocessamento através dos movimentos oculares (EMDR), e tem sido comprovado que é um método bem-sucedido para tratamento de fobia específica, ansiedade, depressão, traumas e queixas somáticas. O caso do presente artigo descreve o trabalho terapêutico realizado com uma mulher de 42 anos com fobia a próteses dentárias através da intervenção EMDR. No final da intervenção, a paciente perdeu o medo às próteses, já não revelando respostas de ansiedade e de desconforto, mantendo-se estável durante o período de follow-up, um mês após a intervenção. Esses resultados repercutiram-se na melhoria da sua qualidade de vida, ao nível da sua vida pessoal, social e profissional.

The specific phobia is characterized by a persistent and recurring fear that is excessive and irrational to a specific object or situation, triggering a strong anxiety reaction. Several studies have been conducted in order to assess the effectiveness of eye movement desensitization and reprocessing (EMDR) and it has been proven to be a successful method for the treatment of specific phobias, anxiety, depression, trauma and somatic complaints. The case of this article describes the therapeutic work done with a forty-two years old’ woman that has phobia to dentures using the intervention of EMDR. At the end of the intervention, the patient lost the fear of prosthetics, no longer revealing responses of anxiety and discomfort and remained stable during the follow-up one month after the intervention. These results had an impact on improving their quality of life, in terms of her personal, social and professional life.

La fobia específica se caracteriza por la presencia de un miedo persistente y recurrente que es excesivo o irracional a un objeto o situación especifica que desencadena una fuerte reacción de ansiedad. Varios estudios han sido realizados con el fin de evaluar la eficacia de desensibilización y reprocesamiento mediante estudio de los movimientos oculares (EMDR) y ha sido comprobado que es un método exitoso para el tratamiento de la fobia específica, ansiedad, depresión, traumas y quejas somáticas. El presente artículo describe el trabajo terapéutico realizado con una mujer de cuarenta y dos años con fobia a prótesis dentarias a través de la intervención EMDR. En el final de la intervención, la paciente perdió el miedo a las prótesis, no evidenciando señales de ansiedad y de desconforto, manteniéndose estable durante el periodo de follow-up, un mes después de la intervención. Eses resultados repercutieran en una notable mejoría de su calidad de vida a nivel personal, social y profesional.

Color stability of a nanofill composite: effect of different immersion media.

OBJECTIVE: The aim of this in vitro study was to evaluate the color stability of a nanofill composite resin (Filtek Z350) in different immersion media. MATERIALS AND METHODS: Twelve resin-based composite specimens were prepared using a silicon cylindrical mold measuring congruent with 1mm of thickness and congruent with 10mm of diameter. Specimens were light-cured for 40 s from both sides using a LED Radii at 1400 mW/cm(2) and were randomized into 4 groups (n= 3) according to immersion media: coffee, yerba mate, grape juice or water (control solution). A digital spectrophotometer was used to evaluate the color changes at baseline and at 1-week after immersion in each solution. Specimens were stored in the different staining media for 4 h/day during 1 week. The color differences (DE) were analyzed by paired t-test and one-way ANOVA with complementary Tukey test (p<0.05). RESULTS: After 1-week of immersion, a perceptive color change for the group stored in the grape juice compared to baseline (p=0.008) was observed. Coffee and yerba mate did not show any color changes visible for the human eyes or significantly different from the control group (p>0.05) CONCLUSIONS: The findings of the present study suggest that the tested nanofill resin-based composite was susceptible to staining by substances present in the grape juice.

Histologic and histomorphometric study of bone repair around short dental implants inserted in rabbit tibia, associated with tricalcium phosphate graft bone / Estudo histológico e histomorfométrico do reparo ósseo ao redor de implantes dentários curtos instalados em tíbias de coelhos associado ao uso do enxerto de fosfato tricálcio

The use of short dental implants represents one way to overcome this limitation, in association with bone grafting procedures. Tricalcium phosphate-based grafts are among those widely used. The purpose of this study was to assess the biocompatibility of this biomaterial in the coverage of bone defects around short dental implants. Ten New Zealand rabbits were used in this study, each animal received 4 implants, two were placed in the right tibia region (control group) and two in the left tíbia region (test group). Forty implants were used, with 4mm diameter and 6mm length. For the control group, holes 6 mm deep were made, and the implants were then inserted at the level of bone tissue. In the control group, the implants of 6 mm in length were inserted to its full length, while in the test group, the same implant was inserted up to 4 mm and left exposed 2 mm. These 2 mm exposed were coated with a bone substitute of tricalcium phosphate and a collagen membrane. After three months, the animals were prepared for histomorphometric analysis, which showed that the control group had a higher number of osteoblasts per µm2 than the test group (p < 0.001). It was concluded that under these experimental conditions, tricalcium phosphate showed tissue biocompatibility and osteoconductive potential.

Para a instalação de implantes em pacientes que possuem perdas ósseas, surgiram os implantes curtos e enxertos ósseos como uma opção de tratamento. Um enxerto que vem sendo utilizado é o biomaterial à base de fosfato tricálcio. O objetivo deste trabalho foi avaliar microscopicamente a neoformação óssea ao redor de implantes curtos. Para este estudo foram necessários dez coelhos da raça Nova Zelândia, sendo que cada animal recebeu quatro implantes, instalados dois na região da tíbia direita (controle) e dois na esquerda (teste). Foram utilizados 40 implantes com diâmetro de 4 mm e comprimento de 6 mm. No grupo controle, implantes de 6 mm foram inseridos no seu comprimento total, enquanto no grupo teste, o mesmo implante de 6 mm foi inserido apenas 4 mm, deixando expostos 2 mm. Esses 2 mm expostos foram cobertos com o enxerto de fosfato tricálcio e uma membrana de colágeno. Após três meses, os animais foram sacrificados para realizar os testes de resistência e a análise histomorfométrica. Na análise histomorfométrica, o grupo controle apresentou maior número de osteoblastos por µm2 do que o grupo teste (p-valor < 0,001). Concluímos que enxertos à base de fosfato tricálcio possuem biocompatibilidade tecidual e potencial osteocondutivo na neoformação óssea ao redor dos implantes.