Introduction: This study established about 50 anteroposterior and vertical cephalometric norms of five tracing analyses in Iranians, using a large sample.
Methods: Lateral cephalographs of 130 subjects (85 females, 45 males, with an average age of 22.77 ± 2.55 years (range 20-29)) were traced manually using the Ricketts, Holdaway, Z-Merrifield, Epker, and Legan-Burstone soft tissue analyses. The role of age and sex on measurements, as well as the comparisons between Iranian norms with Caucasians from European decent, was determined statistically (α = 0.001).
Results: Age had no significant effect (all P values > 0.01). Sexual dimorphism existed in terms of numerous parameters. Compared to analysis standards, upper lip to E-plane, nose prominence, upper lip thickness, nasomental angle, Z angle, interlabial distance, subnasale perp to chin, subnasale-stomion:stomion-menton, subnasale-lower lip:lower lip-menton, interlabial gap, and vertical lip-chin ratio were smaller in Iranians. Superior sulcus depth, skeletal profile convexity, upper lip strain, upper lip curvature, H-angle, soft tissue chin thickness, nasofacial angle, subnasale perp to upper lip, subnasale perp to lower lip, maxillary prognathism, lower face throat angle, upper lip protrusion, lower lip protrusion, mentolabial sulcus, and lower vertical height-depth ratio were greater in Iranians compared to the norm (P ≤ 0.001).
Conclusions: A great degree of sex dimorphism might exist among Iranians. Many textbook norms might not be the best options for diagnosis or treatment of Iranians.
Keywords: Anthropometry; Ethnic groups; Orthodontic norms; Sex dimorphism; Soft tissue profile.