Abstract: An orthodontic bracket for an orthodontic system has a rear base for being mounted to a tooth and first and second portions extending from the rear base. The first and second portions are spaced apart to provide a slot for positioning an arch wire therein. The first and second portions define a front face with an opening for receiving the arch wire. At least one of the first and second portions includes an adjustable tightening element for adjusting the pressure on the arch wire. An orthodontic bracket system comprises a plurality of brackets for being mounted to the teeth of a patient and at least one inter-bracket adjoining assembly mounted to a pair of adjacent brackets and interposed therebetween. The length of said inter-bracket adjoining assembly is modifiable so as to correspondingly modify the distance between the pair of adjacent brackets.

Abstract: A primitive of a base mesh having at least three base vertices is dynamically tessellated to enable smooth changes in detail of an image rendered on a screen. A respective floating point vertex tessellation value (Fv) is assigned to each base vertex of the base mesh, based on a desired level of detail in the rendered image. For each edge of the primitive: a respective floating point edge tessellation rate (Fe) of the edge is calculated using the respective vertex tessellation values (Fv) of the base vertices terminating the edge. A position of at least one child vertex of the primitive is then calculated using the respective calculated edge tessellation rate (Fe). By this means, child vertices of the primitive can be generated coincident with a parent vertex, and smoothly migrate in response to changing vertex tessellation values of the base vertices of the primitive.