The general indications for SARPE are skeletal maturity, transverse maxillary deficiency, excessive display of buccal corridors when smiling, and anterior crowding.

1. Pocket Dentistry Fastest Clinical Dentistry Insight Engine
Surgically Assisted Rapid Palatal
Expansion
Prof. Dr. Maher Abdelsalam Fouda
Faculty of Dentistry Mansoura University

2. History of the Procedure
The procedure for transverse maxillary expansion by opening the midpalatal suture using an
orthodontic appliance was first described by Angell more than acentury ago.
It was noted that palatal expansion may result in a forward and
downward movement of the maxilla, due to resistance not entirely from the midpalatal
suture, as was thought initially, but also from surrounding bony structures, such as an Intact
zygomatic buttress, the pterygoid plates, and the piriform aperture.

3. The findings on the increased facial skeletal resistance to expansion at the
zygomaticotemporal, zygomaticofrontal, and zygomaticomaxillary articulations have led
to a better understanding of the anatomic barriers to expansion beyond the midpalatal
suture.

5. Identification of the areas of resistance in the facial skeleton has prompted the
development of various maxillary osteotomies to expand the maxilla in
conjunction with the use of orthodontic expansion devices.
In 1999, bone borne transpalatal distraction was introduced, suggesting that bone-
borne devices may overcome some potential disadvantages of tooth-
borne devices, such as undesirable movements of the abutment teeth during
expansion.
Rigid bone borne palatal distractorTooth borne palatal distractor

6. Over the years, various technical modifications have been introduced, with an
emphasis on procedures that can be performed on an ambulatory outpatient basis.
Some surgeons advocated complete separation of all maxillary articulations
and areas of resistance, whereas others advised against separation at the
pterygomaxillary junction to avoid potential pterygoid plate fracture and ensuing
complications.

7. Arguments in favor of leaving the pterygoid plates intact were based on two
principles:
first, that surgical separation at the pterygoid plates has not been shown to improve the
expandability of the maxilla or prevent relapse in a consistent manner, and second, that
surgically assisted rapid palatal expansion(SARPE) should not be done as an office
procedure under intravenous sedation if a surgeon decides to perform surgical
separation at the pterygoid plates or nasal septum, because these maneuvers may
increase the risk of significant bleeding, without any proven benefit.

8. As a measure to ensure the mobility of maxillary segments and symmetric expansion, some
have proposed the use of two paramedian palatal osteotomies, in addition to the midline
and lateral osteotomies. The paramedian palatal osteotomycuts are made from the
posterior nasal spine to a point posterior to the incisive canal.
The question of what is the
minimal procedure required to produce consistent and stable maxillary expansion in adults
has yet to be answered.
Regardless of which surgical modification is used, based on the surgeon’s training and
preference, SARPE has become an important treatment modality for
management of maxillary transverse deficiency in all types of malocclusions.

9. Indications for the Use of the Procedure
The general indications for SARPE are skeletal maturity, transverse maxillary deficiency,
excessive display of buccal corridors when smiling, and anterior crowding.
Any clinical situation in which orthodontic expansion has failed should be
evaluated for potential sutural resistance to expansion. For many
clinicians, the patient’s age and the degree of skeletal maturity are the basis for considering
nonsurgical expansion rather than SARPE. It has been shown that ossification of the
midpalatal suture has wide variations in various age groups.
In general, SARPE is recommended for patients over 16 years of age.

10. SARPE is also indicated as phase 1 surgery in the early stage of orthodontic arch
alignment and in preparation for future maxillary osteotomies for other vertical and
anteriorposterior (AP) discrepancies. In addition, it may help obviate the
need for complex segmentalization of the maxilla and hence avoid complications associated
with segmental osteotomies.

11. In summary, indications for SARPE include:
1. Increasing the maxillary arch perimeter so as to correct unilateral or bilateral
posterior crossbite, with or without additional surgical procedures
for other discrepancies.
2. Increasing the maxillary transverse width, especially when the transverse
discrepancy is greater than 5 mm.
3. Alleviating dental crowding when bicuspid extractions are not indicated.
4. Reducing excessively prominent and visible buccal corridors when smiling.
5. Overcoming resistance at the sutures and bony articulations when orthopedic
maxillary expansion has failed.

12. The determination of maxillary transverse discrepancy is based on identification of
the problem as absolute or relative. An absolute transverse discrepancy is
a true horizontal width deficiency in the maxilla, whereas a relative transverse
discrepancy is a result of the discrepancy in the maxilla or both jaws in the AP plane.
Placing diagnostic models in Class I occlusion can be helpful for differentiating
between absolute and relative transverse discrepancy. It also can yield
valuable information about the location and nature of a maxillary transverse
constriction.

13. To diagnose maxillary hypoplasia properly, a detailed clinical examination is performed and
measurements are taken. In addition, postroanterior (PA)
cephalometric radiographs can be used to identify transverse skeletal discrepancies between
the maxilla and the mandible. With the advent of three
dimensional (3D) imaging techniques and the availability of
cone beam computed tomography (CBCT) in surgery offices, clinicians now can evaluate the
actual dimensions of apical bases at different levels of the alveolar ridge in the maxilla.
A radiographic survey, clinical examination, model analysis using diagnostic
casts held in Class I occlusion, and a detailed arch length analysis provided by orthodontists
can provide the means to quantify the parameter for expansion.

14. Orthopedic maxillary expansion in a skeletally mature patient may lead to undesirable
effects on the surrounding hard and soft tissues, in addition to unstable
dental compensations due to alveolar tipping, not to mention total failure of expansion.
Therefore, it is prudent to determine the patient’s skeletal maturity and
to monitor the initial response to an orthopedic expansion and force application.
A prompt decision must be made to proceed with surgically assisted
expansion if resistance to expansion due to skeletal maturation is suspected.

15. Limitations and Contraindications
There is no absolute contraindication to SARPE. However, the procedure is relatively
contraindicated in patients with significant coagulopathy, which may
increase the risk of severe bleeding. Just as with any surgical procedure, measures are
taken to correct coagulation abnormalities and to optimize the patient’s
medical condition before surgery.
Patients with generalized periodontal disease and a heavy smoking habit should be
informed about the potential loss of gingival attachment in the maxillary anterior region.
Patient selection is important in determining the type of anesthesia to be used
(i.e., intravenous or general anesthesia); the osteotomy design
(pterygoid and/or nasal septum osteotomy) also may
influence the decision for a type of anesthesia that is appropriate for the procedure.

16. As does any other surgical procedure, SARPE has a relapse rate of 5% to 28%, and some
overexpansion should be considered to account for relapse. Advocates of the bone-
borne transpalatal distractor suggest that overexpansion is not necessary because their
study showed no relapse at the time of follow up, a finding they attributed to the direct
application of distraction forces to the skeletal base. However, further studies are
necessary to substantiate the efficacy and superiority of the bone-
borne transpalatal distractor over tooth borne devices.

17. Technique: Surgically Assisted Rapid Palatal Expansion
Either oral right angle endotracheal (RAE) tube or nasoendotracheal intubation can be used.
If a palatal osteotomy is planned, oral (RAE) endotracheal
intubation with the tube taped to the lip commissure provides the best access and
reduces the risk of inadvertently cutting into the nasal tube when making the
midpalatal cut. Neurosurgical patties are soaked in either oxymetazoline solution or
4% topical cocaine and packed into the bilateral nares for hemostasis.
oral right angle endotracheal

18. Step 1: Incision
Injections of a local anesthetic with vasoconstrictor are administered, including local
infiltrations into the maxillary vestibule and also greater palatine,
infraorbital, and nasopalatine nerve blocks. A buccal vestibular incision is made in the alveolar
mucosa approximately 2 to 3 mm from the mucogingival junction.
The incision is carried from the first molar to the canine (the same incision is made on the
contralateral side), leaving a pedicle of mucosa untouched in the midline.
Subperiosteal dissection is performed, tunneling anteriorly to the piriform aperture and
extending posteriorly to the pterygomaxillary junction.
A #9 periosteal elevator is left medial to the piriform rim and a reverse Langenbeck retractor is
placed in the pterygomaxillary fissure to protect the soft tissue.
A buccal osteotomy is made from the pterygo-
maxillary junction to the piriform rim anteriorly, using
a reciprocating saw.

19. Step 2: Buccal Osteotomy
A reciprocating saw is used to make a horizontal osteotomy cut across the anterior maxillary
wall and through the posterior lateral maxillary wall.
The cut must be made 4 to 5 mm from the apices of the maxillary dentition and
parallel to the occlusal plane.
A buccal osteotomy is made from the
pterygomaxillary junction to the
piriform rim anteriorly, using a
reciprocating saw.

20. A midpalatal incision (red line) with mucoperiosteal dissection (shaded areas)
Step 3: Palatal Incision
A midline incision is made over the midpalatal suture, extending from the posterior
aspect of the incisive canal to near the posterior edge of the hard palate.
A Cottle elevator is used to reflect the palatal mucosa, and the same instrument is
placed just posterior to the bony ledge of the hard palate to protect the soft tissue.

21. A paramedian palatal osteotomy is used
approximately 2 mm lateral to the midpalatal suture.
Two cuts are joined in the midline at a point posterior
to the incisive canal.
Note: Some surgeons may prefer not to make a
palatal mucosal incision and instead use a chisel to
split the midpalatal suture from a maxillary vestibular
approach. A midline osteotomy is made.
Step 4: Palatal Osteotomy
Starting from the posterior edge of the hard palate, a reciprocating saw is engaged to make a
palatal cut approximately 2 mm lateral to the midpalatal suture,
all the way to the point just posterior to the incisive canal.
On the contralateral side, a second paramedian cut is made approximately 2 mm lateral to
the midpalatal suture. The two cuts are joined in the midline at a point posterior to the
incisive canal.

22. followed by a midline osteotomy
using a fine straight osteotome.
Step 5: Midline Osteotomy
A vertical midline incision is made in the alveolar mucosa between the maxillary central incisors,
and a #9 periosteal elevator is used to reflect the soft tissue
just below the anterior nasal spine. As a fine straight osteotome is gently tapped into the
interseptal bone between the two maxillary central incisors, the
nondominant index finger is placed intraorally over the anterior maxilla to feel the leading edge
of the osteotome breaking through the palatal cortical bone. To
ensure complete mobilization of the maxillary segments, gentle rotation of the fine straight
osteotome results in a symmetric mobility and separation between the maxillary central incisors.

23. Step 5: Midline Osteotomy
A vertical midline incision is made in the alveolar mucosa
between the maxillary central incisors, and a
#9 periosteal elevator is used to reflect the soft tissue
just below the anterior nasal spine. As a fine straight
osteotome is gently tapped into the interseptal bone
between the two maxillary central incisors, the
nondominant index finger is placed intraorally over the
anterior maxilla to feel the leading edge of the
osteotome breaking through the palatal cortical bone.
To ensure complete mobilization of the maxillary
segments, gentle rotation of the fine straight
osteotome results in a symmetric mobility and
separation between the maxillary central incisors.

24. Step 5: Midline Osteotomy
A vertical midline incision is made in the alveolar m
ucosa between the maxillary central incisors, and
a #9 periosteal elevator is used to reflect the soft
tissue just below the anterior nasal spine.
As a fine straight osteotome is gently tapped into
the interseptal bone between the two maxillary
central incisors, the
nondominant index finger is placed intraorally over
the anterior maxilla to feel the leading edge of the
osteotome breaking through the
palatal cortical bone.
To ensure complete mobilization of the maxillary
segments, gentle rotation of the fine straight
osteotome results in a symmetric mobility and
separation between the maxillary central incisors.

25. An expansion device
is activated to expand
the maxilla
The osteotome is
driven posteriorly
to the midpalatal
suture.

26. Step 6: Wound Closure
All wounds are irrigated free of debris and closed using
30 polyglycolate sutures for the buccal vestibular and
midline incisions. The palatal incision is closed using
40 polyglycolate sutures in horizontal mattress fashion.

27. Step 7: Activation of the Expander
The Hyrax expander is seated using a glass ionomer cement, and the expander is activated
with one or two quarter turns to make sure activation occurs without resistance.

28. Depending on the surgeon’s preference and experience, the latency period can be eliminated
or can last up to 5 days. Special consideration is required for
patients with very little interseptal bone radiographically and those with thin gingival papilla
between the maxillary central incisors. When less than ideal
periodontal support is a factor, a longer latency period and slower activation may be more
beneficial than immediate activation and the regular expansion rate of 1 mm per day.

29. Note: If a patient has an expander that was cemented in place before surgery and the
surgeon decides not to make the palatal osteotomy, steps 3, 4, and a
cementation of the Hyrax expander can be omitted.

31. The expansion (distraction osteogenesis) is started 5 to 7 days postop to let the blood
clot organize itself into a soft callus. The distraction is done at the rate of 0.5 mm per
day until the desired dimension is obtained. In the image on the opposite side, taken at
the last day of expansion, notice the space of about 10 mm between both central
incisors. The separation between both incisors indicates that an adequate disjunction of
both hemimaxillas was performed. This freshly created space between both incisors will
close progressively while the gingival fibers, which are stretched during the expansion,
will go back to their normal size. Since they are attached to teeth by cementum, the teeth
will then move into this empty space. The installation of brackets will complete the
closing of the diastema.

32. A typical postoperative schedule looks like this:
•5 days appliance is activated for first time, instructions are given for you to activate
the appliance.
•1 week later the space that is being created between your two front teeth is checked
and the bite is checked.
•After another week the separation of teeth and the bite are checked one more time
and activation is stopped.
•You return to the orthodontist for a check.
•The appliance remains in place for 3 months without further activation.
•Orthodontic treatment is then resumed.

33. Alternative Technique:
Pterygoid Disjunction and Unilateral SARPE
At the surgeon’s discretion, a curved
osteotome may be used to separate the
pterygomaxillary junction. A fine straight
osteotome can be used
to ensure proper bony separations at the
piriform rim and the lateral and posterior
walls of the maxilla

34. If the patient has a unilateral transverse
maxillary deficiency, unilateral SARPE can
be used. A vertical interdental
osteotomy is made at the anterior border
of the segment to be expanded, using a
spatula osteotome driven to the
midpalatal suture. A horizontal buccal
osteotomy is made to connect to the
vertical osteotomy.
The remaining steps are the same as for
bilateral SARP

35. Avoidance and Management of Intraoperative Complications
Adequate mobilization of the maxillary segments is crucial to the success of unimpeded,
symmetric bony expansion. Failed expansion and a subsequent
return to the operating room can be a great distress to all parties; therefore, it cannot be
overemphasized that adequate mobility and confirmation of device
activation before the completion of surgery are of prime importance.

36. Moreover, the midline cut between the maxillary central incisors should be made with the
utmost care to ensure adequate separation within the interseptal bone without jeopardizing the
viability of root structure. Use of an ultrafine spatula osteotome
may be considered, especially when the interseptal bone between two roots is of minimal
thickness. Asymmetric and/or inadequate expansion is reported to
be the most common surgical complication (13.3%), whereas gingival recession is the most
frequent dental complication (8.3%). Fortunately, a devastating
periodontal defect that results in loss of teeth is reported to be rare and is seen less often than
in segmental Le Fort I osteotomies

37. Postoperative Considerations
SARPE may result in complications such as bleeding, infection, buccal tipping of posterior teeth,
gingival recession, attachment loss in the midline papilla
between the maxillary central incisors, oronasal fistula, palatal tissue necrosis, expansion failure,
unintended asymmetric expansion, and pain. When the
palatal incision is made, the patient must be given sinus precaution instructions,
such as to refrain from forceful nose blowing. An oronasal fistula is rare even
with a midpalatal osteotomy, and it tends to close spontaneously without further surgical repair.
A small trickle of nose bleeding is common after surgery, but
significant bleeding should be managed with the placement of nasal packs, proper control of
blood pressure, and judicious injection of a local anesthetic with vasoconstrictor.

38. Swelling typically is minimal to moderate. The patient is instructed, preferably at the presurgical
visit, in the proper use of the activation key and
the appropriate activation schedule. At the conclusion of the expansion schedule,
the device should be left in place for approximately 12 weeks as a retention
device. It typically is not necessary to place a ligature wire through the key hole, although this is
recommended by some surgeons.