Download Troubleshooting of problem cases with orthodontic mini

2013-03-19
CASE 1
A combination of mini-implant
and MEAW to correct a skeletal
Class II open bite
Before treatment
After treatment
Before treatment
After treatment
Tae-Woo Kim DDS MSD PhD
Professor, Department of Orthodontics
School of Dentistry
Seoul National University
Seoul, Korea
Before treatment
CASE 2
After treatment
CASE 3
Contents
MEAW
Intrusion methods of posterior teeth
Extrusion or Intrusion Mechanics
Etiology of Open bite
Combination of two mechanics
Extraction options
There are two mechanics, extrusive and intrusive.
Next, I would like to suggest guidelines, cases and
indications for each of them.
In my clinic, I have many open bite cases with TMD, because they are referred
from local clinics and other dentists. Seoul National University Dental Hospital is
the final destination of problem cases.
1
2013-03-19
Mouth
Mouth
breathing
breathing
Ankylosed
Tongue
incisors
thrusting
thrusting
Open
bite
bite
TMD
sucking
Tongue
incisors
Open bite cases have causes,
some of which are not
uncontrollable or even unknown.
This makes it very difficult to
treat them and/or retain their fine
results.
Open
Thumb
Ankylosed
Thumb
TMD
sucking
MacroBrazil
glossia
Italia
Open-bite cases look very similar. All of open bites have different causes.
Supplied by RMO
Difficult to finish
Sometime it goes back!
Macroglossia
Method 5 : Use a mid-palatal mini-implant
Methods
to intrude the posterior teeth
Method 1
Method 2
Method 3
Method 4
Method 5
Method 6
System of Method 5 is as follows;
Methods were summarized into 6 categories.
1.
2.
3.
4.
Place a mid-palatal mini-implant(1.6 mm x 6 mm) , as far distally as possible.
Use a TPA with hooks.
Insert an 019x025” ss archwire.
Apply a power chain tightly.
Structure
2
2013-03-19
Method 1
Method 2
Method 3
Method 4
Method 5
Disdvantages of Buccal Mini-implants
in Open bites
Four methods use buccal mini-implants between 6 and
7. But Method 5 doesn’t use buccal mini-implants.
In open-bite cases, the buccal screws between the
first molar and the second molar fail very
frequently.
Disdvantages of Buccal Mini-implants
in Open bites
Disdvantages of Buccal Mini-implants
in Open bites
• The stability is compromised when the
implants are placed near the alveolar crest
and/or into the periodontal membrane.
1) The inter-radicular space between the first molar and
the second molar is very small.
2) In open bite cases, as the posterior teeth being
intruded, the screw becomes closer to the alveolar
crest and the periodontal membrane.
Disdvantages of Buccal Mini-implants
in Open bites
In most of cases, the inter-radicular space between
6 and 7 is narrow. 1) Then, it is inevitable to place a
mini-implant between 5 and 6. The mechanical
efficiency to intrude the posterior teeth will be
decreased. 2) Possibility of Root trauma is high.
Shingo Kuroda, Kazuyo Yamada, Toru Deguchi, Takashi Hashimoto, Hee-Moon Kyung, Teruko
Takano Yamamoto, Root proximity is a major factor for screw failure in orthodontic anchorage, Volume
AJODO 2007:131(4) :S68-S73
Advantages of Method 5
1. A mid-palatal mini-implant is more stable than a
buccal mini-implant between 6 and 7.
2. A mid-palatal mini-implant can be placed more
distally than a buccal mini-implants between 5 &
6. The mid-palatal one is better in biomechanical
aspects (longer lever arm) to intrude the posterior
teeth.
3. Only one mini-implant is required.
3
2013-03-19
Extrusion or Intrusion
Extrusion or Intrusion
mechanics to treat the open bite
mechanics to treat the open bite
Orthognathic
Surgery
Orthognathic
Surgery
vs
Orthodontic
treatment
vs
Orthodontic
treatment
MEAW
MEAW
1. Incisal display
2. Lip incompetency
3. Skeletal pattern
Extrusion of
Anterior Teeth
Mini-implant
Intrusion of
Posterior Teeth
Open bite always means the intrusion of upper posterior teeth? No. I
would like to emphasize three factors in differential diagnosis to select
the adequate mechanics.
Extraction options in Class II
open-bite cases
77
77
88
88
MEAW
77
88
44 or 55 88
55
88
Extraction
1. Incisal display
2. Lip incompetency
3. Skeletal pattern
Extrusion of
Anterior Teeth
Non Non
-ext -ext
77
77
77
88
77
88
Mini-implant
Intrusion of
Posterior Teeth
Some cases were treated by combining the MEAW technique and the
mini-implant intrusion.
88
88
Extraction
1. Extraction of third molars brought spaces for second molars to be
intruded and tipped back.
77
77
Extraction
Effects of seond molar extraction are as follows,
By extracting third molars, bite closing is facilitated.
1. Center of rotation moves forward. Lever arm becomes longer than third
molar extraction.
4
2013-03-19
77
77
Extraction
55
55
Extraction
(or 44 )
55
2. Wedge (second molars) is removed.
3. Number of teeth to be intruded are reduced.
4. RAP can be utilized.
55
55
Extraction
2. Wedging molars are moved forward.
55
55
Extraction
2. Wedging molars are moved forward.
Extraction of bicuspids also helps bite closing, because
1. Number of teeth to be intruded are reduced.
55
55
Extraction
2. Wedging molars are moved forward.
55
55
Extraction
2. Wedging molars are moved forward.
5
2013-03-19
55
55
Extraction options in Class II
open-bite cases
Extraction
77
77
77
88
88
88
00
08
Non-ext
(presence
of 8)
Indications
44
55
2. Mesial movement of wedging molars are good to resolve the open bite.
55
55
Extraction options in Class II
open-bite cases
Extraction options in Class II
open-bite cases
77
77
77
77
77
88
77
88
88
88
88
88
00
08
Non-ext
(presence
of 8)
Clinical notes
Third molars erupt faster than usual. But the secondary minor
orthodontic treatment may be required to align the third
molars especially, for lower ones.
55
55
Indications
44
55
Extraction options in Class II
open-bite cases
77
77
77
77
77
88
77
88
88
88
00
08
Non-ext
(presence
of 8)
00
08
Non-ext
(presence
of 8)
Indications
55
55
1. Upper third molars are good in shape. But lower
ones are abnormal in shape or impacted.
2. The angle between upper 7 & 8 is between 20~30
degrees. Lower ones are impacted.
3. Upper third molars have erupting potential.
Adolescent patients are good.
55
55
Extraction options in Class II
open-bite cases
44
55
00
08
Non-ext
(presence
of 8)
44
55
88
88
1. Third molars are good in shape.
2. The angle between 7 & 8 is between 20~30
degrees.
3. Third molars have erupting potential. Adolescent
patients are good.
1. In adolescent or adult patients, third molars are not
good in shape or impacted.
Clinical notes
1. Bite closing is slower than in 7-extraction cases.
44
55
55
55
Clinical notes
1. Bite closing is much slower than in 7-extraction
cases.
2. This option is not recommended. Please, extract
third molars before closing the bite.
6
2013-03-19
Extraction options in Class II
open-bite cases
Extraction options in Class II
open-bite cases
77
77
77
77
77
88
77
88
88
88
88
88
00
08
Non-ext
(presence
of 8)
00
08
Non-ext
(presence
of 8)
Indications
44
55
1. Class II canine and molar relationship
2. Severe upper anterior protrusion and labial
inclination,
3. Or upper anterior crowding.
55
55
Extraction options in Class II
open-bite cases
77
77
77
88
88
88
55
55
1. Class II canine and molar relationship
2. Mild to moderate upper anterior protrusion with
normal labial inclination,
3. Or slight upper anterior crowding.
Clinical Tips for Method 5
(Mid-palatal mini-implant & TPA
for intrusion of upper posterior
teeth)
00
08
Non-ext
(presence
of 8)
44
55
Indications
44
55
Clinical notes
1. Bite closing is facilitated by extraction of 5s.
55
55
Clinical Tip I for a mid-palatal miniimplant
Tae-Woo Kim DDS MSD PhD
Professor, Department of Orthodontics
School of Dentistry
Seoul National University
Seoul, Korea
Copyright belongs to Dr. Tae-Woo Kim.
Please, don’t copy and distribute without permission.
Clinical Tip II for a mid-palatal miniimplant: How to ligate the power
chain
Method 1 using an undercut
Big screw head
Method 2 using a hole
Hole
• There should be some space between the TPA and
palatal tissue, which prevents the palatal bar to
impinge the palatal tissue as the molars are being
intruded.
7
2013-03-19
Insert the ligature wire into the holes of the power chain as the figure shows.
Put the center ring around the screw neck.
Hook the ligature wire around the neck of screw.
Pull the ligature wire with a hemostat.
Twist the ligature.
8
2013-03-19
Cut the ligature and bend the remaining portion around the neck.
Stretch the power chain tight and hang it up to the hook of TPA.
Clinical Tip III for a mid-palatal
mini-implant
Long shank
(113-MD-204)
Use a long shank wrench. Please, give a 6 mm space between the
bottom of the handpiece and the incisial edge. If the bottom of the
angle touches the incisal edge, it will be impossible to remove or insert
the screw anymore.
3mm
X≥6
2010.7.16
•2-way ANOVA
•Post-hoc test
Male
6>X≥5
5>X≥4
4>X≥3
Female
3>X
2mm
In every patients, please measure a mid-palatal bone thickness. A midpalatal mini-implant, 1.6x6mm, is used.
Kang, SM, Kim, TW, AJODO:2007:131(4)-Supplement 1:74-81
Award of the best poster at KAO 2004
9
2013-03-19
Clinical Tip IV for a mid-palatal miniimplant
566513 박명인
Place the mini-implant more distally + Extend the arch anteriorly!
582424 이민아
(O)
Then, upper poster teeth will be intruded more efficiently.
(X)
Place the mini-implant more distally + Extend the arch anteriorly!
Clinical Tip V for a mid-palatal miniimplant
566513 박명인
Clinical Tip VI for a mid-palatal
mini-implant
2010.9.10
582424 이민아
(O)
(X)
Attach the hooks distally and gingivally.
Clinical Tip VII for a mid-palatal miniimplant
• If the insertion torque is higher than
30Ncm, use predrilling.
566513 박명인
Extract the upper third molars or second molars to remove
the wedging effect and to provide the space for intrusion.
• Orthonia® (RMO)
- Wireless rechargeable handpiece
- Stops automatically when torque increases
over 30 Ncm.
Jeilmedical Co. Seoul, Korea
10
2013-03-19
How to remove the fractured tip
Implant Trephine kit
Problems experienced in mid-palatal mini-implants
I experienced mini-implant fracture in two cases. In these cases I felt
that their bones were much harder than usual. My fault was that
excessive torque was applied more than 50Ncm. (In most of cases, less
than 30Ncm is enough to place mid-palatal mini-implants without
drilling.) Orthonia is good because it stops automatically at 30Ncm. If it
stops, remove and drill. Then we can avoid fracture of a screw.
Trephine (=2 mm) adequate to the size of fractured tip was selected.
1) Expose the fractured tip after
retracting a flap.
2) Reposition the flap and suture.
Clinical Tip VIII for a mid-palatal
mini-implant
Method 5
1.6x6mm
29759(536480)이민형
A TPA with crown buccal torque and a midpalatal miniimplant was used to intrude the molars. The main arch
wire is 019x025 ss with a slight crown buccal torque. This
arch is expanded a little.
Clinical Tip IX for a mid-palatal
mini-implant
:How to control 2nd molars
1) Solder hooks to intrude 2nd
molars palatally
Sometimes, upper 1st molars are intruded but 2nd molars
don’t follow.
11
2013-03-19
2) Add a L loop with an intrusion
step between 6 and 7
to intrude 2nd molars buccally
Clinical Tip X for a mid-palatal miniimplant
1) Monitor the extrusion of lower molars
Clinical Tip X for a mid-palatal miniimplant
2) If lower molars extrude, then apply
the mechanics of lower molar intrusion.
Burstone
lingual arch
1.6x6mm
This is the method using a Burstone lingual arch with lingual
crown torque and a buccal mini-implants to intrude the lower
molars. Crown lingual torque is applied slightly to counteract
the buccal tipping by the intruding force from the power
chains.
Clinical Tip XI for a mid-palatal miniimplant
Intruding force should be strong.
Clinical Tip XII for a mid-palatal
mini-implant
; Retain the TPA and mid-palatal miniimplant during the finishing stage.
2011.5.4 After intrusion
2012.2.29 Debonding
(O)
(X)
Initial counterclockwise rotation of mandible relapsed
during the detailing stage.
Extrusion of upper molars was a cause of the changes.
It is recommended to retain them as long as possible
during the finishing stage.
12
2013-03-19
Clinical Tip XIII for a mid-palatal
mini-implant ;
Fixed retainer + Labial buttons + U/D
elastics
How will you solve the relapse after
debonding?
1. Exercise not to thrust tongue during
swallowing.
2. Check TMJ pains.
3. Chew thirty times for one bite.
4. Fixed retainers + labial buttons (22/33) +
u/d elastics 3/16” 3½ oz
How to make labial button?
Adhesive application
Curing
How to make labial button?
Curing
Separator
Removal
How to make labial button?
Etching
Drying
How to make labial button?
Separator
Ring
Placement
Flowable Resin
Application
How to make labial button?
Labial Button
13
2013-03-19
Multiloop Edgewise Arch
Wire (MEAW)
– 018x022 stainless steel
.022 X .028
Upper
Lower
MEAWs are made of 018x022 ss wire.
He invented MEAW technique
•Class II correction
U:
MEAW
L:
Ideal arch wire
•Class III correction
U:Ideal
L:
arch wire
MEAW
Closing anterior open bite
U:
MEAW
L:
Nov. 25, 2002, After lecture at Department of Orthodontics, SNU
MEAW
MEAWs can be used to correct Class II relation, Class III
relation and open bite. To close the anterior open bite, MEAWs
are used both in upper and lower arches.
14
2013-03-19
•Class II correction
U:
MEAW, L: Ideal arch wire
5/16”
Class II elastics
To correct Class II relationship, MEAW is applied in the
maxillary arch and Ideal arch(019x025ss) is used in the
mandibular arch. Class II 5/16” 6oz elastics are applied.
•Class III correction
U:
Ideal arch wire, L: MEAW
5/16”
Class III elastics
To correct Class III relationship, MEAW is applied in the
mandibular arch and ideal arch(019x025ss) is used in the
maxillary arch. Class III 5/16” 6oz elastics are applied.
•Openbite correction
U:
MEAW, L: MEAW
3/16”
up/down elastics
•018x022 stainless steel
To close the anterior open bite, MEAWs are used both in maillary
and mandibular arches. 3/16” 6oz elastics are applied from the first
upper loop to the first lower loop.
An 043-CK plier is used to make a MEAW.
To make MEAWs, 4 to 5 L-shaped loops are made between teeth.
First, anterior curvature is bent with a turret.
15
2013-03-19
6mm
2.5mm
2 1 4.5mm
3
Between #2 and #3, the first L loop is being bent.
Between #2 and #3, the first L loop is made.
8mm
7mm
7
6
6mm 7mm 7mm 6mm
5
4
3
2.5mm
2 1 4.5mm
Sequentially, upper L loops are being made.
Size of L loops
8mm
7mm
7mm
The final upper and lower MEAWs were made.
7
7
6
6
8mm
6mm 7mm 7mm 6mm
5
5
4
3
4
3
6mm 6mm 7mm
2.5mm
2 1 4.5mm
2 1 4.5mm
2.5mm
6mm
16
2013-03-19
5~10°
20~25°
Upper and lower MEAWs showed a good coordination.

Upper
To avoid gingival impingement or cheek mucosa irritation, L
loops have a buccal tipping. The angle increases progressively
distally.

Lower
But the upper and lower MEAWs don’t have torques.
Tip back bends

The arch is made flat.
Provides reverse curve of Spee
Tip back bends are applied to each loops, 3° to 5°.
Finally, the upper arch has a compensating curve and the
lower arch has a reverse curve of Spee.
17
2013-03-19
“Rocking Chair”
v
Up & Down
elastics
1. Extrusion of anterior teeth is the main effect.
1. Extrusion of anterior teeth is the main effect.
2. Very slight intrusion of posterior teeth is also secondary effect,
“Rocking chair effect”.
“Rocking Chair”
1. Extrusion of anterior teeth is the main effect.
2. Very slight intrusion of posterior teeth is also secondary effect,
“Rocking chair effect”.
“Handle of a car”
1. Extrusion of anterior teeth is the main effect.
2. Very slight intrusion of posterior teeth is also secondary effect,
“Rocking chair effect”.
3. Distal tipping contributes to the correction of molar relationship.
This effect is increased by Class II elastics (In Class III, by
Class III elastics).
4. .
“Handle of a car”
1. Extrusion of anterior teeth is the main effect.
2. Very slight intrusion of posterior teeth is also secondary effect,
“Rocking chair effect”.
3. Distal tipping contributes to the correction of molar relationship.
“Molar movement in open-bite”
Very slight intrusion + Distal tipping
18
2013-03-19
Reasons why I use MEAWs instead
of curved TMA or NiTi wires?
“Handle of a car”
Distal tipping or intrusion of a molar can be controlled very
accurately and effectively with a stiff stainless wire. And also the
load-deflection rate is decreased well with the L loops.
“Handle of a car”
Summary
• Some of skeletal open-bite cases can
be treated orthodontically,
– by extrusive mechanics (MEAW) or
– by intrusive mechanics (Mini-implant).
• Three factors- incisal display, Lip
incompetency, and skeletal pattern - were
1. If the handle is made of a flexible material, it would not be easy
to control well (tip-back and intrusion) and
2. it would be hard to adjust the wires (vertical or in-&-out steps)
for compensating the minute errors of bracket positioning.
suggested to select the mechanics
differentially.
Summary
• Combination of a MEAW with a midpalatal mini-implant
– produces intrusion of upper posterior teeth
and extrusion of anterior teeth at the same
time. And this may close open bite very
rapidly just after extraction of 2nd molars.
19