Intérêt d’une approche téléradiographique basée sur les entités trigéminales dans l’étude de la morphologie sagittale de sujets sénégalais

Abstract

The aim of this study was to determine the morphological characteristics of a Senegalese population based on an original cephalometric analysis using landmarks corresponding to the bony entrance or emergence of sensory fibers of the trigeminal nerve. One hundred and five lateral cephalograms of Senegalese patients were assessed in a cross sectional study. The landmarks used were based on cranial foramina i.e. ovale (TO), rotundum (TGR), supraorbital (ESO), infraorbital (TSO), incisive (CPA), lesser palatine (CPP), mandibular (IM) and mental (TM). Seven angular measurements were determined on each cephalogram. t test was used to assess differences in cephalometric variable between subjects grouped according to sex (male and female) and age bracket (< 12 years and > or = 12 years). The Pearson's correlation coefficient was used to analyze the relationship between the cephalometric trigeminal and conventional variables. The significance was set at p < 0.05. The Senegalese mesoface appear to be more retrusive and more divergent when compared with European standard. Regarding sexual differences, TRG-ESO-CPA angle shows significant sexual dimorphism, the maxillary mesofacial prognathism is more important for boys (p = 0.04). When compared to the < 12 years subgroup, the > 12 years subgroup shows significant increase in the mesofacial prognathism and a decrease in the mesofacial divergence but the difference was not significant. Maxillary and mandibular mesofacial prognathism were positively correlated respectively with SNA (r = 0.22; p = 0.021) and SNB (r = 0.28; p = 0.004). The latter were in addition negatively correlated with the mandibular angle Ar-Go-Me (r = - 0.20; p = 0.041). Lastly, the mesofacial divergence angle is positively correlated with the mandibular angle (r = 0.20; p = 0.044) and negatively correlated with SNB (r = - 0.22; p = 0.027). The trigeminal analysis based on true anatomical skeletal points provides a good way to assess facial structures and could allow proper forecasting of the dento-alveolar compensation and complement reliably conventional cephalometric analysis.