Relationship between anteroposterior cranial vault deformation and mandibular morphology in a pre-Columbian population

Introduction: An externally applied force to the cranial vault has been reported to affect the growth of the facial skeleton. However, the effect on the mandible is unclear. The purpose of this study was to investigate the relationship between anteroposterior cranial vault deformation and mandibular morphology. Methods: The study sample included 44 women’s crania with intact faces and bases that were excavated from archaeological sites in the Azapa Valley in northern Chile. The crania were divided into anteroposterior deformation (AP) and undeformed (U) groups according to frontal, parietal, and occipital curvatures. The sizes of the cranial vault, middle face, and mandible were measured with calipers. Lateral cephalograms were taken and analyzed according to a conventional method. Results: Cranial base angle, bizygomatic breadth and upper facial height, bicondylar breadth, anterior breadth, and mandibular body length were significantly larger, and the mandibular angle was significantly smaller, in the AP group than in the U group. Conclusions: The anteroposteriorly shorter and wider cranial deformation caused by externally applied forces in infancy might affect the bone-remodeling process of the mandibular angle, leading to a smaller mandibular angle in adulthood.