Objective: The aim of this study was to develop the cephalometric standards for skeletal and dental relationships among a sample of Yemeni population. Material and Methods: One hundred ninety four Yemeni adults (105 females and 89 males) aged 18–25 years, were selected from dental collages in Sana'a. All participants had Class I occlusion with normal growth, facial symmetry, and no previous orthodontic, orthopedic or maxillofacial surgery treatment. A Lateral cephalometric X-ray film was done for all of them. Each film was traced and analyzed using Harvold's cephalometric Analysis. Results: Statistical significant differences were found in the sagittal relationship in SNB, ANB, SNPg and SNBa angles when comparing male with female. No significant difference was seen in SNA angle. In the vertical inclination, statistical significant differences in ML-NL, NL-NSL, ML-NSL and Gn-tgo-Ar variables were found. Yemeni males had statistically significant higher upper and lower facial height then female. No significant difference between genders in the dental relationship variable except the relation between 1-NB line which is statistically higher in female. Conclusion: The results of Yemeni cephalometric features showed ethnic differences in skeletal and dentoalveolar relationship and awareness of the dentofacial pattern of each population will ensure better results of treatment in establishing optimal facial harmony.
