A STUDY OF NASAL RESPIRATORY RESISTANCE AND CRANIOFACIAL DIMENSIONS IN WHITE AND WEST-INDIAN BLACK-CHILDREN

Two studies have shown that there are morphologic differences in the n asopharynx between the major racial groups. This investigation was con ducted to see whether these morphologic differences affected nasal res piration. Twenty-two West Indian and 24 white children (mean age of 13 years 11 months) were studied to examine the relationship between nas orespiratory function and nasopharyngeal and dentofacial structure. Th e nasorespiratory function was measured in terms of nasal respiratory resistance, NRR, (Pascals/cm3 per second), both by anterior and poster ior methods, with a computerized rhinomanometer. Nasopharyngeal struct ure was described in terms of cephalometric variables. The West Indian cephalometric profile generally conformed to its existing description in the literature including prognathic jaws and bimaxillary proclinat ion; in addition, the West Indians were found to have a greater bony n asopharyngeal width (posterior nasal spine-basion) and shallower nasop haryngeal roof angle (posterior nasal spine-hormion-basion). All rhino manometric measurements were significantly lower in the West Indian gr oup, especially when posterior rhinomanometry was used. The correlatio n coefficients between the cephalometric and the rhinomanometric measu rements were statistically significant but low. In addition, the measu re of mandibular prognathism (angle SNB) was also found to be signific antly correlated with the nasorespiratory resistance.