Morphological Observation of the Alar Region between the Piriform Aperture and the Alar Soft Tissue for Facial Approximation (Reconstruction)

Abstract

Prediction methods for regions not lined by facial bones are important elements of forensic anthropology, including forensic facial approximation. The alar region can be predicted by measuring the distances from the piriform margin and multiples of the piriform width. However, studies investigating this region are limited, and some only focus on one side of the alar region. Hence, we aimed to measure the bony points/landmarks to predict the alar region.Post-mortem computed tomography images of the samples from 180 Japanese individuals were obtained and analyzed. The images were processed using Osirix (Pixmeo). The coordinates recorded from all samples were calculated, and the values obtained were stratified by sex, laterality, age, body mass index, and cephalic index. The distances between the alar and the five piriform points were measured. The mean, standard deviation, and confidence interval of all samples were calculated, and the sex-related differences were determined. We evaluated the correlation between alares and other boney landmarks and points. Our findings were compared with those of previous studies. We observed significant sex differences (p < 0.01) and asymmetry (p < 0.01) in laterality in this region; hence, asymmetry was assessed based on these results. Compared with the results of previous studies, the obtained measurements were larger than those of a previous Asian study, suggesting that laterality may influence the accuracy of prediction methods for regions not lined by hard tissues.