The aim of this study was to verify whether sucking habits influence the position of the primary incisors. The sample comprised 34 preschool children (mean age 44 months ± 9 months). They were divided into three groups: group B (n = 9) with a baby bottle habit; group BP (n = 13) with baby bottle and pacifier habits; and a control group C (n = 12) with no sucking habit. Data were derived from face-to-face interviews with the parents/guardians, oral examinations, study casts, facial photographs (frontal/lateral views), and cephalograms. The cephalograms were scanned and subsequently analyzed by one trained and calibrated operator. The cephalometric parameters recorded were: interincisal angle (U1/L1), U1/NA (angle/distance), and L1/NB (angle/distance). The data were analyzed using Stata 7.0. The Kruskall-Wallis test was used to compare the cephalometric measurements in the children with and without sucking habits. The level of significance was set at P ≤ .05. This study found a significant relationship between existing sucking habits and a protrusion of the maxillary and mandibular primary incisors. World J Orthod 2009;10:229–232.