Isabela Almeida Shimizu

Princípios biomecânicos do aparelho extrabucal

The use of the headgear appliance for the treatment of Angle Class II malocclusion demands that the biomechanic principles are understood and applied so that the clinic case is conducted in a way that the side effects are minimized and the benefits maximized. Therefore, the orthodontist must be able to predict the effects of the inclination of the line of traction and its relation to the teeth and maxillary centers of resistance. Any rotation movement, inclination or translation of the teeth and maxillary and mandibular rotation clockwise or counter clockwise can be predict and planned when the orthodontist knows the mechanism that cause them, as well as the effects that the different types of traction produce in subjects with dolichofacial, mesofacial or brachyfacial types. Thus, the aim of this work is to present predominant and indispensable factors for the utilization of the headgear appliance for the treatment of Angle Class II malocclusion.

Assessment of shear bond strength of brackets bonded by direct and indirect techniques: an in vitro study

Methods: Thirty healthy human maxillary premolar teeth were used. The teeth were divided into three groups of 10 teeth each: Group I - indirect bonding with Sondhi™ Rapid-Set system (3M/Unitek), Group II - indi- rect bonding with Transbond™ XT adhesive system (3M/Unitek) and Group III - direct bonding with Trans- bond™ XT adhesive system (3M/Unitek). After bonding and obtaining the specimens for the study, the specimens were subjected to SBS testing in a universal testing machine (Emic, model DL-500). The Kolmogorov-Smirnov test was applied to ascertain that the data had a normal distribution and the Bartlett test to check whether there was homogeneity of variance. One-factor analysis of variance was performed and, subsequently, Tukeys test for paired means. A 5% significance level was adopted.