## 4 Discussion
The plot suggests no correlation between ontogeny (changes in age) and side of septal deviation, nor between changes in age and magnitude of septal deviation, as confirmed by the multiple linear regression, suggesting that the degree of deviation does not significantly increase in the first stages of life. Indeed, while papers suggest that septal deviation increase with age [48; 49; 55; 56], most of the studies focused on investigating septal deviation from 6 years old to adulthood, with a significant lack of studies focusing on early postnatal years. Our study fills in this gap, with results suggesting that while septal deviation is present at early age stages, changes in age, in this age range, do not impact significantly on septal deviation. A significant association between septal deviation and age at later stages could be explained since as we age, the face is exposed and subject to a growing number of environmental and developmental factors, particularly during adolescence, which can alter and impact its regular development [57]. The asymmetric PCA plot showed a dissociation between changes in patterns of facial asymmetry (which explained 11.07% of the total facial variance) and side of septal deviation, with most of facial asymmetry attributed to fluctuating mechanisms. While previous studies [7; 13] found nasal septum deviation to have an impact on local asymmetries and adjacent morphological elements of the face in adults, the current study is the first analysing the impact on the overall facial architecture and asymmetry during ontogeny, while also controlling for the effect of changes in age and sex. For this purpose, two Multivariate Procrustes ANOVAs were performed to test any potential influence of septal deviation on the symmetric and asymmetric components of facial asymmetry, as well as the impact of the variables of sex and age. Results indicated that only age had an impact on the symmetric component of the face, thus confirming previous studies that showed how significant morphological changes happen in the first postnatal years of life [58]. Finally, using a more traditional approach, a Multivariate Procrustes ANOVA was performed to test the significance of the relation between the overall morphology of the face and the independent variables of septal deviation and fluctuating and directional asymmetry. Results indicate the absence of a significant impact of septal deviation on overall facial morphology, as well as the absence of a significant interaction of facial asymmetry and septal deviation on overall facial shape. Once again, ontogeny (changes in age) plays a crucial role in shaping the face, with fluctuating asymmetry and sexual dimorphism having an impact only under the significance threshold. All the analyses lead to the confirmation of the null hypothesis, as there is no significant link between the magnitude of nasal septum deviation and the asymmetry and general morphology of the face in young specimens from 0 to 8 years old. As stated in the introduction, this could imply a dissociation between the mechanisms of facial growth and nasal septal growth, or that the presence and magnitude of septal deviations and/or facial asymmetry are still relatively low in early postnatal stages. This dissociation could be of interest to surgeons planning craniofacial interventions in infants and children to fix nasal septal deviation, as it seems to suggest a certain level of plasticity and modularity between the nasal septum module and the face, in its asymmetric, symmetric, and overall morphological components. In addition, our findings contribute to the debate on the power of the nasal septum as a pacemaker for facial growth, contributing to the debate on hierarchies of interactions and patterns of craniofacial growth during ontogeny, by suggesting that, in the early stages of life, abnormal development of the nasal septum does not impact significantly on the overall facial architecture and presumably on its functionality. The limitations of this study include a relatively limited sample size.