Stem cells from human dental pulp and apical papilla : morphological and synchrotron radiation analysis

Dental Mesenchymal stem cells has prompted great for cell-based therapeutics. But no one knows for sure what the true potential of these cells, since most of the studies were done in isolation, using as source, different donors or different cell processi

Epidemiological study of traumatic dental injuries in 5- to 6-year-old Brazilian children

Monitoring traumatic dental injury (TDI) in primary teeth through epidemiological cross-sectional surveys provides descriptive information relevant to the development of public policies focused on the prevention of such injuries for the target population. The aim of this study was to assess the prevalence of TDI in 5- to 6-year-old Brazilian children and its association with biological and socioeconomic factors. A total of 684 children aged 5 to 6 years old, from 11 public schools in the city of Barueri (Brazil) were evaluated. Clinical examinations were carried out in the schools, by two trained and calibrated examiners. Gauze and a mouth mirror were used for the examinations. The reported TDIs were classified according to the Andreasen (2007) criteria for primary teeth. The results showed that 52.3% of the children had TDI. Enamel fracture (63.4%) was the most frequently observed sign of TDI, and the most affected teeth were the primary maxillary central incisors (26.9% maxillary right central incisor and 24% maxillary left central incisor). There was no association between the presence of TDI and biological or socioeconomic factors. In conclusion, the prevalence of TDI was high and had no statistically significant association with biological and socioeconomic factors

Incidence of dental caries in different recall intervals for dental check-up of preschool children with low risk of dental caries: Randomized Clinical Trial

Objetivos: Avaliar a efetividade entre diferentes intervalos de retorno na incidência de cárie em pré-escolares que apresentaram risco baixo de cárie dentária, e também, avaliar o nível de ansiedade e qualidade de vida relacionada à saúde bucal (QVRSB) das crianças de acordo com cada intervalo empregado. Métodos: A amostra foi composta por 224 crianças de escolas públicas, com idade entre 3 a 5 anos, de ambos os sexos, com baixo risco de cárie. As crianças foram alocadas aleatoriamente em dois grupos de estudo, de acordo com dois intervalos de retorno, sendo: Grupo 1 (G1) - exame clínico bucal + escovação dental profissional + orientação de higiene bucal e dieta no intervalo de retorno de 12 meses e Grupo 2 (G2) - exame clínico bucal + escovação dental profissional + orientação de higiene bucal e dieta no retorno de 18 meses. O exame clínico bucal foi realizado por um examinador previamente calibrado e cego aos grupos de estudo e aos desfechos secundários. O exame clínico bucal incluiu o índice de sangramento gengival de Löe, índice de biofilme dentário de Greene e Vermillion simplificado, detecção de lesões de cárie e da sua atividade de acordo com o ICDAS (International Caries Detection and Asessment System). O nível de ansiedade e a QVRSB foram avaliados pela Escala de Imagem Facial e pelo B-ECOHIS, respectivamente, por um dentista externo. O dentista externo também realizou as orientações sobre higiene bucal e dieta, e a avaliação das condições socioeconômicas. Os testes qui-quadrado e o de Mann-Whitney foram utilizados para avaliar a diferença na proporção de crianças e na média de dentes com novas lesões de cárie entre G1 e G2, respectivamente. Análises de Regressão de Poisson com variância robusta foram realizadas para avaliar o desfecho primário de incidência de cárie dentária considerando dois pontos de corte durante os retornos: 1) incidência de lesões de cárie não cavitadas ativas; 2) incidência de lesões cavitadas em dentina. Resultados: Foi observado uma diferença estatisticamente significativa unicamente para a incidência de lesões iniciais de cárie ativas entre os grupos (p=0,012). Na consulta de retorno crianças que pertenciam ao G2 tiveram maior risco de desenvolver lesões iniciais ativas em comparação ao G1 (RR= 2,37; p=0,047) e também aquelas com um maior índice de placa bacteriana (RR=3,14; p<0,001). Crianças que moram em família não nuclear (RR=2,56; p=0,007), com mais de um irmão (RR=2,53; p=0,037), e que utilizavam dentifrício sem flúor ou em baixa concentração no baseline (RR=3,91; p=0,012), tiveram maior risco de desenvolver lesões de cárie iniciais ativas. Crianças com maior número de dentes com lesões iniciais ativas nos retornos tiveram maior risco de desenvolver lesões de cárie cavitadas em dentina (RR=1,62; p=0,001). Conclusões: O intervalo de retorno de 12 meses é mais efetivo na incidência de cárie não cavitada ativa em pré-escolares de baixo risco de cárie, sendo que estas lesões são um fator preditivo para a progressão de lesões de cárie cavitadas em dentina. Porém não há diferenças na escolha do intervalo de retorno para lesões cavitadas em dentina, níveis de ansiedade e QVRSB.Objectives: To assess the effectiveness between different recall intervals on dental caries incidence in preschool children with low risk of caries, as well as, the level of anxiety and oral health-related quality of life (OHRQoL) of children according to each interval applied. Methods: The sample consisted of 224 children from public schools, aged between 3 to 5 years, of both genders, with low risk of caries. The children were randomly allocated into two study groups according to two recall intervals being: Group 1 (G1) - oral clinical examination + professional dental brushing + orientation for oral health and diet on the recall of 12 months and, Group 2 (G2) - oral clinical examination + professional dental brushing + orientation for oral health and diet on the recall of 18 months. A previously calibrated and blinded examiner for study groups and secondary outcomes performed the oral clinical examinations. The examinations consisted of the Löe gingival bleeding index, Greene and Vermillion simplified dental biofilm index, detection of caries lesions and their activity according to the International Caries Detection and Assessment System (ICDAS). An external dentist assessed the anxiety levels and OHRQoL scores by the Facial Imaging Scale and B-ECOHIS, respectively. The external dentist also performed dental hygiene and diet orientations, and the assessment of socioeconomic conditions. The chi-square and Mann-Whitney tests were used to assess the difference in the proportion of children and mean of teeth with new caries lesions between G1 and G2, respectively. Poisson Regression analyses with robust variance were performed to evaluate dental caries incidence considering two cutoff points during the returns: 1) incidence of active non-cavitated caries lesions; 2) incidence of cavitated lesions in dentin. Results: A statistically significant difference was observed only for the incidence of initial active caries lesions between the groups (p=0.012). In the recall interval children who remain in the G2 group and who had a higher plaque index, had a higher risk of developing active lesions (RR=2.37; p=0.047 and RR=3.14; p<0.001, respectively) compared to the G1 group. Children living in non-nuclear families (RR=2.56; p=0.007), with more than one sibling (RR=2.53; p=0.037), and who used fluoride-free or with low concentration in the baseline (RR=3.91; p=0.012) had a higher risk of developing active initial caries lesions. Children with higher number of initial active lesions in the recalls had a higher risk of developing caries lesions cavitated in dentin (RR=1.62; p=0.001). Conclusions: The 12-months recall interval is more effective on the incidence of active non-cavitated caries in preschoolers with low risk caries, which is a predictive factor for the progression of cavitated carious lesions in dentin. There are no differences in the choice of the recall interval for cavitated lesions in dentin, anxiety levels and OHRQoL

Comparison of dynamic cellular response using to different biomaterials: Nanobeads of Hidroxyapatite and Mineral Trioxide Aggregate (MTA)

As células da polpa dental têm o potencial de responder a estímulos externos e reparar o tecido dentário lesionado. Nos dentes, as lesões cariosas profundas e as lesões traumáticas são frequentes e resultam em alterações pulpares. Com o desenvolvimento da ciência e a busca de formas inovadoras de tratamento utilizando biomateriais de tamanho cada vez menor, verificar a biocompatibilidade desses materiais antes da aplicação clínica se mostra necessário e promissor. Assim, a finalidade deste estudo foi avaliar a biocompatibilidade de uma nova nanopartícula de hidroxiapatita utilizando células pulpares humanas em cultura. As Nanopartículas de Hidroxiapatita (HAp) utilizadas em nosso estudo são um material novo e ainda não disponível para a prática clínica. Como parâmetro comparativo, foi utilizado o material já consagrado na Odontologia para tratamentos endodônticos, o Agregado Trióxido Mineral (MTA). Para tanto, foram realizados testes de biocompatibilidade (MTS (3-(4,5-dimetiltiazol-2-y)5-(3-carboximetoxifenil)-2-(4-sulfofenil-2H-tetrazolio)). Foi preparada uma solução de material na concentração de 0,1g/ml diluído em meio de cultura, proporção preconizada pela norma ISO 10.993-12 (ISO, 1996). Esta solução foi diluída em 3 diferentes concentrações (1/10, 1/100 e 1/1000). Também foram realizados testes de migração celular e testes de capacidade de diferenciação, na concentração de 1/100. Como resultados pudemos verificar que as células da polpa foram viáveis quando expostas a diferentes concentrações de HAp, proliferaram mais quando tratadas com HAp na concentração de 1/100, migraram em direção aos materiais estudados e diferenciaram-se em tecido mineralizado quando em contato direto com ambos materiais estudados. Concluímos que o novo material testado é biocompatível e capaz de induzir mineralização em células de polpa dental sugerindo que as HAp podem ter aplicações clínicas futuras em tecidos mineralizados como osso e dente.The dental pulp cells have the potential to respond to external stimuli and repair the dental tissue injury. On teeth, deep carious lesions and traumatic injuries are common and result in pulp changes. With the development of science and the search for innovative treatment forms using reduced size biomaterials, to verify the biocompatibility of these materials before clinical application has become necessary and promising. Thus, the purpose of this study was to evaluate the biocompatibility of a new hydroxyapatite nanoparticle using human pulp cells in culture. The nanoparticles of hydroxyapatite (HAp) used in our study are new material and not yet available for clinical practice. As a comparator, we used the material already used in dentistry to root canal treatment, the Mineral Trioxide Aggregate (MTA). To do so, biocompatibility (MTS (3-(4,5-dimetiltiazol-2-y)5-(3-carboximetoxifenil)-2-(4-sulfofenil-2H-tetrazolio)). A solution of the material in a concentration of 0.1 g / ml diluted in culture medium recommended by ISO 10993-12 (ISO 1996) standard was prepared. This solution was diluted in three different concentrations (1/10, 1/100 and 1/1000). Were also performed cell migration and differentiation capacity assays at a concentration of 1/100. As results, we found that the pulp cells were viable when exposed to different concentrations of HAp, they proliferated more when treated with 1/100 HAp concentration, migrated toward the studied materials and differed into mineralized tissue when there was direct contact with both materials studied. We conclude that the new material tested is biocompatible and able to induce mineralization of dental pulp cells suggesting that the HAp may have future clinical applications in mineralized tissues such as bone and tooth

Follow-up interval for dental appointments: a randomized clinical trial with children with low caries risk.

The objective of this study was to evaluate the effect of different follow-up consultation intervals on caries incidence in children with low caries risk. The study was composed of 224 children aged between 3 and 5 years and with low risk of caries. The children were randomly allocated into two groups, according to two different follow-up consultation intervals: Group 1 (G1) - 12-month follow-up interval; Group 2 (G2) - 18-month follow-up interval. All oral clinical examinations were performed by a single examiner who was previously calibrated and blinded in relation to the study groups. An external dentist provided the advice on oral hygiene and diet and evaluated the children's socioeconomic conditions. The Chi-square and Mann-Whitney tests were used to evaluate the differences between groups. Poisson regression analyses were performed to assess the association of caries incidence with the other variables. At the end of the study there was a significant difference between the groups regarding initial active lesions (p = 0.012), and children in G2 were at a higher risk of developing initial active lesions than those in G1 (p = 0.047). Children who had a higher number of teeth with initial active lesions in the follow-up consultations were at a higher risk of developing cavitated dentin caries (p = 0.001). Both follow-up intervals are justifiable. Although significant results have been observed for initial active caries lesions within the 18-month follow-up interval, it should be noted that these lesions can be treated using just preventive measures. Besides, different return interval had no effect in cavitated dentin lesions

Epidemiological study of traumatic dental injuries in 5- to 6-year-old Brazilian children

Monitoring traumatic dental injury (TDI) in primary teeth through epidemiological cross-sectional surveys provides descriptive information relevant to the development of public policies focused on the prevention of such injuries for the target population. The aim of this study was to assess the prevalence of TDI in 5- to 6-year-old Brazilian children and its association with biological and socioeconomic factors. A total of 684 children aged 5 to 6 years old, from 11 public schools in the city of Barueri (Brazil) were evaluated. Clinical examinations were carried out in the schools, by two trained and calibrated examiners. Gauze and a mouth mirror were used for the examinations. The reported TDIs were classified according to the Andreasen (2007) criteria for primary teeth. The results showed that 52.3% of the children had TDI. Enamel fracture (63.4%) was the most frequently observed sign of TDI, and the most affected teeth were the primary maxillary central incisors (26.9% maxillary right central incisor and 24% maxillary left central incisor). There was no association between the presence of TDI and biological or socioeconomic factors. In conclusion, the prevalence of TDI was high and had no statistically significant association with biological and socioeconomic factors

Prenatal LPS exposure reduces olfactory perception in neonatal and adult rats

Prenatal lipopolysaccharide (LPS) exposure causes reproductive, behavioral and neurochemical defects in both dams and pups. The present study evaluated male rats prenatally treated with LPS for behavioral and neurological effects related to the olfactory system, which is the main sensorial path in rodents. Pregnant Wistar rats received 100 mu g/kg of LPS intraperitoneally (i.p.) on gestational day (GD) 9.5, and maternal behavior was evaluated. Pups were evaluated for (1) maternal odor preference, (2) aversion to cat odor, (3) monoamine levels and turnover in the olfactory bulb (OB) and (4) protein expression (via immunoblotting) within the OB dopaminergic system and glial cells. Results showed that prenatal LPS exposure impaired maternal preference and cat odor aversion and decreased dopamine (DA) levels in the OB. This dopaminergic impairment may have been due to defects in another brain area given that protein expression of the first enzyme in the DA biosynthetic pathway was unchanged in the OB. Moreover, there was no change in the protein expression of the DA receptors. The fact that the number of astrocytes and microglia was not increased suggests that prenatal LPS did not induce neuroinflammation in the OB. Furthermore, given that maternal care was not impaired, abnormalities in the offspring were not the result of reduced maternal care. (C) 2011 Elsevier Inc. All rights reserved.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo, FAPESP[07/56850-1]Fundacao de Amparo a Pesquisa do Estado de Sao Paulo, FAPESP[08/53861-5]Fundacao de Amparo a Pesquisa do Estado de Sao Paulo, FAPESP[09/51886-3]CNPq[301739/2007-2]Paulista University[7-02-747/2010