Fixed appliances

Development of orthodontics in china Removable Begg Edgewise Straightwire (pre-adjusted)

Bracket Metal Ceramic Plastic

Disadvantages of ceramic brackets The bond is too strong Brittle Too hard High friction

Band (1) Buccal and often lingual attachments are soldered or welded. (2) Piror to placement of a band it may be necessary to separate the adjacent tooth contacts. (3) There are different sizes of bands for different sizes of molar. (4) Glass ionomer cement is used for band cementation.

Archwires Stainless steel wire NiTi wire Mutistrand wire

Round wire: 0.014”,16”,18” Rectangular wire:0.016”x0.022”,et al.

Sequence From thin to thick From NiTi to stainless steel From round to rectangular

First-order bends: horizontal plane Second-order bends: vertical plane Third-order bends: torque

Orthodontic adhesives Band cement: glass ionomer, zinc phosphate Bonding adhesive: chemical-cured, light-cured

Chemical-cured adhesive One-paste Two-paste

A set of bonding adhesive Paste A Paste B Sealant A Sealant B Etching solution

Bonding procedure Clean the teeth Etch the teeth paint the sealant mixture paint the paste mixture place the brackets

Auxiliaries Ligatures:steel or elastic Elastic bands:1/8”, 3/16”, 1/4”, 5/16” Elastic chains:close, open, wide The others:expansion screw, headgear, etc.

Typical treatment procedure Aligning and leveling Space closure and correction of occlusal relationship Finishing Retention