Dr. Ahmed AL-Mayali B.D.S M.Sc. Orth. ahmed.almayali@uokufa.edu.iq General principle Dr. Ahmed AL-Mayali B.D.S M.Sc. Orth. ahmed.almayali@uokufa.edu.iq

Types of orthodontic appliance 1-Removable appliance 2-Fixed appliance 3-Myofunctional appliance 4-Combination between Removable and Fixed appliance

Removable orthodontic appliance Active component Retentive component Acrylic base plate Anchorage

Material in orthodontic appliance Pliers cutter stainless steel wire acrylic

Types of pliers Angle plier Adam plier

Properties of plier short blade Large comfortable handle Taper of blade Sharp edges of beaks No roughness Not rusted

stainless steel wire 18-8 s.s wire 1-Classification soft Hard Extra 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 Fatique Deflection Flexibility Rigidity

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 Tipping Rotation less than 90

Orthodontic force Light Intermittent Pressure 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, …….