Sunday, November 4, 2007

The Basics

Two of the most important aspects of orthodontic treatment are bracket positioning and arch width control. First, let's discuss bracket positioning.

Bracket Placement Review

A prominent orthodontic educator recently stated that "In the 1960's, the best orthodontics was done by the best wire benders. Today, the best orthodontics is done by the best bracket positioners." I couldn't agree more with this statement.

•Horizontal Positioning of Brackets
Visualize center of tooth directly from the facial surface, then look down long axis of the tooth
May need to use a mirror for bicuspids
Placement errors lead to rotations

•Rotational(axial) errors
Cause unwanted tipping
Keep incisal edge of bracket parallel to incisal edge of tooth
use same visualization techniques as for horizontal placement

•Excess bonding agent under the bracket
may cause rotational errors
To avoid these, push bracket firmly onto tooth

•Vertical errors
Cause excessive extrusion or intrusion
Check the same tooth on the other side of the arch and make sure the inciso-gingival position is the same on both sides- this prevents occlusal plane tipping

•Mesio-distal position
–Position bracket on the mesio-distal center of the tooth for all upper and lower centrals, laterals, and cuspids

-In most cases, position the brackets in the mesio-distal center of all molar and premolar teeth

Inciso-gingival position

•Deep bite patients
–Position brackets 1 to 2 mm incisal to the center of the tooth
•Open bite patients
–Position brackets 1 to 2 mm gingival to the center of the tooth

The pictures on the right show ideal anterior bracket placement for

average bite (top), deep bite (middle), and open bite (bottom).

Occluso-gingival placement of premolars

•Deep bite cases
–Position brackets 1 to 2 mm gingival to the center of the tooth
•Open bite cases
–Position brackets 1 to 2 mm occlusal to the center of the tooth

Upper molar bracket (or band) position
•Anterior portion of bracket bisects the MB cusp
•Final band seat is accomplished with lingual pressure
•Bracket in the occluso-gingival center for all cases

Lower molar bracket (or band) position
•Bracket always placed in the center of tooth
•Final band seat is accomplished with buccal pressure


Ariana said...

Of course you have to know braces positioning. But for being the best orthodontist you must start with the best diagnosis. Appliances are secondary and change as time passes by.

Ligia said...

Very useful! I' m a beginner and these clinical examples were very welcomed.