Prediction of deciduous teeth eruption in Brazilian children: A cross-sectional study nested in a prospective birth cohort (BRISA).

BACKGROUND: Dental eruption is part of a set of children´s somatic growth phenomena. The worldwide accepted human dental eruption chronology is still based on a small sample of European children. However, evidence points to some population variations with the eruption at least two months later in low-income countries, and local standards may be useful. So, this study aimed to predict deciduous teeth eruption from 12 months of age in a Brazilian infant population. METHODS: We developed a cross-sectional study nested in four prospective cohorts - the Brazilian Ribeirão Preto and São Luís Cohort Study (BRISA) - in a sample of 3,733 children aged 12 to 36 months old, corrected by gestational age. We made a reference curve with the number of teeth erupted by age using the Generalized Additive Models for location, scale, and shape (GAMLSS) technique. The explanatory variable was the corrected children´s age. The dependent variable was the number of erupted teeth, by gender, evaluated according to some different outcome distributional forms. The generalized Akaike information criterion (GAIC) and the model residuals were used as the model selection criterion. RESULTS: The Box-Cox Power Exponential method was the GAMLSS model with better-fit indexes. Our estimation curve was able to predict the number of erupted deciduous teeth by age, similar to the real values, in addition to describing the evolution of children's development, with comparative patterns. There was no difference in the mean number of erupted teeth between the sexes. According to the reference curve, at 12 months old, 25% of children had four erupted teeth or less, while 75% had seven or fewer and 95% had 11 or fewer. At 24 months old, 5% had less than 12, and 75% had 18 or more. At 36 months old, around 50% of the population had deciduous dentition completed (20 teeth). CONCLUSION: The adjusted age was an important predictor of the number of erupted deciduous teeth. This outcome can be a variable incorporated into children's growth and development curves, such as weight and height curves for age to help dentists and physicians in the monitoring the children's health.

Influencias dos diferentes tipos de alojamento sobre recem-nascidos na pratica do aleitamento materno / Influence of the different types of room on newborns during breastfeeding

O presente estudo foi realizado no Centro Medico Socialde Vila Lobato, que e um servico ambulatorial primario para criancas e gestantesda Faculdade de Medicina de Ribeirao Preto - FMRPUSP, no periodo de 1 de janeirode 1980 a 31 de dezembro de 1984, abrangendo 132 criancas. O estudo foi longitudinal e retrospectivo, tendo sido possivel constituir dois grupos distintos de criancas, diferindo de acordo com sua permanencia hospitalar no periodo pos-parto,em Alojamento Conjunto e bercario tradicional. Apos a analise estatistica de todas as variaveis envolvidas no estudo, o unico dado que diferencia os dois gruposera o local de internacao no periodo pos-parto. Embora exista uma tendencia a maior amamentacao no grupo que utilizou o Alojamento Conjunto, a analise estatistica mostrou que essa diferenca nao e significativa, devendo-se, porem, consideraro papel importante desempenhado pelo CMSCVL no estimulo a pratica do aleitamentomaterno, o que pode ter homogenizado os dois grupos. O tempo mediano de desmame,encontrado para a populacao estudada de 132 criancas foi de dez meses e para as que ficaram no bercario tradicional, oito meses. Foram identificadas tambem as causas de desmame para a populacao estudada, que se mostraram semelhantes as referidas em outros trabalhos publicados