Biomechanically and Periodontally-Based Orthodontic Treatment of a Patient with Upper Canine Affected by External Cervical Resorption (ECR): A Case Report.

(1) Background: Orthodontic treatment may be a potential predisposing factor for ECR. The affected tooth goes to ankylosis, which could lead to a malocclusion. Although teeth severely affected by ECR (class IV Heithersay) are usually extracted, this case report aims to present the use of an ECR class IV upper canine, both as ankylosed to solve the malocclusion and the occlusal plane canting, as well as not ankylosed to correct its ridge defect with orthodontic extrusion.

The six geometries revisited.

Forces and moments delivered by a straight wire connecting two orthodontic brackets are statically indeterminate and cannot be estimated using the classical equations of static equilibrium. To identify the mechanics of such two-bracket systems, Burstone and Koenig used the principles of linear beam theory to estimate the resulting force systems. In the original publication, however, it remains unclear how the force systems were calculated because no reference or computational details on the underlying principles have been provided.

Molar uprighting with mini screws: comparison among different systems and relative biomechanical analysis.

Starting from a segmented approach, the Authors propose 3 different methods of using mini screws during the process of molar uprighting. The first UPG is performed by placing a mini screw in the retromolar area and by applying an elastic chain loaded between the screw and the molar.The second UPG is made by placing a screw in the retro molar area and by using a small cantilever which is active during intrusion and uprighting.

The Bracketless Fixed Orthodontics: nine years of clinical experimentation.

The Bracketless Fixed Orthodontics (BFO) is an innovative appliance made up of wires and resin. It comes from the observation of the instable position of frontal teeth still bonded to a fixed retainer and from a period of nine year of clinical experimentation on a way to preactivate a wire to obtain a wished dental movements without brackets. For this historical reasons the first experimental name was: Preactivated Retainers.