may 30, 2002 - removable appliances i
TRANSCRIPT
Removable OrthodonticRemovable OrthodonticAppliancesAppliances
Gregory Jackson DDS, MSD Preclinical Orthodontics ORTD 323
May 31, 2002
Removable AppliancesRemovable Appliances
• Advantages & disadvantages• Brief history & development• Major uses of removables
• Growth modification• Limited tooth movement• Retention• Adjuncts to treatment• Mild to moderate malocclusions
AdvantagesAdvantages
• Appealing to patients especially adults• Inexpensive• Easy to make and adjust• Initially less chair time• Allow for some types of growth
guidance
DisadvantagesDisadvantages
• Totally cooperation dependant !!!• Limited to less complex movement• Limited range of movement
Development of RemovablesDevelopment of Removables
• USA- fixed appliances- Edward Angle• Minimal usage of removable appliancesPrecise positioning of teeth
• Europe-removable appliances• Geographic separation • Social welfare systems-limited tx. for masses• Scarcity of precious metals for fixed
appliancesAlterations in function produced by
removables give stable correction of malocclusion
Removables in EuropeRemovables in Europe
• Growth Guidance with Functional Appliances
• Change mandibular posture • Open & forward
• Pressure from stretch of muscle & soft tissues transmitted to teeth & bone
moving teeth and modifying growth
Today Dichotomy DisappearedToday Dichotomy Disappeared
Instantaneous exchange of ideas & info.Politics, economics, travel, electronic age
Can We Grow Mandibles?Can We Grow Mandibles?
Chapt. 8 Contemporary Orthodontics
“An acceleration of (mand) growth often occurs when a functional appliance is used … , but the final size of the mandible is little if any larger than it would have been without treatment.”
Other functional appliance tx. effects:• Mand. teeth forward, max.teeth back- Cl. II el. effect• Restraint of forward growth of maxilla- HG effect
Tooth-borne Functional AppliancesTooth-borne Functional Appliances
• Activator (Andresen)
• Bionator(Balters)
• Herbst
• Twin Block(Clark)
Tissue-borne Functional AppliancesTissue-borne Functional Appliances
Functional Regulator (Frankel)
Limited Tooth MovementLimited Tooth Movement
Appliance Design
• Acrylic plate – stability
• Active portion – force application
• Clasps & occlusal rests- retention
Acrylic PlateAcrylic Plate
Maintenance Plate
•Stabilize•Space maintenance•Replace tooth•Bite Plane•Posterior overlay
Be Creative!Be Creative!
Active PortionActive Portion
• Expansion – screws• Repositioning teeth – springs• Space closing – labial bow & springs
Expansion ScrewsExpansion Screws
SpringsSprings
Anterior Alignment
Anterior Cross-bite Primary DentitionAnterior Cross-bite Primary Dentition
Anterior Cross-bite Mixed DentitionAnterior Cross-bite Mixed Dentition
SpringsSprings
Posterior space regaining
correct incorrect
Spring winding
SpringsSprings
Space Closure
Adjustable Labial BowAdjustable Labial Bow
Clasps & RestsClasps & Rests• Adams
• C
•Occlusal rest
•Ball
•Arrowhead
RetentionRetention
• Hawley• Circumferential• Spring• Invisible – Essix• Positioner
Hawley RetainerHawley Retainer
With or without ant. or post. biteplate
Circumferential RetainerCircumferential Retainer
Spring RetainerSpring Retainer
Invisible Essix RetainerInvisible Essix Retainer
Vacupressureformed
Biostar Machine
PositionerPositioner
Adjuncts to TreatmentAdjuncts to Treatment
Biteplate
Nightguard
Removable Appliances Used in Removable Appliances Used in Mild to Moderate MalocclusionMild to Moderate Malocclusion
More to come