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DENT 656 – Orthodontics. Removable and myofunctional appliances. Sarandeep Huja huja.1@osu.edu. Topics. Removable Appliances Including retainers Myofunctional Appliances - Including Head Gear Removable-Fixed Appliance (aka Passive Fixed). Development of Removable Appliances.
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DENT 656 – Orthodontics Removable and myofunctional appliances Sarandeep Huja huja.1@osu.edu
Topics • Removable Appliances • Including retainers • Myofunctional Appliances - Including Head Gear • Removable-Fixed Appliance (aka Passive Fixed)
Development of Removable Appliances • US - Jackson, Crozat • Europe – Andresen, Haupl, Schwartz • Dichoctomy existed till 1970’s • Primary use • Growth modification • Limited tooth movements, tipping – no bodily control • Retention
Removable appliances • Used to expand arches (usually maxilla, not mandible). • Open jackscrew 0.25 mm (1/4 turn), not exceed 1mm/month • Fingersprings – more gentle movement than jackscrew • Retention of removable appliances is critical (anchorage) • Main use today is as retainers, biteplates for crossbite corrections • Some functional appliances are used, but claims of early 70’s not substantiated in randomized clincial trials
Components • Retentive • Active
Components C Clasp and Labial Bow
Active component Fingerspring
Bite Plate Correction of deep bite
Removable Appliances Lower arch expansion Distalizing molars
Retainers used post-fixed appliances • They are usually removable • Can be fixed
Hawley appliance * Labial bow, Adams or C clasp
Tooth positioner Invisalign
Myofunctional appliances History Theoretical Basis
Activator/Bionator* Cl II malocclusions Developed in Europe Dental and skeletal effects
Activator/Headgear Combination Hybrid appliance, add what you need Lip bumper Torquing wires
Frankel Appliance Buccal shields Lip pads Lingual plate
Herbst Appliance Commonly used Has dental and skeletal effects Patient compliance not required
Active Vertical Corrector and Twin Block Repelling magnets Postures mandible forward
Headgear Myofunctional Anchorage for fixed appliances
Headgear Cervical pull High pull
Headgear* – Combi pull and J Hook Usually HG facebow attached to molar tubes J hook directly to soldered hooks on archwire
Face Mask or Reverse Pull HG Used in maxillary deficient cases Cl III due to retrognathic maxillas
Fixed Removable Appliances • Aka Fixed Passive
Upper Hyrax* and Lower Expansion* Upper appliance used prior to age ~ 13, before the midpalatal suture gets interdigitated, get skeletal effects Lower arch – only tipping movement of teeth
Palatal and Lingual Arch* Very commonly used to reinforce anchorage with fixed appliance; 036 SS wire Connects the transverse dimension, and helps in expansion and root movements
Quad Helix* with Finger Springs and W arch Expansion appliances Maxillary expansion more common than mandibular Increase in length of wire by forming helices, 040 wire
Pendulum appliance Bonded to premolars Uses TMA wire with helices molar tubes Anchorage from palate Primarily molar movement, but Movement of anteriors
Habit appliance* Tongue or digit habit