[Nasal respiratory stenosis and maxillary hypoplasia. Changes after orthodontic treatment with rapid palatal expansion].

The relationship between hypoplasia of the upper maxillary bone and nasal respiratory insufficiency in a group of twenty infants with malocclusion being treated by rapid maxillary expansion (RME) were studied. Prior to treatment all patients presented endognatia with discrepancies of from -4 to -7 mm in the transverse basal skeleton. These were often associated with adenoid hypertrophy (70% of the cases), increased total nasal resistance (70%), oral respiration (80%) and middle ear diseases (30%). RME led to resolution of occlusion alterations in all cases and often also brought about a regression in adenoid hypertrophy (57% of the cases), normalization of the total nasal resistance (70%) and respiration (80%). These effects were achieved alone without association with any other form of medical or surgical E.N.T. treatment. The functional results confirmed by the radiological and clinical findings indicate an increase in the diameters of the nasal fossa and in the distance between the canines, between premolars and between molars as well as reduction in adenoid vegetation and in the diffuse hypertrophic tissues lining the naso-pharyngeal space. Nonetheless, hypoplasia of the upper maxillary bone and nasal respiratory insufficiency remain strictly linked and are bound to a variable, and at times uncertain, cause-effect relationship. Is nasal stenosis the moving force of maxillary-mandibular dysmorphism and gnatological dysfunction or does it result from an overall genetic conditioning of facial skeleton development? During their vast experience in adenoid and metadenoid pathologies in infancy the authors have, at times, observed significant maxillo-facial dysmorphisms. They have likewise found that "facies adenoidea" were not always associated with hypertrophy of the pharyngeal tonsil.(ABSTRACT TRUNCATED AT 250 WORDS)