Mais conteúdo relacionado Semelhante a How SPEED Appliance is Effective in Torque Control, Space Closure and Sliding Mechanics (12) Mais de Dr Sylvain Chamberland (20) How SPEED Appliance is Effective in Torque Control, Space Closure and Sliding Mechanics1. How SPEED Appliance is
Effective in Torque Control
Effective Torque
Torquing moment
Sliding mechanics
Enmasse retraction
drsylchamberland@biz.videotron.ca
2. Effective Torque .022 slot
• Torque play • Effective torque
! .017 x .022 = 22,3° ! 0°
! .019 x .025 = 10,5° ! 5°
! .021 x .021 = 5° ! 6°
! .021 x .025 = 3,9° ! 7,1°
.020 x .025
! .020 x .025 SW ! 4° ! ! 7°
©Dr Sylvain Chamberland
3. Effective Torque .018 slot
• Torque play • Effective torque
! .017 x .022 = 5,4° ! 5,6°
! .017 x .025 = 4,5° ! 6,5°
! .018 x .025 = 2° ! 9°
©Dr Sylvain Chamberland
4. Mc / Mf > 1
• A rectangular arch wire fitting into a rectangular slot can generate the
moment of a couple necessary to control root position.
! The wire is twisted (placed into torsion) as it is put into the bracket slot.
! The two points of contact are at the edge of the wire, where it contacts
the bracket.
• The moment arm therefore is quite small, and forces must be large to
generate the necessary MC.
• Using the same tooth, a 50 gm net lingual force would generate a 750 gm-
mm moment. To balance it by creating an opposite 750 gm-mm moment
within a 0.5 mm bracket, a torsional force of 1500 gm is required.
©Dr Sylvain Chamberland
Downloaded from: Proffit: Contemporary Orthodontics, 4th edition (on 5 April 2009 03:18 PM) © 2007 Elsevier
5. • Moment of force, MF1, = F1 X D1
• Moment of couple Mc = F2 X D2
• D1 > D2
• Therefore, to produce moments of equal
magnitude, the forces F2 creating the couple
must be of greater magnitude than F1
©Dr Sylvain Chamberland
6. • Moment required to torque maxillary incisal segment
! = 3000 -3500 g-mm (Nikolai 1985)
! 1000 g-mm for 2 incisors, 2500 g-mm for 4 incisors (Burstone)
! 2000g-mm ! 20 Nmm
• To not overcome the torquing moment of 20 Nmm, the
retraction force should be of low magnitude
©Dr Sylvain Chamberland
7. Nmm
Torque expression of self-ligating brackets compared
with conventional metallic, ceramic, and plastic brackets
Morina et al EJO 2008 (30) 233-238
Badawi, et. al. AJODO 2008; 133:721-8
• At 20° of torsion; .019 x .025 w; .022 slot
• At 12° & 24°: A-SLB > P-SLB • SPEED = 8 Nmm, torque loss 11°
• At 36° of torsion • This is consistant with Badawi
study: 24°! 11,8 Nmm
• No difference in the torquing
moment between P-SLB and A-SLB
• One would assume that with a .020 x .25 SW or .021 x .021 x .020
torque would be first expressed at a smaller angle
• Higher torquing moment would be generated at smaller angle of twist
©Dr Sylvain Chamberland
8. Comparison of torque expression between
SS, TMA and CuNiti in metallic SLB
AO 2010 #80; 884-889
In-Ovation-R
• At 36°: Mean torque difference within 5%
between all brackets when SS was compare
with either NiTi or TMA
• At 24°
Damon 3MX • SS ! 1.5 to 1.8 times the torque of TMA
• SS ! 2.5 times the torque of Niti
• Speed and In-Ovation-R: Ealier engagement of
torque at 5°
SPEED • Damon 3Mx: Engagement at 10-12°
©Dr Sylvain Chamberland
9. • At 25° of twist: Mc ! 35Nmm
• No statistic " between the 3 Bk
• At 20° of twist: Mc ! 21 Nmm
Damon Q
• More than Morina et al because it is measured at the bk
and not at 10 mm away
• SPEED brackets that clip did not
opened have similar torque curve as
Damon and In-Ovation R
In-Ovation-R • Conclusion
"Bracket
deformation
occurs above 30°
of twist
"Likely a significant
factor in loss of
SPEED NTP torque expression
Mechanical effects of 3rd movement in SLB by the measurement of torque expression
AJODO 2011;139:e31-e44
for both SLB and
Twin conventional Bk
©Dr Sylvain Chamberland Dashed line = expressed torque
Journal of Dental Biomechanics Vol 2010 (2010), Article ID 397037, 7 pages
10. Weakness & Bias of this Study
Mechanical effects of 3rd movement in SLB by the measurement of torque expression
AJODO 2011;139:e31-e44
• Data of SPEED bracket that clips opened are
pooled with bracket that did not opened, even
if a statistical differences between the 2 sub-
SPEED-NTP N = 14 group was established
! "SPEED NTP have similar torque curves as Damon and In-Ovation R"
• Plastic deformation of wire or the brackets
alone are unknown
• Torquing moment behond plastic deformation
of the wire is unknown
• Torquing moment at yield point of the
©Dr Sylvain Chamberland brackets is unknown
11. Home Made Fancy Study
• H1: A 45° or so angle of twist in a .019 X .025 SS wire do
not create plastic deformation
• H1: REJECTED
©Dr Sylvain Chamberland
12. Home Made Fancy Study
• H2: A 45° or so angle of twist do not debond a bracket
• H2: REJECTED
©Dr Sylvain Chamberland
13. Home Made Fancy Study
• H3: A 45° or so angle of twist create plastic deformation
of the bracket
• Since bond failure occurred, a fancy lab study is required
• To know at which angle and torquing moment bracket
deformation occurs, a non deformable material should be
used instead of a SS wire
©Dr Sylvain Chamberland
15. What are the limits of 1/-SN
1/-SN = 72° 1/-SN = 103° 1/-SN = 126°
- 31° + 23°
©Dr Sylvain Chamberland
16. • A single force applied at the crown create uncontrolled
tipping which improve incisor torque
! The crown move in the opposite direction of the root
GR 21-06-10 GR 20-09-10 GR 01-11-10
20x25 nitisw 21x21DW 16x22 neost
16SC for 6 weeks !16x22 neost for 6 weeks !20x25 nitisw for 6 weeks !21x21 Dwire
©Dr Sylvain Chamberland
17. 1/-SN = 72° +28° 1/-SN = 100°
• 16SC (6 w) !16x22 neost (6 w) !20x25
nitisw (6 w) !21x21 Dwire (6 w) !Stop
ABP, bond 6's/ & 7's/, 16x16sent (6 w) !
20x20neost (6 w) !20x25 niti (6 w)
!20x25 SS (6 w) ! 20x25 SS + ART (6 w)
• Significant torque increased was
obtained in 65 weeks through a
progression of at least 5 wires
• 28° is below the angle at which bracket
deformation could occur
©Dr Sylvain Chamberland
18. Wire progression = torque correction
1/-SN = 82° +14° 1/-SN = 96°
•.016SC (6w)!.018SC (6w) !.020x.020NiTi (12w) !
!.020x.025 Niti (12w)!.020x.025 SW (16w)!
!.021x.025SS
• Torque has improved with engagement of
full size archwire
Em.Ja. 0909 Em.Ja. 0910
©Dr Sylvain Chamberland
20. Maintain torque while
retracting
1/-SN = 112° -16° 1/-SN = 96°
•.016SC (6w)!.016x.022Niti (8w) !
!.020x.020NiTi (14w) !.019x.025 TMA (10w)!
!.021x.021x.020 retmasse SW (12m)!
!.021x.021Dwire SS
• Maintain low force module while retracting to
not overcome Mc generated at the bracket
interface
• Increased wire cross section to increase stiffness
in torsion and reduce torque play
• Mx & Md advancement is planned
Se.Ma. 0308 Se.Ma. 0810
©Dr Sylvain Chamberland
22. Maintain initial torque
103° to 104° = maintain
• .016SC (12w)!.018SC (16w) !.016x.022NiTi (6w) !
!.020x.025 Niti (6w)!.019x.025 TMA (12w) !
!.020x.025 Niti (6w) ! .020x.025 SW (8w)
• 1/1 improved because /1-MP improved
• Early engagement of full dimensional archwire
helped to maintain adequate torque
Ja.Le. 0808 Ja.Le. 0510
©Dr Sylvain Chamberland
23. Ectopic lateral incisor
• Early engagement of rectangular
wire and 0° torque Bk on lateral
incisor was efficient and effective to
obtain alignement in the 3rd order
plane of space
• .020 x.020 Niti!.020x.025Niti!
!.020x.025SW
• Finishing: .021x.025SS (8 m)
©Dr Sylvain Chamberland
Lateral incisors Bk prescription: 0°
24. Assessment of Slot Sizes in Self-ligating Brackets
using Electron Microscopy
N.B. BHALLA, S.A. GOOD, F. MCDONALD, M. SHERRIFF, A.C.CASH
• Aim: to assess the slot dimensions in the 0.022-inch bracket
different commercially available self-ligating bracket systems,
, in six
of an upper left central incisor
using electron microscopy , in order to
determine the accuracy of manufacturers published dimensions
• SmartClip, Clarity SL, SPEED, Damon MX, In-Ovation R, In-Ovation C
©Dr Sylvain Chamberland
25. Assessment of Slot Sizes in Self-ligating Brackets
using Electron Microscopy
N.B. BHALLA, S.A.GOOD, F.MCDONALD, M.SHERRIFF, A.C.CASH Aust Orthod J 2010, may 26
• Results
! All of the brackets systems measured had slot sizes that
were significantly greater than their stated 0.022-inch
dimension
! Speed brackets (Strite Industries) were 5.1% larger, and
found to be the closest dimensions to those published.
! The largest bracket was the Smartclip bracket (3M)
measured to be 14.8% bigger than 0.022 inches
©Dr Sylvain Chamberland
26. • Clinical implication
! Increased slot dimensions reduces the expression of bracket
prescription in all three dimensions.
! Dimensional inaccuracies lead to teeth moving by tipping, rather
than bodily movement.
©Dr Sylvain Chamberland
27. Orthodontic Bracket Manufacturing Tolerances and Dimensional
Differences between SLB
Major T et al, J Dental Biomechanics, v 2010
Nominal height=0,559 mm
• SPEED: Smaller than nominal height, larger at bottom than the top
• In-Ovation: Taper!Smaller at the bottom, larger at the top
• Damon: Larger than nominal height
©Dr Sylvain Chamberland
28. Orthodontic Bracket Manufacturing Tolerances and Dimensional
Differences between SLB
Major T et al, J Dental Biomechanics, v 2010
• Tolerance of slot height of SPEED = 15#m smaller than nominal
• Tolerance of slot height of In-Ovation = 15#m smaller at bottom
& bigger at the top
• Tolerance of slot height of Damon Q = 43#m bigger (oversized)
• An oversize/undersize of 15#m means ±2,3° of torque play
• An oversize/undersize of 43#m means ±4,7° of torque play and a
reduced torque expression (Mc) of 5-10 Nmm
• Difference between SPEED and Damon = 15 + 43#m or 7° of
torque play
©Dr Sylvain Chamberland
29. • If an .022" slot bracket is actually . TABLE 1
TIPPING DUE TO LOSS
OF TORQUE CONTROL*
0235" (~ 7%) Torque Loss
5° 8° 10°
Maxillary 1.3mm 2.1mm 2.7mm
Mandibular 1.2mm 1.9mm 2.3mm
! An .019 X .025 or an .0215 X .028 archwire will *Lingual change in incisal edge position (incisors of average dimensions).
have 5° of wire bracket play beyond that usually
anticipated for an .022" slot.
• When protracting posterior teeth,
SIATKOWSKI, JCO 1999, p 509
! If the mechanics depend upon moments generated at
the incisor brackets with rectangular archwires, the
above slot-size errors can induce lingual tipping of
the incisors
! Such results are undesirable, to say the least. If the
archwires are smaller than their stated sizes, the
impact is even worse
©Dr Sylvain Chamberland
31. Some thoughts about friction
LLY
• Most study are bench study
INIC
A
R CL
! Test .019 x .025 SS wire or similar C CU
VE RO
E
Nangulation) & wire is pulled at a
• Bracket held steady (no
NS
IT O
rate of 10 mm/ Iminute (Stefanos S., Secchi A. et al, AJODO 2010)
ND
CO
• CH
SUBracket sliding on a steady wire at a rate of 1 mm/minute
(Budd S., Dask J.Tompson B. EJO 2008; Oliver C. Dask J.Tompson B.
AO 2011)
©Dr Sylvain Chamberland
32. Change over time in canine retraction: an
implant study
Parsekian, R, Bushang, P.H., Gandini L.G., Rossouw P.E., Am J Orthod Dentofacial Orthop 2009;136:87-93
©Dr Sylvain Chamberland
33. Rate of tooth movement
• 10 mm / minute ! 432 000 mm per month
• 1 mm / minute ! 43 200 mm per month
• Average of 1,42 mm / month ! 0,00003287 mm per
minute
©Dr Sylvain Chamberland
34. Some other thoughts about
friction
• Findings:
! Passive SLB produce less frictional resistance than Active SLB
! However, this decreased friction may result in decreased
control compared with actively ligated systems
• All wire tested were rectangular ! activate the clip (active zone)
©Dr Sylvain Chamberland
35. • If bracket held steady (no angulation)
! RS is lower for all SLB than for
conventional bracket tied with wire or an
elastomeric ligature and lower with passive
clip than active
• This condition never occurs clinically!
©Dr Sylvain Chamberland
36. • As soon as the corners of the
bracket contact the wire (2nd order),
binding occurs, and this contribute
most of the resistance to sliding
• Binding do not appear to be affected
by the method of ligation
• Same binding and notching could be
expected in the 1st order
# Heavy forces = more rotation and anchorage loss
Yee et al, AJODO 2006; 136:150.e1-150.e9
©Dr Sylvain Chamberland
37. Friction
Conclusion
• Clinical studies support the view that resistance to sliding
has little to do with friction and, instead, is largely a
binding-and-release phenomenon that is about the same
with conventional and self-ligating brackets.
• The limited clinical trial data now available do not support
the contention that treatment time is reduced
(presumably because of lower friction) with self-ligating
brackets
Friction and resistance to sliding in orthodontics: a critical review. AJODO 2009; 135:442-7
©Dr Sylvain Chamberland
38. Ligature derived force
Reznikov, N et al, Measurement of friction forces between stainless steel wires and reduced-friction self-ligating brackets, AJODO 2010;
138:330-8
• Depends on ligation mode
! Can be smaller in SLB or greater in conventional systems
"Shear force increase linearly with wire deflection relative to the
bracket slot
"Friction resistance is proportional to the grade of the wire
securing elements rigidity and to the extent of wire deflection
• Correlation between passive clip design and wire surface
scratching
©Dr Sylvain Chamberland
39. Reznikov, N et al, Measurement of friction forces between stainless
steel wires and reduced-friction self-ligating brackets, AJODO 2010;
138:330-8
• Some clip flexibility might provide a considerable benefit during
the working stage of the orthodontic treatment, when residual
malalignment of the teeth still persists.
• Either an active clip or an elastomeric module can absorb minor,
clinically undiscernible tooth irregularities and does not hinder
sliding mechanics.
• In contrast, a passive clip demands ideal alignment of the teeth
subjected to a retraction force.
©Dr Sylvain Chamberland
40. Therefore
Wi.Be.290609 Wi.Be.120809 Wi.Be.250909
• Swinging the teeth on a very small wire
• Few if any friction is involved:
! Passive zone
! No binding
! No notching
Wi.Be.131109 Wi.Be.100510
©Dr Sylvain Chamberland
41. • The width of the bracket on a tooth determines the length of the
moment arm (half the width of the bracket) for control of mesiodistal
root position.
• Bracket width also influences the contact angle at which the corner of
the bracket meets the arch wire. The wider the bracket, the smaller the
contact angle.
• In the 1st order, the clip prevent rotation and help reduce the moment
arm in that plane
©Dr Sylvain Chamberland Downloaded from: Proffit: Contemporary Orthodontics, 4th edition (on 5 April 2009 03:23 PM)
© 2007 Elsevier
42. Do We Need a Fancy Study
to...
• Know that .019x.025 TMA (or
SS) will generate more Friction
(FR) than a smaller wire ?
• Know that increased retraction
force will cause more tipping of
the tooth to retract and
therefore Binding (BI) and An.No 310308
Notching (NO) is more likely to Resistance to slide
occur?
©Dr Sylvain Chamberland
43. Do We Need Fancy Study
to...
• Know that .020 SS wire has less
friction than .019x.025?
An.No 250608
Resistance to slide
©Dr Sylvain Chamberland
44. Do We Need Fancy Study
to...
• Know that pulling on 1 side and
pushing from the other side make
it easier to translate teeth over a
rounded corner of an anterior
arch form?
An.No 110309
Resistance to slide
©Dr Sylvain Chamberland An.No 081209
45. Do We Need Fancy Study
to...
• Know that T loop retraction
springs are...frictionless?
©Dr Sylvain Chamberland
46. Re.Ba. 0906 Sliding a single tooth
• .021 x .021 x .020 HDG
• Elastomeric chain 7-6-5-o-3
Re.Ba. 0107
! Round wire to reduce Friction
! Lower force to reduce Binding & Notching
Re.Ba. 1007
Re.Ba. 0907
©Dr Sylvain Chamberland
47. Sliding a single tooth
• .021 x .021 x .020 HDG
•
Re.Ba. 0906
Compressed coil 22-24
! Round wire reduced Friction
! Low force reduced Binding & Notching Re.Ba. 0107
• Auxilliary wire .016
• .016 x .022 HA niti
Re.Ba. 0907
Re.Ba. 1007
©Dr Sylvain Chamberland
48. • Mx: 021x021x020: #13 is retracted
individually
• Md: 021x021x020: #46 is protracted +
upright spring to increase anchorage
Es.Gr1210
• Mx: $ E link: space is opening mesially
• Md: New 021x021x020 X 58 mm
! To include 1st premolar
! Increase wire stiffness
Es.Gr0111
• Mx: $ 020 SS wire.
! Class I canine achieved
! Elastomeric chain activated ~ 2 mm
for the lateral
Es.Gr0311
• Md: $ E link
49. Rate of tooth movement under heavy and light
continuous orthodontic forces
Yee J.A., Elekdag-Türk T., Cheng LL, Darendeliler MA, AJODO 2009; 136:150e1-150e9
• Initial tooth mvt benefits from light forces
• Heavy forces increased rate of tooth mvt and
amount of canine retraction BUT increased
anchorage loss and loss of canine rotation control
• Maximum anchorage cases benefits from light
forces
©Dr Sylvain Chamberland
50. Tipping and translating
Am.Bu. 0500 • Distal tipping + rotation Am.Bu. 0800
• T-loop for root uprighting
Am.Bu. 1000
©Dr Sylvain Chamberland Am.Bu. 0101
51. Hills DUAL-GEOMETRY Wire™
• Full sized square anterior section fills the
slot of optimal torque control
! Torque play = 5°; Effective torque ! 6°
• Rounded posterior section is
polished to minimize friction
! Estimated torquing moment: ~ 15 Nmm
.021 X .021 X .020
• Made of an ultra-high tensile strength stainless steel for optimum stiffness.
©Dr Sylvain Chamberland
52. Hills DUAL-GEOMETRY Wire™
Anterior section - square
• Mx:
! 38 mm: to include 4 incisors
! 55 mm: to include canine to canine
Posterior section- round
• Md:
! 45 mm: to include canine to canine
! 58 mm: 1st premolar to 1st premolar
©Dr Sylvain Chamberland
53. En masse retraction
• .021 X .021 X .020 Hills Dual geometry
• Cl I module: E-Link E-5
! Force 100 to 125 g
• Reverse curve of Spee
! Moment to counteract tipping
! Posterior toe in or constriction
©Dr Sylvain Chamberland Downloaded from: Proffit: Contemporary Orthodontics, 4th edition (on 3 May 2007 06:18 PM)
© 2007 Elsevier
54. Force system
(M/F =10:1)
• Translation: ~ 100 g
! To maintain torque control when closing space
! Use low force module
©Dr Sylvain Chamberland
Downloaded from: Proffit: Contemporary Orthodontics, 4th edition (on 3 May 2005
55. 01-03
• Enmasse space closure
! 021 X 025 SS + oxydoreduction of 05-03
the posterior section distal to 1st
premolar
• Molar protraction
! Note that flat curve of Spee is 11-03
maintained
©Dr Sylvain Chamberland
56. Enmasse retraction: Anchorage A
08-04
• .021 x .025 SS DG
! Upright spring on /3's
! E5, 75g/side 09-04
! Protraction of lower 5's
• .021 x .021 x .020 HDG $ E-links 5
11-04
! OJ and Cl I molar
relationship is improving
$ E-links 5
©Dr Sylvain Chamberland
57. 12-04
• Use cl II to improve
molar relationship
01-05
• Upright spring to PM2
• E6 47-P; E5 P-36 03-05
©Dr Sylvain Chamberland
58. Molar protraction
09-04 11-04 12-04
• Time: 8 months
• Note space opening between the premolar and the molar
01-05 03-05 04-05
©Dr Sylvain Chamberland
59. Pa.Ge.0803
.021 x .025 SS + oxydoreduction
Space close in 5 months
Flat curve of Spee is maintained
Pa.Ge.1003
Pa.Ge.0104
©Dr Sylvain Chamberland
60. Ka.Sw.200504
• Adult, cl II div 1, missing #36
• Tx plan:_________
Ka.Sw.050804
©Dr Sylvain Chamberland
61. Ka.Sw.300505 at 1 year into tx
• Note space opening distal to 46 & 37
Ka.Sw.210905
•
©Dr Sylvain Chamberland
Once 46 is contacting 44, start protraction of 47
62. Ka.Sw.191005
• TPA removal, reassessment of Bk position, cl II elastic
©Dr Sylvain Chamberland
63. Ka.Sw.160106
• Duration: 108 weeks Ka Sw
Ka.Sw.260606
©Dr Sylvain Chamberland
64. Mc / Mf > 1
Moment / Force
• Problem •Solution: M c > MF
–Increase moment at the wire/bk
! Loss of incisor torque interface
!! wire stiffness
! Mx: reverse curve of spee
!RC in Md
! Md: increased curve of spee !AC in Mx
–Reduced force level
©Dr Sylvain Chamberland
65. Molar protraction
• Enmasse .021 x .021 x .020
• E-links : 7's - hook
Fo.Mi 0407
Fo.Mi 0206
Fo.Mi 1208
©Dr Sylvain Chamberland
67. Molar protraction
• Enmasse .021 x .021 x .020
• E-links : 6's - hook
• Uprighting spring 17-15
! to overcome tipping in the 2nd order
Da.Ga.210209 Da.Ga.300910
©Dr Sylvain Chamberland
68. Molar protraction
• Such large protraction of the 2nd molar resulted in mesial
rotation in the 1st order
• Class I force module from the lingual helped to correct
rotation in the 1st order while the uprighting spring
corrected the tipping in the 2nd order
©Dr Sylvain Chamberland
Da.Ga. 0109 Da.Ga. 0410 Da.Ga. 0910
69. 2 nd Molar Protraction
Tx initiated: Dec 07 Na.Ru.030809 At 19 m Na.Ru.121010
Na.Ru.140907 Na.Ru.261009 At 23 m Na.Ru.121010 At 34 m
©Dr Sylvain Chamberland
70. Enmasse incisor retraction
• .017 x .025 ß-Ti mushroom wire
• Preactivation bend
! Accentuated curve of Spee
! Anterior step up
! Posterior toe in
• Activation
! Pull & cinch
©Dr Sylvain Chamberland
73. SPEED Wire™
• Torque play on top
• Wire is seated at the
bottom of the slot
•Active • Passively seated
• Actively maintained
• Torque play
! .020 x .025 ! 4°
• Effective torque
! .020 x .025 ! 7°
• Spring-Clip activated by "cam" • Archwire and archwire slot
action of SPEED archwire in perfect alignment
Seating the spring clip 0.01 mm
©Dr Sylvain Chamberland created an arc of 5,4 mm at the apex
74. Other finishing wire
D-Wire
.020 x .020 SS
• Torque play
! .020 x .020 ! 6°to 7°
• Effective torque
! .020 x .020 ! 4° to 5°
D-Wire
• Torque play
! .021 x .021 = 5°
• Effective torque .019 x .025 SS or %-Ti
.021 x .021 = 6°
!
• Torque play
! .019 x .025 = 10.5°
• Effective torque
! .019 x .025 = ±9°
(for the lower anteriors)
! .019 x .025 = 5°
(for upper anteriors)
©Dr Sylvain Chamberland
75. Finishing
Ca.Gr.0907 Ca.Gr.1208 Ca.Gr.0309
• Prior to surgery .020 x .025 SW + finishing bend
• Root torque achieved
Ca.Gr.0907
©Dr Sylvain Chamberland
Ca.Gr.1208 Ca.Gr.0309
76. 3 rd order problem
Labial root torque Lingual root torque
Ev. Ca.0507 Ev. Ca.0309
• Most of my problems encountered in the 3rd order
plane of space where caused because I used (from
1998 to 2005) an undersized .019 x .025 archwire (SS
or %-Ti)during finishing stage
Ev. Ca.0909
• Since I reintroduced .020 X .025 or .021 X .025
archwire, I significantly reduced the needs of torquing
©Dr Sylvain Chamberland spring in finishing except for a few particular situations
77. Torque issue in finishing stage
• Engaging a continuous archwire will cause 3rd order discepancy that will need to
be address in the finishing stage Da.Pa 0706
Da.Pa 0908. Da.Pa 280109
• .020 x .025SS was engaged in June. Torquing spring were added in september
• Adequate alignement of incisors's talon was achieved in January
©Dr Sylvain Chamberland
78. An.No 05-7, tx initiated 0607
• Tx time = 130 weeks
• Got it straight + a new
born baby
An.No 12-09
©Dr Sylvain Chamberland
80. Ja.Le. 07-8, tx initiated 0808
• Tx time: 92 weeks
• Slight residual midline deviation
Md deviation
Ja.Le. 05-10
©Dr Sylvain Chamberland
82. 11 y. 4 m. Ta.Po. 09-08, tx initiated 011008
• Tx time: 92.7 weeks
Ta.Po. 12-07-10
©Dr Sylvain Chamberland
84. Class III
Severe ALD
Vi.Lé.02-10-07
• Hopeless #16 (UR 1st molar)
• Mx midline deviated to the right
©Dr Sylvain Chamberland
85. • Dentoalveolar
Protrusion
• Lower lip
procumbency
©Dr Sylvain Chamberland
86. Tx planning
• Tx goals
! Reduce lip procumbency
! Obtain coincident midline
! Achieve cl I canine
! Achieve cl I molar on the left
! Achieve cl III molar on the right
• Extraction: ?
©Dr Sylvain Chamberland
87. Vi.Lé.03-07-08
• Mx:.020 x .020 neost + .016 SC
• Md: .021 x .021 x .020 enmasse retract.
©Dr Sylvain Chamberland
88. Vi.Lé. 01-10-08
• At 50 weeks
• Mx: .016 X .022 neost; #13 engaged
©Dr Sylvain Chamberland
89. • Reassessment of bracket position
! 14, 13, 12, 11, 22, 23, 24, 33
©Dr Sylvain Chamberland
90. Vi.Lé. 28-01-09
• At 67 weeks
• Mx & Md: .019 x.025 Resol, finishing bend
©Dr Sylvain Chamberland
91. Vi.Lé. 23-03-2009
• At 75 weeks
• Mx: .019 x .025 resol., finishing bend 21, 12
• Md: .020 x .025 SW, finishing bend 43, 45
©Dr Sylvain Chamberland