RESUMO
OBJECTIVE: The aim of this study was to evaluate the mean rotation of the upper first molar (U1(st) M) in cast models from nontreated patients presenting: Class I, skeletal Class II, dental Class II, and skeletal Class III, comparing with Class I orthodontically treated patients. MATERIALS AND METHODS: One hundred cast models were evaluated with five groups, composed of nontreated Class I (n = 20), dental Class II (n = 20), skeletal Class II (n = 20), skeletal Class III (n = 20), and treated Class I (n = 20). Measurements were taken from photocopies of the upper arches. The angle formed between a line crossing the mesiopalatal and the distal-buccalcusps of the U1(st) M and a line traced on mid palatal junction were measured in all samples. RESULTS: One-way variance analysis showed that dental Class II group presented great mean rotation of the 1(st) molar (x = 78.95°, SD = 6.19) (P < 0.05), and in 85% of the patients from this group this angle was higher than 73°. CONCLUSIONS: The skeletal Class II and skeletal Class III groups showed similar mean position of the 1(st) molar, presenting rotation in approximately 50% of the patients. It can be concluded that upper molar rotation occurs mainly in dental Class II patients and shows higher mesial rotation angle.
RESUMO
OBJECTIVE: To analyze a possible correlation between different measures in the definition of vertical facial types. MATERIALS AND METHODS: This is an analytical observational study about 95 lateral teleradiographs of Caucasian individuals with normal occlusion, of which 54 were male (56.84%) and 41 female (43.16%), aged between 15 years and 2 months old and 21 years and 4 months old. Facial types were divided into dolichofacial, mesofacial, and brachyfacial, according to the standards established by different authors. A relationship between these measurements was verified using total agreement analysis and the Kappa method, with the interpretation suggested by Landis and Koch. RESULTS: Kappa was considered fair for Jarabak X VERT (0.22 and 60%) and slight for Jarabak X SN. GoGn (0.06 and 36.8%). CONCLUSIONS: Cephalometric studies often present different interpretations on the description of vertical facial types. In this study, the lowest agreement was between Jarabak and SN.GoGn. Such difference in interpretation may lead to distinct therapeutic approaches and thus different results.