General principle Dr. Ahmed AL-Mayali B.D.S M.Sc. Orth. [email protected].
-
Upload
gervase-blair -
Category
Documents
-
view
214 -
download
0
Transcript of General principle Dr. Ahmed AL-Mayali B.D.S M.Sc. Orth. [email protected].
TYPES OF ORTHODONTIC APPLIANCE1-Removable appliance
2-Fixed appliance
3-Myofunctional appliance
4-Combination between Removable and Fixed appliance
Removable orthodontic appliance
Active componentRetentive componentAcrylic base plateAnchorage
Material in orthodontic appliance
• Pliers• cutter• stainless steel wire • acrylic
Types of pliers •Angle plier•Adam plier
Properties of plier
short blade Large comfortable handleTaper of bladeSharp edges of beaksNo roughnessNot rusted
stainless steel wire
18-8 s.s wire1-ClassificationsoftHardExtra hard
2-Advantage
Does not harm the mouth Does not tarnish Supplied hard or soft Annealed Welded Soldered Once adjusted maintain its displacement Economical
3-Physical properties
FatiqueDeflectionFlexibilityRigidity
4-Mechanical properties of S.S. wire
• F= D *R4/L3• F force• D deflection• R diameter of wire• L length of wire
Tooth movement by removable appliance
TippingRotation less than 90
Orthodontic force
LightIntermittentPressure 25-30 g/cm2
Types of wire bend
•Soft curve•Right angle bend•Acute bend
Art principle of wire bend• Sitting position• Cutting the wire• Wire straight• Non traumatic end• Plier gripping • Area of contact × point of contact• Firm wire gripping• Clean left hand• Marker pen• Avoid notching• Avoid repetition• Don’t go back• Imagination• Follow the anatomy• Parallel to the gum, …….