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Objective: To propose a semi-automated method for pattern classification to predict individuals' stage of growth based on morphologic characteristics that are described in the modified cervical vertebral maturation (CVM) method of Baccetti et al. Materials and Methods: A total of 188 lateral cephalograms were collected, digitized, evaluated manually, and grouped into cervical stages by two expert examiners. Landmarks were located on each image and measured. Three pattern classifiers based on the Naïve Bayes algorithm were built and assessed using a software program. The classifier with the greatest accuracy according to the weighted kappa test was considered best. Results: The classifier showed a weighted kappa coefficient of 0.861 6 0.020. If an adjacent estimated pre-stage or poststage value was taken to be acceptable, the classifier would show a weighted kappa coefficient of 0.992 6 0.019. Conclusion: Results from this study show that the proposed semi-automated pattern classification method can help orthodontists identify the stage of CVM. However, additional studies are needed before this semi-automated classification method for CVM assessment can be implemented in clinical practice. (Angle Orthod. 2012;82:658-662.)

Effective orthodontic anchorage may be obtained by miniimplants inserted into the maxillary bones. However, the risk of miniimplant failure is one of the most important issues, especially the rupture of its structure referred to as fracture, mainly due to metal deficiencies. This study analyzed the internal microstructure of orthodontic mini-implants, ascertaining the composition of the metal to detect possible discontinuities from the surface to the core of the screws. Eighteen samples of mini-implants, of 3 different brands, were obtained. The samples were cold-embedded in methyl methacrylate polymer, and were sectioned both longitudinally (3 samples of each brand) and transversely (the other 3 screws of each brand). After preparation, the samples were observed using a light microscope at up to 2,000 x magnification. The results showed that the mini-implants thus analyzed were composed of an Alpha-Beta globular phase of titanium alloy, patterns A1 and A9 (in accordance with the "Technical Committee of European Titanium Producers"). The miniimplants did not present any defects such as bubbles, imperfections or fissures, in either longitudinal or transverse sections, in their internal microstructure. All samples met the requirements of international norms. Orthodontists must be aware of the metal composition and internal microstructure of mini-implants, to decrease the risk of fractures.

ObjectiveThe objective of this study was to compare the skeletal, dental and soft tissue characteristics of Caucasian and Afro-Caucasian Brazilian subjects with normal occlusion and to evaluate sexual dimorphism within the groups.Material and MethodsThe sample comprised lateral cephalograms of untreated normal occlusion subjects, divided into 2 groups. Group 1 included 40 Caucasian subjects (20 of each sex), with a mean age of 13.02 years; group 2 included 40 Afro-Caucasian subjects (20 of each sex), with a mean age of 13.02 years. Groups 1 and 2 and males and females within each group were compared with t tests.ResultsAfro-Caucasian subjects presented greater maxillary protrusion, smaller upper anterior face height and lower posterior face height, larger upper posterior face height, greater maxillary and mandibular dentoalveolar protrusion as well as soft tissue protrusion than Caucasian subjects. The Afro-Caucasian female subjects had less mandibular protrusion and smaller total posterior facial height and upper posterior facial height than males.ConclusionsBrazilian Afro-Caucasian subjects have greater dentoalveolar and soft tissue protrusion than Brazilian Caucasian subjects, with slight sexual dimorphism in some variables.

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