Facemask Therapy with Miniplate Implant Anchorage

Dr yasser basshir
Under supervision of Dr Maher Fouda

INTRODUCTION
The bone anchors are used to increase orthodontic
anchorage in the anterior or posterior region of the
upper and/or lower jaw. A 2 or 3 holes titanium mini
plate is fixed by monocortical mini screws. The SAS is
comprised of bone plates and fixation screws. The plates
and screws are made of commercially pure titanium that
is biocompatible and suitable for
osseointegration. The anchor plate
consists of the three components, the
head, the arm, and the body.

The head component is exposed intraorally and
positioned outside of the dentition so that it does not
interfere with tooth movement. The head component has
three continuous hooks for attachment of orthodontic
forces. There are two different types of head components
based on the direction of the hooks.

. The arm component is transmucosal and is available in
three different lengths—short (10.5 mm), medium (13.5
mm), and long (16.5 mm) to accommodate individual
morphological differences

ORTHODONTIC INDICATIONS
1 Distal movement of the anterior segment in premolar
extraction cases.
2. Distal movement of the posterior and anterior
segment in non-extraction cases.
3. Mesial movement of posterior teeth.
4. Intrusion of a single tooth or a group of teeth.
5. Uprighting of mesialised lower second and third
molars.
6. Preprosthaetic orthodontics.
7. Loss of dental anchorage because of periodontal
diseases.
8. Orthopaedic intermaxillary tractions.

CONTRA-INDICATIONS
Unhealthy soft and hard tissues in implant region, poor
dental hygiene.

Types of incisions used in mini-plates fixation
- Horizontal incision.
- Vertical incision.

- at the zygomatic buttress of
the maxilla.
- nasal process of the maxilla
Anatomical sites for mini-plates placement

molar region of the mandible
canine region of the mandible

The zygomatic buttress and the canine region of the
mandible are the anatomical sites recommended for the
majority of the orthodontic applications.

SURGICAL METHOD FOR IMPLANT PLACEMENT
Incision is the most important part of the surgical
pro¬cedure. The correct location of the incision is
decided by digital palpation. By using the index finger,
the zygomatic buttress is palpated, and the incision is
made along the buttress in a vertical or horizontal
direction. In vertical direction, the lower border of the
incision is at the intersection of the attached and the
mobile gingiva, and the total length is no longer than 1
cm.

STEP-BY-STEP PROCEDURE
In the maxilla an L-shaped incision is made with
anterior convexity. The vertical part of the incision (1) is
made ± 1 cm mesial from and parallel to the infra-
zygomatic crest and up to 2 mm below the muco-
gingival boarder. The incision is extended distally (2)
with a horizontal incision 2 mm below and parallel to
the muco-gingival boarder.

The mini plate is slightly bended to obtain good contact
to the cortical bone. The bending should be limited to
the region between the holes in the mini plate. The
connection between the mini plate and the neck should
be slightly bended in the opposite direction to ensure
good contact between the lower part of the neck and the
alveolar bone.

The first screw is not completely fixed in order to
allow some rotation of the mini plate. The lower
hole is drilled and the mini screw is inserted,
followed by the upper one and all are fixed for a
strong stable retention.

After rinsing with saline solution, closure is obtained
with 4/0 self resorbing sutures. The mucoperioteal flap is
positioned by the first suture just anterior from the neck
of the bone anchor. Additional sutures are placed until
good closure is obtained. The fixation unit should be
oriented parallel to the alveolar bone with the blocking
screw facing to the front.

In the mandible a horizontal full thickness incision is
made into the gingival sulcus along the marginal bone
starting in front of the second premolar extending
mesially and including the distal papilla of the canine.
Just before the lowest point of the gingival margin in
front of the canine the incision is continued vertically
and slightly forward.

The bone anchor is positioned parallel to and between
the roots of the canine and the first premolar. The neck
should penetrate the soft tissues exactly at the level of
the vertical incision and 2 mm above the muco-gingival
boarder throughout attached gingiva. The first hole is
drilled in the inter-radicular space between the canine
and first premolar at the level of the roots apices.
The first screw is inserted but not completely fixed to
allow some rotation of the mini plate. The second screw
is inserted in the mandibular body and both are fixed for
a strong stable retention.

After rinsing with saline solution, closure is obtained in
one or two planes with 4/0 self resorbing sutures. Sutures
are placed through both papilla and along the vertical
incision.

RECOMMENDATIONS FOR THE ORTHODONTIST
• To reduce the risk for infections the placement of the
bone anchor should never be combined with extractions
of teeth.
• Removal of the remaining stitches and oral hygiene
instruction with toothbrush 10 days after surgery.
• Continuous orthodontic lading is recommended 2
weeks after surgery. Therefore both arches should be
orthodonticaly leveled before the placement of the bone
anchor. The first month light forces are used.

• The orientation of the fixation unit can be slightly
changed by finger pressure. Local anaesthesia is not
needed.
• The bone anchor should be removed when there is no
more need for skeletal anchorage.

COMPLICATIONS
- Development of Inflammation
Inflammation may develop in any phase of treatment. In
such a case, if the implant is not mobile, force
application must be stopped and antibiotic treatment
started, supported with bactericidal mouthwash. The
healing period is about 15 days. Force application can be
restarted when healing is complete, provided the
implant is not mobile, which is unlikely.

- Soft Tissue Impingement on Palate
If the palatal bars are not constructed far enough from
the palate, they may impinge on the palatal mucosa
during later stages of the dentoalveolar impaction.
Bac¬tericidal mouthwash may be used if the impaction
isompleted and the appliance is to be removed. If
con¬siderable impaction remains to be performed, the
appli¬ance should be replaced.

PATIENT INSTRUCTIONS
• Ice application immediately after surgery to reduce
swelling of the soft tissues.
• Antiseptic mouth rinsing and gently brushing the
region of the bone anchor the first week after surgery.
• Appointment with the orthodontist 10 days after
surgery to remove the remaining sutures and for
hygiene instruction.
• Appointment 2 weeks after surgery to start
orthodontic loading.
• The patient should not touch the bone anchor with his
tongue. These intermittent forces may be responsible for
the loosening of the bone anchor some weeks after
surgery.

Case report
Facemask therapy with miniplate implant anchorage
in a patient with maxillary hypoplasia

An 11-year seven-month-old Chinese boy in late mixed
dentition was seen in the Department of Orthodontics,
School of Stomatology, Peking University, Beijing, China.
Extraoral examination revealed that the maxilla was
retrognathic and the mandible was slightly prognathic.
Intraoral examination revealed an anterior and posterior
crossbite with a reverse overjet of 4 mm.

The molars were in class III relationship on both sides.
There was no crowding in both maxillary and
mandibular arches. Temporomandibular joint function
was normal.
Cephalometric analysis indicated a moderate skeletal
class III malocclusion due to both maxillary retrusion
and mandibular protrusion. The mandibular plane was
tilted 30.72° to S-N plane.

Treatment plan
The patient and parents were concerned about
dentofacial appearance. Treatment option was to use a
facemask combined with fixed appliance to correct the
anterior and posterior crossbite and improve facial
esthetics.
The patient and parents were informed
that the treatment plan did not
eliminate the possibility of
orthognathic surgery later. The
unfavorable growth of the jaws
during or after treatment might
necessitate a surgical treatmen
plan. The use of miniplate implant
as anchorage for maxillary protraction was suggested
and the patient and parents agreed.

Treatment progress
Miniplate implant placement
Titanium miniplates were implanted by an experienced
oral surgeon. After mouth rinsing for 3 minutes with
0.2% chlorhexidine gluconate, under local anesthesia, a
mucoperiosteal incision was made at the labial vestibule
between the upper lateral incisors and canines on both
sides.
Miniplates were placed on the lateral nasal wall of maxilla.

The mucoperiosteal flap was then elevated, and the
surface of the cortical bone at the apical region of lateral
incisors and canines was exposed. An appropriate length
of I-shaped miniplate (plate thickness 1 mm, 3 holes)
was selected and fixed in position with self-tapping
screws (diameter 2 mm, length 7 mm), with the head
exposed to the oral cavity from the incised wound.

Care was taken to adjust the angle between the head and
the body of the plates so that the head portion would not
apply pressure on the attached gingiva. The incisions
were finally closed and sutured with absorbable thread
around the miniplate. This patient showed mild facial
swelling for a week after the operation. It was necessary
to take antibiotics and brush carefully

Maxillary protraction appliance design
A month was allowed for healing before application of
force to the miniplates. After the month, the clinical
evaluation for the patient included an assessment of
plate mobility and infection. If nothing was abnormal,
maxillary protraction was started. First, thread a
segment of brass wire through the hole in the head of
miniplate. Second, a ganoid composite resin ball
(diameter 2−3 mm) was
made at top of brass wire.
The ball
was used for protraction
hook.

A protraction force of 450 g per side at first, 500−600 g
per side after one month with an anteroinferior force
vector 30° to the occlusal plane, was applied from the
composite ball in anchor miniplates to the facemask by
using elastic modules. The patient was instructed to
wear facemask at least 10 hours a day and prolong the
wearing time as much as possible.

Traction was continued for 6 months until enough
forward movement of the maxilla had been achieved to
improve the midface esthetics. After maxillary
protraction, the miniplate implant was removed
under local anesthesia, then fixed appliance was
bonded.

Treatment result
The application of protraction force from a facemask to a
miniplate resulted in a significant improvement in facial
esthetics and the maxillo-mandibular jaw relation.
SNA was changed from 79.89° to 82.53°, SNB
angle from 84.16° to 81.67°, ANB angle from −4.27° to
0.86°, Wits from −10.18 mm to −2.66 mm, A-NP distance
increased by 5.48 mm, mandibular
plane angle increased by 2°, while
the change of U1/SN was not
significant.

Maxillary protraction with miniplates providing
skeletal anchorage in a growing Class III patient

The patient, an 8-year-old girl with a chief concern of
“my bite is not right.”
Clinically, she had a concave facial profile, and acute
nasolabial angle, and a protrusive mandible.

Intraorally, she had an anterior crossbite and a low
anterior tongue posture. The maxillary right first
deciduous molar and left second deciduous molar had
exfoliated prematurely, and midarch crowding was
noted on the dental casts and panoramic radiograph.
The cephalometric radiograph and tracing showed
a skeletal Class III malocclusion with maxillary
deficiency, mandibular prognathism (ANB, –2.2), and
a normal mandibular plane angle (FMA, 23).

The maxillary incisors were proclined (U1 to FH, 109),
and the mandibular incisors were retroclined (IMPA, 86),
compensating for the skeletal malocclusion. There was
no family history of mandibular prognathism.

TREATMENT PROGRESS
Phase 1 treatment was started at age 8 years 4
months with a maxillary removable appliance to regain
space lost from the early loss of the deciduous molars.
After 6 months of observation, a surgical miniplate was
placed. Local infiltration anesthesia was administered to
the maxillary left and right buccal vestibular areas after
surgical disinfection.

A vestibular incision around the canine area was
performed. After an atraumatic subperiosteal dissection
to the infrazygomatic crest, a curvilinear miniplate was
adapted, bent to the zygomatic buttress’s bony surface,
and fixated with 3 self-tapping miniscrews per side.

From our experience, at least 3 to 4 screws should be
placed to resist the maxillary protraction force of about
300 to 400 cN per side. Screw placement should be in a
posteriorsuperior direction to prevent damage to the
premolar tooth follicles. The end of the miniplate
entered the oral cavity between the canine and first
premolar area in the keratinized attached gingiva to
prevent gingival irritation. The oral portion of the
miniplate was modified
into a hook for elastic
traction.

Maxillary protraction was started 2 weeks after
placement of the miniplates, with a force of 300cN per
side applied 12 to 14 hours per day. Within 10 months
of treatment, a three quarters premolar width Class II
molar relationship was established. Thereafter, the
patient’s wearing of protraction headgear was limited
to nighttime only as a retainer for 10 months. The plates
were removed after the facemask
treatment.

A mucoperiosteal incision and a subperiosteal dissection
were performed to expose the miniplate. The
monocortical screws were removed first, and the
miniplate was then detached because often new bone is
deposited next to the plate. The surgical site was then
closed and sutured.
Progress records taken at age 10 years 7 months showed
favorable growth between the maxilla and the mandible,
and the malocclusion could be camouflaged by
orthodontic treatment.

The patient was treated with fixed appliances for 18
months to establish a good molar relationship and
correct the midline discrepancy. A maxillary
circumferential retainer and a mandibular lingual fixed
retainer were placed after appliance removal. The
patient was instructed to wear the retainer at night for 10
to 12 hours.

TREATMENT RESULTS
14 months after protraction headgear treatment. The
malocclusion was overcorrected to a Class II molar
relationship to compensate for future excessive
mandibular growth.

Superimposition of pretreatment and posttreatment
cephalometric tracings showed 8.1 mm of forward
movement of A-point (A-point to NtFH) and 3.3 of
counterclockwise tipping of the palatal plane .
The ANB angle changed from –2.2 to 1 6.7.

The SNO, or angle between the anterior cranial base and
orbitale, changed from 63 to 70. Labial tipping of the
maxillary incisors and lingual tipping of the mandibular
incisors, which are typically observed after tooth-borne
protraction, were not seen with the miniplates.

after phase 2 fixed appliance treatment at age 12 years 6
months. The ANB angle was reduced from 6.7 to 3.9,
indicating normalization of the jaw relationship after
overcorrection in the phase 1 treatment. Class I canine
and molar relationships were obtained, and overjet and
overbite were returned to normal after phase 2
treatment.
Intraoral photographs near the end of phase 2 fixed appliance
treatment.

- patient at age 14 years 9 months, 27 months after the
removal of the orthodontic appliances. During the
retention period, the maxilla and the mandible showed
relatively harmonious growth, maintaining an ANB
difference of 3. The angle of convexity was reduced from
7.4 to 5.4.

Superimposition of the posttreatment and postretention
cephalometric tracings showed continuous dental
compensation to the skeletal discrepancy was observed
with proclination of the maxillary incisors and slight
retroclination of the mandibular incisors.

Orthopedic Traction of the Maxilla With
Miniplates: A New Perspective for
Treatment of Midface Deficiency
J Oral Maxillofac Surg 67:2123-2129, 2009

Summary of Cases and Diagnosis
Three girls (aged 10 to 11 years) presenting with a
severe skeletal Class III relationship with a maxillary
deficiency and concave soft tissue profile were treated
according to the same treatment plan. Two of them had
an anterior crossbite without anterior shift of the
mandible (cases 2 and 3). One had an edge-to-edge
incisor occlusion in centric relation, with a forward
posture into maximum intercuspation (case 1).

Pretreatment cephalometric evaluation of the 3 cases
showed a skeletal Class III relationship with hypoplasia
of the maxilla combined with a normal or increased
mandibular size and normal or slightly decreased
vertical dimensions. The patients’ upper incisors were
proclined or retroclined, and the lower incisors were
normal or proclined.

Treatment Plan
The 3 patients were treated exclusively by intermaxillary
traction between miniplates placed in the
maxilla and in the mandible, in combination with a
bite plane to jump the crossbite.

Treatment Progress
Four orthodontic miniplates were inserted into the
infrazygomatic crests and between the canine and lateral
incisor or between the canine and first premolar in the
mandible, on both the right and left sides. Surgery was
performed with patients under general anesthesia (cases
1 and 2) or local anesthesia (case 3). The miniplates were
fixed to the bone with 2 or 3 titanium screws (2.3 mm in
diameter and 5 mm in length) after predrilling with a
1.6-mm-diameter bur, as previously described.

Three weeks after surgery, maxillomandibular elastics
were attached between the upper and lower miniplates
on each side, applying a force of 100 g per side. The
patients were asked to replace the elastics once a day
and to wear them 24 hours per day. After 1 month (case
1) or 2 months (cases 2 and 3), a removable bite plane
was placed to eliminate the occlusal interference in the
incisor region. At this time, the elastic force was
increased to 200 g per side.

After 7 months (cases 1 and 2) or 12 months (case 3) of
orthopedic traction, the bite plane was removed. The
traction was maintained full time for a total period of 12
months (cases 1 and 2) or 16 months (case 3). No local
infections were observed around any of the miniplates.
They remained stable throughout treatment. During the
follow-up period after the active treatment, the patients
wore the elastics at night for retention.

Results
The anterior crossbite was corrected in each patient.
Their soft tissue profiles considerably improved, with
anterior displacement of the whole midface (infraorbital
ridge, nose, and upper lip), reducing the paranasal
concavity. Almost no anterior displacement of the lower
lip and chin was observed at the end of the traction,
leading to an improvement of the relationship between
the upper and lower lip. The tip of the nose moved
slightly upward.

Lateral cephalograms were taken at the beginning
of treatment, at the end of orthopedic treatment, and
at follow-up 11 to 38 months later.
Cephalometric evaluation between the beginning
of treatment and end of treatment showed a marked
increase of ANB, Wits, and facial convexity (G=-Sn-
Pg=) values in all 3 cases . No rotation of the
mandible was observed in cases 1 and 3, whereas a
slight clockwise rotation was seen in case 2; there
was a slight counterclockwise rotation of the maxilla
in all patients. No major changes occurred in the
upper incisor inclination, whereas the lower incisors
were proclined. During the follow-up period (from
end of treatment to 11 to 38 months later), the Class
III correction was maintained.

Treatment ofMaxillary Deficiency by
Miniplates:
A Case Report

The patient was an 11-year-old boy who was referred
for treatment of maxillary deficiency. He had no medical
problems, and there were no signs of
temporomandibular joint dysfunction. The patient had a
skeletal Class III malocclusion and maxillary deficiency.
His parents had no Class III characteristics.

The facial photographs showed a Class III appearance
with a concave profile because of maxillary deficiency.
The pretreatment intraoral photographs and dental casts
showed Class III relationship of the central incisors and
anterior crossbite. The patient had a Class III molar
relationship on the right and Class I on the left side.
Cephalometric analysis confirmed the Class III skeletal
pattern.
Treatment Objectives
The treatment objectives for this patient were to
(1) correct the deficient maxillary arch, ideally by
forward
positioning of the maxilla;
(2) obtain an ideal overjet and overbite;
(3) correct the anterior crossbites.

Treatment Alternatives
Extraoral appliances, such as protraction facemask, Class
III functional appliance, any modified maxillary
protraction devices, and orthognathic surgery, were
considered as alternative treatments for the correction of
this Class III malocclusion. However, the patient refused
the use of extraoral appliances and major surgery.
Therefore, in this case, it was decided to use miniplates
to protract the maxilla by application of Class III elastics.

Treatment Progress
Plates for Orthodontic Anchorage were placed under
local anaesthesia in the canine areas of the mandible by a
maxillofacial surgeon. The ideal position for miniplates
insertion was evaluated by using a panoramic
radiograph in order to avoid damage to the roots of the
adjacent teeth and mental foramen.

A tightly fitting and well-retained upper removable
appliance was fabricated with two Adams clasps on the
upper first permanent molars. Each of the Adams clasps
had a loop which was used for retaining the elastics. A
labial bow was also used on the anterior teeth for
retention. A maxillary posterior bite plate was used to
disclude the upper and lower jaws.

Orthodontic latex elastics (3/16 heavy size—Unitek
Elastics) were connected from the hooks of the
miniplates to the Adams clasps of the removable
appliance to generate approximately 500 g of anterior
retraction. The patient was instructed to wear the
appliance full-time except for eating, contact sports, and
tooth brushing; he was also told to change the elastics
every day. In order to retain these elastics, the Adams
clasps on the molars were bent to form loops.

Treatment Results
After 10 months of active treatment a positive overjet
and Class I buccal segments were achieved and the
anterior crossbite was corrected. The posttreatment
cephalometric radiograph tracing showed a favourable
increase of 5.1◦ and 4.4◦ in the SNA and ANB angles,
respectively.

The pre- and posttreatment cephalometric
superimposition on the anterior cranial base is shown in
this Figure.

Skeletal Anchorage for
Orthopedic Correction
of Growing Class III Patients

Bong-Kuen Cha and Peter W. Nga(2010)
Investigators have shown that maxillary protraction
with palatal expansion therapy is an effective method
for treatment of Class III patients.
Although intervention in the primary or early mixed
dentition may provide a better orthopedic response,
treatment started in the late mixed or early permanent
dentition can elicit reasonable orthopedic response when
the circummaxillary sutures are still patent.

One of the limitations in maxillary protraction with a
conventional tooth-borne type appliance is the loss of dental
anchorage, especially in the dynamic period of the mixed or
late permanent dentition.
Many investigators have attempted to design an absolute
anchorage system for maxillary protraction. A priori
ankylosed teeth, intentionally ankylosed maxillary
deciduous canines, or osseointegrated titanium implants
can be used as an absolute anchorage for protraction
treatment.

However, the use of ankylosed teeth limits the orthopedic
treatment to only the early mixed dentition period.
Skeletal anchorage by the use of miniscrews or
miniplates are gaining popularity as a source of absolute
anchorage in contemporary orthodontics.
Kuen Cha.B and Nagan.P quantified and compared the
effects of maxillary protraction using surgical miniplates
as anchorage to maxillary protraction in conjunction with
an expansion appliance (rapid maxillary expansion
[RME]).

Methods
Two treatment modalities for the correction of Class III
malocclusions in growing patients were compared by
treating 2 groups of patients. One group of 25 patients (16
girls and 9 boys) was treated with a facemask combined
with a bonded RME and a second group of 25 patients
(15 girls and 10 boys) treated with a facemask employing
a surgical miniplate as anchorage.

Schematic illustration shows a curvilineartype miniplate
fixed with 3 self-tapping miniscrews on the zygomatic
buttress area. The end of the miniplate was exposed between
the canine and first premolar area, located over the
keratinized attached gingiva to prevent gingival irritation.
Protraction force is approximately 300-400 gm per side and
the line of force is 30° to the occlusal plane.

The placement of miniplates was carried out under local
anesthesia.
The anchor plates were placed at the zygomatic buttress
area to avoid damage to the underlying developing tooth
buds of the permanent teeth
Protraction force is most often applied after 3 or 4
weeks of healing.
The facemask was inserted after maxillary expansion or
placement of the miniplate the total force applied was
400 g/side.

Patients in both treatment groups were instructed to
wear the appliance for at least 14-16 hours a day.
Posttreatment cephalometric radiographs were taken
when a normal dental relationship was obtained with
an overjet of 2-3 mm.
The average treatment time in miniplate group was 9.2 2.4
months and the RME group 8.5 2.4 months.

Pretreatment records of 11-
year, 4-month-old male
patient (THC) with Skeletal
Class III malocclusion and
anterior crossbite, crowding.
The concave profile is
shown in the lateral
photograph.

Patient (T.H.C.) treated with a face mask with the
skeletal anchorage system for 11 months.

Facial and intraoral
photographs of patient T.H.C.
after 10.5 months of
protraction treatment. After
protraction with miniplate,
Class III malocclusion
has been corrected.

Pretreatment records
of a 10-year, 8-month-
old female patient
(J.E.C.) with skeletal
Class III malocclusion
and anterior crossbite.
Loss of space for
upper right second
premolar attributable
to mesial movement
of right first molar.
Showing concave
profile in lateral
photograph.

Facial and intraoral photographs of J.E.C. during the maxillary
protraction with miniplates. Pendulum appliance was used
simultaneously to gain space for the right second premolar.

Results
No significant differences were found between the 2
groups in dentofacial morphology except for the lower
incisal inclination (IMPA was 80.68° for the miniplate
group and 85.69° for the RME group, P 0.05).
Skeletal Changes
The anterior and posterior cranial base lengths were
found to increase significantly in both treatment groups.
However, no significant differences were found between
the 2 groups.

The measurement SNA was found to increase
significantly by 3.29° in the miniplate group and 2.22° in
the RME group. The changes were significantly greater
in the miniplate group.
Similarly, the measurement A to perpendicular to FH was
found to increase by 3.42 mm in the miniplate group and
2.13 mm in the RME group . The changes were also
significantly greater in the miniplate group .

With treatment, the mandible was found to rotate
downward and backward in both treatment groups.
The mandibular plane angle (FMA) was found to
increase significantly in both the miniplate group
(1.01°) and the RME group (1.74°).
A greater increase in the forward position of the maxilla
was found in the miniplate group compared with the RME
group. Such a difference can be explained by direct
transmission of the orthopedic force to the maxillary
sutures in the miniplate group.

The placement of miniplates in the zygomatic buttress
area is closer to the center of resistance of the maxilla
which is usually located half way between the infraorbital
rim and the mesial buccal cusp of the maxillary molars.
In contrast, orthopedic force in the RME group is directed
along the occlusal plane rather than at the center of
resistance of the maxilla. Consequently, bone remodeling
occurs not only at the circummaxillary sutures but also
within the periodontal tissues.
Palatal expansion has been shown to disarticulate the
maxilla and initiate cellular response in the suture,
allowing a more positive reaction to protraction forces.

The maxillary first molars were found to move backward
0.46 mm compared with a forward movement of 3.26 mm
in the RME group.
Vertically, significant extrusion of the maxillary first
molars were found in both treatment groups.
The maxillary incisors were found to move forward by
0.11 mm in the miniplate group compared with 1.83 mm
in the RME group.
Dentoalveolar changes

Three-dimensional analysis of
maxillary protraction with
intermaxillary elastics to
miniplates

Heymann et al (2010)said that the Protraction face-mask
therapy or reverse-pull headgear (RPHG) is perhaps the
most common approach for early treatment of young Class
III patients with maxillary deficiency
This approach is limited in that the forces are applied to
the teeth, resulting in uncertain skeletal and often
unwanted dentoalveolar effects.

For satisfactory clinical improvement, excellent
compliance with an extraoral appliance is required and
treatment regimns recommended wearing the appliance
for 12 to 16 hours per day for 9 to 12 months.
most investigations have described some limited
orthopedic effect on the maxilla (2–3 mm of advancement
on average), clockwise rotation of the mandible, and
dentoalveolar changes consistent with treatment of Class
III malocclusion (proclination of maxillary incisors and
retroclination of mandibular incisors).

Long-term follow-ups of maxillary protraction indicate
a 25% to 33% chance of relapse to negative overjet after
all mandibular growth is complete.
Since dentoalveolar changes tend to be the most prone
to relapse, it seems advantageous to minimize the
dentoalveolar effects while maximizing the orthopedic
correction.
Heymann et al used. An alternative treatment of early
Class III with intermaxillary elastics from a temporary
anchorage device that might permit equivalent
favorable skeletal changes without the unwanted
dentoalveolar effects.

MATERIAL AND METHODS
Criteria for participation in the study were 9–14 years of
age at the start of treatment, skeletal Class III due
primarily to maxillary deficiency (determined by clinical
examination including profile evaluation), Class III dental
occlusion determined by the permanent first molars or
overjet ≤0 mm, and sufficient dental development, to
avoid injury to unerupted mandibular permanent canines
during surgical placement of the miniplates.

Six consecutive patients (3 boys, 3 girls; ages, 10–13
years 3 months) with Class III occlusion and
maxillary deficiency were treated by using
intermaxillary elastics to titanium miniplates
All 6 patients were at prepubertal cervical vertebral
maturation stages.
In the surgical procedure, 4 miniplates were placed in
each patient—1 in each infrazygomatic buttress of the
maxilla and 1 in the anterior mandible between and
inferior to the left and right permanent lateral incisor
and canine.

The modified titanium
miniplates incorporated an
intraoral attachment with a
locking fixation screw to allow
customizable traction hooks
In all sites, the miniplates were placed with the
attachment arm exiting through attached tissue at or near
the mucogingival junction.

The miniplates were loaded 3 weeks after surgery. One
elastic was placed on each side to give vectors of force
downward and forward for the maxilla and backward and
upward (counterclockwise) for the mandible. The patients
were instructed to wear elastics 24 hours per day.
The elastics were chosen to provide an
initial force of approximately 150 g to
each side, increased to 200 g after 1
month of traction and to 250 g after 2
months. The forces were measured
with the patient in maximum
intercuspation by using a Correx force
gauge

All patients in this study showed a negative change on
the anterior surfaces of the condyles and a positive
change on the posterior surfaces, suggesting that there
was at least some posterior repositioning of the
mandible.
All 6 patients had a positive change at the surface region
that encompassed the upper lip as the underlying hard
tissues of the maxilla changed.
In 5 of 6 patients, the entire nasal complex appeared to
rotate anteriorly and superiorly, suggesting that the forces
from the TADs were dispersed widely through the
nasomaxillary complex.

It has been well documented that facemask treatment
results in an increase in maxillary incisor angulation and a
decrease in mandibular incisor angulation.
Dentoalveolar effects observed in this study tended to be
in the opposite directions, possibly as a result of
alteration of soft-tissue equilibrium forces.
The use of CBCT for this study allowed the treatment
changes to be visualized and described in greater
detail than with 2-dimensional (2D) imaging alone.

Keinprasit et al (2010) treated a case of severe
maxillary hypoplasia in a 21 years old male Thai
patient with a complete unilateral cleft of primary
and secondary palates by internal distraction
osteogenesis for maxillary advancement.

Case history:
The patient was a 21 years old Thai male with a
repaired right complete unilateral cleft lip and palate
with severe Class III malocclusion and very severe
midfacial hypoplasia.
The cleft lip was repaired at the early infant period, and
the cleft palate at four years of age. Secondary alveolar
bone grafting was completed when he was 19. There
was velopharyngeal insufficiency that produced
hypernasal speech.

Extraoral examination showed a symmetrical
dolicofacial type with a concave profile and flat
paranasal areas due to underdeveloped maxilla. The
mandibular plane was steep.

Intraorally, there was a pegged-shape lateral incisor
in the lateral segment next to the cleft area.
The occlusion was Class III with total crossbite and 6
mms negative overjet.
There was an incomplete anterior bite with 0% vertical
overlapping.
The lower dental midline was deviated 1 mm to the left.

Both maxillary first premolars and left maxillary first
molars were missing with residual spaces.
There was 3 mms crowding in the anterior region.
Mandibular first molars were missing with the second
molars drifted into the spaces.

Cephalometric analysis showed a
skeletal Class III relationship
(ANB-6.5°) due to retrognathic
maxilla (SNA 82.5°, A-Nperp -6
mms) and prognathic mandible
(SNB 89°, Pog-Nperp +3 mms).
Open vertical skeletal relationship
(PP-MP 29.5°) was presented due to
anterior inclination of palatal plane
(SN-PP 1.5°) and opening rotation
of mandibular plane (SN-MP 31°),
causing decreased facial index
(73%).

Treatment:
The treatment plan was orthodontic treatment combined
with maxillary distraction osteogenesis to correct skeletal
discrepancy and improve facial appearance.
Predistraction orthodontic treatment to level and align
the dentition and close all edentulous spaces was
planned.
The objective of maxillary distraction is to advance and
anteriorinferiorly reposition of the maxilla, so that
mandibular set back would not be necessary to reduce
its prognathism.

After the distraction, treatment would be completed by
finishing orthodontics.
The treatment was begun in early 2004 for arch leveling,
aligning, space closures and inter-arch coordination.
Predistraction orthodontic preparation was completed in
2007

The surgical approach for distraction was similar to a Le
Fort I osteotomy.
Circumvestibular incision and complete osteotomy
were performed and the maxilla was then down-
fractured.
The distraction vector was oblique to the occlusal plane
to move the maxilla anteriorly and inferiorly. The devices
were activated to test their function and the mobility of
the released bone segment and then returned to the
starting positions.
The surgical wound was closed with the two activation
ports exited through the mucosa into the buccal
vestibules.

The device activation was started after a 5 days latency
period.

Both Synthes® screws were activated by oral surgeons
at a rate of 0.25 mm twice a day for 2 weeks and then
0.5 mm once a day for another week until 8 mms
maxillary advancement with 1 mm positive overjet were
obtained.
After 4 months of complete bone consolidation, the
distractors were removed and postdistraction orthodontic
treatment was started. Intermaxillary Class III elastics
were applied to produce 3 mms incisor overjet for
overcorrection and prevention of anterior crossbite
relapse. Satisfactory occlusion was achieved. There was
no longer any posterior crossbite.

Retention period photographs, at 20 months after orthodontic
appliance removal

Baek et al (2010) reported a case report of a patient was a
12 year 1 month old girl with CP only. She presented with
concave facial profile, anterior crossbite (29 mm overjet), and
anterior open bite (22 mm overbite). Cephalometric analysis
showed skeletal Class III malocclusion with maxillary
hypoplasia.

(ANB, -5.4; A to N perp, -3.4 mm), steep mandibular plane
angle (FMA, 32.7u), and a skeletal age after the pubertal
growth spurt according to the cervical vertebrae maturation
index (CVMI, stage 4). Her condition was one of the
contraindications for conventional facemask therapy.

FM/MP therapy was started 4 weeks after placement
of the miniplates according to the protocol.
During protraction, the fixed appliances were placed
to align the dentition.

After 16 months of FM/MP therapy, there was significant
forward movement of the point A (A to N perp, 5.6 mm). The
ANB angle was changed from - 5.4° to 2.9°, and a Class II
canine and molar relationship, normal overbite, and overjet
were obtained. A slight counterclockwise rotation of the
occlusal plane angle (-1.8) was interpreted to mean that there
was almost no side effect such as extrusion of the upper
molars.

Although the FMA was increased 4.3, the anterior open
bite was corrected by downward and forward movement
of the maxilla. Slight labial tipping of the upper incisors
(U1 to SN, 2.0°) occurred after correction of anterior
crossbite and open bite

Orthopedic Protraction with Skeletal
Anchorage in a Patient with
Maxillary Hypoplasia and
Hypodontia

Kircelli et al (2006) presented a case report of
a 11-year-old girl was referred with a complaint of‘‘small
and separated teeth’’ and ‘‘lower jaw projection.’’ Medical
history of the patient was noncontributory other than her
parents were cousins. Furthermore, her elder brother
presented with similar complaints of maxillary hypoplasia
and hypodontia. Clinical and radiological examination
revealed severe hypodontia and microdontia. Twenty-one
of her permanent teeth were missing, whereas number 11,
21, 36, 46 existed in the dental arch and germs of the
number 15, 37, and 47 could be detected on the panoramic
radiograph.

Furthermore, microdontia existed both in her
primary and permanent dentition. The maxillary
arch was deficient sagittally and transversally, so
that there was an eight mm negative overjet and
a bilateral buccal crossbite relationship with the
lower jaw.

A depression of the midfacial structures included the
maxillary and infraorbital regions with a relative
prominence of the mandible, inadequate projection of
the nasal tip and an old face appearance with an
unesthetic smile constituted general features of the
patient . She also had nasal respiratory problems
causing mouth opening during sleep.

Three treatment options were considered for maxillary
advancement. The first option was to delay treatment
until growth has ceased and to correct the jaw
relationship by orthognathic surgery. The second option
was to apply rigid external distraction together with
complete Le Fort I osteotomy. The third option was to
try to take advantage of the sutural growth potential by
applying extraoral force with a face mask via rigid
skeletal anchors placed to the maxillary bone.
Treatment options

A titanium miniplate designed by Erverdi16 (MPI,
Tasarımmed, Istanbul, Turkey) was used as a rigid
skeletal anchor to attach the elastic orthopedic forces to
the maxilla. Multipurpose miniplates were to be placed
on both sides of the apertura piriformis and on the lateral
nasal wall of maxilla. Rapid maxillary expansion was also
planned to correct the transversal maxillary deficiency
and to disturb the circummaxillary sutures.

Because the maxillary dentition was insufficient, it was
decided to place intraosseous titanium screws (two 3 eight
mm IMF screws, Leibinger, Germany) on the palatal
bone, near the alveolar crests, to provide anchorage for the
expansion appliance. After routine surgical preparations,
patient received general anesthesia. Bilateral mucosal
incisions were made on labial sulcus between lateral incisor
and first cuspid region.

Then, mucosal flaps were carried inferiorly, the muscles
and periosteum were incised and reflected
superomedially, exposing the apertura piriformis and the
lateral nasal wall of maxilla on both sides. Once an
adequate space was achieved for miniplate placement, the
nasal mucoperiosteum was elevated. Multipurpose
miniplates were meticulously contoured to the bilateral
lateral nasal wall, and straight extensions were bent to
hook shape providing retention for face mask elastics and
projected into the oral cavity through three mm
mucoperiosteal incisions made inferiorly on the attached
gingiva.).

Subsequently, for final stabilization of the bone plates
three, 2.0 mm screws (five mm length) were placed with a
1.3 mm diameter drill under copious irrigation
Simultaneously, four intraosseous bone screws were
placed in the anterior and posterior palatal region, close to
the alveolar crests, bilaterally .After soft tissue healing,
orthopedic forces were applied.
IMF screws placed in anterior and
posterior palatal region.

Impressions and stone casts were obtained with th IMF
screws in place. The screws were blocked out with wax on the
stone model, and an acrylic plate was prepared with an
expansion screw in the midline. Appliance adaptation was
checked intraorally and then connected to the IMF screw
heads using cold curing methyl methacrylate–free acrylic
resin (Ufi Gel hard, Voco GmbH, Cuxhaven, Germany). One of
the parents was asked to activate the screw a quarter turn
once a day.
Construction of the intraosseous screw– supported
expansion appliance
Intraosseous screw–supported
maxillary expansion appliance.

An elastic force of approximately 150 g was applied
bilaterally to the miniplate extensions after the adaptation
of face mask (Leone spa, Firenze, Italy). After being sure of
the stability, the force was increased gradually to 350 g.
The direction of the force was adjusted approximately 308
to the occlusal plane, and the patient was asked to wear
the face mask full time except during meals.

The application of the orthopedic forces via elastics directly
to the anterior part of the maxillary bone by using miniplate
anchorage resulted in a remarkable improvement in the
middle face. Together with the maxillary bone advancement,
significant enhancement in the soft tissue profile revealed
improved facial esthetics. The maxilla was expanded from the
median palatal suture, and seven mm of expansion was
achieved across the buccal segments. Coordination of the
dental arches both in the sagittal and transversal planes
created improved physiological functions.

Post treatment intraoral
photographs.

Facemask Therapy with Miniplate Implant Anchorage

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