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Recurrence of the Anterior Open Bite After Orthognathic Surgery: 3D Analysis of Dental, Soft Tissue, Skeletal and Airway Changes in Unravelling the Aetiology of Relapse

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Several treatment approaches have been used to correct anterior open bites, but high relapse rates are reported. This report shows the orthognathic surgical correction of a severe anterior open bite of a 23 years old woman with a mouth breathing habit. Although the treatment outcome was regarded as successful, progressive recurrence of the anterior open bite was found during 2 years retention. Digital dental models, 3D facial scans and CBCT were superimposed to analyse the dental, soft tissue, skeletal and airway volume changes during treatment and 2 years retention in three dimensions (3D). The Ortho Gnathic Analyser software tool was used to analyse in detail the skeletal dimensional changes (translations and rotations) of the maxilla and mandible in 3D. Relapse of the upper arch expansion was found in the posterior region. The impaction, advancement and clockwise pitch of the maxilla by the Le Fort 1 osteotomy were very unstable. The mandibular advancement and counter-clockwise pitch by the BSSO showed significant relapse. During retention a counter-clockwise roll of the maxilla was noticed, and considered as an adaptation to the relapse. The upper airway volume was reduced and the improvement of the soft tissue profile appeared to be unstable. 3D superimpositions made it possible to relate the oropharyngeal airway volume changes to the stability of the corrections of the dentition, maxilla and mandible and soft tissues. The orthognathic surgical treatment had reduced the upper airway volume, which maintained the mouth breathing habit, suggesting that this was the major cause of the dental, soft tissue and skeletal relapse. It is mandatory to collecting more 3D data on stability of hard and soft tissue and airway volume changes in unravelling the aetiology of relapse after orthognathic surgical correction of anterior open bites.
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Case Report
Suttorp et al., Oral health case Rep 2018, 4:2
DOI: 10.4172/2471-8726.1000148
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ISSN: 2471-8726
Oral Health Case Reports
Volume 4 • Issue 2 • 1000148
Oral health case Rep, an open access journal
ISSN: 2471-8726
*Corresponding author: Suttorp CM, Department of Orthodontics and
Craniofacial Biology, Radboud University Medical Centre, Nijmegen, The
Netherlands, Tel: +31-24-3614005, E-mail: Maarten.Suttorp@radboudumc.nl
Received: September 13, 2018; Accepted: November 20, 2018; Published:
November 22, 2018
Citation: Suttorp CM, Camardella LT, Desmedt DJS, Baan F, Maal TJJ, et al. (2018)
Recurrence of the Anterior Open Bite After Orthognathic Surgery: 3D Analysis of
Dental, Soft Tissue, Skeletal and Airway Changes in Unravelling the Aetiology of
Relapse. Oral Health Case Rep 4: 148. doi:10.4172/2471-8726.1000148
Copyright: © 2018 Suttorp CM, et al. This is an open-access article distributed
under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the
original author and source are credited.
Recurrence of the Anterior Open Bite After Orthognathic Surgery: 3D Analysis of
Dental, Soft Tissue, Skeletal and Airway Changes in Unravelling the Aetiology of
Relapse
Suttorp CM*, Camardella LT2, Desmedt DJS3, Baan F1, Maal TJJ1 and Breuning KH1
1Department of Orthodontics and Craniofacial Biology, Radboud University Medical Centre, Nijmegen, The Netherlands
2Department of Orthodontics, Federal Fluminense University Dental School, Brazil
3Department of Orthodontics, Private Practice in Diksmuide, Belgium
Keywords: 3-Dimensional evaluation; Orthodontics; Orthognathic
surgery; Relapse; Habit; Open bite
Introduction
An anterior open bite is diagnosed when there is a lack of vertical
overlap of the incisors compromising speech, swallowing and
mastication and facial aesthetics [1]. e aetiology of the anterior open
bite is multi-factorial as both hereditary and environmental factors
as: unfavourable growth patterns [1], enlarged lymphatic tissue [1],
oral habits and mouth breathing [2], are included. Several treatment
approaches have been performed to correct this malocclusion, but
high relapse rates are reported [3] (Figure 1). is report shows the
orthognathic surgical correction of a severe anterior open bite of a 23
years old woman with a mouth breathing habit. Although the treatment
outcome was regarded as successful, progressive recurrence of the
anterior open bite was found during 2 years retention. e mouth
breathing habit had not been corrected into nose breathing at rest. e
improvement of the so tissue prole showed signicant relapse during
retention, and a counter-clockwise cant of the occlusal plane was noticed.
In literature, relapse aer orthognathic surgery is mainly measured on
cephalograms, only containing data from the anatomy in the sagittal
plane (translations and pitch rotation). A disadvantage is that no data
are available from relapse in the frontal plane (translations and roll
rotation) and the transverse plane, (translations and yaw rotation), and
changes in the airway volume. To better understand the relapse it was
decided to collect detailed information about the 3 dimensional (3D)
changes of the hard and so tissues and oropharyngeal airway volume.
Digital dental models, 3D facial scans and CBCT were superimposed
to analyse the dental, so tissue, skeletal and airway volume changes
during treatment and retention. By using the semi-automated Ortho
Gnathic Analyser soware tool [4,5], detailed information of the
Abstract
Several treatment approaches have been used to correct anterior open bites, but high relapse rates are reported.
This report shows the orthognathic surgical correction of a severe anterior open bite of a 23 years old woman with a mouth
breathing habit. Although the treatment outcome was regarded as successful, progressive recurrence of the anterior
open bite was found during 2 years retention. Digital dental models, 3D facial scans and CBCT were superimposed
to analyse the dental, soft tissue, skeletal and airway volume changes during treatment and 2 years retention in three
dimensions (3D). The Ortho Gnathic Analyser software tool was used to analyse in detail the skeletal dimensional
changes (translations and rotations) of the maxilla and mandible in 3D. Relapse of the upper arch expansion was found
in the posterior region. The impaction, advancement and clockwise pitch of the maxilla by the Le Fort 1 osteotomy were
very unstable. The mandibular advancement and counter-clockwise pitch by the BSSO showed significant relapse.
During retention a counter-clockwise roll of the maxilla was noticed, and considered as an adaptation to the relapse.
The upper airway volume was reduced and the improvement of the soft tissue profile appeared to be unstable. 3D
superimpositions made it possible to relate the oropharyngeal airway volume changes to the stability of the corrections
of the dentition, maxilla and mandible and soft tissues. The orthognathic surgical treatment had reduced the upper
airway volume, which maintained the mouth breathing habit, suggesting that this was the major cause of the dental, soft
tissue and skeletal relapse. It is mandatory to collecting more 3D data on stability of hard and soft tissue and airway
volume changes in unravelling the aetiology of relapse after orthognathic surgical correction of anterior open bites.
dimensional changes (translations, and pitch, roll and yaw rotations)
of the maxilla and mandible in 3D were obtained. e methods used to
perform the 3-D superimpositions will be described in this article. e
purpose of this case report is to illustrate the advantage of 3-D analysis
of hard and so tissues and airway volumes in unravelling the aetiology
of relapse aer orthognathic surgical correction of anterior open bites.
Aetiology and Diagnosis
During childhood (between 12 and 14 years of age) the patient was
treated at our department with full xed appliances. Class II elastic
traction was used to correct the discrepancy in the interact relationship,
but elastic traction did not completely correct the anterior open
bite (Table 1). Due to poor compliance and bad oral hygiene it was
decided to nish the treatment prematurely, and the poor result was
accepted by the patient. e written status, copies of extra and intraoral
photographs (Figure 2) and the dental plaster models made at the start
and nish of this orthodontic treatment were available. Nine years
aer the end of the orthodontic treatment, at the age of 23 years, the
patient returned to the orthodontic department because of functional
Page 2 of 11
Volume 4 • Issue 2 • 1000148
Oral health case Rep, an open access journal
ISSN: 2471-8726
Citation: Suttorp CM, Camardella LT, Desmedt DJS, Baan F, Maal TJJ, et al. (2018) Recurrence of the Anterior Open Bite After Orthognathic Surgery:
3D Analysis of Dental, Soft Tissue, Skeletal and Airway Changes in Unravelling the Aetiology of Relapse. Oral health case Rep 4: 148.
doi:10.4172/2471-8726.1000148
Figure 1: (A) Example of a high angle case with mandibular retrusion and anterior open bite treated at our department demonstrating relapse of the
orthognathic surgical correction of a severe anterior open bite. (B) Extra and intraoral photographs before orthognathic surgical treatment after
orthognathic surgical treatment (C) and 2 years after orthognathic surgical treatment.
complaints, such as diculties with mastication due to the severe open
bite and incompetent lip closure. She also mentioned some aesthetic
complaints: an open mouth posture and in her opinion a “long face”.
During clinical evaluation the patient demonstrated an open mouth
posture with a mouth breathing habit at rest, although there was no
evident nose obstruction detected. A traditional set of photographs
(Figure 3A), impressions, and a cone beam computed tomography
(CBCT) scan and a 3D facial scan were made. e Class II jaw relation
and Class II malocclusion corresponded with the tapered dental arch
form in the maxilla. It can be speculated that a combination of the
open mouth posture together with the mouth breathing habit resulted
in an excessive vertical growth of the maxilla, Class II jaw relation, low
tongue position, a narrow maxillary dental arch, a reversed curve of
Spee in the mandibular dental arch and a severe anterior open bite.
Treatment objectives and alternative treatment plans
Treatment objectives for this patient were: closure of the severe
anterior open bite and reduction of the overjet, modication of the
tapered arch form in the maxilla, correction of the Class II cuspid
occlusion, correction of the midline shi of the upper arch, correction
of the reversed curve of Spee in the lower arch, achievement of a
competent lip closure, reduction of the anterior lower face height,
increase of the chin prominence, improvement of the prole and
smile aesthetics, and correction of the mouth breathing habit into
nose breathing at rest. In this case the anterior open bite could might
have been closed by intrusion of the posterior teeth of the maxilla and
mandible. It has been reported that eective orthodontic intrusion of
the upper molars in adult patients can be obtained by using posterior
bite-blocks [6], temporary anchorage devices such as zygoma anchors
[7], palatal implants [8] or other temporary anchorage devices [9].
A disadvantage of this treatment option is that the narrow maxillary
arch will not be corrected, and her long face and Class II prole will
only slightly improve. Alternatively, the anterior open bite could have
been corrected by a surgical approach [10]. By performing a maxillary
anterior segmental osteotomy the anterior open bite could have been
closed by downward rotation of the anterior segment [11]. Otherwise,
this surgical approach would not improve the increased lower anterior
face height and would not correct the lip incompetence. Because of
the relapse of the anterior open bite and her aesthetic and functional
complaints, an orthognathic surgical treatment plan was proposed. A
Page 3 of 11
Citation: Suttorp CM, Camardella LT, Desmedt DJS, Baan F, Maal TJJ, et al. (2018) Recurrence of the Anterior Open Bite After Orthognathic Surgery:
3D Analysis of Dental, Soft Tissue, Skeletal and Airway Changes in Unravelling the Aetiology of Relapse. Oral health case Rep 4: 148.
doi:10.4172/2471-8726.1000148
Volume 4 • Issue 1 • 1000143
Oral health case Rep, an open access journal
ISSN: 2471-8726
Figure 3: (A) Extra and intraoral photographs before orthognathic surgical treatment (B), and 9 weeks before BIMAX surgery.
Figure 2: (A) Extra and intraoral photographs before (B) and after orthodontic treatment.
Page 4 of 11
Volume 4 • Issue 2 • 1000148
Oral health case Rep, an open access journal
ISSN: 2471-8726
Citation: Suttorp CM, Camardella LT, Desmedt DJS, Baan F, Maal TJJ, et al. (2018) Recurrence of the Anterior Open Bite After Orthognathic Surgery:
3D Analysis of Dental, Soft Tissue, Skeletal and Airway Changes in Unravelling the Aetiology of Relapse. Oral health case Rep 4: 148.
doi:10.4172/2471-8726.1000148
Surgically Assisted Rapid Maxillary Expansion (SARME) procedure
was planned to widen the maxilla and to improve the dimensions of
the nose cavity. Extraction of the second premolars in the mandible
was indicated, creating space to correct the reversed curve of Spee
and to increase the overjet, necessary for surgical advancement of the
mandible. Aer removal of the Hyrax expander a transpalatal arch
(TPA) would be placed in the maxillary arch to retain the expansion.
Full xed appliances in the maxillary and mandibular arch would
be used to align the dentition, to close the extraction diastemas and
correct the reversed curve of Spee. When both arches are corrected the
0.016” × 0.022” stainless steel wire should be cut between the cuspids
and rst premolars to evaluate the stability of the dental correction
in the incisor region. In case of recurrence of the anterior open bite,
an additional maxillary anterior segmental osteotomy should be
performed to close the open bite. e long face and the anterior open
bite would be corrected by a Le Fort I osteotomy impaction of the
maxilla together with a clockwise pitch rotation. e overjet would be
corrected by the Bilateral Sagittal Split Osteotomy (BSSO). Finally, a
chin advancement osteotomy would be performed to improve the chin
prominence. During the pre and post-surgical orthodontic treatment,
the patient would be referred to a speech therapist to correct the open
mouth posture and mouth breathing habit. Fixed retainers behind the
maxillary and mandibular incisors and cuspids (C-C bars) should be
placed to retain the tooth position aer treatment. A removable clear
retainer would be used at night to retain the maxillary arch width.
Treatment progress
A conventional Hyrax with bands on both rst premolars and
molars was placed one week before the SARME. e SARME procedure
was performed under general anaesthesia as previously described
[12]. e extractions of the second premolars in the mandible were
performed directly aer the SARME. Five days aer SARME the
patient was instructed to activate the device twice a day for 16 days,
generating a daily expansion of 0,5 mm. e Hyrax expander was
removed 4 months aer SARME, and the TPA was placed between the
upper rst molars to retain the expansion. Pre-adjusted self-ligating
brackets (0.018 × 0.025-in slot) with interactive clip (In-Ovation R,
Dentsply Sirona, York, USA) were placed in the upper- and lower arch.
Extraction diastemas were closed with elastic chains. Eventually, both
wires (0.016” × 0.022” stainless steel) were cut between the cuspids
and rst premolars and the dental correction in the incisor region
appeared to be stable during 10 weeks follow-up (Table 1 and Figure
3B). Aer 8 months in situ, and 4 weeks prior to BIMAX, the TPA was
removed because of the interference with CBCT imaging. A 3D digital
pre-surgical set-up was performed using Maxilim® soware (Medicim
Figure 4: (A) Extra and intraoral photographs after orthognathic surgical treatment (B), and 2 years after orthognathic surgical treatment.
Page 5 of 11
Volume 4 • Issue 2 • 1000148
Oral health case Rep, an open access journal
ISSN: 2471-8726
Citation: Suttorp CM, Camardella LT, Desmedt DJS, Baan F, Maal TJJ, et al. (2018) Recurrence of the Anterior Open Bite After Orthognathic Surgery:
3D Analysis of Dental, Soft Tissue, Skeletal and Airway Changes in Unravelling the Aetiology of Relapse. Oral health case Rep 4: 148.
doi:10.4172/2471-8726.1000148
NV, Mechelen, Belgium) whereof the occlusal wafers were designed
and 3D printed. e bi-maxillary surgical procedure (BIMAX); the Le
Fort I osteotomy, Bilateral Sagittal Split osteotomy (BSSO) and chin
osteotomy procedures were carried out under general anaesthesia,
as described elsewhere [4]. e BSSO was performed according to
Obwegeser-Dal Pont technique including the Hunsuck modication.
e maxilla and the mandibular anterior segment were both positioned
using the 3D printed acrylic occlusal wafers according to the virtual
surgical planning. e bone segments were xed with osteosynthesis
plates. Two weeks aer BIMAX surgery the patient was instructed to
wear Class II elastics (¼ in, 3.5 oz). Despite the use of elastic traction
relapse of the open bite correction occurred. At the control visit seven
weeks aer the BIMAX, the reopening of the anterior overbite was still
present. It was decided to replace the sectioned wires by continuous
stainless steel wires (0.016” × 0.022”) in the upper arch to close the
anterior open bite. Aer two months of elastic traction, the vertical
position of the incisors was corrected, but relapse of the Class II
occlusion had occurred. Inter-arch Class II correction springs (Forsus™
Fatigue Resistant Device, 3M Unitek, USA) were placed to correct the
persisting Class II occlusion, and within 10 weeks a Class I cuspid and
Class III molar occlusion was achieved. It was then decided to promptly
nish the orthodontic treatment.
Figure 5: Dental changes visualized with superimpositions of digital dental models in 3D.
Page 6 of 11
Volume 4 • Issue 2 • 1000148
Oral health case Rep, an open access journal
ISSN: 2471-8726
Citation: Suttorp CM, Camardella LT, Desmedt DJS, Baan F, Maal TJJ, et al. (2018) Recurrence of the Anterior Open Bite After Orthognathic Surgery:
3D Analysis of Dental, Soft Tissue, Skeletal and Airway Changes in Unravelling the Aetiology of Relapse. Oral health case Rep 4: 148.
doi:10.4172/2471-8726.1000148
Treatment results
e C-C bars were placed and extra and intraoral photographs and
dental impressions were taken direct aer debonding (Figure 4A). e
photographs “en face”, at rest and during smiling show balanced facial
dimensions, but an asymmetrical smile. e treatment outcome was
regarded as very successful by both the practitioner and the patient.
For retention of the upper arch width the patient was instructed to
wear a removable clear retainer at night. Total treatment time for the
orthognathic surgical treatment was 2 years and 1 month.
Case retention
Aer 6 weeks retention the occlusion appeared to be stable.
However, 1 year aer treatment an overjet of 4 mm was observed
without vertical contact of the incisors. e patient was instructed to
gradually reduce wearing the removable clear retainer. At the 2 years
retention visit signicant relapse of the anterior open bite was found,
and a counter-clockwise cant of the occlusal plane was noticed (Figure
4B and Table 1).
Method of Relapse Analysis using 3-D
Superimpositions
Obtaining more insight in the relapse of the anterior open bite
correction we decided to quantify the dimensional changes of the
dierent facial structures. erefore, 3D digital dental models, 3D
facial scans and CBCT scans collected during orthognathic treatment
and 2 years retention were superimposed to analyse the changes of the
hard and so tissues of the face and the oropharyngeal airway volume
in 3D. e dental plaster models (orthodontic treatment between 12
and 14 years of age) and the dental impressions (orthognathic surgical
treatment and 2 years retention) were digitized with a CT scanner by
the Orthoproof company (Nieuwegein, the Netherlands). e digital
dental models were constructed from stereolitographic les (STL les)
with Ortho Analyzer soware (3-Shape, Copenhagen, Denmark).
Superimpositions were performed with Geomagic Qualify soware
(3D Systems, Rock Hill, South Carolina, USA). For superimposition
of the upper arch the volume around the palatal rugae was used as a
stable reference structure [13]. Superimpositioning of the lower arch
was less reliable due to the lack of accurate bony reference structures
[14]. By default, the models of the lower arch were superimposed on
the two second molars, because both were not bonded during this
treatment (Figure 5). Facial so tissue surface changes were visualized
with superimpositions of 3D facial scans (Figure 6). A 3D stereo
photogrammetric camera set-up (3dMD face™ System, 3dMD LLC,
Atlanta, GA, USA) was used to make facial scans of the head. e facial
scans were imported into Maxilim® soware and resized to the region of
Figure 6: Facial soft tissue surface changes visualized with superimpositions of 3D facial scans.
Page 7 of 11
Volume 4 • Issue 2 • 1000148
Oral health case Rep, an open access journal
ISSN: 2471-8726
Citation: Suttorp CM, Camardella LT, Desmedt DJS, Baan F, Maal TJJ, et al. (2018) Recurrence of the Anterior Open Bite After Orthognathic Surgery:
3D Analysis of Dental, Soft Tissue, Skeletal and Airway Changes in Unravelling the Aetiology of Relapse. Oral health case Rep 4: 148.
doi:10.4172/2471-8726.1000148
interest. A surface based matching procedure was performed by placing
landmarks on the surface of the facial scans, as described elsewhere
[15]. Virtual 3D models of the CBCT of the skull were reconstructed
and the superimpositions were made with “Maxilim®” soware, version
2.2.2.1 (Medicim NV, Mechelen, Belgium). e superimpositions of the
3D skull models were performed using voxel-based registration upon
the anterior cranial base [16] (Figure 7). By using the semi-automated
OrthoGnathicAnalyser soware tool [4,5], detailed information
about individual changes in the sagittal plane (translations and
pitch rotation), frontal plane (translations and roll rotation) and the
transverse plane (translations and yaw rotation), of the maxillary and
mandibular segments were obtained by performing superimpositions
in multiple steps (Figure 8), as described elsewhere [4]. Cephalometric
landmarks were placed at the preoperative maxillary and mandibular
bone segments and virtual triangles were constructed which contained
information on the preoperative 3D position and orientation (Figure
8A). Pre and postoperative maxillary and mandibular segments were
superimposed using the cranial base as a stable reference (Figure
8B). e virtual triangle of each segment was translated from the 3D
preoperative position to the postoperative position (Figure 8C). e
coordinates of the triangles were imported into OrthoGnathicAnalyser
and information about the translations (anterior/posterior, le/right
and up/down) as well as the rotations (pitch, roll and yaw) were
obtained (Figure 8D). e changes of the individual maxillary and
mandibular segments as the result of the BIMAX surgery (T0) and 2
years retention (T1) were compared, and the dierence between T1
and T0 was calculated. Pharyngeal airway volumes before orthognathic
surgical treatment and aer 2 years retention were obtained from
CBCT data and were visualized and superimposed in 3D. Virtual 3D
models of the airway was reconstructed from the CBCT with “Maxilim®
soware. Superimposition of the airways with the same soware was
performed using voxel-based registration upon the anterior cranial
base (Figure 9).
3-D Analysis Results
e superimposed digital dental models demonstrated signicant
relapse of the upper dental arch expansion in the posterior region
(premolars and molars) aer both the orthodontic treatment and
orthognathic surgical treatment (Figure 5). Superimpositions of
the facial scans demonstrated an increase of the anterior lower face
height, a reduction of the prominence of the chin, the upper- and
lower lip and the cheek region during 2 years retention (Figure 6).
e superimposed 3D skull models demonstrated increase of the
anterior lower face height, caudal displacement of the maxillary
segment, dorsal displacement of the maxilla and anterior segment of
the mandible, and recurrence of the anterior open bite (Figure 7). e
OrthoGnathicAnalyser soware measured dimensional changes in
Figure 7: Skeletal changes visualized with superimpositions of the skull in 3D from CBCT images.
Page 8 of 11
Volume 4 • Issue 2 • 1000148
Oral health case Rep, an open access journal
ISSN: 2471-8726
Citation: Suttorp CM, Camardella LT, Desmedt DJS, Baan F, Maal TJJ, et al. (2018) Recurrence of the Anterior Open Bite After Orthognathic Surgery:
3D Analysis of Dental, Soft Tissue, Skeletal and Airway Changes in Unravelling the Aetiology of Relapse. Oral health case Rep 4: 148.
doi:10.4172/2471-8726.1000148
the opposite direction of the orthognathic surgical correction, which
were considered as relapse (dierence and percentage displayed in red
colour). On the other hand, dimensional changes in the same direction
of the orthognathic surgical correction were also found (dierence
and percentage in green) considered as an adaptation to the relapse
(Figure 8D). For the maxilla high relapse rates of the clockwise pitch
rotation (90.5%), impaction (44.4%) and advancement (54.4%) were
measured. In the frontal plane counter-clockwise roll (63.4%), and
in the transverse plane translation (1.88 mm) and yaw (12.1%) were
found to be an adaptation. For the mandibular anterior segment
relapse of the clockwise pitch (42.1%), and advancement (25.7%) were
measured. In the frontal plane the counter-clockwise roll (15.3%), and
Figure 8: The illustrations explained the method of superimposing of individual maxillary and mandibular bone segments to quantify the dimensional changes in
3D by the BIMAX surgery (T0) and during 2 years retention (T1).
Stage Age Angle occlusion Molar occlusion right Molar occlusion left Overjet Overbite Midline shift
Before orthodonic treatment 12 Class II/1 1/4 cusp disto 5/4 cusp disto 6 mm -3 mm Maxilla 3 mm to the
right
After orthodonic treatment 14 Class II/1 1/4 cusp disto 5/4 cusp disto 7 mm -4 mm Maxilla 3 mm to the
right
Before Orthognatic surgical
treatment 23 Class II/1 1/4 cusp disto 5/4 cusp disto 6 mm -5 mm Maxilla 3 mm to the
right
Before BIMAX Surgery 24 Class III subdivision right 1/4 cusp disto neutro 13 mm 0 mm Maxilla 2 mm to the
right
After Orthognatic surgical
treatment 25 Class III 1 cusp mesio 1 cusp mesio 2 mm 2 mm Straight
2 Years retention 27 Class II/1 1/2 cusp disto 1/2 cusp disto 5 mm -2 mm Straight
Table 1: Dental characteristics per stage.
Page 9 of 11
Volume 4 • Issue 2 • 1000148
Oral health case Rep, an open access journal
ISSN: 2471-8726
Citation: Suttorp CM, Camardella LT, Desmedt DJS, Baan F, Maal TJJ, et al. (2018) Recurrence of the Anterior Open Bite After Orthognathic Surgery:
3D Analysis of Dental, Soft Tissue, Skeletal and Airway Changes in Unravelling the Aetiology of Relapse. Oral health case Rep 4: 148.
doi:10.4172/2471-8726.1000148
in the transverse plane the translation (1.02 mm) and yaw (9.1%) were
found to be an adaptation. Although the maxilla was expanded by the
SARME the upper airway volume was found to be decreased due to
the cranial displacement of the oor of the maxillary sinus by the Le
Fort 1 osteotomy, even aer 2 years retention. e lower pharyngeal
airway volume was signicantly increased by the orthognathic surgical
treatment, and this was stable during 2 years retention (Figure 9).
Discussion
Several treatment approaches are able to correct severe anterior
open bites, but high relapse rates are reported during retention [3].
Real success of anterior open bite corrections should thus be measured
by its long term stability [17], as demonstrated by this case report.
Besides the recurrence of the open bite the orthognathic treatment
was also not successful in correcting the mouth breathing habit. For
mouth breathers dierent cephalometric parameters were found, such
as mandibular retrusion and posterior rotation, increased anterior face
height, anterior open bite and increased maxillary and mandibular
dentoalveolar height [18,19]. Notably, all these parameters were present
in our case. e oropharyngeal airway appear to smaller subjects with a
vertical growth pattern [20] and mandibular retrusion [21]. Moreover,
on cephalograms, anteroposterior narrowing of the upper airways,
mainly in the nasopharynx and oropharynx, was observed in anterior
open bite cases [19]. erefore, development of more understanding
about the relation between the stability of the anterior open bite
correction and airway function is mandatory. We need to discuss the
individual steps of the orthognathic surgery performed in our case
in relation to its inuence on the airway volume and the stability of
the dental, so tissue and skeletal changes in the long term. Despite
the overexpansion of the upper dental arch aer SARME performed
in our case, as recommended in literature [22], we found signicant
relapse in the posterior region aer 2 years retention. It has previously
been demonstrated that both orthodontic palatal expansion and
SARME showed up to 30% decrease in transverse molar width aer
3 years follow-up [22]. Orthodontic rapid palatal expansion is mainly
performed in patients in the range from 7 to 15 years of age [23]. Even
the use of a TPA aer SARME does not improve stability in the long
term [24]. However, in Class II patients with transverse discrepancies
60% relapse found of the surgical expansion by a 2-piece maxillary
osteotomy [25]. Apparently, upper arch expansion by both orthodontics
and surgery are prone to relapse in the long term. We presume that
the relapse of the upper dental arch expansion aected the occlusion
and contributed to the recurrence of the anterior open bite in our case.
In literature, relapse was found to occur aer both surgical and non-
surgical closure of anterior open bites [3,26,27]. Vertical impaction
of the maxilla by the Le Fort 1 osteotomy usually provides a stable
result in cases with a maxillary facial height excess [28,29]. Otherwise,
in anterior open bite cases reopening of the anterior bite aer the Le
Fort 1 osteotomy was found during long-term follow-up [10]. Long-
term skeletal relapse seems even to be more common aer bi-maxillary
surgery, since relapse of 2-4 mm of the open bite in 7% of the Le Fort
1 osteotomy group and 12% in the BIMAX group was observed [30].
It is known that large surgical advancements (more than 6 to 7 mm)
of the mandible are more prone to relapse, explained by the increased
so tissue and muscular tension [31,32]. It was found that especially
in high angle cases more horizontal relapse occurred aer mandibular
lengthening, possibly as a result of the increased muscular tension to
Figure 9: Airway volume changes visualized with superimpositions of CBCT images in 3D.
Page 10 of 11
Volume 4 • Issue 2 • 1000148
Oral health case Rep, an open access journal
ISSN: 2471-8726
Citation: Suttorp CM, Camardella LT, Desmedt DJS, Baan F, Maal TJJ, et al. (2018) Recurrence of the Anterior Open Bite After Orthognathic Surgery:
3D Analysis of Dental, Soft Tissue, Skeletal and Airway Changes in Unravelling the Aetiology of Relapse. Oral health case Rep 4: 148.
doi:10.4172/2471-8726.1000148
the proximal segment to the original inclination [33,34]. Relapse of the
counter clockwise pitch rotation of the maxilla-mandibular complex
was also found aer bi-maxillary surgery [35]. e authors note that
alternative orthognathic surgical treatments exists, such as a 3- piece
maxillary osteotomy including an additional maxillary anterior
segmental osteotomy. According to the literature, it can be supposed
that in general vertical impaction of the maxilla and advancement of
the mandible are both basically regarded as surgical corrections with
a stable outcome, but especially in anterior open bite cases relapse can
be expected. Our 3D superimposition of the airway demonstrated that
lengthening of the mandible by the BSSO procedure increased the lower
pharyngeal airway volume, which was also found by others [36]. On the
contrary, the cranial impaction of the oor of the maxillary sinus, as a
result of the Le Fort 1 osteotomy, reduced the vertical dimension of the
upper airway. Aer treatment the mouth breathing was still present
despite the speech therapy, erefore, it is tempting to speculate that
the upper airway volume reduction maintained at least the mouth
breathing habit at rest, probably the major cause of relapse. Detailed
information was obtained by analysis of the dimensional changes of the
maxillary and mandibular segments using the OrthoGnathicAnalyser
soware tool [4,5] (Figure 8D). All dimensional changes in the opposite
direction of the orthognathic surgical correction were considered
as relapse according to its denition [37] the recurrence of the open
bite was found to occur as the result of the counter-clockwise pitch
and dorsal and caudal translation of the maxilla in the sagittal plane
during 2 years retention. e counter-clockwise pitch and dorsal
translation of the mandible also contributed to the relapse of the open
bite correction. In addition, dimensional changes in the same direction
of the orthognathic surgical correction were also found, regarded
as adaptations to the relapse. In the frontal plane the maxilla and
mandible demonstrated counter-clockwise roll, and in the transverse
plane translation and yaw was found. However, dimensional changes
of the maxilla and mandible as the result of relapse and adaptation
aected the occlusion and stability of the anterior open bite correction.
In conclusion, 3D analysis made it possible to compare oropharyngeal
airway changes to the dental, so tissue and skeletal changes. e
changes of the dentition, maxilla and mandible occurred in three
dimensions and contributed to the recurrence of the anterior open bite.
It should be realized that in most studies on relapse aer orthognathic
surgical anterior open bite corrections data are mainly obtained from
cephalograms, only containing information from the anatomy in the
sagittal plane. No data from the anatomical changes in the frontal
and transverse plane are then available. Besides, it is not possible to
measure the 3D upper airway volume changes on cephalograms. In
high angle cases, and especially in anterior open bite cases small airway
volumes were found, indicating that vertical impaction of the maxilla
is absolutely unfavourable. Recently, a study was performed on the
stability of surgical anterior open bite corrections using 3D designed
drilling guides and pre-bent titanium plates. Successful closure of the
anterior open bites was demonstrated but relapse was just measured
18 months aer treatment and no measurements were performed
on the oropharyngeal airway changes [38]. In search for more stable
treatment outcome it might be reasonable to plan the orthognathic
surgery from the upper airway ventilation perspective instead of
aesthetics only. More knowledge on relapse might have implications on
future diagnosis, treatment planning, treatment outcome and retention
protocols for anterior open bite cases.
Conclusion
is report showed the recurrence of the anterior open bite aer
orthognathic surgery. Digital dental models, 3D facial scans and
CBCT were superimposed to analyse the dental, so tissue, skeletal
and airway volume changes during treatment and retention in three
dimensions (3D). e upper airway volume was found to be reduced
by the orthognathic surgery, and the mouth breathing habit was not
corrected. e 3D superimpositions showed that the combination
of dimensional changes of the dentition, maxilla and mandible
contributed to the recurrence of the anterior open bite. It is tempting
to speculate that the upper airway volume reduction as the result of
the orthognathic surgery aected the patient’s airway ventilation, the
major cause of relapse. Collecting more 3D data on stability of hard and
so tissues and airway volumes aer orthognathic surgery is essential
in unravelling the aetiology of relapse.
Declarations
Ethics approval and consent to participate
is case report was approved by the Committee on Human
Research (CMO) of the Radboudumc, Nijmegen, Netherlands.
Consent for publication
Written informed consent was obtained from the patient for
publication of this report and accompanying images.
Availability of data and supporting materials
e materials and results obtained in this study belong to the
authors and are therefore available only upon request, aer approval
by the author.
Funding
e authors declare that no funding was given for the realization
of this report
Acknowledgements
Not applicable.
Competing Interests
The authors declare that they have no competing interests.
Author’s Contributions
CS: Performed the follow-up, analyzed and interpreted data, performed the
superimpositions of the CBCT and drafted the manuscript. LC: Performed the
superimpositions of the dental models. DD performed the orthodontic treatment
and created the superimpositions of the facial scans. FB: Performed the
superimpositions of the CBCT scans and designed the Ortho Gnathic Analyser
software. TM: designed the Ortho Gnathic Analyser software. KB: Revised the
manuscript. All authors read and approved the final manuscript
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