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DENT 656 – Orthodontics. Fixed Orthodontic Appliances. Sarandeep Huja huja.1@osu.edu. REMOVABLE Tipping only No control over root movement Pt’s co-operation Hygienic. FIXED Bodily translation Control of root movement Less dependent on pt’s co-op Less hygienic.
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DENT 656 – Orthodontics Fixed Orthodontic Appliances Sarandeep Huja huja.1@osu.edu
REMOVABLE Tipping only No control over root movement Pt’s co-operation Hygienic FIXED Bodily translation Control of root movement Less dependent on pt’s co-op Less hygienic Removable vs. Fixed Appliances
Development of Fixed Orthodontic Appliances • Early fixed appliances • Late 1800s • Edward Angle – E Arch, Pin and Tube, Ribbon and Edgewise • Only subtle modifications to the edgewise design have been made, it remains the mainstay in orthodontics (Begg appliance used in Asia to a limited extent)
Development of Fixed appliances • Standard Edgewise appliance • Early 1900s
Development of Fixed appliances • Pre-adjusted edgewise appliance • 1970s • Refined manufacturing process with “built-in” adjustments specific for each tooth • Advances in material sciences made attachment much smaller • Increased efficiency with pre-adjusted appliances
Lingual orthodontics Edgewise slot Must do indirect bonding Decreased interbracket span
Ceramic Appliances - Esthetics Adult treatment
Self Ligating Appliance Brands: Damon, Speed
Components of the Fixed Appliance • Bands • Molar Tubes • Brackets • Arch Wires • Auxiliaries: Elastomeric products, Coil springs, Lingual arches, Extra-oral appliances
Posterior attachments • MOLAR TUBES Triple vs. Double Tubes
Anterior Attachments • Brackets
Arch Wires • Maxillary and mandibular • Arch form described as “parabolic shaped” • Size and cross-section of wires vary • Material varies e.g. Nickel Titanium alloy (NiTi), Titanium Molybdenum Alloy (TMA), Stainless Steel
Elastics Different si CL II Cl III Vertical Latex (allergy’s Different sizes (thickness and dimension)
Elastics Midline elastics Variety of directions
Coil Spring Closed or open coil springs
Pre-Adjusted Edgewise Appliance or The Straight Wire Appliance • Larry Andrews - studied normal occlusion and individual tooth positions • Developed prescriptions for individual tooth position • Elements of “ideal” tooth position are built into the appliance • Minimizing active “wire manipulation” - The Straight Wire Concept
Pre-adjusted edgewise appliance • First order / in-out - Horizontal plane • Second order / tip - Mesio-distal angulation • Third order / torque - Labio-lingual angulation • 3 - Dimensional control of tooth position
4 Second order or Tip
4 Third order or Torque To “Torque” is the least efficient tooth movement using orthodontic appliances
Significance of accurate bracket/band positioning • Precise tooth positioning • Optimal effect of “pre-adjustment” • Occlusion • Esthetics • Stability