Comparison of Tweed Facial Triangle Norms Among Different Ethnic Groups

Abstract

Aims: The objectives of the present study were to establish Tweed facial triangle norms in Qatari and to compare the result with Tweed norms and previous reported results in different racial groups. Material and method: The sample consisted of 89 lateral cephalometric radiographic radiographs, 75 patients were females and 14 were males with age range 18 to 25 years old (Mean 20.7. +/-2.3). Results: The result of the present study showed that the mean values of FMA 33.5 º +/- 6.2 º FMIA 52.8 º +/- 9.5 º angles and IMAP  94.5º +/- 8.8º were significantly higher than Tweed norms. The comparison with Black Brazilian and Bangladeshi indicated extremely statistically significant differences in FMA and IMPA angles whereas in Nepalese, extremely significant difference was observed in FMIA and FMA angles. Conclusions: Tweed’s Facial Triangle mean values were established for Qatari. However, Tweed facial triangle norms should be used only as a guide and not as an absolute value. Hence, using specific norms for specific race or ethnic group will help in providing more accurate diagnosis and treatment planning.