tip edge orthodontics;origina
TRANSCRIPT
Tip edge technique
Contents Introduction Tip edge concept Tip edge brackets Tip edge auxiliaries Differential Straight Arch Technique Stages of treatment Final Finishing Conclusion References
Introduction
Since the 1900 Angle introduced various appliances :
Angle’s E-arch Pin and Tube appliance(1910) Ribbon arch appliance (1915) Edgewise appliance(1925)
Edgewise appliance
Labially facing horizontal slot 3-dimensional control over tooth Very high forces were used Anchorage depends on extra oral forces No provision for closure of posterior spaces Arch wire slot restricts the anteroposterior
correction of dental arches
During the early 1930s, P.R Begg reverted to the use of ribbon arch brackets-
Permitted free tipping followed by controlled uprighting Use of round wires Use of differential forces(2 oz) Demands on anchorage units was reduced However the vertically facing slot had the following
limitations: Hindrance in manipulation Reduced mesio-distal control
Begg appliance
Straight wire appliance
1970s Dr Lawrence Andrews introduced the Straight Wire “bracket system”
Concept of Preadjusted appliance-
Tip, torque, in-out compensations for each tooth was available.
Limitations of conventional Straight Wire bracket Moving teeth apex first generates maximum
anchorage resistance Torque control - unwanted reciprocal torque reaction in
adjacent teeth Full expression of torque not achieved- “torque slop”
due to play between bracket and arch wire
Tip edge concept
Peter C Kesling decided to combine both the techniques
Modified a straight wire bracket ,to create Tip Edge bracket
Technique was first introduced at the Kesling-Rocke Orthodontic Centre,Westville,Indiana,USA in 1986.
Differential force technique: initial crown tipping followed by controlled root uprighting with straight arch wires (differential tooth movement with straight arch wires). Therefore it is known as the “Differential straight arch technique”
Arch wire slot permits initial crown tipping mesially or distally and faces horizontally, the slot and bracket are termed “Tip Edge”
Features of tip edge appliance Labially facing arch wire slots –improved
manipulation with elastomeric ties Light forces(2 oz) Reduced strain on anchorage With a rectangular slot ,a 3-D control was afforded Slots open and close during treatment for maximum
ease of arch wire change and minimal discomfort Facilitated intrusion of teeth.
Tip edge brackets
Kesling determined that : It is necessary for each tooth to tip
either mesially or distally –not both directions
All teeth tip distally except those distal to the extraction sites-which tip mesially
Anchor molars should remain upright throughout Rx.
Diagonally opposite corner were removed Permits desired distal crown
tipping Preadjusted in 3 dimensions-
tip,torque,in & out built in Slot size-0.022”x0.028”
Central ridge
Uprighting surface
Lateral extensions
Profile view Occlusal view
Tipping surface
Design features Slot size: 0.022”X0.028” Vertical slot: 0.020”x0.020”- to accept rotating or
up righting springs, power pins ,jigs etc. Both the gingival and incisal ends are chamfered to facilitate the insertion of auxiliaries from either direction.
Lateral extensions- for rotational control hidden behind the arch wire –which is esthetic.
In and out compensation-eliminates the need for lateral, bicuspid or molar offset
Torque built in base Tip built in face
Slot permits initial M-D tipping ,this prevents bowing of arch wire during retraction/space closure and automatically enhances anchorage.
Uprighting surfaces of the slot determine the final tip angulations reached with an uprighting spring. These surfaces can also control torque if an edgewise arch wire is used.
Types of bracket
Narrow metal tip edge bracket
Twin metal tip edge bracket
Narrow ceramic tip edge bracket
Twin version of bracket - 018” or 022” slot size
Known as “Freedom brackets” Disadvantages :
Unaesthetic
Extra bulk-occlusal interferences and accidental
debonds
Mechanical disadvantage when Side Winder springs
are added
Tip edge brackets for first premolar extraction cases
Tip edge brackets for second premolar extraction cases
Tip edge brackets for non extraction or first molar extraction cases
Preadjusted in 3 dimensions-
tip,torque,in & out built in
Tip and torque values for maxillary brackets
Tip and torque values for mandibular brackets
Placement of tip edge attachments Positioning jigs used for bracket placement
Positioning jigs used for bracket placement
Mid crown position is recommended (Parkhouse)
Bracket should be aligned with it’s vertical axis parallel with the long axis of the tooth
Mesio-distally at the midpoint
Height of the bracket should be at vertical midpoint of the fully erupted clinical crown
Jigs can be modified by cutting off the horizontal section leaving only straight vertical markers
Rationale behind a mid crown bonding
Prescribed torque value in the bracket base is effectively expressed
Initial tipping will be more by the incisal placement of the bracket but it also requires an increased amount of root uprighting
Side Winder springs are placed at greater mechanical disadvantage if the distance between the point of rotation and the root apex is increased—resulting in loss of eficiency
Also mid-crown position reduces occlusal interference therefore decreases the number of accidental debonds
Molar tubes Parallel to occlusal surfaces Upper molar tubes placed at the same level as
the bicuspid
Universal premolar tip edge brackets
Similar tip and torque for 1st and 2nd premolars
So, possible to have just 2 upper and 2 lower bicuspid brackets.
Can be switched from R to L side to provide clockwise or counterclockwise crown tipping.
Identification of brackets Arrow - direction of tipping Premolar jigs are modified
by the addition of a 90° angle at the tip of the jig which indicates the direction of tipping
Origin from Queen’s University ,Belfast –called as “Irish jigs”
Auxiliaries used in Tip Edge Technique1.Molar tubes Keep molars upright and permit free sliding of arch wire.
Three types: Single round tube with torquing flap Combination edgewise(0.022”X0.028”) and round
tubes(0.036”) Combination edgewise and flat oval tube for increased
bucco-lingual control
Single round tube with torquing flap Combination of rectangular and round tube
Combination of rectangular and oval tube
Rectangular slot is at the same level as premolar brackets.
Permits the placement of straight arch wire Round tube dimensions:
0.036”inside diameter,0.250”length
Rectangular tubes are of Easy-Out R TP design with the posterior inner lumen slightly flared towards the occlusal. Facilitates archwire removal when a cinchback has been used
2.Tip edge rings Elastomeric rings designed
to function with tip-edge brackets
Designed to retain archwire and prevent mesial and distal tipping during Stage III
Lingually facing lug on either end of the crossbar wedge between the archwire and the bracket to control mesiodistal inclination of the tooth
Straight Shooter (ligature gun)
Advantages
Less time consuming
Places less pressure on the tooth ,more comfortable for the patient
3.Rotating Springs For correction of
rotation Preformed from 0.014”
ss wire Inserted from gingival
aspect
4.Mesiodistal uprighting springs
Optimal means to upright teeth mesiodistally
Standard and Side-winder designs
Provides localised tip control of individual teeth without archwire modification
Fabricated from 0.014” ss archwire
Side-winder springs Coils rest on the labial
surface of the bracket Improves:
Esthetics Hygiene Choice to insert from
gingival or occlusal aspect Mechanical advantages as
centre of the coil is concentric with the centre of the bracket
Invisible Side Winder springs
Wire of spring lies on archwire and bracket
Advantages: Retained in position by the
elastomeric module, in addition to it’s own spring pressure
Enables modules to be changed if necessary, during the root uprighting process without removing springs
Because bulky hook has been eliminated, spring arm has a wide range of activation
Direction of insertion Occlusal and not gingival Masticatory forces coming occlusally are deflected
harmlessly off the coils of a correctly inserted spring, keeping these in close proximity to the bracket face.
If inserted from gingival, occlusal forces might distort them labially away from the bracket –spoils the action of the spring as well as causes discomfort
Identification of spring Spring arm points in the
direction towards which the occlusal tip will rotate
5.Bilevel pins Used to capture auxiliaries
behind tie wings of the bracket
Heads of pins function to retain the auxiliaries and to tie ligature
When used with open coil spring; eliminates the need to use vertical loops or to remove main wire to remove coil
6.Power pins Ideal auxiliaries to engage
elastic or elastomeric Can be inserted from
occlusal or gingival Low profile head with 15°
inclination reducing the need for right and left pins
Can be inserted or removed while both ligature and archwires are in place
7.E-links Elastomeric links
stamped from thermoset material
Less hydrophilic than thermoplastic material
Available in graded lengths
E1to E4 smaller size with no tabs
E4 to larger sizes with tabs
8.Archwires U/L 0.016” round ,hard,resillient wires Vertical loops may be bent into the initial wire Small segment of co-axial wire 0.014” or 0.016” NiTi as auxiliary wires for alignment Advantages:
Rapid anterior bite opening and improve molar control Reduces the number of archwires required to treat a
specific case
0.022” SS used during space closure and final uprighting or torquing
Rectangular archwires retained in brackets with tip-edge rings offer the final expression of tip and torque predetermined in the bracket slot
0.0215”X0.028” SS archwire are preferred for final finishing
Concept & Function
Bite opening Tip-edge slots facilitate intrusion of teeth along the path
of least resistance without creating lateral root movements—open deep bites without the need for extra oral forces
Intrusive forces from: Properly bent 0.016” high-tensile SS wires,
Use of Light inter maxillary elastics(2oz).
Retraction and Space closure without loss of vertical control
Binding between slot and archwire In the canine area incisal deflection of
wire
No binding or incisal deflection of wire in tip edge slot
Dynamic arch wire slot
Tip edge slots become larger as the teeth tip. The vertical dimension within the slot continuously increases with each degree of distal tipping.
Inter bracket distance The tip edge bracket
provides automatic mesiodistal tip control
The tip edge bracket with its propeller shaped archwire slot can provide 100% interbracket distance in both planes.
As the crown is tipped distally, slot size increases, this permits passive engagement of full size SS wire with zero flexing.
Advantages No binding or archwire deflection during retraction Ease of stepping up of archwire size No inadvertent mesial or distal root movement Ease of placing rectangular archwires when third
order discrepancies exist between archwire and slot. No need to use NiTi archwires to avoid discomfort
and accidental debonding
“The Hammock Effect”When a ligature (especially
steel) is used to retain the archwire a “hammock effect” is created that tends to parallel the archwire with the gingival and occlusal edges of the tie wing tips.
This could influence mesial /distal inclinations
Steel ligature when tied loosely minimizes the hammock effect.
Anchorage consideration Extra oral anchorage is not required with Differential
Straight Arch Technique Forces are so light that adequate anchorage can easily
be formed within the mouth. Binding (as in edgewise slots) is nonexistent during
retraction. In DSAT,archwires move distally with anterior teeth
retraction and premolars are not bracketed during Stage I. Therefore no sliding friction occurs---no additional strain on anchorage.
Only friction is in molar tubes which is minimal because tubes are long with large diameter.
Axial inclination control
Controlled root movement which is Selective Physiologic Predetermined
Selectivity Selective axial tooth control w.r.t time and location Tip or torque is achieved by addition of Side-
Winder springs to the teeth requiring correction Rest of the teeth are left undisturbed Application of force is selective and adjacent teeth
are not “round tripped” Promotes stability and patient comfort
Limitation Design of the bracket automatically limits the
degree of M-D uprighting Uprighting continues until the control surfaces
within the slot strike the upper and lower surfaces of the archwire.
Torquing is also limited and ceases even though the spring remains active-determined by the torque built in the bracket
Physiologic Light and continuous forces are transmitted
through the auxiliaries Design of tip edge bracket prevents delivery of
high third order torque forces from flexed rectangular wire
Advantages of Tip Edge brackets
Over conventional edgewise brackets Eliminates undesired force couples to promote rapid
bite opening and prevent midline discrepancies Anchorage problems are eliminated as space can be
closed with light forces and minimum wire deflection. This results in diminished anchorage demands and increased vertical control.
Permits free crown tipping followed by controlled uprighting
Can reposition teeth and jaws with light forces and still maintain total control over their final positions.
Over Begg brackets Horizontally facing archwire slots facilitate initial archwire
engagement especially on rotated teeth. Elastomeric ties provide a cushion or flexibility that enhances patient comfort and reduces the chances for bond failure
In –out compensation eliminate the need for molar (or other) offsets.
Slot designs causes automotive shift from tipping to bodily movement at the predetermined angle and increase anterior anchorage to encourage mesial movement of posteriors –
“Programmed Differential Mechanics” Labio-lingual root torque from rectangular wires possible.
Three stage of Treatment
Stage I Objectives
Open (or close) the anterior bite Eliminate anterior crowding Close the anterior spaces Overcorrect the rotated cuspids and bicuspids Correct posterior cross bites Correct any mesiodistal malrelationships of the
buccal segment as necessary
Stage I archwires 0.016 S-S wire Preformed wires
Fabricated from 0.016” Bow flex archwires
These are size graded according to the distance in mm between the cuspid circles
Intermaxillary circles Bent in a vertical plane or inclined slightly labial located 1mm mesial to canine bracket Anterior portion of the circle is labial to the archwire to facilitate
engagement of distally directed ties or elastics
Advantages of cuspid circles: Easier to bend Can be rolled mesio-distally Less chance of breakageDisadvantage: Less retention of elastic if bent too small or tightly
Cuspid ties Prevents canine from
sliding distally along the wire
Not to be used when aligning crowded anterior teeth with co-axial or NiTi sectional wire
Bite opening mechanics Anchor bends placed 2 mm mesial to molars If reduced overbite or an open bite is present at
the start of the treatment, reduced degree of anchor bends are placed.
Also depends upon the angulation of molars-if molars are tipped mesially, reduced angulation required.
Intermaxillary elastics Use of light Class II elastics (1 to 2 oz)
Worn full time from upper cuspid circles to the distal ends of lower arch wire or from molar hooks
Overbite reduction is more effective with a more distal application of elastic to the molar which better resists distal crown tip and encourages fuller expression of the anchor bends to the anterior segment
Outrigger applianceTo encourage elastic wear
Auxiliary is threaded over an archwire formed with appropriate bite opening bends or sweeps but no intermaxillary circles
Has two elastic hooks that extend labially when elastics are not engaged
Hooks act as a painful reminder
Stage II Objectives:1.Close any posterior spaces
2.Maintain all corrections obtained during stage IEdge to edge relationship of anterior teeth
Anterior space closure
Over rotated cuspids and or bicuspids
Corrected mesiodistal molar relationship
Stage II archwires 0.020” or 0.022” hard round S-S wire Reduced anchor bends Molar offset (vertical) to compensate for the more
gingivally placed round tube Heavier archwires function as retainers to maintain
arch form and bite opening achieved during stage I Heavier wires can better withstand the forces of
occlusion-less likely to get distorted
Remove anchor bends, place sweep in the archwire
Upper- increased Curve of Spee
Lower- Reverse Curve of Spee
Insert wire into rectangular tube (Parkhouse)
Derotation of molar 1mm Molar offset and 10°toe-in for final visit of
stage II Initial stages no need to place these bends as it
increases friction
Levelling of molar Tipped back molars should
be leveled to allow the placement of rectangular archwires
Antitip bend of 10° opposite premolar-molar contact point
Ensures seating of the distal cusp of tipped molars
Can be combined with offset and toe-in
Space closure By E-links form buccal
hook on the first molar to cuspid circle
Available in graded lengths
Usually E-6 or E-5 is selected
Putting on the brakes:
Available space can be closed by protraction of the posterior teeth mesially :
a. Application of passive uprighting spring on the canine,
b.Tipping surface of the tip edge arch wire slots striking the archwire
c. Use of rectangular wire
Automatic canine rotational control during retraction Forces are not applied labial to the surface of
canines. Instead pressure is applied at their contact point
with the lateral incisor
Stage II checks Intervals 6-8 weeks Observe space closure Cut distal ends Check molar widths Labial segment position and inclination excessive Check midlines Check interarch-relationship Avoid overcompression
Pre Stage III To align the premolars Rotate anchor molars Level the occlusal plane Original 0.016 round archwire is used Increased flexibility helps to level occlusal plane
and elevate premolars Light lingual elastomerics to derotate molars Duration-- 6-8 weeks
Stage III Objectives:
Maintain all corrections achieved during stage I and stage II
Achieve desired axial inclination of all teethM-D inclinations are corrected by use of uprighting springsLingual or labial root torque is achieved through torquing auxiliary Tip edge rings maintain and/or influence teeth in final tip angulations
Stage III archwires 0.020” or 0.022” hard round S-S
wires- to counteract the reciprocal forces generated by auxiliaries
Heavy wire functions as retainer Separation of root moving forces
from the archwire permits the precise application of torque and uprighting pressures
Maxillary archwire slight constriction is placed in
the archwire (except in RME and class III malocclusion)
No anchor bends but a gentle curve of spee is given to deliver a gingival force
Maxillary archwire
Mandibular archwire Slightly expanded Slight anchor bends or
Reverse curve of spee Vertical offsets to
compensate for the level of molar tube
In class III Rx –widen the maxillary arch and narrow the mandibular
Cuspid ties are normally not used to allow uprighting of teeth to take place.
Mandibular archwire
Stage III Auxiliaries Torquing auxiliary
Conventional torquing auxiliary
Torque bars
Curved ribbon sections of 0.022 X0.028” Ni Ti formed with 20° of torque.
Individual root torquing auxiliary
Nickel titanium torque bar
Individual Root Torquing auxiliary
Deep Groove brackets For use with torque bars On the maxillary central
incisors Conventional preadjusted
edgewise slot cast into the bottom of tip edge slots.
During stage I and II ,cap fills the groove
In stage III,cap is removed and the torque bar is ligated tightly into the Deep groove under the round archwire.
Uprighting with Side Winder springs
Third order movement by second order force from a Side Winder spring in the presence of a rectangular archwire
Indications for rectangular archwires First proposed by Richard Parkhouse Simplifies treatment and increases stability during
all uprighting and torquing procedures To establish molar root torque
Preparation for rectangular Stage III After completing stage I, 0.016” wire is modified with
vertical curvatures instead of anchor bends ,to avoid the use of vertical offset
Wire is inserted into the rectangular tube instead of round tubes. This elevates premolar brackets to the level of rectangular tube
If premolars are too gingival –initially place the wire into round tube, then into rectangular tube.
Once premolars are aligned ,shift to 0.020” or 0.022” round wire
Rectangular stage III wire 0.0215”X0.028”
rectangular archwire with similar curvature as in round wire
Crimpable hooks are placed midway between canine and lateral incisor brackets facing gingivally
Mild Curve of spee in maxillary archwire and RCS in mandibular archwire
If initial open bite or reduced overbite, flat archwires are made
Compensatory buccal crown torque in anterior segment to restore zero torque
Pretorqued archwire 0.0215” X 0.028” rectangular archwire with lingual
crown torque (5° maxillary,8° mandibular) for deep bite cases
Centre line markings:Black—maxillary
Red--mandibular
Round or Rectangular archwires?? Severe anteroposterior discrepancy round wires
for stage III Also when molar torque or selective labiolingual
root positioning of canine or mandibular incisor is not required
Rectangular wires should not be used until the torque has been established by use of torquing auxiliary
Final finishing Use of rectangular wire during this stage Beginning with 0.019”X0.025” ,then 0.021”X0.028” for total
tooth control. Rectangular wires should pass through the rectangular
tube Tip edge rings can maintain or even capture the tip angles
in all bracket slots
All stage III objectives ,especially anterior root torque must be entirely completed before going to rectangular finishing archwires
Second molar alignment During Stage III, preliminary
alignment by a simple sectional device suggested by Dr Tom Rocke.
Straight 0.016”high tensile S-S sectionals
It runs through the channel of the gingival tie wing of the first molar, without being attached to it.
Mesially ends with a small occlusally inclined loop which hooks over the main archwire
Occlusal seating 0.019X0.025” braided
archwire and seating elastics
3 weeks later
Sectioning the main archwire Cut distal to each canine Molars and premolars, canine to canine tied
together to prevent spacing Light rhomboid elastics to allow settling of buccal
section
Tooth Positioners
Pre-Fit positioners come in different sizes (for extraction and non-extraction cases)
Inappropriate for individual tooth size discrepancies
Conclusion The tip edge bracket provides varying degrees of
tooth control not previously available in an edgewise type bracket.
Control ranges from a simple one-point contact and 100% interbracket distance with a round archwire to predetermined control in three planes with rectangular arch wire and a Tip-Edge ring.
It also offers advantages over ribbon-arch (Begg) brackets through ease of manipulation provided by the horizontally facing slot plus predetermined limitation of initial crown tipping and control of final root uprighting.
References
Tip Edge guide and the Differential Straight Arch Technique. Peter C Kesling
Orthodontics by Graber Vanarsdall. Tip Edge Othodontics.Parkhouse Dynamics of the Tip-Edge
bracket.PeterCKesling.AJODO1989;96:16-25 Treatment with Tip-Edge brackets and Differential
tooth movement.KeslingPC,Rocke TR,KeslingCK.AJODO1991;99:387-401
The Tip –Edge Concept:Eliminating Unnecessary Anchorage Strain.Kesling CK.JCO1992;26:165-178.
Thank U