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Aim. To determine whether a relationship exists between the linear measurements of overjet and overbite and the interincisal space delimited by the morphology of the upper and lower incisors. Method and Materials. 30 subjects (age range from 14.1 to 34.8 years, with a median age of 23.5 years and sex ratio F/M: 5/10) with overjet and overbite equal to 2 mm were selected from a group of 381 individuals with a full and well-aligned dentition, no previous dental treatment, and no signs or symptoms indicative of temporomandibular disorder. Computed Tomography images of vinyl polysiloxane impressions of the 30 subjects' anterior teeth were acquired. The interincisal space was defined as Immediate Overjet Angle and was calculated on the Computed Tomography images. Results. Although the 30 subjects presented overlapping measures of overjet and overbite, the values of the Immediate Overjet Angles were different in a range of a minimum value of 12° and a maximum value of 54°. Conclusion. This study reveals that (1) only 30 (7.9%) of the 381 individuals considered have values of overjet and overbite equal to 2 mm and (2) the Immediate Overjet Angle values of the 30 subjects are not related to the values of overjet and overbite.

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Objectives: The finishing of the gingival floor and its margins is regarded to be necessary in Class II cavities, so the aim of this research was to evaluate 4 finishing systems for the cervical margins of Class II cavities, with regard to surface roughness and waviness. Methods: Eighty Class II cavities were prepared in 20 intact molars by a single operator, using a diamond-coated bur (granulometry 80 μm) mounted on a parallelometer, under magnification (5x, Zeiss) in order to reduce variability. In every tooth, 4 different finishing methods were randomly applied: A: carbide bur; B: straight hand chisel; C: diamond-coated bur 60 μm; and D: diamond-coated sonic instrument. After that, the gingival floor of each cavity was analysed with an optical profilometer. Mean surface roughness (Ra) and mean surface waviness (Wa) were evaluated with an optical device. Results were analysed with ANOVA after ln-transformation of data. One- and two-way ANOVA was applied. Results: There was no statistically significant difference between the 4 test groups for Ra which was in the range between 0.76 and 0.92 μm. For Wa, the diamond bur produced significantly lower waviness values (mean Wa 5.2 μm) than the other three instruments (mean Wa between 5.7 and 7.7 μm). The variability of Ra and especially Wa was very high: the coefficient of variation of Ra was between 23% and 38%, that of Wa between 52 and 57%. Conclusions: As there was no difference between the four instruments considering surface morphology, the efficient and safe sonic instruments should be chosen over the other three instruments for finishing proximal boxes of Class II cavities