DR.EDWARD HARTLEY ANGLE
The edgewise arch
mechanism was the brain
child of this master
By the time of
introduction of milled
brackets, S.S ligature
wires it had evolved into a
precision appliance, that
demanded accurate fitting
and placement of bands
and attachments on teeth.
► The edgewise arch mechanism/appliance was
Dr Angle’s last and greatest contribution to
orthodontics ,after almost a lifetime devoted to
improvement of orthodontic appliances.
► Edgewise mechanism was designed to place
teeth into Angle’s concept of line of occlusion:
“the line with which in form and position
according to type, the teeth must be in harmony
if in normal occlusion.”
ANGLE’S PHILOSOPHY OF
Based on the then prevalent assumption that, if cuspal
interdigitation of teeth were made normal, stimulation by
function would result in growth of basal bone structures.
Little or no thought was given to the inclination of the
mandibular incisor teeth or to normal mesiodistal relation of
teeth and their respective jaw bases and head structures.
It was assumed that function would take care of such
Extraction of teeth for orthodontic therapy wasn’t even an
E.H. Angle – Graduation 1878, experienced many
technical problems and frustrations in treatment which
irritated, motivated and inspired him to develop a
standard appliance. His obsession for order motivated
him to create the Angle System (1887)
This ultimately resulted in the multi banded edgewise
appliance 5yrs before his death.
THE STANDARD APPLIANCE
USED BY ANGLE
Basic components of
appliance used by
► Unique feature rectangular wire
rectangular slot twisting / torquing forces
could be imparted to control the axial inclination
► So possible to move teeth in all 3 planes of
space with a single arch wire.
For rectangular wire to move teeth into the “line of occlusion”,
it had to be shaped into normal arch form and given proper
twist or torque for individual teeth.
Angle recommended use of smaller diameter round archwires
in the early stages of treatment.
Repeated tying of the eyelets for rotation.
Necessary to continue tying eyelets throughout treatment
to prevent relapse.
Tying rotation eyelets is time consuming.
2)Twin brackets:- two brackets on one base
-“Siamese twin brackets” by
- space between two brackets
was .050 inch (equal to width
of one bracket )
- Available in different widths:►
4)Lewis bracket:► Developed by Lewis in
► To overcome the problem
of efficient tooth rotation.
► He soldered auxillary
rotation arms that
abutted against the
bracket itself, thus, offered
a lever arm to deflect the
archwire & rotate the tooth.
► One piece bracket with
integral rotation wings
wings do not interfere with
occlusogingival deflections of archwire & do
not decrease the interbracket span
► 100% of the desired tooth rotation is
5)Curved base Lewis bracket:► Curved base confirms to the canine, premolar surface
► Types:- Long
lie close to the tooth throughout their
length ,so less trapping of food
► Increases the surface area
6)Vertical slot Lewis bracket :►
Incorporation of .020 x .020 inch vertical slot
Possible to use uprighting spring to correct axial
inclinations if needed
1) complete rotational control
2) do not reduce the interbracket span
7) Steiner bracket :►
Given by Cecil C Steiner in 1931
Incorporated flexible rotation arms & so did not rely
on the resiliency of the archwire for tooth rotation
Introduced tie wings for ease of ligation
► Easy to tie
► Quite efficient for tooth rotation
► Once permanent deformation of the arms has
occurred, complete rotation will not be effective
unless the arms are adjusted to their original
Designed by Garford Broussard for use in the Broussard
Addition of a 0.0185 x 0.046 inch vertical slot to accept a
doubled 0.018 inch auxillary wire
EVOLUTION OF EDGEWISE
1)Original buccal tube was a piece of .022x .028 inch
gold or nickel silver tubing soldered to the molar band
Length –3/16 or ¼ inch
Buccal tube is for the insertion and stabilisation of the
Notched distal ends - to facilitate a tie back ligature
Hook – gingival to buccal tubes, soldered on the
bands for placement of elastics
Inconel tube - gold buccal tubes were discarded
- is preattatched to the curved and
contoured welding flange.
2)Combination buccal tubes
► Incorporates a round tube for insertion of a face bow
► Posses sufficient rigidity to resist deformation from the
forces of occlusion.
► Fairly close tolerances must be maintained between
archwire & tube for effective transmission of torque to the
3)Triple buccal tube
► additional rectangular tube for auxillary sectional & base
LIGATURE TIE WIRE
► Used to attatch archwire to the bracket.
► Dead soft .009 or .010 inch stainless steel ligature
wire is used.
BRACKET & TUBE
Angle - “goal of correct bracket & tube placement is
to produce an ideal occlusion at the end of treatment
with flat, straight, ideal archwires
Brackets were soldered to band strips with the slot
parallel to the band strip.
General rule was to place band strip with the
brackets parallel to the long axis of the teeth.
Posterior brackets were angulated to produce desired
Holdaway (1952) described three uses for bracket angulation
a) as an aid in paralleling roots adjacent to extraction spaces
b) as a method of setting up posterior anchorage units into tipped back
or anchorage prepared positions
c) as a means of obtaining correct axial inclinations or artistic
Orthodontics Current Principles and Techniques
- Thomas Graber , Robert Vanarsdall
Contemporary Orthodontics - William R. Proffit
Orthodontics Principles and Practice T.M.Graber