Sexual Dimorphism of Calvarial Thickness Parameter in Different Skeletal Patterns

Abstract

The purpose of the current study was to evaluate the calvarial thickness parameter
in both genders, and in different skeletal patterns. The sample included 120
pretreatment digital lateral cephalometric radiographs of Iraqi subjects (60 males and
60 females) aged between 17 to 30 years, attending Orthodontic Clinic in the College
of Dentistry; Baghdad University, and private clinics in Baghdad city. The 120
radiographs were divided into 3 groups (40 radiographs for each group) according to
the ANB angles: ANB angle smaller than one degree (Class III), between two and
four degrees (Class I), and larger than four degrees (Class II), each group was further
subdivided into two subgroups according to gender (20 radiographs for each gender).
Four linear measurements were used exclusively in the assessment of calvarial
thickness parameter in both genders.
The mean calvarial thickness values changed from highest to lowest in sphenoid,
parietal, occipital, and frontal bones respectively. In the skeletal class II malocclusion
the frontal and occipital bones' thickness showed highly significant gender differences
(P<0.01) using Student's t- test, with females had thicker frontal bone than males, and
males had thicker occipital bone than females, in addition the skeletal glass II group
showed no significant gender difference (P>0.05) regarding sphenoid and parietal
bones' thickness. The most vital outcomes of the present study were the frontal and
occipital bones can be used as important key bones for understanding the calvarial
phenotypic description and sexual dimorphism in different skeletal patterns, while the
sphenoid and parietal bones can be used as reference bones for standardization of
cephalometric analysis.