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The treatment of skeletal disharmonies presents better results when performed during the growth period. The physical changes that occur in every individual express growth, which is ruled by genetic, general and environmental factors. In order to identify such disharmonies and hence concentrate the clinical actions during treatment and influence facial growth, cephalometrics appears as a useful a diagnostic tool for identifying facial growth patterns or growth direction. Jarabak's cephalometric analysis is used to assess facial growth pattern of subjects with normal occlusion or malocclusions. The purpose of this study was to obtain mean values for cephalometric measurements from Jarabak's cephalometric analyses of black Brazilian subjects resident in the city of Piracicaba, São Paulo state, Brazil and vicinities, who presented Class I molar relationship with normal overjet and overbite, mild or no tooth crowding or spacing, and no history of orthodontic treatment. A sample of 37 stone plaster casts and 37 lateral teleradiographs from both male and female individuals aged 10 to 14 years was evaluated. Data were analyzed statistically by Student's t-test at 5% significance level. There was no significant differences between genders. The cephalometric measurements obtained in this study were similar to the Jarabak's standards, except for S-N mean value in females (66.50 mm +/- 3.16), which was significantly lower than the standard.

The purpose of this study was to evaluate in vitro the shear bond strength of recycled orthodontic brackets. S2C-03Z brackets (Dental Morelli, Brazil) were bonded to the buccal surfaces of 50 extracted human premolars using Concise Orthodontic chemically cured composite resin (3M, USA). The teeth were randomly assigned to 5 groups (n=10), as follows. In group I (control), the bonded brackets remained attached until shear testing (i.e., no debonding/rebonding). In groups II, III and IV, the bonded brackets were detached and rebonded after recycling by 90-microm particle aluminum oxide blasting, silicon carbide stone grinding or an industrial process at a specialized contractor company (Abzil-Lancer, Brazil), respectively. In group V, the bonded brackets were removed and new brackets were bonded to the enamel surface. Shear bond strength was tested in an Instron machine at a crosshead speed of 0.5 mm/min. Data were analyzed statistically by ANOVA and Tukey's test at 5% significance level. There was no statistically significant difference (p>0.05) between the control brackets (0.52 kgf/mm2), brackets recycled by aluminum oxide blasting (0.34 kgf/mm2) and new brackets attached to previously bonded teeth (0.43 kgf/mm2). Brackets recycled by the specialized company (0.28 kgf/mm2) and those recycled by silicon carbide stone grinding (0.14 kgf/mm2) showed the lowest shear strength means and differed statistically from control brackets (0.52 kgf/mm2) (p<0.05). In conclusion, the outcomes of this study showed that bracket recycling using 90-microm aluminum oxide particle air-abrasion was efficient and technically simple, and might provide cost reduction for orthodontists and patients alike.