Roth philosophy /certified fixed orthodontic courses by Indian dental academy
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Transcript of Roth philosophy /certified fixed orthodontic courses by Indian dental academy
THE ROTH PHILOSOPHY
INDIAN DENTAL ACADEMY
Leader in continuing dental education www.indiandentalacademy.com
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In 1968, R . H ROTH was introduced to Dr. L.F.
ANDREWS of San Diego
Roth started using straight wire appliance in his practice
in 1970 when Andrews gave him the first set of prototype
brackets that were welded into pinched band material
and had been machined at great expense.
After seeing the treatment progress of the first patient, he
purchased the first commercially available Andrews
brackets and started all his new cases with SWA.
By the mid 1973,he switched his entire practice over to
the SWA and rebonded all the patients who still had
edgewise brackets.www.indiandentalacademy.com
He did extensive work in Andrews SWA and published two articles namely
1.Five year clinical evaluation of Andrews SW appliance.(1976 jco)
2.The SW appliance 17 years later (1987 jco).
He started designing his own prescription as a clinical trial and error evaluation that lasted severed years.
Cases were evaluated by the use of
•Intra oral photograph and
•Mounted models for tooth positions
During treatment and
At the end of appliance therapywww.indiandentalacademy.com
According to him teeth tend to relapse back from which
they started, and if counter-tip, counter-rotation,
counter-torque, and leveling of the curve of Spee were
applied to the SWA in every possible direction, then it
should be possible to use primarily one prescription for
most cases, and to finish to an "END OF APPLIANCE
THERAPY" goal in which all tooth positions are slightly
overcorrected and from which the teeth will most
likely settle into non-orthodontic normal positions
So with the concept of overcorrection he designed his
comprehensive prescription using the available
Andrews extraction brackets. www.indiandentalacademy.com
THE ROTH Rx
In 1979, Roth
introduced a bracket
setup containing
modifications of the tip,
torque, rotations and
in out movement of the
Andrews standard setup
brackets.
Ronald H. Roth
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The major difference between the Andrews philosophy and the Roth approach to the use of the straight wire appliance has to do with the manner in which the teeth are moved and not necessarily the desired end result or the result attained.
ANDREWS attempts to translate teeth throughout treatment without ever tipping teeth. This leads to the necessity of utilizing sliding mechanics and number of different series of brackets to solve the problem of translating teeth depending on how far the teeth must be moved.
In the ROTH approach, tipping of teeth is allowed, by using round wires in the initial phase of the treatment, but the attempt is to keep the tipping to a minimum wherein it is not necessary to resort to complex mechanics to do the uprighting
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Andrews' occlusion study was based purely upon anatomical measurements of tooth positions on untreated normals.
According to him teeth should be positioned from an “ANATOMICAL STANDPOINT’”
Roth’s occlusion study was based purely upon pantographically recorded and mounted a large number of post-treatment orthodontic cases on the Stuart articulator
According to him natural teeth should be positioned from a “GNATHOLOGICAL STANDPOINT”
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Andrews SW appliance…..
Andrews collected 120 Non orthodontic models. He studied these models anatomically and laid down his “six keys to normal occlusion”
I MOLAR RELATION IV ROTATIONS
II CROWN ANGULATION V TIGHT CONTACTS
III CROWN INCLINATION VI CURVE OF SPEE
•After determining the “six keys to normal occlusion” he
made certain measurements in the non orthodontic
models which helped him in the development of SWA
Andrews original standard straight wire brackets were
designed to treat only non extraction cases with an ANB
differential of less than 5º without the necessity of putting
offset bends into the wire.
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Then he introduced the extraction brackets which had
counter tip and counter rotations built in, to allow
translation of teeth as much as possible and to offset any
relapse tendency.
Later he introduced different series and sets of brackets
for different combinations of extractions, and differentials,
and anchorage requirement
He developed a special classification of malocclusion and
prescribed various bracket series for treatment of each, to
allow translation of teeth without the need for bending
offsets and also to allow for over correction in view of
relapse tendencies.www.indiandentalacademy.com
- what made roth to modify Andrews SW appliance
Inventory problem-To treat different cases clinicians were to buy band kits for all Andrews sets and series. They are very extensive inventory on the self. Also, changing anything about the appliances would be prohibitively expensive.
Anchorage loss -When mesially angulated brackets are placed on the posterior teeth, the teeth tend to tip mesially and migrate forward that resulted is anchorage loss.
Problem in finishing - To achieve desired tooth positions with the standard SWA, it was necessary to finish the mechanotherapy phase of treatment by placing compensating and reverse curve in the upper and lower archwire.
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Roth's rationale for his bracket set up.
The purpose of the Roth setup was to provide over
corrected tooth positions prior to appliance removal that
would allow the teeth in most instances to settle to what
was found is non orthodontic normals studied by
Andrews.
•With the appliance in place, it is virtually impossible,
because of bracket interference, to position the teeth
precisely into the occlusion shown by the non orthodontic
normal sample.
•After appliance removal no matter how well treated the
patient may be, the teeth will shift slightly from the
positions they occupied at the time the appliance were
removed
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•Play or tipping freedom - Due to the play between the archwire and bracket, the delivered tip, torque and rotations forces are less than the designated amount “built in” the slot which need over correction to compensates for play.
•The curve of Spee will return or deepen after appliance removal.
•Teeth adjacent to an extraction site will tend to rotate and tip towards the extraction site.
•As teeth in the buccal segments settle they will rotate and tip mesially, so if they are overcorrected and slightly tipped distally, they will tend to settle better than teeth that are already mesially inclined.
•As band spaces close, there is a corresponding loss of torque of the anterior teeth.www.indiandentalacademy.com
OVERCORRECTION
Extracted teeth with Roth Rx SWA brackets, showing over correction built in to the brackets
Extracted teeth with Andrews SWA brackets showing non – orthodontic normal tooth position.
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ROTH CONCEPT OF SELECTION OF TREATMENT MECHANICS
Thorough diagnosis
Establishing treatment goals
Dynamic treatment planning
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The traditional method of selecting treatment
mechanics, based on the Angle's classification of
malocclusion, is inadequate.
Treatment mechanics should be selected by the
set of conditions that exist along with the
parameters that are placed on the situation.
(The treatment mechanics must be tailored to the
individual situation and the individual facial type).
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•In diagnosis and treatment planning, it is necessary to diagnose the case from a mandibular position of centric relation, if one wish to treat centric relation occlusion.
•One must utilize a specific set of criteria for a functional occlusion goal throughout diagnosis, treatment planning, and retention
•One must have records. (Standard orthodontic models and cephalometric centric relation head films) taken in centric relation as well, if any significant centric discrepancy exists in a particular case
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CO - CR discrepancy
The neuromuscular positioning of the mandible will accommodate to existing occlusal discrepancies and hide the true nature of malocclusion
So a REPOSITIONING SPLINT should be fabricated
•To get the patient's mandible into centric and
•To make the true discrepancy apparent.
Once the discrepancies are apparent, one should make a treatment plan to deal with all of the discrepancies present in the case and not just one to cover only those discrepancies he can see intraorally.
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•Those that are used on
normal to brachyfacial types.
Those that are used for the more dolichofacial types
TREATMENT MECHANIC
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TREATMENT MECHANIC SELECTIONS - FACTORS TO BE CONSIDERED.
•The facial type of an individuals.
•Reactions of various facial types to the proposed
treatment.
•How much growth remains and in which direction the
mandible can be expected to grow and what means must
be taken to alter the direction of this growth - favourably
with treatment mechanics.
•Effect of treatment mechanics on the patient's soft
tissue profile.
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TO PLAN AND TO SELECT APPROPRIATE TREATMENT MECHANICS, ROTH UTILIZED.
•An adjusted head film tracing from centric
(habitual) occlusion to centric relation.
•Ricketts VTO and
•The five position superimposition
•Jarabak analysis
.
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The five position superimposition is utilised to quantify
•The amount of growth needed to correct the jaw relationship.
•The amount of orthopedic changes or jaw relationship changes necessary to correct the dental arch relationship and
•The extent of tooth movement allowable or desirable both anteroposteriorly and vertically of the anterior and posterior teeth in each arch.
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Jarabak analysis
For qualitative assessment of the facial type and its probable response to the various kinds of treatment mechanics and growth.
The most important measurementsare
•The anterior to posterior face height ratio,
•The tendency of the individual facial type
to rotate clockwise or counter clockwise
during growth, and
•a response to certain treatment mechanics
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Treatment goals
1. Pleasing facial esthetics, evaluated by soft tissue and skeletal measurements cephalometrically.
2. Molar relation and tooth alignment, evaluated by Angle's description of anatomical occlusion.
3. Functional occlusion, evaluated gnathologically on an articulator.
4. Stability of postreatment tooth positions and alignment.
5. Comfort, efficiency, and longevity of the dentition, supporting structures, and the temporomandibular joints.
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ROTH'S ORTHODONTIC TREATMENT GOALS FOR AN IDEAL FUNCTIONAL OCCIUSION
.I- Centric occlusion or
maximum interuspation of
the teeth should occur
with the mandible in
centric relation, in which
they condyles are
centered transversersy
and seated against the
articulator disks at the
posterosuperior slopes of
the eminencewww.indiandentalacademy.com
This centric relation occlusion should have three point
contact of the opposing centric cusps in their respective
fossae.
II- Mutually protective occlusion
Occlusal force during closure should be of equal magnitude for all posterior teeth and the stress should be directed along the long axes of the teeth and the lower incisors should not be in contact with the lingual surface of upper incisors and should have a clearance of 0.005 inch
(by transmitting all the occlusal
forces, the centric stops of the
posterior teeth will protect the
anterior teeth from lateral stress).www.indiandentalacademy.com
Anterior guidance / incisal guidance
In straight protrusion the anterior teeth should serve as a gentle glide path to disclude the posterior teeth very gently. To have such anterior guidance, there should be minimal but sufficient anterior overbite.
In the absence of anterior guidance,
excessive lateral stress on the
cuspids may cause lingual movement
of the lower cuspids and resultant
lower anterior crowding, and/or
labial movement of the maxillary
cuspids and affects post treatment
stability.
No stress
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Canine guidance / canine rise In lateral excursions the maxillary
cuspids should act as guiding inclines to disclude the teeth on
the balancing or non-functioning side and to disclude the teeth on
the working or functioning side after approximately .5mm of group contact.
balancing working
R L
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In a "mutually protective" occlusion
•The anterior teeth protect the posterior teeth from
lateral stress during protrusive movement and
The posterior teeth protect the anterior teeth from lateral
stress during closure into centric relation occlusion
•So in a mutually protective occlusion, the mandible can
execute its total range or envelope of motion without
interference from the teeth and
During closure the teeth will direct and maintain centricity
of the condyles in the fossae
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III -Tooth-to-two-teeth or cusp-embrasure occlusion
During maximum intercuspation, there should should be
Tooth-to-two-teeth or cusp-embrasure occlusion between
the upper and lower teeth, because this make the lateral
and protrusive movements with proper cuspid and incisor
contact.
IV- Tooth structure, tooth position
and occlusal form should correlate
perfectly with mandibular border
movements, including the Bennett
movement and immediate side shift.
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ROTH'S ORTHODONTIC TREATMENT GOAL FOR AN
IDEAL STATIC OCCLUSION.
In terms of tooth alignment, the goal primarily is one is in very close harmony to that described by Andrews in his "six keys to normal occlusion".
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ROTH SETUP
Roth setup is available in both 0.018 and 0.022 slot
Roth preferred 0.022 slot brackets because it offered
more advantages
•In terms of wire size selection,
•In terms of stabilizing arches as anchor units and for
orthognathic surgery and
•For control of torque in the buccal segments, which is
very important from the standpoint of functional
occlusion. www.indiandentalacademy.com
The Roth setup incorporated into it a member of hooks for various types of elastic configuration and also double triple and lip bumper tube for the use of auxillary wires and attachments.
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Bracket positioning with Roth set up
The bracket placement vary slightly from the position advocated by Andrews, thus a flat, unbent, rectangular, full sized wire can be used as the finishing wire rather than one with reverse and compensating curve.
Reference point – Andrews FA point
The point on the facial axis that
separates the gingival half of the
clinical crown from the occlusal half.
The key in determining the bracket height is the canine and premolars (second premolars is an extraction case).
Ideally the center of the bracket should be placed at the maximum convexity of the crowns of the posterior teeth. In a teeth with average height of gingival attachment, the maximum convexity of the teeth will be at the center of the clinical crown.
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Molars(upper/lower)
From the buccal From the occlusal
Both the right and left bands should be checked to ensure that they are in the same relative position on the crowns
M B
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Premolars(upper/lower)
From the buccal From the occlusal
Upper premolar bracket placement is the most variable because of tooth size. The most common error is not placing the bracket gingival enough, especially on smaller sized teeth.
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Upper and lower Canine
From the buccal From the occlusal
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Upper and lower incisors
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Upper arch
Central tip torque rotation
Andrews 5 7 0
Roth 5 12 0
Lateral 9 3 0
9 8 0
If it is increased the resultant axial is esthetically and functionally undesirable
The 5° torque increase in torque improves
•Ethetics by preventing flattened profile, straight upper lip and obtuse nasolabial angle.
•Provide more space for lower anterior teeth, thereby aiding classI intercuspation and
•Establish proper anterior guidance & prevent lateral stress in posterior segments
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Upper canine
tip torque rotation
Andrews 11 -7 0
Roth 13 -2 4M(mesial)
•Increased because they are being retracted in most treatment.
•Less negative torque to offset the reciprocal effect of building more positive torque into the incisors.
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I&II PM tip torque rotation
(A) 2 -7 0
(R) 0 -7 2D
IM &IIM (A) 5 -9 10
(R) 0 -14 14D
• Elimination of the mesial tip on all buccal segment teeth strengthened anchorage control significantly (but burning anchorage can be difficult).
•To offset mesial the rotation that accompanies distal traction
•The distal rotation of mesiobuccal
cusp with reciprocal mesial rotation M B
of mesiolingual cusp due to which cusp
the cusp to cusp relation is changed
to class I molar relation.
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LOWER ARCH
CENTRAL &LATERAL
tip torque rotation
(A) 2 -1 0
(R) 2 -1 0
CANINE
(A) 5 -11 0
(R) 7 -11 2M
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I PM tip torque rotation
(A) 2 -17 0
(R) -1 -17 4D
II PM 2 -22 0
-1 -22 4D
I M 2 -30 0
-1 -30 4D
II M 2 -35 0
-1 -30 4D
• Because these teeth settle more mesially than the upper and simultaneously rotate mesially thus necessiating extra distal roration
• No change in the torque-To establish proper functional occlusionwww.indiandentalacademy.com
ROTH TRU-ARCH FORM
Roth Tru-Arch form was derived from his
extensive clinical testing and recording of jaw-
movement patterns in treated patients who were
out of retention and had remained stable.
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. The Roth Tru-Arch form actually overcorrects the arch width slightly.
In the front part of the arch, the widest part is at the bicuspids, not at the cuspids.
The widest point in the entire arch is at the first molars region,(mesiobuccal cusp of I molar) There are actually five arcs in the Arch
•A curve across the front
•A Curve in cuspid-bicuspid area
•A uniform curve in the buccal
segment to allow for proper
rotational position of the buccal
segment teeth.www.indiandentalacademy.com
SEQUENCING OF TREATMENT OBJECTIVES
The sequence of the treatment should be based on
the dictates of the individual case. The sequence of
treatment objectives are generally.
1. Eliminating cross bite
2. Correcting jaw relationship
3. Eliminating severe crowding creating space in the
dental arches for severely malposed, impacted or
blocked teeth,
4. Aligning the teeth in the individual arches,
5. Beginning space consolidation
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6. Finishing the lower arch
It is of utmost importance that the lower arch must be finished in the correct position to act as a template to receive the upper teeth, so that the upper teeth can be set to the lowers
7. Achieving class I relationship of buccal segment,
8. Retracting and as if necessary intruding maxillary arterior teeth.
9. Detailing and finalizing the tooth position and the occlusion.
In many instances a number of these steps will be combined and will be occurring simultaneously. www.indiandentalacademy.com
THE THREE PHASES OF TREATING MALOCCLUSION
INCLUDES
Phase I unlocking the malocclusion
Phase II Working phase.
Phase III Finalization or detailing of occlusion
•To initial phase of treatment usually entails the use of some of the following appliances
•Split palate Hass - type appliance
•Quard helix
•Transpalatal bar and / or a lingual arch
•An occipital pull headgear or facebow to the 6 years molar
•Utility arch. www.indiandentalacademy.com
Anchorage consideration
Factors responsible for anchorage loss
1. Attempting to upright extremely distally tipped canines.
2. Pulling distally with posterior teeth against extremely procumbent or labially inclined incisors.
3. Attempting to level the curve of Spee with a continuous wire without the use of distal traction.
4. Attempting to do any of the first three tooth movements utilizing either a stiff or a resilient wire.
5. Attempting to move lingually or torque the maxillary incisor roots.
6. Attempting to expand the mandibular arch with a labial archwire.
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some of the ways in which one can avoid using extra oral traction or losing anchorage are
•The leveling process should be started with a small
flexible wire. The best for this purpose is the braided arch
wire.
•When it is time to retract and upright lower anteriors
that have been in labial or procumbent position, they
should be retracted initially with an anterior facebow. In
most instances 6 to 8 weeks of headgear to the lower
anterior segment is all that is needed to upright the lower
anterior teeth sufficiently that the remainder of the space
can be closed with reciprocal mechanics. www.indiandentalacademy.com
•Band the second molars at the outset of full dentition
treatment and use them for anchorage. It is much more
difficult to displace the buccal segments in the
mandibular dental arch forward if the second molars have
been included as part of the anchorage unit.
•When leveling the curve of Spee, wherever possible a
utility arch should be used to intrude the incisors followed
by canine by Bioprogressive technique and then going to
the flexible small wires to gain bracket engagement and
alignment of the entire arch and gradually level the
remainder of the curve of Spee.
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Phase I treatment
•Helical loop archwires, Jarabak fashion made from 0.016”
Elgiloy green wire(crowing) or
0.015” braided archwire(routinely)
or
Nitinol(severe rotation)
• 0.019” braided wire
• 0.018”Australian special plus.(finalisation of any stuborn rotation)
•0.019” square blue Elgiloy utility arches are used in case of intrusion of incisor teeth.
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Second phase of treatment.
Anterior teeth are generally retracted en masse as a group of 6 second molars are routinely banded at the outset of treatment in the permanent dentition.
Double keyhole loop wire mechanics (0.019 x 0.026” round edge rectangular)- In case of minimum and moderate anchorage cases-
Modified Asher facebow- used in cases that need maximum anchorage and retraction.
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At the end of space closure
Double keyhole loop wire mechanics
0.018x0.025” blue elgiloy incorporating exaggerated R &
C curve with special torque adjustments(to offset the the
undesirable effect produced by R & C curves) to provide
•Rapid root paralleling
•Leveling of Curve of spee &
•Maxillary incisors lingual root torque
Replaced by
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During extraction space closure, faster the space is closed, regardless of wire size, the more tipping there will be into the extraction space.
So it is the force & rate at which the extraction space is closed determines the type of tooth movement(tipping or bodily) and not the dimension of the wire used.
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FINISHING PHASE
. The final finishing phase of treatment require filling of the bracket slot (0.022 x 0.025) to get full bracket expression.
Short class II or III elastics are used to create anteroposterior denture adjustments.
DETAILING OF TOOTH POSITION
THE MANDIBULAR ARCH
Lower incisors
•The sequence of tooth positioning
begins with placing the lower incisors
teeth at or slightly lingual to the
cephalometric goal. (-1 to A-Pog)www.indiandentalacademy.com
over jetOver bite
2.5 mm 2.5 mm 0.005”
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•The four incisors teeth should have the roots divergent and roots appears to be in the same plane of space when viewed from the superior aspect.
•Lower cuspid crowns should have 5 degrees angulation with the incisal tip 1mm higher than the incisal edge of, the lateral incisors And it should have should have a slightly exaggerated mesial rotation on extraction cases.
•There should be overcorrection of root parallelism in the extraction site, if extractions were done.
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•Bicuspids and molars should be upright and should have slight distal rotation.
•There should be no spaces, and the arch form should be symmetrical.
•The widest point of the mandibular arch should be the mesiobuccal cusps of the maxillary Imolars and the I bicuspid.
•The curve of Spee should be leveled.(because it return to a 1- 1.5mm curve, at its deepest point, after appliance removal and settling of the occlusion
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MAXILLARY ARCH
In the upper arch, the first tooth to be placed properly in relation to the lower arch should be the maxillary six-year molar.
The upper six-year molars should have sufficient distal rotation, mesioaxial inclination, and buccal root torque, so as to fit with the lower six-year molars, as described by Andrews
The maxillary twelve-year molar
The upper bicuspids
The upper anteriorswww.indiandentalacademy.com
•The incisal edges of upper centrals and laterals should
be almost at the same level with no more than 0.5mm
height differential approximately
•The widest point of the maxillary arch should be the
mesiobuccal cusps of the maxillary six-year molars.
•Cusp tip of the canine should be app 1-1.5mm incisally
than the of the occlusal plane.
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ROTH’S CONCLUDING STATEMENT
“I have tried to present a philosophy of treatment with the concept of overcorrection, based on the specific set of goals stated at the outset, taking in to account existing conditions, facial types, and reaction to treatment mechanics.
Naturally there are always exceptions to the way one approaches treatment”
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REFERENCES
•Treatment mechanics for the straight wire appliance- RONALD H. ROTH
•orthodontics - current principles and techniques- Thomas M. Graber, Brainerd F. Swain
•Treatment concepts using the fully preadjusted three-dimensional appliance- RONALD H. ROTH
•Orthodontics- current principles and techniquesThomas M. Graber, Robert L. Vanarsdall
•Five year clinical evaluation of the Andrews S-W appliance- Roth
•The straight wire appliance 17 years later- Roth
•Functional occlusion for orthodontics-Roth-part I II III IV
•Straight wire design strategies - five year clinical evaluation of the Roth modification of Andrew SW appliance-Lee W. Graber.
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Thank you
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