Concordance of the facial biotype between Bjork-Jarabak cephalometrics and photographic analysis of the facial opening angle

BACKGROUND: Analysis of the facial biotype can provide useful information for orthodontic diagnosis and can determine the type of growth of a patient to guide orthodontic treatment. The objective of this study was to determine the concordance of the facial biotype according to Bjork-Jarabak cephalometric analysis and photographic analysis of the angle of facial opening in Peruvian individuals. MATERIAL AND METHODS: This retrospective study included 244 cephalometric radiographs and frontal photographs of the same patients obtained from a database. The facial biotype (mesofacial, brachyfacial, or dolichofacial) was determined with the Björk-Jarabak polygon (cephalometric) and the angle of facial opening (photographic). Two trained investigators performed all the measurements. The concordance of the facial diagnosis was determined using correlations of the interclass coefficient and the kappa test. p<0.05 RESULTS: In cases with a mesofacial biotype, both analyses coincided in 60 individuals (68.2%), while in those diagnosed with a dolichofacial biotype, the analyses only coincided in 17 individuals (10.4%). There was no concordance between the two methods regarding the brachyfacial biotype since according to the angle of facial opening none of the individuals presented a brachyfacial biotype (kappa weighted test= 0.020, p=0.586). CONCLUSIONS: Cephalometric and photographic analyses should be complementary and one should not substitute the other. Attention should be focused on dolichofacial and brachyfacial biotypes, which showed less concordance between evaluations. So, more studies are needed to follow this line of research. Key words:Facial biotype, cephalometry, photography, facial type, radiography.