Reference parameters for normality and associated factors to hard palate during mixed dentition phase.

PURPOSE: To evaluate the association among dimensions of the hard palate according to the sexes, skin color, and periods of the mixed dentition and present reference parameters of normality for this stage of development. METHODS: This cross-sectional study evaluated a representative sample of children between the ages of 7 and 13 years in Santa Maria, southern Brazil. The outcomes of the study were the dimensions of the palate: width measurements and depth. Sociodemographic characteristics and related oral measures were also assessed. Adjusted linear regression model were used to evaluate the effect of the predictor's variables on the dimensions of the hard palate in millimeters. The reference standards for the hard palate normality were presented in mean, standard deviation, and 95% confidence interval. RESULTS: A total of 569 children were evaluated. The hard palate dimensions were larger in the male sex and smaller in the first transitional period of mixed dentition. Skin color had an influence on the hard palate width at the level of the premolars, and the width measurements were smaller in white individuals. Posterior cross bite, Angle Class II and III malocclusions and non-nutritional sucking habits caused reduction in the hard palate width measurements. CONCLUSION: Different dimensions of the hard palate are influenced by demographic variables such as sex, skin color, and mixed dentition period. Children of the female sex, white-skinned and in the first transition period of mixed dentition had smaller dimensions of the hard palate. Establishing normality reference standards in measurements of the palates guides the clinical practice.