RAPID MAXILLARY EXPANSION VS SLOW MAXILLARY EXPANSION
1. RME VS SME
Presented by
Dr. SHEHNAZ JAHANGIR
IInd YEAR MDS
DEPT. OF ORTHODONTICS
NICDS
2. Content
• Introduction
• Historical Perspective
• Articulation Of Maxilla
• Ossification Of Mid Palatal Suture
• Indication For Expansion
• Contraindication For Expansion
• Classification Of Expansion
• Based on On Activation
• Based On Support
3. • RME Appliance System
Hass
Hyrax
Issacson
Leaf Expander
Butterfly Expander
Fan Shaped Expander
• Activation Protocol
• Biomechanical Aspects
• Effects Of RME On Skeletal And dental Structure
4. • Slow Maxillary Expansion Appliance
Quad Helix
Niti Expanders
W Arch Expander
Spring Jet
• Comparative Evaluation Between RME And SME
• Literature review between Rapid and Semi Rapid appliance
system
• SARPE
• MARPE
• Alternate Maxillary Expansion And Contraction
• Conclusion
• References
5. INTRODUCTION
• The constricted maxilla dentally or skeletally always poses a problem for
an orthodontist . It has been recognized for the thousands of years and
Hippocrates referred to it.
• Growth ceases first in the transverse dimension. So diagnosing and
treating this problem first is an integral part in orthodontics .
• The maxilla and upper teeth positions are governed by the musculature
surrounding them, in patients showing constricted maxillary arch it is
mandatory to deal with by applying an orthopedic forces across the maxilla
for expanding it
6. • EMERSON.C.ANGELL in 1860,
placed a screw appliance b/n
maxillary premolars for a girl aged
14 ½ years and widened the arch ¼”
in 2 weeks.
• Molars in their position take up
precise position .Nature provides a
sure and unriding guide to correct the
occlusion of jaw despite the primary
dentition has gone !!!
Timms, D.J., 1999. The dawn of rapid maxillary expansion. The
Angle Orthodontist, 69(3), pp.247-250
7. • The appliance was neither
cemented nor cribbed .It was held
by the force of the screw on to the
neck of the tooth
• By end of 2 weeks, jaw was
widened leaving space between 2
central incisors indicating maxillary
bone have been separated
Timms, D.J., 1999. The dawn of rapid maxillary expansion. The Angle
Orthodontist, 69(3), pp.247-250
8. Body of the maxilla articulates with the following bones :
Cranially :
1) Frontal
2) Ethmoid
Facially :
1) Nasal
2) Lacrimal
3) Inferior nasal conchae
4) Vomer
5) Zygomatic
6) Palatine
9. • The sphenoid bone forms the
midsagittal part of the anterior and
middle portions of the cranial base
lies just posterior to the maxillae
• The pterygoid plates of the sphenoid,
bilaterally positioned, do not have a
midsagittal suture that allows them to
be displaced laterally.
Bishara , S.E. and Staley, R.N., 1987. Maxillary expansion: clinical
implications. American journal of orthodontics and dentofacial
orthopedics, 91(1), pp.3-14
10. • The pyramidal processes of the
palatine bones interlock with the
pterygoid plates
• Confining effect of the pterygoid
plates of the sphenoid minimizes
the ability of the palatine bones to
separate at the midsagittal plane.
• As the maxillae start to separate,
the zygomatic processes offer some
resistance to expansion
Bishara , S.E. and Staley, R.N., 1987. Maxillary expansion: clinical
implications. American journal of orthodontics and dentofacial
orthopedics, 91(1), pp.3-14
11. Ossification of mid palatal suture
• In stage A, the midpalatal suture
is almost a straight high-density
sutural line with no or little
interdigitation
• In stage B, the midpalatal suture
assumes an irregular shape and
appears as a scalloped high-
density line
• some small areas where 2
parallel, scalloped, high-density
lines close to each other and
separated by small low-density
spaces
12. • In stage C, the midpalatal
suture appears as 2 parallel,
scalloped, high-density lines
that are close to each other,
separated by small low-
density spaces in the
maxillary and palatine bones
• In stage D, the fusion of the
midpalatal suture has
occurred in the palatine
bone, with maturation
progressing from posterior to
anterior
Angelieri, F., Cevidanes, L.H., Franchi, L., Gonçalves, J.R., Benavides, E. and McNamara Jr, J.A., 2013.
Midpalatal suture maturation: classification method for individual assessment before rapid maxillary
expansion. American Journal of Orthodontics and Dentofacial Orthopedics, 144(5), pp.759-769.
13. • In stage E, fusion of
the midpalatal suture
has occurred in the
maxilla.
• The actual suture is
not visible in at least a
portion of the maxilla
Angelieri, F., Cevidanes, L.H., Franchi, L., Gonçalves, J.R., Benavides, E. and McNamara Jr, J.A., 2013.
Midpalatal suture maturation: classification method for individual assessment before rapid maxillary
expansion. American Journal of Orthodontics and Dentofacial Orthopedics, 144(5), pp.759-769.
14. Clinical implication
• Stages A and B a conventional RME approach would have
less resistant forces and probably more skeletal effects
• Initial diagnosis of stage C might indicate that the timing of
RME is critical because the start of fusion of the palatine
portion of the suture could be imminent.
• In stages D and E might be better treated by surgically
assisted RME because fusion of the midpalatal suture already
has occurred partially or totally
15. Indications
Bishara , S.E. and Staley, R.N., 1987. Maxillary expansion: clinical
implications. American journal of orthodontics and dentofacial
orthopedics, 91(1), pp.3-14
16. Contraindications
Uncooperativ
e patients
Single tooth
cross bite
Anterior
Open bite
Assymetric
Maxilla
Fusion of mid palatal
suture
Steep Mandibular
Plane
Bishara , S.E. and Staley, R.N., 1987. Maxillary expansion: clinical
implications. American journal of orthodontics and dentofacial
orthopedics, 91(1), pp.3-14
17. Orthodontic Expansion:
Orthodontic expansion is produced by conventional fixed appliances
and by various removable expansion plate and finger spring
appliances It usually result in lateral movements of the buccal
segments that primarily are dentoalveolar
Graber, L.W., Vanarsdall, R.L., Vig, K.W. and Huang, G.J., 2016. Orthodontics-E-Book: Current
Principles and Techniques. Elsevier Health Sciences.
Orthopedic Expansion:
Changes are produced primarily in the underlying skeletal structures
rather than by the movement of teeth through alveolar bone.
Passive Expansion
When the occlusion is shielded from the forces of the buccal and
labial musculature, a widening of the dental arches often occurs.
This expansion is not produced through the application of extrinsic
biomechanical forces, but rather by intrinsic forces such as those
produced by the tongue.
18. Based on rate of activation
Rapid Maxillary
Expansion
Slow Maxillary
Expansion
Semi Rapid
Expansion
19. Tooth and tissue borne appliances
1.Derichsweiler type
2.Haas type
Tooth borne appliances
1. Isaacson type
2. Hyrax type
20. DERISCHSWEILER:
(1953):
Tags are welded & soldered to
palatal aspect of bands to
provide attachment for acrylic
which is extended to palatal
aspect of non-bonded teeth.
Almuzian, M., Short, L., Isherwood, G., Al-Muzian, L. and McDonald, J., 2016. Rapid
maxillary expansion: a review of appliance designs, biomechanics and clinical
aspects. Orthodontic Update, 9(3), pp.90-95
21. HAAS TYPE EXPANDER:
• The first type of expansion screw
popularized by Haas in 1961.
• It consists of bands placed on
maxillary 1st premolars and molars.
• A midline jackscrew is incorporated
into the acrylic pads that closely
contact the palatal mucosa.
• 0.045inch SS wire soldered to
palatal aspect of the bands.
Almuzian, M., Short, L., Isherwood, G., Al-Muzian, L. and McDonald, J., 2016. Rapid
maxillary expansion: a review of appliance designs, biomechanics and clinical
aspects. Orthodontic Update, 9(3), pp.90-95
22. • Support wire extend along the buccal
and lingual surfaces of the posterior
teeth, to add rigidity to the appliance.
• Haas in 1961 stated that more bodily
movement and less dental tipping is
produced when acrylic palatal coverage
is added to support the appliance, thus
pertaining forces to be generated not
only against the teeth but also against
the underlying soft and hard palatal
tissues.
23. HYRAX TYPE EXPANDER:
• The more commonly used type of banded
RME appliance is the hyrax type expander.
• It is entirely made from stainless steel.
• Bands are placed on the maxillary first
molars and first premolars.
• The expansion screw is located in the
palate in close proximity to the palate
contour.
Almuzian, M., Short, L., Isherwood, G., Al-Muzian, L. and McDonald, J., 2016. Rapid
maxillary expansion: a review of appliance designs, biomechanics and clinical
aspects. Orthodontic Update, 9(3), pp.90-95
24. HYRAX TYPE EXPANDER:
• Buccal and lingual support wires also
may be added for rigidity.
• The maxilla opens as if on a hinge,
with its apex at the bridge of the nose.
• The suture also opens on a hinge
anterioposteriorly, seperating more
anteriorly than posteriorly.
Almuzian, M., Short, L., Isherwood, G., Al-Muzian, L. and McDonald, J., 2016. Rapid
maxillary expansion: a review of appliance designs, biomechanics and clinical
aspects. Orthodontic Update, 9(3), pp.90-95
25. Issacson expander:
(1971)
• This is a tooth borne appliance with out
any acrylic palatal covering
• Minne expander soldered directly to the
bands
• Screw reduced in length for narrow
arches
Almuzian, M., Short, L., Isherwood, G., Al-Muzian, L. and McDonald, J., 2016. Rapid
maxillary expansion: a review of appliance designs, biomechanics and clinical
aspects. Orthodontic Update, 9(3), pp.90-95
26. Butterfly ExpanderforUse in the Mixed Dentition
A new RPE appliance, called a “butterfly expander”, that is
used to treat patients in the mixed dentition was devised.
Appliance Design :
• The butterfly expander follows the basic design of
Hass, with a few modifications.
• A high midpalatal jackscrew is attached to a
butterfly-shaped stainless steel framework that
extends forward to the palatal surfaces of the deciduous
canines.
• The appliance is soldered to bands on the second
deciduous molars.
Cozza, P., Giancotti, A. and Petrosino, A., 1999. Butterfly expander for use in the mixed
dentition. Journal of clinical orthodontics: JCO, 33(10), p.583.
27. • A high -powered laser is used to weld
the two arms to the screw housing,
ensuring perfect, one-piece joints and
eliminating any possibility of detachment.
• The rigidity of the appliance and its
location high in the palatal vault allow the
transverse force to be delivered closer
to the center of resistance of the
posterior teeth than with conventional
expander.
• The butterfly design thus minimizes
posterior tipping and extrusion.
Cozza, P., Giancotti, A. and Petrosino, A., 1999. Butterfly expander for use in the mixed
dentition. Journal of clinical orthodontics: JCO, 33(10), p.583.
28. A Fan-Shaped Maxillary Expander
LUCALEVRINI JCONOVEMBER1999
• The expander is made of stainless steel, with
the spider screw as the active component.
• There are three pivot points:
• a posterior one - “fan” opening
• two anterior ones - counteract the torquing
forces produced during expansion.
• Intercanine width increased more than
intermolar width
Levrini, L. and Filippi, V., 1999. A fan-shaped maxillary expander. Journal of clinical
orthodontics: JCO, 33(11), pp.642-643.
29. • Intermolar width showed a slight expansion with fan-type RME
when compared with the conventional RME.
• The changes achieved in dentofacial structures with a
conventional RME were more stable than that achieved with
the fan-type RME.
• Fan-type RME avoided expanding and tipping the posterior
teeth, which causes increase in vertical facial height.
• The upper incisors were tipped palatally in group II and tipped
buccally in group I.
30. Leaf Expander
Lanteri et al JCO 2016
• New spring-based expander with a leaf-shaped active element.
• This Leaf Expander eliminates the need for home activation and simplifies
clinical management.
Lanteri, C., Beretta, M., Lanteri, V., Gianolio, A., Cherchi, C. and
Franchi, L., 2016. The Leaf Expander for Non-Compliance
Treatment in the Mixed Dentition. Journal of clinical orthodontics:
JCO, 50(9), p.552.
31. • The design of the Leaf Expander is similar to that of a conventional rapid palatal
expander.
• Instead of a midline jackscrew, it has a double nickel titanium leaf spring that
recovers its original shape during deactivation, resulting in a calibrated
expansion of the upper arch.
• The leaves are preactivated in the laboratory to deliver 3mm of expansion.
• The screw is blocked with metal ligatures which are removed after
cementation
• One-quarter turn corresponds to .1mm of activation; therefore, 10
activations of the screw generate 1mm of activation and,
• The maximum number of activations is 30 (6mm of expansion).
32.
33. • (1) Measure the distance between the most
gingival extension of the buccal grooves on
the mandibular first molars or,
• (2) Measure the distance between the tips
of the mesiobuccal cusps of the maxillary
first molars;
• (3) Subtract the mandibular measurement
from the maxillary measurement.
• The average differences in persons with
normal occlusion are 1.6mm for males
and 1.2mm for females
• Overexpand 2-4 mm from this
measurement
36. • When an expansion force F is
applied an equivalent moment and
force result at the centers of
resistance of each maxillary half.
• The magnitude of the moment=F*Y
• The moment equivalent (FY) tends
to cause the maxillary halves to
rotate about their respective centers
of resistance
Braun, S., Bottrel, J.A., Lee, K.G., Lunazzi, J.J. and Legan, H.L., 2000. The
biomechanics of rapid maxillary sutural expansion. American Journal of Orthodontics
and Dentofacial Orthopedics, 118(3), pp.257-261
37. • The osseous structures at the
frontonasal suture rapidly resorb to
permit rotation of the maxillary
halves about a point superior to the
center of resistance other than at
the frontonasal suture
• In the occlusal view, the fringe
patterns point to a center of rotation
at the distal aspect of the maxillary
midpalatal suture approximating the
distal one third of the third molars
Braun, S., Bottrel, J.A., Lee, K.G., Lunazzi, J.J. and Legan, H.L., 2000. The biomechanics of
rapid maxillary sutural expansion. American Journal of Orthodontics and Dentofacial
Orthopedics, 118(3), pp.257-261
38. • High stress levels were observed in
the canine and molar regions of the
maxilla, lateral wall of the inferior
nasal cavity, zygomatic and nasal
bones.
• Highest stress concentration at the
pterygoid plates of the sphenoid
bone in the region close to the
cranial base
Işeri, H., Tekkaya, A.E., Öztan, Ö. and Bilgic, S., 1998. Biomechanical effects of rapid
maxillary expansion on the craniofacial skeleton, studied by the finite element
method. The European Journal of Orthodontics, 20(4), pp.347-356
39. EFFECTS OF RME ON THE MAXILLARY COMPLEX
Rapid maxillary expansion occurs when the force applied to the teeth and the
maxillary alveolar processes exceeds the limits needed for orthodontic tooth
move- ment. The applied pressure acts as an orthopedic force that opens the
midpalatal suture.
The appliance compresses the periodontal ligament, bends the alveolar
processes, tips the anchor teeth, and gradually opens the midpalatal suture.
40. • Inoue et all found that the palatine processes of the maxillae
separated in a nonparallel- that is, in a wedge-shaped-manner
in 75% to 80% of the cases observed.
Relation between amount of sutural separation and extent of
molar expansion.
• The amount of sutural opening was equal to or less than one
half the amount of dental arch expansion. He also found that
the sutural opening was on average more than twice as large
between the incisors than it was between the molars
41. Effects of RME on maxillary complex
Maxillary halves
Displaced downward and forward
Fulcrum of rotation –frontomaxillary suture
Tipping :- -1 to 8
Sutural opening :- ≤ one half the amount of dental arch expansion
Palatine process of maxilla – lowered
Palatal dome – remained the same
Bishara , S.E. and Staley, R.N., 1987. Maxillary expansion: clinical
implications. American journal of orthodontics and dentofacial orthopedics, 91(1),
pp.3-14
42. Alveolar process
Bone is
resilient
Lateral
bending of
alveolar
process
Applied
force
dissipate
within 5-6
weeks
If
stabilization
terminated
Residual
force in
displaced
tissue
Rebound
CLINICAL TIP
Need for overcorrection – to compensate for subsequent uprighting of buccal
segment
Bishara , S.E. and Staley, R.N., 1987. Maxillary expansion: clinical
implications. American journal of orthodontics and dentofacial orthopedics, 91(1), pp.3-
14
43. Palatal vault
• Fried and Haas reported that the
palatine processes of the maxilla
were lowered as a result of the
outward tilting of the maxillary
halves.
Bishara , S.E. and Staley, R.N., 1987. Maxillary expansion: clinical
implications. American journal of orthodontics and dentofacial orthopedics, 91(1), pp.3-
14
44. Maxillary anterior teeth
• Opening of a diastema between the maxillary
central incisors.
• Incisors separate approximately half the distance
the expansion screw has opened
• After separation, the incisor crowns converge and
establish proximal contact. The mesial tipping of
the crowns is due to the elastic recoil of the
transseptal fibers.
• The maxillary central incisors tend to be extrude
relative to the S-N plane and in 76% of the cases
they upright or tip lingually.. The lingual tipping of
the incisors is due to the stretched circumoral
musculature
Bishara , S.E. and Staley, R.N., 1987. Maxillary expansion: clinical implications. American
journal of orthodontics and dentofacial orthopedics, 91(1), pp.3-14
45. Maxillary posterior teeth
• Angulation between the right and left molars increased from I deg to 24
deg during expansion which is caused by alveolar bending, but is also due
to tipping of the teeth in the alveolar bone.
Palatal mucoperiosteum, periodontal tissues, and
root resorption.
• Maxillary expansion tend to stretch the fibres of palatal mucosa which in
turn is also responsible for the 10 degree tip in maxillary molars
• Maxillary expansion is also associated with the root resorption in the
buccal aspects
46. Efects of RME on the mandible.
• There is a concomitant tendency for the mandible to swing downward and
backward.
• It is due to disruption of occlusion caused by extrusion and tipping of
maxillary posterior teeth along with alveolar bending.
Mandibular teeth
• Stay upright or relatively stable over treatment period
• Mandibular intermolar width change – 0.4mm – 1mm
Bishara , S.E. and Staley, R.N., 1987. Maxillary expansion: clinical implications. American
journal of orthodontics and dentofacial orthopedics, 91(1), pp.3-14
47. Effects of RME on adjacent facial structures.
All craniofacial bones directly articulating with the maxilla were displaced
except the sphenoid bone
• The cranial base angle remained constant
• Displacement of the maxillary halves was asymmetric
• The sphenoid bone, not the zygomatic arch: was the main buttress
against maxillary expansion.
• Gardner and Kronman, found that the lambdoid, parietal and midsagittal
sutures of the cranium showed evidence of disorientation
Bishara , S.E. and Staley, R.N., 1987. Maxillary expansion: clinical
implications. American journal of orthodontics and dentofacial orthopedics, 91(1),
pp.3-14
48. SLOW EXPANSION
It is a form of expansion which
involves increase of arch width by
movement of few teeth (or) many
teeth.
Slow expansion has traditionally
been termed dento-alveolar
expansion, although some skeletal
changes can be observed.
Expansion is at a rate of 0.5-1mm
per week.
49. SLOW EXPANSION DEVICES
• Walter Coffin – 1875
• It is a removable appliance capable of slow
dento alveolar expansion
• The appliance consists of an omega shaped
wire of 1.25mm thickness, placed in the mid
palatal region
• The free ends of the omega wire are
embedded in acrylic covering the slopes of
the palate
• The spring is activated by pulling two asides
apart manually
Almuzian, M., Short, L., Isherwood, G., Al-Muzian, L. and McDonald, J., 2016. Rapid
maxillary expansion: a review of appliance designs, biomechanics and clinical
aspects. Orthodontic Update, 9(3), pp.90-95
50. W- arch
• The W –arch is a fixed appliance
constructed of a steel wire soldered to
molar bands to avoid soft tissue
irritation.
• The W –arch is activated simply by
opening the apices of W- arch and is
easily adjusted to provide more
anterior than posterior expansion ,or
vice versa if this is desired .
Almuzian, M., Short, L., Isherwood, G., Al-Muzian, L. and McDonald, J., 2016. Rapid
maxillary expansion: a review of appliance designs, biomechanics and clinical
aspects. Orthodontic Update, 9(3), pp.90-95
51. Quad Helix Appliance:
• The appliance is constructed of
0.038 inch wire and soldered to
bands which are cemented to
either the maxillary first permanent
molar or the deciduous second
molars, depending on the age of
the patient.
Almuzian, M., Short, L., Isherwood, G., Al-Muzian, L. and McDonald, J., 2016. Rapid
maxillary expansion: a review of appliance designs, biomechanics and clinical
aspects. Orthodontic Update, 9(3), pp.90-95
52. • The desirable force level of 400 gm can be delivered by
activating the appliance by 8 mm
• The quadhelix appliance works by a combination of
buccal tipping and skeletal expansion in a ratio of 6:1 in
prepubertal childre
53. Ni Ti expander
• It generates optimal ,constant
expansion forces
• Its central component is made of a
thermally activated Ni Ti alloy and
rest of component is made of
stainless steel
Almuzian, M., Short, L., Isherwood, G., Al-Muzian, L. and McDonald, J., 2016. Rapid
maxillary expansion: a review of appliance designs, biomechanics and clinical
aspects. Orthodontic Update, 9(3), pp.90-95
54. • The expansion to the mandibular inter
molar width will provide optimal
occlusion
• It is appropriate add 1-2 mm to
expansion requirement and 2 – 3
additionally for over expansion
• If more than 8 m expansion is required
then 2 expanders are required .
Ni Ti expander
• A 3 mm increment of expansion exerts only about 350 gm of force
and the nickel titanium alloy provides relatively uniform force levels
as the expander deactivates.
55. Spring jet
• The active components of the
spring jet are soldered or attached
to the molar bands .
• The transpalatal arch replaced by
telescopic unit with Ni Ti coil spring
.
Almuzian, M., Short, L., Isherwood, G., Al-Muzian, L. and McDonald, J., 2016. Rapid
maxillary expansion: a review of appliance designs, biomechanics and clinical
aspects. Orthodontic Update, 9(3), pp.90-95
56. The telescopic unit is placed high 5
mm up from center of molar tubes so
that the forces passes close to the
center of resistance of maxillary
teeth .
But it should be 1.5 mm away from
palatal tissue
240 grams of force in mixed dentition
and 400 g spring in the permanent
dentition .
Activation: by moving the lock screw
horizontally along the telescopic
tube. A ball stop on the transpalatal
wire allows the spring to be
compressed.
Spring jet
58. Study conducted by SEVIL AKKAYA et al has proved that
• Increase in upper incisor and lower incisor inclination was greater in RME
group than SME group
• Decrease in overjet was greater in RME group than SME
• Increase in mandibular plane was greater in RME group
59. • Increase in upper canine width was greater in RME than in SME
• Regression analysis showed that arch perimeter gain is 0.65 times greater in
RME group than SME group which had 0.60 times
• It also showed that increase in arch perimeter in RME was 0.54 times
whereas in SME group it was 0.50
Akkaya, S., Lorenzon, S. and Üçm, T.T., 1998. Comparison of dental arch and arch
perimeter changes between bonded rapid and slow maxillary expansion procedures. The
European Journal of Orthodontics, 20(3), pp.255-261
60. • The greater losses in buccal bone thickness is attributed to increased dental
movement when treated with the quad-helix appliance
• With slow maxillary expansion, tooth movements through the alveolar ridge
tend to be greater than the orthopedic effects
Brunetto, M., Andriani, J.D.S.P., Ribeiro, G.L.U., Locks, A., Correa, M. and Correa, L.R.,
2013. Three-dimensional assessment of buccal alveolar bone after rapid and slow maxillary
expansion: a clinical trial study. American Journal of Orthodontics and Dentofacial
Orthopedics, 143(5), pp.633-644
61. Conclusion :
• The results suggest that the RME and SRME have a similar
effect on dentofacial structures in the transverse, vertical, and
sagittal planes.
• The amount of relapse would be less with SRME due to a
decrease in residual stresses in dentofacial structures.
62. Surgical assisted maxillary
expansion..SARPE
• Once the palatal suture are ossified along the circum-
maxillary suture it is difficult to expand maxilla using RME
,in that case surgical assisted maxillary expansion is
advocated
• The resistance is more offend from the zygomatic
maxillary suture
63. • Timms et al suggested that there are 3 stages of surgical
assistance for maxillary expansion based on the patient’s
age.
• Stage 1 (median osteotomy) is performed for patients
aged 25 years or older, or younger if rapid maxillary
expansion was tried and failed.
• Stage 2 (median and lateral osteotomies) is reserved for
those aged 30 years and older,
• Stage 3 (median, lateral maxillary and anterior maxillary
osteotomies) is for patients aged 40 years and older.
64. • The surgical method advocated is for correction of
unilateral and bilateral crossbite is different according to
Epker and Bell
Total maxillary crossbite
Bilateral maxillary crossbite
Unilateral maxillary crossbite
Bell, W.H. and Epker, B.N., 1976. Surgical-orthodontic expansion of the
maxilla. American journal of orthodontics, 70(5), pp.517-528
65. Correction of total maxillary
crossbite
• A horizontal incision is made
in the buccal vestibule
extending from the canine
region to the second molar.
• A horizontal osteotomy is
made through the lateral wall
of the maxilla 4 to 5 mm.
• The anterior portion of the
lateral nasal wall is also
sectioned
• An osteotome is used to
separate the tuberosity and
pterygoid plate.
expansion appliance is immediately
activated two one-quarter turns (0.5 mm.).
66. Correction of bilateral
maxillary crossbite
A double-Y-shaped incision is
given
• combined with vertical
interdental, laterally maxillary,
and pterygomaxillary
• Appliance is activated 4
quarter turns per day
• Similarly is for the
correction of unilateral
crossbite
Bell, W.H. and Epker, B.N., 1976. Surgical-orthodontic expansion of the
maxilla. American journal of orthodontics, 70(5), pp.517-528
67. MARPE
• MARPE is a modification of
the conventional RPE
appliance
• It consist of incorporation of
several miniscrews to ensure
expansion of the underlyng
basal bone
• Four rigid connectors of
stainless steel wire with
helical hooks are soldered on
the base of hyrax screw body.
Suzuki, H., Moon, W., Previdente, L.H., Suzuki, S.S., Garcez,
A.S. and Consolaro, A., 2016. Miniscrew-assisted rapid palatal
expander (MARPE): the quest for pure orthopedic
movement. Dental press journal of orthodontics, 21(4), pp.17-23.
68. 3 different designs of bone-borne palatal expanders using
micro-implants:
• TYPE 1: miniscrews placed lateral to midpalatal suture
• TYPE 2: miniscrews placed at the palatal slope
• TYPE 3: miniscrews as in type 1 but with additional
conventional Hyrax arms
• Type 1 stress was concentrated around the miniscrews and
the midpalatal suture
• type 2 demonstrated low stresses distributed evenly around the
microimplants
• In type 3 large amount of stress located in the midpalatal
suture and around microimplants and roots of the anchor teeth.
Suzuki, H., Moon, W., Previdente, L.H., Suzuki, S.S., Garcez, A.S. and Consolaro, A., 2016. Miniscrew-assisted rapid palatal
expander (MARPE): the quest for pure orthopedic movement. Dental press journal of orthodontics, 21(4), pp.17-23.
69. The Alternate Rapid
Maxillary Expansions and
Constrictions
• It was first reported to be
done in a patient having cleft
lip palate requiring a
expansion of more thane
15mm
• The basic concept is
alternate expansion and
constriction which will
weaken the suture and helps
in expansion
Liou, E.J.W. and Tsai, W.C., 2005. A new protocol for maxillary protraction in cleft patients:
repetitive weekly protocol of alternate rapid maxillary expansions and constrictions. The
Cleft palate-craniofacial journal, 42(2), pp.121-127
70. • The circum maxillary suture respond by the process of
sutural expansion/protraction osteogenesis, which is
similar, but less vigorous, than sutural distraction
osteogenesis.
• The similarity is that all sutures are rapidly separated or
stretched to produce osteogenesis, and the differences
relate to the mechanical approaches used (protraction,
expansion, distraction) and the varying degrees of
osteogenesis
Liou, E.J.W. and Tsai, W.C., 2005. A new protocol for maxillary protraction in cleft
patients: repetitive weekly protocol of alternate rapid maxillary expansions and
constrictions. The Cleft palate-craniofacial journal, 42(2), pp.121-127
71. Conclusion
• Palatal expansion either slow, rapid or SARPE has
become an invaluable tool to correct malocclusion in the
transverse dimension.
• Intervention with appropriate appliance in specific
situation can change an extraction protocol to
nonextraction and even a surgical requirement to
nonsurgical comprehensive treatment.
72. Refrences
• Bishara , S.E. and Staley, R.N., 1987. Maxillary expansion: clinical
implications. American journal of orthodontics and dentofacial
orthopedics, 91(1), pp.3-14.
• Timms, D.J., 1999. The dawn of rapid maxillary expansion. The Angle
Orthodontist, 69(3), pp.247-250.
• Almuzian, M., Short, L., Isherwood, G., Al-Muzian, L. and McDonald, J.,
2016. Rapid maxillary expansion: a review of appliance designs,
biomechanics and clinical aspects. Orthodontic Update, 9(3), pp.90-95.
• Braun, S., Bottrel, J.A., Lee, K.G., Lunazzi, J.J. and Legan, H.L., 2000.
The biomechanics of rapid maxillary sutural expansion. American Journal
of Orthodontics and Dentofacial Orthopedics, 118(3), pp.257-261.
• Lagravère, M.O., Heo, G., Major, P.W. and Flores-Mir, C., 2006. Meta-
analysis of immediate changes with rapid maxillary expansion
treatment. The Journal of the American Dental Association, 137(1),
pp.44-53.
73. • Cozza, P., Giancotti, A. and Petrosino, A., 2001. Rapid palatal
expansion in mixed dentition using a modified expander: a
cephalometric investigation. Journal of orthodontics, 28(2), pp.129-
134.
• Lagravere, M.O., Major, P.W. and Flores-Mir, C., 2005. Long-term
skeletal changes with rapid maxillary expansion: a systematic
review. The Angle Orthodontist, 75(6), pp.1046-1052.
• Corbridge, J.K., Campbell, P.M., Taylor, R., Ceen, R.F. and Buschang,
P.H., 2011. Transverse dentoalveolar changes after slow maxillary
expansion. American Journal of Orthodontics and Dentofacial
Orthopedics, 140(3), pp.317-325.
• Akkaya, S., Lorenzon, S. and Üçm, T.T., 1998. Comparison of dental
arch and arch perimeter changes between bonded rapid and slow
maxillary expansion procedures. The European Journal of
Orthodontics, 20(3), pp.255-261.
74. • Bell, W.H. and Epker, B.N., 1976. Surgical-orthodontic expansion of
the maxilla. American journal of orthodontics, 70(5), pp.517-528.
• Liou, E.J.W. and Tsai, W.C., 2005. A new protocol for maxillary
protraction in cleft patients: repetitive weekly protocol of alternate
rapid maxillary expansions and constrictions. The Cleft palate-
craniofacial journal, 42(2), pp.121-127.
• Kraut, R.A., 1984. Surgically assisted rapid maxillary expansion by
opening the midpalatal suture. Journal of oral and maxillofacial
surgery, 42(10), pp.651-655.
• Brunetto, M., Andriani, J.D.S.P., Ribeiro, G.L.U., Locks, A., Correa, M.
and Correa, L.R., 2013. Three-dimensional assessment of buccal
alveolar bone after rapid and slow maxillary expansion: a clinical trial
study. American Journal of Orthodontics and Dentofacial
Orthopedics, 143(5), pp.633-644.
Notas do Editor
Transverse maxillary discrepancy resulting in posterior cross bite.
A-P maxillary deficiency cases with negative ANB that would benefit from maxillary protraction. In such cases RME is required to loosen the maxilla.
Cleft palate cases with collapsed maxilla.
Cases of nasal stenosis characterized by mouth breathing & constricted nasal aperture.
Moderate arch length problems
Non Cooperative patients
Single tooth in cross bite
Anterior open bite cases
Patients with steep mandibular plane
Patients who have skeletal asymmetry of the maxilla or mandible.
Ossification of mid palatal suture is complete
Rapid expansion applinaces are activated 1 mm per day, done only when mid palatal suture is not fused
Slow expansion applinaces 1mm per week
In semi rapid expansion- RME followed by slow maxillary expansion. 2 turns each day for 1 week followed by activation once in one week