Dental Brackets-Interesting models
Brackets act as handlers to transmit the force from the active components to the teeth.Brackets have one or more slots that accept the arch wire. Brackets can be available in different designs and can be classified in a number of ways.
Edge Type of Bracket
Brackets used in the Edgewise and Straight Wire technique have a horizontal slot facing labially. These brackets with rectangular slots are so called because they accept wires of rectangular cross-section with the larger dimension being horizontal. These brackets provide greater control over tooth movement and do not permit tipping of teeth.
Ribbon Arch Brackets
They are brackets which possess a vertical slot facing the occlusal or gingival direction. This kind of bracket is used with round wires to bring about tipping of teeth in labio-lingual as well as mesio-distal direction. These are used in Begg fixed appliance.
Weldable and Bondable
Weldable brackets can be welded on to bands which in turn are cemented around the teeth and Bondable brackets can be bonded directly over the enamel. The under surface of bondable brackets has a mesh or grooves to help in interlocking with the adhesive while weldable brackets have a metal flange that can be welded to the band.
Steel brackets are most commonly used of this type. The advantages are:
- They can be recycled and sterilized
- They resist deformation and fracture
- They exhibit the least friction at the wire bracket interface
They are made up of aluminium oxides or Zirconium oxides. They are dimensionally stable,durable and resist staining in the oral environment but they are brittle and to compensate, their size is increased which tends to increase their bulk and also exhibit greater friction at the wire bracket compared to metallic brackets.
They are mostly made up of Poly carbonates which are mainly meant to increase the esthetic value and they are available both in coloured or transparent forms. The main disadvantage is the friction between plastic brackets and metal arch wire is very high.