Lateral cephalometric norms for adolescent Kuwaitis: hard tissue measurements.

Objective: The purpose of this study was to establish lateral cephalometric hard tissue norms for adolescent Kuwaitis and to compare them with published norms.

Subjects And Methods: Digital lateral cephalograms were made of 162 Kuwaitis (82 boys and 80 girls of mean age 13.27 +/- 0.42 years and 13.21 +/- 0.43 years, respectively), with almost ideal occlusion. Anatomic landmarks were identified directly on the digital images. Linear and angular measurements were calculated electronically using the Dolphin version 9 software package.

Results: The average subject in the sample had a steeper mandibular plane, a more convex profile with a tendency for reduced chin protrusion, and a more protrusive dentition than the norms of the common analysis systems. In addition, the ranges of the skeletal and dentoalveolar parameters were larger than those reported in the above-mentioned norms. Gender differences were limited to maxillary and mandibular length and lower anterior facial height.

Conclusion: The present findings indicate that Kuwaiti norms for incisor inclination and protrusion should be used as a reference when making the extraction decision in Kuwaiti orthodontic patients, and that the variation in skeletal relationships among subjects with satisfactory occlusal compensations is larger than previously documented, suggesting a need for establishing different norms for different skeletal patterns.