Lateral cephalometric norms for adolescent Kuwaitis: soft tissue measurements

The purpose of this study was to establish lateral cephalometric soft tissue norms for adolescent Kuwaitis and to compare these norms to those of the common analysis systems.

Digital lateral cephalograms were made of 82 Kuwaiti boys and 80 Kuwaiti girls, of mean age 13.27 +/- 0.42 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.

The average subject in the sample had a smaller Z angle, a larger H angle, thicker soft tissue at point A and the pogonion, and an increase in most measurements for lip protrusion when compared to the norms of the common analysis systems. The ranges of the majority of facial and labial parameters were larger than those reported in the above-mentioned norms. Gender differences were limited to upper lip length.

Our findings suggest that Kuwaiti norms for lip protrusion should be used when making the extraction decision in adolescent Kuwaiti orthodontic patients. The larger than previously documented variation of the majority of soft tissue parameters suggests a need for establishing different norms for different facial types.