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Clinical Techniques and Technology
Distraction Osteogenesis Maxillary
Expansion (DOME) for Adult Obstructive
Sleep Apnea Patients with High Arched
Palate
Otolaryngology–
Head and Neck Surgery
2017, Vol. 157(2) 345–348
ÓAmerican Academy of
Otolaryngology—Head and Neck
Surgery Foundation 2017
Reprints and permission:
sagepub.com/journalsPermissions.nav
DOI: 10.1177/0194599817707168
http://otojournal.org
Stanley Yung-Chuan Liu, MD, DDS
1
,
Christian Guilleminault, MD, DBiol
2
, Leh-Kiong Huon, MD
3,4
,
and Audrey Yoon, DDS
5
No sponsorships or competing interests have been disclosed for this article.
Abstract
A narrow maxilla with high arched palate characterizes a phe-
notype of obstructive sleep apnea (OSA) patients that is asso-
ciated with increased nasal resistance and posterior tongue
displacement. Current maxillary expansion techniques for
adults are designed to correct dentofacial deformity. We
describe distraction osteogenesis maxillary expansion (DOME)
tailored to adult patients with OSA with narrow nasal floor
and high arched palate without soft tissue redundancy. DOME
is performed with placement of maxillary expanders secured
by mini-implants along the midpalatal suture. This minimizes
the maxillary osteotomies necessary to re-create sutural
separation for reliable expansion at the nasal floor and palatal
vault. We report the safety and efficacy profile of the first 20
patients at Stanford who underwent DOME.
Keywords
obstructive sleep apnea, nasal obstruction, high arched
palate, maxillary expansion, distraction osteogenesis, mini-
implant assisted rapid maxillary expander, bone-borne maxil-
lary expander, rapid palatal expander
Received October 26, 2016; revised March 21, 2017; accepted April 7,
2017.
Anarrow maxilla with high arched palate charac-
terizes a phenotype of patients with obstructive sleep
apnea (OSA).
1
This is associated with increased
nasal airflow resistance and posterior displacement of the
tongue.
2
Guilleminault et al
3
reported a 10.9-fold increase in
odds of OSA with this phenotype (Figure 1).
In pediatric OSA, maxillary expansion has been reported
with successful long-term results.
4
Systematic review also
reports that adults after maxillary expansion show improve-
ment in the apnea-hypopnea index (AHI) and subjective
daytime sleepiness.
2
Maxillary expansion can be performed noninvasively via
dental expanders prior to midpalatal suture fusion around
age 15 years. Until now, adult maxilla also has been
expanded with dental expanders in conjunction with surgery
to re-create maxillary sutures (Lefort osteotomy and midpa-
latal osteotomy).
This technical note addresses 2 shortcomings with cur-
rent techniques described for adult maxillary expansion, par-
ticularly in adults with OSA and narrow palate.
1. Current techniques are described for the correction
of dentofacial deformity. Most patients with OSA
have normal occlusion but may still present with
high arched palate and narrow nasal floor.
2. Dental expanders exert force at the maxillary
molars. This does not reliably expand the nasal
floor along the midpalatal region, which is perti-
nent for patients with OSA (Figure 2A,B).
We describe the safety and efficacy of distraction osteo-
genesis maxillary expansion (DOME) for 20 patients at
Stanford that addresses these shortcomings and where we
convert the palatal vault from an arched to domed
morphology.
1
Division of Sleep Surgery, Department of Otolaryngology–Head & Neck
Surgery, Stanford University School of Medicine, Stanford, California, USA
2
Stanford University Sleep Medicine Division, Stanford Outpatient Medical
Center, Redwood City, California, USA
3
Department of Otolaryngology–Head & Neck Surgery, Cathay General
Hospital, Taipei, Taiwan
4
School of Medicine, Fu Jen Catholic University, Taipei, Taiwan
5
Section of Pediatric Dentistry, Division of Growth and Development,
UCLA School of Dentistry, Los Angeles, California, USA
This article was presented at the 2016 AAO-HNSF Annual Meeting and
OTO EXPO; September 18-21, 2016; San Diego, California.
Corresponding Author:
Audrey Yoon, DDS, Section of Pediatric Dentistry, UCLA School of
Dentistry, 10833 Le Conte Ave, CHS 20-137, Los Angeles, CA 90095,
USA.
Email: jungdds@gmail.com
Materials and Methods
Subjects
From September 2014 to April 2016, a prospective cohort
study was conducted of 20 subjects (4 women and 16 men)
who underwent DOME after evaluation by Stanford Sleep
Medicine (C.G.) and Sleep Surgery (S.Y.-C.L., A.Y.).
Standard surgical consent was obtained for all subjects. This
study was approved by the Institutional Review Board of
Stanford University (protocol 36385, IRB 6208).
Subjects’ mean age was 31.7 66.5 years. Patients who
underwent DOME were uniformly (1) intolerant of continuous
positive airway pressure (CPAP) or oral appliance therapy, (2)
showed narrow palatal roof (measuring from 0.8-3 cm), (3)
had no palatine or lingual tonsillar hypertrophy, and (4) were
Mallampati class 4 (70%) or 3 (30%). All underwent pre- and
post-DOME polysomnography (PSG) at Stanford. Outcome
measures obtained include the Epworth Sleepiness Scale
(ESS), Nose Obstruction Symptom Evaluation (NOSE), rhino-
manometry, and computed tomography (CT) measurements of
the nasal floor (Table 1). Paired ttests were used for statistical
analysis with significance set at P\.05.
DOME—Description of Techniques
Step 1. Placement of maxillary expander with mini-implants
(orthodontist). The maxillary expander is custom-fabricated
to fit the narrow palatal vault. Four to 6 mini-implants are
placed along the midpalatal suture and into the maxillary
bone. The orthodontist places the implant and expander in
the office under local anesthesia.
Step 2. Maxillary osteotomy (surgeon). Two small incisions are
made 1 cm above the maxillary mucogingival junction bilat-
erally. Lefort level I osteotomies are made. A vertical inci-
sion is made between the maxillary incisor roots. A
piezoelectric saw is used to deepen the primordial groove of
the midpalatal suture. Thin straight osteotomes are used to
wedge open the midpalatal suture. A diastema (gap between
the maxillary incisors) is seen immediately as the suture
Figure 1. Adult patient with obstructive sleep apnea (OSA) with
maxillary morphology significant for a narrow nasal floor and high
arched palate.
Figure 2. The difference in expansion force with traditional maxillary expander vs mini-implant supported expander. (A,B) Traditional.
(C,D) Implant assisted. Red arrows show vector at nasal floor. Yellow line delineates maxillary anatomy.
346 Otolaryngology–Head and Neck Surgery 157(2)
opens (see Movie 1 in the online version of the article). The
expander is then turned to ensure symmetric and easy separa-
tion of the maxilla bilaterally, until a 1-mm diastema is seen
(see Movie 2 in the online version of the article).
Step 3. Expansion (patient). Patients turn the expander daily
(opens by 0.25 mm). Eight to 10 mm of expansion at the
nasal floor can be achieved within a month (Figure 3).
Step 4. Reestablish normal occlusion (orthodontist). Orthodontic
treatment to close the gap between maxillary incisors is ini-
tiated after completion of expansion (usually 1 month after
DOME surgery).
Results
Separation of the midpalatal suture and subsequent maxillary
and nasal floor expansion were successfully achieved in all
subjects. Significant reductions in ESS, NOSE, AHI, oxygen
desaturation index (ODI), and nasal airflow resistance were
seen. Increase of the nasal floor width at the levels of the naso-
palatine nerve and first molar palatal roots was also significant
(Table 1).
Sinus infection, oronasal fistula, loss of incisor teeth, and
malunion did not occur. Minor asymmetric maxillary expan-
sion occurred in 3 subjects but was within the range of
orthodontic correction. Resolution of V
2
paresthesia in the
Table 1. Demographic, Subjective, and Objective Parameters before and after Distraction Osteogenesis Maxillary Expansion (DOME)
Procedure.
a
Characteristic Before, Mean 6SD After, Mean 6SD Paired tTest, PValue
BMI 26.8 65.0 26.4 65.5 0.44
ESS 12.3 64.1 7.8 64.8 \0.001
NOSE 11.7 65.3 3.85 63.23 \0.001
AHI 30.9 627.1 14.2 69.3 \0.01
ODI 23.0 628.4 8.7 66.9 0.07
Reff Insp (left) 1.4 60.4 1.0 60.5 \0.001
Reff Insp (right) 1.4 60.4 0.9 60.3 \0.001
Nasal floor width—anterior, mm 22.7 64.58 27.4 64.7 \0.001
Nasal floor width—posterior, mm 27.9 64.3 32.1 64.8 \0.001
AHI, apnea-hypopnea index; BMI, body mass index; ESS, Epworth Sleepiness Scale; NOSE, Nose Obstruction Symptom Evaluation; ODI, oxygen desaturation
index; Reff Insp, effective resistance inspiration.
a
Anterior nasal floor width measured at the level of nasopalatine nerve; posterior nasal floor width measured at the level of maxillary first molar palatal root.
Figure 3. A 24-year-old woman with obstructive sleep apnea who underwent distraction osteogenesis maxillary expansion. (A-C) Nasal
floor width, palatal width, and occlusion at baseline. (D-F) One month after expansion. (G-I) Nine months after treatment (apnea-hypopnea
index from 12.2 to 3.8 events/h).
Liu et al 347
anterior maxilla ranged from 1 to 6 months. Three patients
exhibited transient decrease of perfusion to the maxillary
incisor with darker color change to the dentition. This
resolved over the course of orthodontic treatment. Class I
occlusion was achieved in all patients after expansion, with
no esthetic or functional compromise.
Discussion
We designed DOME to achieve maxillary expansion for
adult patients with OSA exhibiting high arched palate and
nasal obstruction. A similar phenotype in children has been
well addressed with maxillary expansion.
Existing adult maxillary expansion techniques, however, are
directed mainly for treating dentofacial deformity. Frequent
called SARPE (surgery-assisted rapid palatal expansion), it has
the shortcoming of using dental expanders that require invasive
osteotomy, including pterygoid plate fracture that carries signifi-
cant bleeding risk. Furthermore, forces exerted at the dentition
do not reliably lead to expansion of bone at the midpalatal junc-
tion, leading to a relapse rate as high as 64%.
5
With mini-implants, DOME negates the need to perform
pterygoid disjunction. Furthermore, the force is exerted at
the height of palatal vault and nasal floor. It is readily
applied to patients with normal, albeit narrow, jaw occlusal
relationship. Results need to be interpreted with the fact that
expanders remain in place for at least 8 months after dis-
traction osteogenesis, and we do not have data on long-term
relapse at this time.
Conclusion
DOME is conceived to widen the maxilla of adult patients
with OSA with high arched palate and normal occlusion. It
requires minimal maxillary osteotomies to reliably expand
the adult maxilla. The reduction in objective and subjective
measures of OSA in this patient phenotype requires long-
term follow-up to establish DOME as a form of ‘‘skeletal’’
palate surgery.
Author Contributions
Stanley Yung-Chuan Liu, original conception, design, analysis
and drafting the work, total clinical treatment and writing the
manuscript; Christian Guilleminault, data analysis, interpretation
of data, revising the work; Leh-Kiong Huon, acquisition of data
and revising the work; Audrey Yoon, original conception, design,
analysis and drafting the work, total clinical treatment and review-
ing the manuscript.
Disclosures
Competing interests: None.
Sponsorships: None.
Funding source: None.
Supplemental Material
Additional supporting information is available in the online version
of the article.
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348 Otolaryngology–Head and Neck Surgery 157(2)