Passive Self-Ligating Brackets
The design of brackets utilized in the Damon System. These low-profile brackets are characterized by the absence of the need for auxiliary A-lastics and steel ties (as in conventional brackets) or clips within the brackets (as in active self-ligating brackets) to hold the archwire in place. The archwire in a passive self-ligating bracket is held in place by a labial sliding mechanism. The archwire is, therefore, not bound against the base of the bracket, and friction is minimized. The lumen of the slot is effectively larger, allowing the archwire to freely correct rotations as well as level and align well within the biological limits. The resultant effect is to provide the greater movement with less force applied. By taking advantage of this unique feature, the goal is to apply biologic forces to the teeth that do not negatively impact the vascular supply in the periodontal membrane. In conventional or active self-ligating bracket system the resultant binding and friction forces the clinician to use higher forces which make it more challenging to stay in the Biozone or Optimal Force Zone. By not needing to routinely change bracket ties appointment intervals can be safely expanded.
Taking for "Use what the body gives you to work with." The Damon light force System allows the evident forces to dictate the ideal physiological arch form. By balancing the forces of the lips, cheeks, facial muscles, alveolar and skeletal bone, tongue, periodontal membrane and tooth morphology the operator can retreat from those mechanics which are artificially influenced. Posterior expansion can be achieved without the use of mechanical expanders by adapting these forces, as can leveling, aligning and bite opening. By not overpowering the biomechanical system the body's own physiology sets the course to a more biologically adaptive and biologically normalized result which is patient specific.
A stainless steel (as opposed to Ni-Ti) coil is used for space closure. They are attached to the mesial hook of the posted .019 x .025 archwire and extended distal to the first molar. These deliver a greater force than Ni-Ti coils and are typically used in adult cases as well as those cases where the space desired to be closed has been evident for long periods of time (previous extraction spaces). All other mechanics are identical for space closure.
These are used during the major mechanics and finishing phases of archwire sequencing. (See archwire sequencing) These are .019 x .025 in size and are manufactured of either stainless steel or TMA. The posts can come pre-welded from the manufacturer or can be crimped-on mesial to the cuspid by the operator. The posts are used for space closure with coils springs, for space maintenance following space closure using tieback modules, and for interarch elastics.
Posterior Expansion or Adaptation
The impact of the orofacial muscles on alignment and arch development. By balancing these forces the expansion of the arch is of a posterior nature which alleviates crowding through a balance of the delivery system, blood supply, and muscles. This phenomenon allows the operator to treat non-extraction cases without the flaring of anterior teeth or forcing these anterior teeth through the cortical bone as previously associated with aggressive non-extraction techniques. Anterior-posterior positions of the anterior teeth stay stable while a noticeable and measurable posterior adaptation of the buccal segments. This phenomenon is very similar to the observed "Frankel effect" generated by the Frankel appliance.(These adaptive changes have been shown to be as stable as other types of treatment involving extraction therapy) The clinical impact of this routine clinical observation allows for far more cases being treated with Face Driven Treatment Planning.