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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_4496_Библиотеки_им_академика_М_И_Перельмана
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W. Schupp et al.
With respect to the maxillary and mandibular
incisors, it would be wrong to procline the
upper incisors and recline the lower incisors.
In preparation for OGS, the upper incisors
should be reclined and the lower incisors
should be proclined. Class II—elastics can be
used for class III—decompensation [20].
For class III also: Anteroposteriorly, dental com-
pensations are removed by ideally positioning
the teeth relative to their apical bases. This
will make the malocclusion look worse presurgically, but it will unravel the true magnitude of the skeletal problem, thus allowing an
optimal correction at surgery [21].
The general rule is that orthodontic and surgical
relapses should not add up. Whenever possible, treatment should be planned so that the
orthodontic and surgical relapse tendencies
are in opposite directions [12].
Make open bite worse
In most cases, the upper incisors will need further
intrusion. The dental relapse often following
orthodontic intrusion leads to a deepening of
the dental bite and thus does not add to the
surgical relapse tendency of a possible skele-
tal bite opening.
In open-bite cases, steps within the arches are an
indication for segmental surgery. Orthodontic
leveling will be limited to the segments, and
segments will be leveled with differential
intrusion at surgery [21].
The gold standard treatment of skeletal anterior
open-bite patients is the combined approach
of orthodontic treatment and orthognathic sur-
gery. In recent years, temporary anchorage
devices (TAD) have been developed to correct
anterior open bites orthodontically. With the
introduction of TAD as an effective treatment
modality, orthognathic surgery may be avoid-
able in selected anterior open-bite patients.
This is a relatively new technique, and to date,
there remains a lack of evidence of long-term
stability of anterior open-bite closure with
TAD [8, 22].
Midline problem
The dental midline of the mandible should always
be coordinated with the center of the chin in
the pretreatment. For the dental midline of the
upper jaw, an orthodontic adjustment with the
center of the face is not necessary if an upper
jaw osteotomy is planned. In this case, the
midline correction is performed surgically as a
result of the rotation of the maxilla.
Transverse discrepancy
No orthodontic expansion should be done presur-
gically in a patient who will have surgical
expansion. Any tooth movement with relapse
potential should be avoided presurgically.
Postsurgical orthodontics will bring teeth into
position and proper intercuspation within a
reasonable time period [21].
Spaces
Some spacing is often desirable at the time of
surgery to allow extra overjet to ensure
canine seating or to allow room for postsurgi-
cal leveling without forward movement of
the lower incisors. A small degree of spacing
may also create optimal occlusal relation-
ships if the surgical outcome deviates from
the plan [12].
Pretreatment and preparation for orthognathic
surgery (OGS)
There is no universal agreement among ortho-
dontists and surgeons about the goals of orth-
odontic treatment before surgery. Some teams
prefer nearly ideal interdigitation of presurgi-
cal plaster models before proceeding, whereas
others are content to do the detailed nishing
after surgery. In general, the guiding principle
is that the teeth need to be moved sufciently
to allow the maxilla and mandible to be put in
the desired position [21].
We only prefer as much pretreatment with xed
mechanics or AO as necessary [20, 21].
Presurgical leveling allows mandibular advance-
ment with minimal clockwise rotation of the
mandibular, which helps promote horizontal
movement and chin prominence. Maintaining
the curve of Spee requires the creation of a tri-
pod occlusion on the incisors and molars at
the time of surgery, which increases the verti-
cal dimension and increases clockwise rota-
tion. That is the reason why in some cases, the
postsurgical leveling produces more desirable
vertical changes and minimizes chin promi-
nence [12].
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167
Starting treatment without deciding whether to
treat with or without surgery is generally a bad
idea [12].
In case of pretreatment with xed mechanics, the
dental arches must be blocked in the status
achieved by passive steel arches (zero arches)
with cinch back or tie back.
In case of an AO pretreatment, the last aligner is
worn until the day of OGS and must be reinserted immediately after OGS.It is advisable
to thermoform these aligners twice and hand
out one pair as a replacement. The segmentation of the maxilla is an exception. Here, the
upper jaw OGS splint must initially be left in
place. Intramaxillary elastics cannot be
attached dentally. Here, we absolutely need
IMF screws.
Surgery First
Surgery rst (SF) is an innovative surgical orthodontic approach for the correction of skeletal
deformities. In the SF procedure, the maxillomandibular relationship is corrected into skeletal
class I with a symmetrical face in the early stage
of the treatment period. Once the orthodontic surgery (OGS) is completed, postsurgical orthodontics is required to correct the transitional skeletal
class I malocclusion with the complex dental
problems these patients typically display. In
2009, Sugawara reported the rst ever SF case in
combination with the skeletal anchorage system
(SAS). The following are the major advantages
of SF compared to OF:
• The facial prole is improved in the early days
after OGS.
• The total treatment time is signicantly
shorter.
• Orthodontic decompensation is efcient and
effective because of the biological effects
derived from the natural force provided by lips
and tongue.
• Tooth movement appears to be accelerated by
the regional acceleratory phenomena.
Sugawara, Ojima, and Dan provide a new
option in SF to support those patients who voice
their preference for aligners over xed appliances
in the postsurgical orthodontic treatment stage.
This leads to a reduced treatment time with the
xed appliance. As early as possible, they switch
from xed appliance to aligner orthodontics for
detailing and nishing [23].
In patients requiring orthognathic surgery, it is
suggested that there are advantages in correcting
the skeletal and soft tissue elements as early as
possible, and to orthodontically control the occlusion postoperatively. This results in a shorter
overall treatment time due to more biologically
favorable tooth movement, more predictable
occlusal results, and better management by the
orthodontist. The clinical benets of postoperative orthodontics are outlined [24].
In a study presented by Hernandéz-Alfaro
et al., 45 patients were managed with the SF
approach. Selected cases presented symmetrical
skeletal malocclusions with no need for extractions or surgically assisted rapid palatal expansion. Periodontal or temporomandibular joint
problems and management by an orthodontist
without experience in orthognathic surgery were
considered exclusion criteria. Virtual treatment
planning included a three-dimensional orthodontic setup. Standard orthognathic osteotomies
were followed by buccal interdental corticotomies to amplify the regional acceleratory phenomenon. Miniscrews were placed for
postoperative skeletal stabilization. Orthodontic
treatment began 2weeks after surgery. Archwires
were changed every 2–3weeks. The SF approach
signicantly shortens total treatment time and is
very favorably valued by patients and orthodontists. Nevertheless, careful patient selection, precise treatment planning, and uent bidirectional
feedback between the surgeon and the orthodontist are mandatory [25].
Three-dimensional computed tomography
should be used to construct the midfacial plane
and then to assess discrepancies in the midfacial
structures as well as yaw and roll of the bilateral
facial structures. Orthognathic surgery should
be performed to improve the alignment of such
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W. Schupp et al.
discrepancies to attain a skeletal class I relationship and to attain an esthetically pleasing face.
The surgery-rst approach uses osteotomy to
solve most of the skeletal and dental problems
and to simplify postoperative orthodontic treatment by providing a treatable malocclusion for
which mostly only anteroposterior orthodontic
movement is required, with minimal transverse
or vertical orthodontic movements. Numerous
studies have documented the efcacy and longterm stability. Patients undergoing the surgeryrst approach benet from an immediate
improvement in facial esthetics, oral function,
and self- condence, with a shorter total treatment period [26].
Total treatment duration is substantially
shorter in cases of surgery-rst approach use. In
conclusion, most published studies related to the
surgery-rst approach were mainly on orthognathic correction of skeletal class III malocclusion.
Both the surgery-rst approach and orthodonticsrst approach had similar long-term outcomes in
dentofacial relationship. However, the surgeryrst approach had shorter treatment time [27].
whereas only 40% of patients undergoing bilateral sagittal split osteotomy showed improvement in symptoms and 8% of asymptomatic
patients developed new symptoms [35]. Arnett
and Gunson relate the statistical difference to
condylar torquing as a result of bicortical screws
displacing the proximal segment during xation
of bilateral sagittal split osteotomy [36].
No TMD Symptoms
If the clinical functional analysis shows no signs
of TMD, planning and subsequent treatment can
begin immediately.
TMD Symptoms Present
If TMD symptoms are found in the initial examination, therapy with an occlusal splint is initially
carried out, as shown in the algorithm, possibly
supported by manual medical therapy [3]. After
successful therapy, treatment planning can be
carried out based on the CR.
Specialties forTMD Patients
OGS is well accepted to correct dentofacial
deformities. The role of OGS in the treatment of
TMD is controversial. There are studies that
show improvement of TMD following OGS [12,
28–30]. There are also just as many studies that
show no signicant improvement or even worsening of symptoms following surgery [12, 31,
32]. It should be emphasized that asymptomatic
patients after OGS may also show symptoms of
TMD [12]. One of the reasons for this may be the
difculty in adjusting the condyle during
OGS. This seems to depend on the surgeon’s
experience [33].
An intraoral vertical ramus osteotomy will
result in an anterior and inferior displacement of
the condyle and an increase of the joint space
[34]. A study showed that 75% of patients undergoing intraoral vertical ramus osteotomy had an
improvement or resolution of TMJ pain and no
asymptomatic patients developed new pain,
Aligner Orthodontics
andOrthognathic Surgery
Orthodontic treatment with AO as part of OGS
was described by Schupp and Haubrich in 2012
[1].
A substantial number of patients require
orthognathic operations combined with orthodontic treatment. Indeed, a recent American
study suggested that of the 20% of the population
in the USA who have deviations from the ideal
bite, 2% are severe enough to be disguring and
are at the limit of orthodontic correction.
A survey of British consultant orthodontists
showed that 7% of their caseload comprised surgical orthodontic patients [17]. Nearly all of
these patients are adults. Nurminen etal. found
that 79% of the 28 patients who participated in
their study reported considerable pain from the
orthodontic appliances, and a third of the patients
rated orthodontics as the worst part of their treat-
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ment due to the appliances’ visibility, discomfort,
and length of orthodontic treatment [37].
Chang et al. demonstrated an SF approach
combined with AO (Invisalign) to treat a severe
skeletal class II malocclusion caused by mandibular retrognathism. Accurate prediction of the
nal outcome is integral to the success of SF
approach. The Invisalign ClinCheck system
facilitates precise development of virtual treatment objectives by illustrating the anticipated
nal occlusion. The aligner treatment planning
and manufacturing were done pre-SF because
minimal dental changes were expected from the
surgery [38].
Orthognathic surgery for dentofacial deformities is typically preceded and followed by orthodontic treatment. Traditionally, orthodontic
hardware is secured to the dentition to allow dental movement and stabilization. Aligner orthodontics (e.g., Invisalign) provides an esthetic
alternative, consisting of a series of transparent
trays. Its use has not been described in complex
triple-jaw orthognathic surgery. Following a
series of examinations and investigations, a set of
presurgical active and passive aligners are developed, with the latter worn in the few weeks
immediately preceding the procedure [39].
In a study by Kankam etal., 33 patients, with
a mean age of 19.99 years, were included: 13
were treated with aligner orthodontics and 20
with conventional xed appliances. No signicant difference was observed in operating time,
concurrent extraction of teeth, fat grafting, duration of hospital stay, diet advancement, and use
of narcotic analgesics between the two groups.
Nine patients had sufcient three-dimensional
images for volumetric analysis (four with aligner
orthodontics and ve with conventional xed
appliances). Postoperative edema was not signicantly different (P=0.712) when comparing conventional xed appliances (44.29±23.16cm) to
aligner orthodontics (37.36±31.19cm).
It was concluded that complex multiple-jaw
orthognathic procedures can be successfully performed in aligner patients. Perioperative and
short-term clinical outcomes are not compromised [40].
Segmental LeFort I osteotomy, a complex procedure with many mobile parts, has traditionally
required presurgical orthodontics with conventional braces, composed of brackets, bands, and
archwires. These appliances are not always
accepted by patients, particularly older teenagers
and professional adults who previously endured
traditional orthodontia during adolescence, and
now require retreatment because of jaw growth
differences necessitating orthognathic surgery.
Less invasive orthodontic therapies, involving
clear aligners, are becoming increasingly popular, as they are less noticeable and less esthetically objectionable. They are typically indicated
for milder occlusal discrepancies, such as crowding and minor rotations, without signicant vertical or transverse problems.
Aligner orthodontics in combination with
orthognathic surgery for severe dentofacial problems is progressive, but additional auxiliaries are
needed. 8mm IMF screws at the mucogingival
line are used for intermaxillary xation. If the
maxilla is split in the middle or segmented, the
nal surgical splint, wired to the IMF screws,
remains 3–6weeks after the OGS.A new aligner
can then be used. Screws may be left in place, if
deemed necessary, for vertical pull or retraining
of the bite [39]. A recent study demonstrated signicantly better gingival health and patients’ satisfaction in those undergoing treatment with AO
relative to their counterparts with braces [39, 41].
Complications/Therapeutic Errors
Complications in orthognathic surgery commonly arise when preoperative planning and
communication between orthodontist and surgeon are insufcient. Outcomes that are unfavorable to both patient and practitioner can be
avoided when an overall consent for the treatment goal and planning was found by orthodontist, surgeon, and patient together [19].
The risk of complications is given with any
surgical intervention. Literature shows a great
variety of side effects after orthognathic surgery.
The most frequent complications are neurosen-
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sory disturbances, infections, relapse, condylar
resorption, and therefore TMJ problems as well
as damaged teeth and unsatisfactory occlusal outcome [42].
Any tooth movement that bears a potential for
relapse (e.g., expansion) should be avoided in
orthodontic presurgical treatment but rather be
performed in surgery in order to avoid dental
relapse [21].
Box Example
The female patient was 32years old when
she rst visited the orthodontic ofce. She
asked for advice considering the large sag-
ittal step and very prominent upper inci-
sors. After the short screening test was
performed and showed no signs for a tem-
poromandibular disorder, clinical inspec-
tion and orthodontic diagnostic records
were taken (Figs. 13.7, 13.8, 13.9, and
13.10).
Intraoral and extraoral photos show a
narrow upper arch with proclined incisors
and large buccal corridors. Tooth 26 was
missing, and tooth 27 started to migrate
into the space of 26. The dentist planned a
bridge for missing tooth 26 after orthodontics and OGS.The lower arch was also narrow with some rotations and extremely
proclined incisors. In habitual occlusion,
we found an asymmetrical Angle class II
occlusion of 1 premolar width on the right
and ½ premolar width on the left. A lower
midline shift to the right was identied.
Her face had a mild skeletal asymmetry.
Cephalometrics showed a skeletal class II
with a relative prognathism of the maxilla
and a relative retrognathism of the mandible. Conguration of cranial and jaw base
was vertical.
For the orthodontic pretreatment with
aligner orthodontics (AO), direct bonded
attachments (DBA) were bonded to upper
and lower canines and premolars before
intraoral scanning. Intraoral scanning was
W. Schupp et al.
performed, and the scan was implemented
into the OnyxCeph3™ software
(Fig.13.11). For the virtual treatment simulation, the following steps should be
applied:
1. Virtual alignment and leveling of the
arches: In order to create space and to
ll the buccal corridors, expansion of
the arch is indicated (Fig.13.12).
2. After expansion, all three dimensions of
the arches (transverse, sagittal, vertical)
are corrected virtually. Presurgical
decompensation is inevitable in combined orthodontic/orthognathic therapy.
In this case, decompensation was performed by reclination of lower incisors
and therefore enlarging the sagittal step
(Fig.13.13).
3. The extent of movements and potential
overlapping or spacing between teeth
need to be checked frequently and distributed equally if possible (Fig.13.14).
4. After virtual alignment, the shift and set
forward of the mandible are virtually
simulated (Fig. 13.15). It usually
impedes the necessity to detail the virtual treatment in order to obtain perfectly congruent bases (Fig.13.16).
Pretreatment was successfully performed with
35 stages of aligners. Diagnostic plaster models
were taken after orthodontic pretreatment. They
showed good congruence, so the patient was
referred to the orthognathic surgeon (U.Meyer,
Münster). He performed a surgical mandibular
shift and set forward and placed IMF screws
between rst and second premolars in the upper
and lower jaw for postsurgical retention purposes
(Figs.13.17 and 13.18).
Twenty-ve stages of additional aligners were
postsurgically produced in order to apply nishing to the orthodontic treatment. Hooks and buttons for class II elastics were bonded to upper
canines and lower rst molars in order to retain
a
c
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b
Fig. 13.7 (a–c) Initial extraoral records show relative retrognathism of the mandible, relative prognathism of the max-
illa, and buccal corridors
ab
de f
Fig. 13.8 (a–f) Initial intraoral records show narrow
arches, Angle class II occlusion on both left and right
sides, as well as moderate crowding and a dental midline
deviation in the lower arch. Direct bonded attachments
have been placed on teeth 13–15, 23–25, 27, 33–35, and
43–45
c
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W. Schupp et al.
the result of orthognathic surgery and to improve
class I interdigitation. Buttons for up and down
elastics were added to teeth 17, 16 and 46, 47.
Buttons for crisscross elastics were bonded to
teeth 27 and 37 (Fig.13.19).
At the end of the treatment, the patient showed
improved facial esthetics with a more harmonious
prole and relaxed lip closure. Midline shift was
corrected (Fig.13.20). Hooks and buttons for class
Fig. 13.9 Initial OPTG: Apical root resection on tooth 37
was performed prior to orthodontic consultation. Tooth 26
is missing, and tooth 27 is tilted. No caries or inammation visible
a
Fig. 13.10 (a and b) Initial lateral cephalometrics shows
relative prognathism of the maxilla, relative retrognathism
of the mandible, and skeletal class II relationship in the
sagittal dimension as well as a vertical growth pattern in
the vertical dimension. Incisors are protruded in both
arches
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b
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Fig. 13.10 (continued)
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Fig. 13.11 Initial scan matched into a virtual treatment software (V.T.O. 3D, OnyxCeph3™) with direct bonded attach-
ments on upper and lower canines and premolars and tooth 27
W. Schupp et al.
Fig. 13.12 First step of virtual treatment: Expansion of upper arch
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Fig. 13.13 Step 2 of virtual treatment: Alignment of upper and lower arches in all three dimensions: transverse, sagittal, and vertical
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Fig. 13.14 Protocols for spacing/overlapping of teeth and total amount of movement after virtual treatment
simulation
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