Purpose: Preterm children may not be prepared for extra-uterine life and thus need neonatal intensive care, such as artificial ventilation through orotracheal intubation. Oral tissue development changes as a result of the use of an orotracheal tube and its mechanical influence in preterm neonates has not been intensively studied. The purpose of the present study was to determine the association of orotracheal intubation with incidence of oral alterations in preterm infants. Materials and Methods: A retrospective cohort of 117 subjects who were born during the period 2002-2003 in Brazil were evaluated and the data were analysed using the Fisher and Mann-Whitney exact tests. A 95% confidence interval was calculated for observed oral conditions. Results: The cohort revealed that the most frequent oral conditions included anterior crossbite, superior alveolar contour and palatal deformation. Conclusions: The association between the intubated-infant group and the non-intubated-infant group suggested that mechanical trauma had an influence on the oral structure development. Keywords: malocclusion, oral development, orotracheal intubation, preterm infants