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ORTHODONTICS
STABILITY OF SKELETAL CLASS III MALOCCLUSION
Review Articles
AFTER ORTHOGNATHIC SURGERY AND ORTHODONTIC
TREATMENT: A SYSTEMATIC REVIEW AND
META-ANALYSIS
Abdolreza Jamilian1a* , Ludovica Nucci2b , Ali Fateh1c , Mitra Toliat1d , Alireza Darnahal3e , Madi Alassadi3f ,
Chin Wei Wang3g
1
Department of Orthodontics, Cranio-Maxillofacial Research Center, Tehran University of Medical Sciences, Islamic Azad University, Tehran, Iran
2
Multidisciplinary Department of Medical-Surgical and Dental Specialties, Dental School, University of Campania Luigi Vanvitelli, Naples, Italy
3
Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, MI 48109, USA
a
DDS, MSc, OMFS, Professor; e-mail: info@jamilian.net; ORCIDiD: https://orcid.org/0000-0002-8841-0447
b
Undergraduate Dental Student; e-mail: ludovica.nucci@virgilio.it; ORCIDiD: https://orcid.org/0000-0002-7174-7596
c
DDS, Executive Manager; e-mail: Af_fateh@yahoo.com; ORCIDiD: https://orcid.org/0000-0002-1895-0632
d
DDS; e-mail: Toliatmitra@gmail.com
e
Post Doctorate Student; e-mail: alirezadarnahal@gmail.com; ORCIDiD: https://orcid.org/0000-0001-9629-731X
f
Post Doctorate Student; e-mail: alassadi@umich.edu
g
DDS, Clinical Assistant Professor, Director of Predoctoral Periodontics; e-mail: Jeffwa@umich.edu; ORCIDiD: https://orcid.org/0000-0003-2274-8901
ABSTRACT https://doi.org/10.25241/stomaeduj.2020.7(1).art.7
Background Relapse is one of the major concerns in the correction of skeletal class III malocclusion.
Objective The purpose of this systemic review was to evaluate the degree of relapse on skeletal class III
patients who received bimaxillary surgery or mandibular setback with orthodontic treatment.
Data Sources A search of the literature was performed in the databases of PubMed, Google Scholar Beta,
Scopus, Web of Science, and the Cochrane Library.
Study Selection Out of the 165 articles identified, 73 studies were obtained, once duplicated articles were
excluded. Then, 40 other records were excluded due to titles and abstracts, and 20 were removed for not
fulfilling exclusion/inclusion criteria. 11 studies met the final inclusion criteria. Some cephalometric data
during T1–T2–T3 were measured.
Data Extraction SNA did not have any significant changes within less than 2 years but it increased
significantly after 2 years. SNB did not have any significant changes in more than 2 years’ follow-up, while it
rose significantly in less than 2 years. Overjet decreased significantly after 2 years but not earlier than this
duration. Overbite intensified significantly in more than 2 years and not earlier.
Data Synthesis SNA and overbite increased significantly after 2 years. SNB increased significantly before 2
years and did not have any changes after it. Overjet was significantly reduced after 2 years.
KEYWORDS
Class III; Skeletal and Dental Changes; Stability; Bimaxillary Surgery or Mandibular Setback; Systematic
Review and Meta-Analysis.
1. INTRODUCTION surgery and orthodontic treatment [1-4]. However,
bimaxillary surgery has gradually become more
Moderate to severe skeletal class III patients often popular to correct class III malocclusion [5-7].
require a combined orthodontic and surgical It has been estimated that 20% to 25% of all Class III
approach for treatment. It has been reported that cases have true mandibular prognathism suggesting
skeletal class III malocclusion is the most frequent that at least 75% of all class III malocclusions have
deformity corrected by combined orthognathic some degree of maxillary retrusion. Given this
OPEN ACCESS This is an Open Access article under the CC BY-NC 4.0 license.
Peer-Reviewed Article
Citation: Jamilian A, Nucci L, Fateh A, Toliat M, Darnahal A, Alassadi M, Wang CW. Stability of skeletal Class III malocclusion after orthognathic surgery and
orthodontic treatment: a systematic review and meta-analysis. Stoma Edu J. 2020;7(1):52-67.
Received: February 06, 2020; Revised: February 13, 2020; Accepted: February 14, 2020 ; Published: February 17, 2020
*Corresponding author: Professor Abdolreza Jamilian, Department of Orthodontics, TUMS School of Dentistry, Cranio-Maxillofacial Research Center,
Tehran University of Medical Sciences, Islamic Azad University, Tehran, Iran, No 14, Pesiyan Ave., Vali Asr St., Tehran, 1986944768, Iran
Tel/Fax: 00982122011892, e-mail: info@jamilian.net
Copyright: © 2020 the Editorial Council for the Stomatology Edu Journal.
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Stability of skeletal class III malocclusion
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Review Articles
Figure 1. PRISMA flowchart of article
retrieval.
scenario, the surgical treatment has been regarded relapse of bilateral sagittal split osteotomy setback
as the best approach to achieve the best results in surgery is 9.9%-62.1%, and long-term relapse is
adult cases [8]. Post-surgical relapse is one of the between 14.9% and 28.0%, at point B. To the best
major concerns in the correction of skeletal class of our knowledge, there has been no meta-analysis
III malocclusion. It has been shown that there is evaluating the stability of skeletal changes after a
a greater tendency for relapse after bimaxillary combined orthodontic and surgical procedure for
osteotomy [9]. Similarly, LaBanc et al [10] reported treatment of skeletal Class III patients in short- and
that due to increased incidence of relapse, bimaxi- long-term follow ups. The question is: “How much of
llary surgery should only be performed for the treatment effects remains stable by the end of
specific indications; for example two-jaw surgery follow-up?”
has greater relapse than single-jaw surgery. On Objectives: The aim of this study was a meta-analysis
the contrary, Proffit et al [11] found that better of the literature on the stability of skeletal class III
stability and predictable results can be obtained malocclusion.
after two-jaw surgery. Immediate relapse can be Patients often require a combined orthodontic
identified after surgery which may occur due to and surgical approach after bimaxillary surgery.
intraoperative error such as imprecise planning, This meta-analysis was undertaken to ex-
inaccurate osteosynthesis, or failure to fix the joint. plore the parameters related to the skeletal stability
On the other hand, late relapse can be detected in surgical correction of skeletal Class III malocclusion.
once a considerable period has elapsed since the
day of the surgical procedure. Late relapse may 2. MATERIALS AND METHODS
occur due to unstable occlusal relationships, growth
spurts, absence of myofunctional adaptation, or 2.1. Protocol and registration
persistent tongue or orofacial muscle habits [12]. This systematic review was based on a specific
A study [5] revealed that the rate of short-term protocol developed and piloted following the
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Review Articles
Figure 2a. Before surgery T1 - After
a surgery T2, (T1-T2) SNA.
Figure 2b. After surgery T2 - Last
b follow-up T3, (T2-T3) SNA
Figure 2c. Subgroup analysis according
to the follow-up period (SNA).
c
1. Less than 2 years. ; 2. More than 2 years.
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Figure 3a. Before surgery T1 - After
a surgery T2, (T1-T2) SNB.
Figure 3b. After surgery T2 - Last
b follow-up T3, (T2-T3) SNB.
Figure 3c. Subgroup analysis according
c to the follow-up period (SNB).
1. Less than 2 years. ; 2. More than 2 years.
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Figure 4a. Before surgery T1 - After
a surgery T2, (T1-T2) ANB.
b Figure 4b. After surgery T2 - Last
follow-up T3, (T2-T3) ANB.
Figure 4c. Subgroup analysis according
c to the follow-up period (ANB).
1. Less than 2 years. ; 2. More than 2 years.
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Review Articles
Figure 5a. Before surgery T1 - After
a surgery T2, (T1-T2) Overjet.
Figure 5b. After surgery T2 - Last
b follow-up T3, (T2-T3) Overjet.
Figure 5c. Subgroup analysis according
c to the follow-up period (Overjet).
1. Less than 2 years. ; 2. More than 2 years.
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Review Articles Table 1. Eligibility criteria used for the study selection.
Category Inclusion criteria Exclusion criteria
Randomized controlled trials
Controlled clinical trials
Cohort studies Case reports Commentaries
Experimental studies, Systematic reviews or meta-analyses
Study design prospective and retrospective studies descriptive studies, opinion articles, or abstracts
comparing at least two surgical
treatment strategies
Articles written in the English language
Non-growing patients with Class III Patients with cleft lip palate and/or craniofacial
malocclusion syndromes or genetic problems
Participants Follow-up of 6 months or longer Patients with temporomandibular joint disorders
Treatment in growing patients
Mandibular set back Maxillary advancement
Bimaxillary surgery: (including maxillary Patients treated with orthodontic or orthopedic
Intervention advancement and mandibular set back) appliances
Surgery first Studies not concerning surgical long-term stability
Skeletal and dentoalveolar variables
Outcome measured by lateral cephalometric Studies providing no cephalometric measurements
radiographs
Average time of Studies with an average follow-up at Studies with no follow-up
follow-up least 2 years after surgery
Figure 7a. Before surgery T1 - After
a surgery T2, (T1-T2) U1/SN.
Figure 7b. After surgery T2 - Last
b follow-up T3, (T2-T3) U1/SN.
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Review Articles
Figure 8a. Before surgery T1 - After
a surgery T2, (T1-T2) L1/MP.
b Figure 8b. After surgery T2 - Last
follow-up T3, (T2-T3) L1/MP.
guidelines outlined in the PRISMA-P statement was carefully selected and revised for each database.
[13]. Furthermore, the procedure and reporting All keywords used in the search are detailed in Table
followed the guidelines of the Cochrane Handbook 2. This systematic review and meta-analysis was
for Systematic Reviews of Interventions [14] and conducted based on the PRISMA (Preferred Repor-
the PRISMA statement, [15] respectively. ting Items for Systematic reviews and Meta-Analyses)
guidelines [16]. Title-abstract-full text of each article
2.2. Information sources, search strategy, and study was checked independently by two coauthors based
selection on the PRISMA chart.
A literature search was performed using PubMed,
Google Scholar Beta, Scopus, Web of Science, and 2.4. Data collection and data items
the Cochrane Library to identify articles reporting Two authors (AJ and AD) used pre-defined elec-
combined orthodontic and surgical approach tronic sheets to extract study characteristics
for treatment of skeletal class III malocclusion in independently. Three time points were defined:
non-growing patients. The search process was T1 (before surgery), T2 (after surgery), and T3 (the
conducted independently by two coauthors (AJ end of the follow-up). The findings were obtained
and AD) for articles published up to December on the following items: Name of first author, year
2018. All titles and abstracts were evaluated, and of publication, country, number and mean age
duplicate studies were removed. of patients, gender, type of surgery (Mandibular
setback including BSSO or vertical osteotomy)
2.3. Eligibility criteria or (Bimaxillary surgery including Lefort 1 + BSSO
The inclusion and exclusion criteria were established or Lefort 1 + vertical), type of fixation including
prior to the search according to Table 1. Each keyword Rigid Internal Fixation (RIF) or Maxillomandibular
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Review Articles Table 2. Keywords used for each data base search.
Pubmed Web of science Scopus Embase Cochrane
50 7 63 42 3
((((((“Malocclusion, TI=(“Malocclusion, ((TITLE-ABS- ‘malocclusion angle (“Malocclusion, Angle
Angle Class III”[Mesh] OR Angle Class III” OR KEY(“Malocclusion, class iii’:ab,ti OR Class III” OR “class3” OR
“class3”[Title/Abstract]) “class3” OR “class III” OR Angle Class III”) ‘class3’:ab,ti OR ‘class “class III” OR “Maxillary
OR “class III”[Title/ “Maxillary Deficiency” OR OR TITLE-ABS-KEY iii’:ab,ti OR ‘maxillary Deficiency” OR
Abstract]) OR “Maxillary “mandibular protrusion” (“class3”) OR TITLE- deficiency’:ab,ti “mandibular protrusion”
Deficiency”[Title OR “Maxillary retrusion”) ABS-KEY (“class III”) OR ‘maxillary OR “Maxillary retrusion”)
Abstract]) OR “mandibular AND TI=(“Mandibular OR TITLE-ABS-KEY retrusion’:ab,ti AND (“Mandibular
protrusion”[Title/ Osteotomy” OR (“Maxillary Deficiency”) and ‘mandibular Osteotomy” OR
Abstract]) OR “Maxillary “mandibular surgery” OR OR TITLE-ABS- osteotomy’:ab,ti “mandibular surgery” OR
retrusion ”[Title/Abstract]) “bimaxillary surgery” OR KEY (“mandibular OR ‘mandibular “bimaxillary surgery” OR
AND ((((“Mandibular “surgical orthodontics” protrusion”) OR surgery’:ab,ti “surgical orthodontics”
Osteotomy”[Mesh] OR OR “mandibular set TITLE-ABS-KEY OR ‘bimaxillary OR “mandibular set
“mandibular surgery back”) AND TI=(stability (“Maxillary retrusion”))) surgery’:ab,ti back”) AND (stability OR
”[Title/Abstract]) OR relapse) AND ((TITLE-ABS- OR ‘surgical relapse)
OR “bimaxillary KEY (“Mandibular orthodontics’:ab,ti
surgery”[Title/ Osteotomy”) OR TITLE- OR ‘mandibular
Abstract]) OR “surgical ABS-KEY (“mandibular set back’:ab,ti and
orthodontics”[Title/ surgery”) OR TITLE- ‘stability’:ab,ti OR
Abstract]) OR “mandibular ABS-KEY (“bimaxillary ‘relapse’:ab,ti
set back”[Title/Abstract])) surgery” OR TITLE-
AND (stability[Title/ ABS-KEY (“surgical
Abstract] OR orthodontics”) OR
relapse[Title/Abstract]) TITLE-ABS-KEY
(“mandibular set
back”))) AND ((TITLE-
ABS-KEY (stability)
OR TITLE-ABS-KEY
(relapse)))
Fixation (MMF), follow-up after surgery until 2 years, follow-up to identify the source of heterogeneities.
follow-up after surgery until 5 years, SNA, SNB, ANB, To identify the source of clinical heterogeneity,
overjet, overbite, incisor mandibular plane angle susceptible variables including treatment plan,
(IMPA), upper incisor to SN (U1/SN) angle, during gender, country, treatment time, type of surgery,
T1–T2 (surgical effects), T2–T3 (posttreatment type of fixation, and follow-up time were introduced
changes) were recorded. In order to identify the into a meta-regression model. WMD with 95% CI
correlation between relapse and cephalometric was calculated for all variables. The publication
landmarks, meta-analyses were conducted bias was determined using Begg tests. The p-value
between cephalometric landmarks and different of 0.05 was regarded for statistical significance.
variables such as type of surgery (mandibular The changes in seven variables (SNA, SNB, ANB,
setback including BSSO or vertical osteotomy) IMPA, overjet, U1/SN, and L1/MP) during three time
or (bimaxillary surgery including Lefort 1 + BSSO periods [Before surgery (T1), after surgery (T2) and
or Lefort 1 + vertical), type of fixation including last follow-up (T3)] were compared between the
Rigid Internal Fixation (RIF) or Maxillomandibular studies. The summarized data of included studies
Fixation (MMF), follow-up after surgery within 2 and cephalometric measurements of the included
years, follow-up after surgery within 5 years. studies are seen in Tables 3 and 4 respectively. The
The cut-off value of less than 2 years was chosen to results of the statistical analysis for heterogeneity
separate short-term from long-term studies. and the funnel plots are displayed in Figures 2, 3, 4,
5, 6, 7, and 8.
2.5. Statistical analysis
All statistical tests were conducted using the STATA 3. RESULTS
14 (StataCorp LP, College Station, USA). The effects
of bimaxillary surgery or mandibular setback on 3.1. Study selection and characteristics
SNA, SNB, ANB, overjet, overbite, incisor mandibular Of the 165 records resulting from the search strate-
plane angle (IMPA) and upper incisor to SN (U1/ gies, 73 studies were obtained once duplicated
SN) angle, before and after surgery as well as the articles were excluded. Then, 40 papers were re-
last follow-up were measured by weighted mean moved because of their titles and abstracts. In
difference (WMD) and the 95% confidence intervals addition, 20 more were further excluded for not
(CI). The standard error (SE) of the mean difference meeting the exclusion/inclusion criteria. Ultimately,
(MD) for non-reported studies was calculated by the 13 papers met the final selected criteria and were
following formula: SD2 baseline + SD2 final – (2 R* SD selected to conduct the systematic review and
baseline + SD final) and SD=SE*sq(n). Heterogeneity meta-analysis. The manual search did not yield
across studies was assessed using the I-squared any additional material. In case of disagreement,
and the alpha of 0.05 for statistical significance. the authors discussed the controversy until an
The subgroup analysis was based on the time of agreement was reached. Of the 13 studies, 2 of
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Table 3. Characteristics of the included studies in the systematic review.
Observation
Publication Group(s) Participants (Number, sex, age) Type of Surgery Type of fixation Country
period
conventional bimaxillary 14 (7M, 7F) / Mean age (21.5 ± 2.5) Rigid
surgery Le Fort I Osteotomy &
Jeong et al[1], 2018 2 years South Korea
Bilateral IVRO*
surgery first 17 (9M, 8F) / Mean age (20.3 ± 2.2) Wire
IVRO 15 (7M, 8F) / Mean age (22.1 ± 2.3) IVRO Intermaxillary Fixation
Choi et al[2], 2016 2 years South Korea
IVRO + Lefort 1 15 (7M, 8F) / Mean age (24.1 ±4.3) IVRO + Lefort 1 Rigid
Stoma Edu J. 2020;7(1): 52-67
Conventional 20 (13M, 7F) / Mean age (25.3)
Park et al[3], 2016 6 months bimaxillary surgery Lefort 1 & BSSO** Rigid South Korea
Stability of skeletal class III malocclusion
Surgery-first 20 (12M, 8F) / Mean age (22.6)
BSSO with Semi Rigid Fixation 26 /
Aydemir et al[4], 2015 5 years Lefort 1 & BSSO** Semi Rigid and Rigid Fixation Turkey
and Lefort 1 with Rigid Fixation Mean age (17-29)
Bimaxillary Surgery Le Fort 1
Kim et al [5], 2014 1 year 37(20M,17F) / Mean age (23±4) Lefort 1 & IVRO Wire South Korea
and IVRO
23 (14M, 9F)/
Conventional-BSSO SF*** Rigid
Mean age (23 ±6.3)
Kim et al [6], 2014 22 months South Korea
38 (19M,19F)/
Surgery first BSSO Rigid
Mean age (21.6 ±3.5)
Monocortical plates and
screws in each
45 (19M, 26F) / Lefort I & bilateral sagittal
Ko et al [7], 2013 1 year side of the mandible and Taiwan
Mean age (23.2) split osteotomy miniplates in each side of
the maxilla
81 (55M, 26F) /
Jakobsone et al[8], 2011 3 years Lefort 1 + BSSO Lefort 1 + BSSO Rigid Norway
Mean age (25.8 ± 9.5)
IVRO 21(6M,15F) / Mean age (20.2) Lefort 1 + BSSO
Abeltins et al[9], 2011 1 year Wire Latvia
BSSO 30(7M,23F) / Mean age (19.4) Lefort 1 + IVRO
Lefort 1 N/A / Bimaxillary
Iannetti et al [10], 2007 2 years Rigid Italy
Lefort 1 + BSSO Mean age (18-36) Lefort 1
rigid titanium Rigid resorbable plate Rigid resorbable plate
Costa et al [11], 2006 1 year 21 / Mean age (N/A) Italy
rigid resorbable plate Rigid titanium Rigid titanium
25 (13M, 12F) /
Kwon et al [12] , 2000 7 months Lefort 1 and BSSO Lefort 1 + BSSO Rigid Japan
Mean age (24.1)
18 (N\A) /
McCance et al[13], 1992 1 year Lefort 1 +BSSO Lefort 1 + BSSO Wire England
Mean age (N\A)
pISSN 2360-2406; eISSN 2502-0285
Age is reported in years; N/A, Not available; M, Male; F, Female
*IVRO, Intra-oral vertical ramus osteotomy; **BSSO, Bilateral sagittal split osteotomy; SF
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them did not provide us with enough data for the small sample size. The results of the statistical testing
Review Articles meta-analysis and were excluded from the study. for heterogeneity and the corresponding funnel
Performing meta-analysis was only feasible for 11 plots are given in Figures 2c, 3c, 4c, 5c, and 6c.
studies, and these studies were included in our study.
These studies include non-growing patients with 3.3. Risk of bias within studies /publication bias
Class III malocclusion with Follow-up of 6 months No publication bias was determined by using the
or longer. The level of inter-examiner agreement of Begg’s test [in STATA 14 (StataCorp LP, College
data extraction was measured using kappa statistics. Station, USA)].
The level of agreement between the two examiners The results of the Begg’s test for the analysis of small
was assessed using the Cohen kappa scores. The study effect (publication bias) for the measurements
kappa score for study selection was 0.978, indicating of SNA, SNB, ANB, overjet, overbite, U1/SN, and L1/
an excellent level of agreement. The PRISMA flow MP are as follows, respectively: 0.78, 0.33, 0.95, 0.08,
diagram of study selection is outlined in Fig. 1. 0.45, 0.98, and 0.34.
Before surgery T1– After surgery T2, (T1–T2) Figures
2a, 3a, 4a, 5a, 6a, 7a, and 8a. 4. DISCUSSION
Short-term treatment effects included significant
increase in SNA (WMD 1.78, 95%CI:1.42, 2.12), 4.1. Summary of evidence
significant reduction in SNB (WMD -3.95, 95%CI:- This meta-analysis showed some significant relapse
4.50, -3.40), significant rise in ANB (WMD 6.36, in skeletal and dental variables during the follow-up
95%CI:5.59, 7.13), significant growth in overjet period. SNA and overbite increased significantly after
(WMD 8.24, 95%CI: 6.56, 9.92), significant elevation a 2 year-follow-up. On the contrary, SNB increased
in overbite (WMD 1.57, 95%CI: 0.30,2.84), while U1/ significantly before a 2 year-follow-up. Overjet was
SN (WMD -2.34, 95%CI, -6.27, 1.58) and L1/MP (WMD significantly reduced after a 2 year-follow-up. To
2.12, 95%CI:0.43, 3.82) did not show any significant the best of our knowledge, this is the first meta-
changes. After surgery T2– Last follow upT3, (T2–T3) analysis reviewing the stability of skeletal class III
Figures 2b, 3b, 4b, 5b, 6b, 7b, and 8b. malocclusion after bimaxillary surgery or mandibular
The last follow-up showed no significant changes setback. Data from this study revealed that the main
in SNA (WMD 0.06, 95%CI:-.05, 0.16), ANB (WMD relapse in SNA occurred after a 2 year-follow-up but
0.19,95%CI:-0.43 ,0.82), overjet (WMD -0.53, 95%CI: not in less than 2 years. This suggested that SNA
-1.36, 0.30), overbite (WMD 0.20, 95%CI:-0.17, 0.57), relapse often happened after a 2 year-follow-up and
L1/MP (WMD -0.38, 95%CI:-1.67, 0.92), while there was largely associated with the growth of maxilla
was a significant change in SNB and U1/SN (WMD that is a common finding in class III malocclusion.
0.38, 95%CI:0.24, 0.51) and (WMD 2.12, 95%CI:0.43, For SNB, a significant increase was noted before a
3.82) respectively. 2 year-follow-up and not after a 2 year-follow-up.
This relapse in the short-term is due to the growth
3.2. Subgroup analysis of mandible which reportedly can continue even
A subgroup analysis based on the duration of follow- after 18 years of age [17]. Hence, it is important
up: less than 2 years (group 1) and more than 2 years to consider the patient’s age and their related
(group 2) was conducted to identify the source of growth pattern before bimaxillary surgery and/or
the high heterogeneity and the influence of the mandibular setback treatment. Overjet was reduced
follow-up duration. significantly in more than a 2 year-follow-up; this
SNA increased significantly after a 2 year-follow-up relapse is due to an increase in SNB. However, the
[WMD 0.07, 95%CI: 0.03, 0.11)] but no significant extent of overbite increased significantly after 2
changes were noted in less than 2 year-follow-up years. Pre-surgical orthodontic treatment aims to
[WMD -0.02, (95%CI: -0.23, 0.19)]. decompensate incisor inclination toward normal
SNB did not have any significant changes in more values. Orthodontic decompensation allows a
than 2 year-follow-up [WMD 0.03 (95%CI: -0.11, greater surgical correction, and this may be a more
0.18)]; however, it increased significantly in group 1 important factor in the relapse. We should keep in
[WMD 0.76 (95%CI: 0.49, 1.03)]. mind that skeletal relapse is masked frequently by
There were no significant changes in ANB in both compensatory changes in the axial inclination of the
group 2 durations [WMD .047 (95%CI:-0.26,1.20)] or teeth [18-21]. Relapse varies considerably between
group 1 [WMD -0.49 (95%CI:-1.72, 0.74)] durations. patients and surgeons without any known reason.
For overjet, it decreased significantly after a 2 year- It is clear that good surgical training, profound
follow-up [WMD -0.80 (95%CI: -1.23, -0.36)], but experience in orthognathic surgery, and technical
not in less than a 2 year-follow-up [WMD -0.49 refinements by the surgeon are required to have
(95%CI: -1.38, 0.41)]. Overbite grew significantly perfect surgical outcomes with regards to esthetics
in group 2 [WMD 0.50 (95%CI:0.01, 0.98)] and not and stability. The orthodontist should prepare the
in group 1 [WMD 0.03 (95%CI: -0.36, 0.41)]. Only a patient before surgery for a perfect coordination
few studies measured U1/SN and L1/MP; hence, the and leveling and alignment of both dental arches
heterogeneity could not be measured due to the in transverse width, correct decompensation of
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Table 4. Outcomes in terms of cephalometric measurements of the included studies in the quantitative meta-analysis.
Outcome
Article & year Group
After surgery
Before surgery (T1) T1-T2 Last Follow-up (T3) T2-T3
(T2)
SNA: 0.4±2.3
Conventional bimaxillary surgery N/A N/A N/A SNA: -0.1±1
SNB: -4.9±2.1
Jeong et al[1], 2018
SNA: 0.3±2.3
surgery first N/A N/A N/A SNA:0.1±0.9
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SNB: -5.7±2.6
Conventional SNA: - 2.8±1.9 SNA:0.3±1.4
N/A N/A N/A
Stability of skeletal class III malocclusion
bimaxillary surgery SNB: -3.7±1.6 SNB: 0.2±0.8
Park et al[3], 2016
SNA: -2.5±2.3 SNA:0.4±1.3
Surgery-first N/A N/A N/A
SNB: -3.2±1.9 SNB: 0.7±1.0
SNA: 78.9± 2.9 SNA: 82.9±2.5 SNA: 4.1±2.3 SNA:83.0 ±3.0 SNA: 1.1± 0.3
SNB: 83.1± 3.9 SNB: 82.4±2.9 SNB: -1.4±2.6 SNB:81.4± 3.6 SNB: -1±0.4
BSSO with Semi Rigid Fixation and
Aydemir et al[4], 2015 ANB: 24.2±3.1 ANB: 0.5± 2.5 ANB: 5.5±2.3 ANB:1.6 ± 2.2 ANB: 1.1±0.1
Lefort 1 with Rigid Fixation OJ: 27.0± 3.5 OJ: 2.6 ±3.4 OJ: 9.6±3.7 OJ: 3.0 ± 1.0 OJ: 0.4±5.9
OB: 22.3± 2.6 OB: 1.3 ±1.7 OB: 3.1±3.6 OB:1.4 ± 0.6 OB: 0.1±1.2
SNA: 81.4±2.7 SNA: 81.94±2.9 SNA: 0.6+_1.1 SNA: 82±3.1 SNA: 0.1±0.0
Bimaxillary Surgery Le Fort 1 and SNB: 83.8±3.7 SNB: 79±3.2 SNB: -4.9±2.4 SNB: 79.1±3.1 SNB: 0.1±0.0
Kim et al [5], 2014 IVRO U1/SN: 115.1±5.5 U1/SN: 107.9±5.4 U1/SN: -7.2±3.7 U1/SN: 106.3±7.2 U1/SN: 0.6±0
IMPA: 84.9±6.7 IMPA: 83.2±5.9 IMPA: -1.7±3.9 IMPA: 84±5.9 IMPA: 1.2±1.2
SNA: 81±3.8
SNB: 83.5±4.3 SNB: -4.7±1.9 SNB:0.9±0.8
ANB: -2.5±2.8 IMPA: 0±0 IMPA: -8.9±5
Conventional-BSSO N/A N/A
IMPA: 92.6±5.9 OJ: 10.1±3.5 OJ: -0.8±1.2
OJ: -6.2±3.4 OB: 0.1±1.4 OB:0.2±0.6
OB: 0.9±1.3
Kim et al [6], 2014
SNA: 80.5±4.1
SNB: 83.5±4.1 SNB: -4.4±1.3 SNB: 1.1±0.7
ANB: -3±2 IMPA:0.7±2.2 IMPA: -0.6±5.7
Surgery first N/A N/A
IMPA: 82.3±9.3 OJ:9.3±4.4 OJ: -2.3±3.1
OJ: - 4.4±2.9 OB: 0.8±2.1 OB: -0.3±0.9
OB: 0.7±2
SNA: 79.6±3.6 SNA: 3.3±2.1 SNA: -0.1±0.9
SNB: 84.7±5.5 SNB: -4±3 SNB: 1±1.2
Jakobsone et al[8], 2011 Lefort 1 + BSSO ANB: -5.1±4.1 N/A ANB: 7.3±3.4 N/A ANB: -1±1.2
OJ: -7±5 OJ: 9.8±4.6 OJ: -0.8±2
OB: -1.8±3.8 OB: 3.7±3.5 OB: 0±0.7
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SNA: 80.7±3.7
IVRO SNB: 84.9±4.9 N/A N/A N/A N/A
ANB: -4.2±3.3
Abeltins et al[9], 2011
SNA: 79.3±3
BSSO SNB: 83.6±3.7 N/A N/A N/A N/A
ANB: -4.2±3
Jamilian A. et al.
SNA:0.1±0.1
Lefort 1 N/A N/A SNA: 0.1±0.1 N/A SNB:0.1±0.1
ANB:01±0.2
Iannetti et al [10], 2007
SNA:0.1±0.1
Lefort1+BSSO N/A N/A SNA: 0.1±0.1 N/A SNB: -0.5±0.3
ANB: 0.6±0.3
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SNA: 78.4±2.8 SNA: 81.7±2.9 SNA: 3.3±1.6 SNA: -0.1±0.6
SNB: 81.9±3.8 SNB: 80.7±3.7 SNB: -2.2±2.9 SNB: 0.9±1.1
ANB: -3.5±2.7 ANB: 1±2.4 ANB: 5.5±2.8 ANB: -0.9±1.3
Rigid titanium U1/SN: 111.2±7.8 U1/SN:112.7±8.4 U1/SN: -2.3±3.5 N/A U1/SN: 3.9±5.4
IMPA: 88.3±7.1 IMPA: 87.7±7.8 IMPA: -0.2±2.7 IMPA: -0.4±4.1
OJ: -4.6±3.8 OJ: 3.2±1.31 OJ: 7.9±3.5 OJ: -0.1±1.7
OB: 1.1±21 OB: 2.3±1.4 OB: -0.4±2.1 OB: 1.6±1.9
Costa et al [11], 2006
SNA: 80±3.6 SNA: 82.4±3.9 SNA: 3±1.28 SNA: -0.6±1.2
SNB: 82.9±3.3 SNB: 80.3±3.6 SNB: -3.6±1.5 SNB: 1.1±0.6
ANB: -2.9±0.8 ANB: 2.1±1.9 ANB: 6.6±1.4 ANB: -1.7±1.0
Rigid resorbable plate U1/SN: 105.8±7.1 U1/SN: 107.4±7.4 U1/SN:3.1±9 N/A U1/SN: 1.4±3.3
IMPA: 85.6±5.6 IMPA: 86.1±6.5 IMPA:2.4±3.3 IMPA: -1.9±2.9
OJ: -5.1±1.9 OJ: 2±1.0 OJ: 8.2±2.4 OJ: -0.4±0.8
OB: 0.8±2.1 OB: 2.8±0.8 OB: 0.9±2.4 OB: 0.3±1.1
OJ: 9.1±4.6 OJ: -0.6±1.4
Kwon et al [12] , 2000 Lefort 1 and BSSO N/A N/A N/A
OB: 2.5-±3 OB: -0.1±2.0
SNA: 78.2±4.3 SNA: 82.3±3.4 SNA: 4.1±1 SNA: -0.1±0.0
SNB: 83±4.4 SNB: 81.4±2 SNB: -2±2.0 SNB: 0.4±1
ANB: -4.8±1.9 ANB: 1.3±1.2 ANB: 5.9±0.0 ANB: 0.2±0.4
McCance et al[13], 1992 Lefort 1 +BSSO N/A
IMPA: 85±11 IMPA: 83.3±6.3 IMPA: -1±2.0 IMPA: -0.5±0.5
OJ: -4.1±3 OJ: -0.9±1.1 OJ: 2.4±4 OJ: 0.8±0.0
OB: -6.3±3.8 OB: 2.4±1.2 OB: 3.2±3.6 OB: -0.7±0.5
Data are presented as means ± standard deviations
OB, Over bite; OJ, Over Jet, BSSO, Bilateral sagittal split osteotomy; IVRO Intra-oral vertical ramus osteotomy, SF, Surgery-First
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the incisors, control of the surgical splint, and its 5. CONCLUSIONS
Review Articles
newly defined occlusion to allow correct placement
of the mandible during surgery. The etiology of On the basis of this review, we concluded the
relapse is multifactorial, including, but not limited following.
to: the proper seating of the condyles, the extent of 1. Surgical orthodontic improves sagittal skeletal
mandibular setback and maxillary advancement, the and dental relationships but significant relapse
soft tissue and muscles, the mandibular plane angle, during the follow-up period may happen.
the remaining growth and remodeling, the skill of 2. SNA and overbite increased significantly after a 2
the surgeon, and the pre-operative age of the patient year follow-up.
[8]. Proffit et al [22] questioned the stability in ortho- 3. SNB increased significantly before a 2 year follow-
gnathic surgery since the stability of the surgical up with no significant changes after this follow-up.
repositioning of the jaws varies considerably depen- 4. Overjet diminished significantly after a 2 year
ding on the procedure. In their view, the order of follow-up.
importance starts with the direction of movement,
the type of fixation used, and in the end, the surgical CONFLICT OF INTEREST
technique that has been adopted. The authors declare no conflict of interest.
4.2. Limitations FOUNDING
This meta-analysis might be considered a first
This manuscript was partially supported by the University of
step in addressing the stability of skeletal class III
Michigan Graduate Research Fund.
malocclusion after bimaxillary surgery or mandibular
setback. Although this study provided an overview
AUTHOR CONTRIBUTIONS
of the topic, there were several limitations. One main
limitation was the shortage of large and high-quality AJ: conceptualization, study design, study concept,
RCTs. The numbers of relevant research articles and original writing and corresponding author. LN: draf-
patients included in the meta-analysis were not ting, data interpretation, drawings and editing. MT
large enough. and AD: literature review, search design, data gathe-
Furthermore, the sample sizes were diluted due to ring. AF and MA: software programs and statistical analysis. CWW:
too many study variables included (7 cephalometric drafting, data interpretation, critical revision and final approval.
variables at 3 different time points). Hence, the
quantitative analysis cannot accurately reflect ACKNOWLEDGMENTS
real skeletal and dental changes. Additionally, not
The authors report no commercial, proprietary, or financial
every study included looked at all variables further interest in the products or companies described in this article.
complicating the analysis.
Eventually, some studies proposed surgery first THE AUTHOR’S INSTITUTIONAL AFFILIATIONS WHERE THE
WORK WAS CONDUCTED
which were deleted from the analysis; however,
whether the treatment effects of surgery first can Department of orthodontics, Faculty of dentistry, Cranio
be stable remains unclear. Attention should also maxillofacial Research center, Tehran medical sciences, Islamic
be paid to the stability of the treatment effects of Azad University, Tehran, Iran and Department of Periodontics
surgery first. Therefore, future research in this area is and Oral Medicine, School of Dentistry, University of Michigan,
warranted. Michigan, USA.
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Abdolreza JAMILIAN
DDS, PhD, Professor
Department of Orthodontics
Faculty of Dentistry
Cranio-Maxillofacial Research Center
Tehran Medical Sciences
Islamic Azad University
Tehran, Iran
CV
Professor Abdolreza Jamilian is a researcher and specialist in field of Orthodontics. He received his DDS (1991), MSc in
Orthodontics (1998), and Fellowship of Orthognathic Surgery & Craniofacial Syndroms (2010) from the Shahid Beheshti
University in Tehran, Iran. He obtained his European Board of Orthodontics in 2013. Now he is a professor at the Islamic Azad
University in Tehran. His practice is limited to Orthodontics. He has lectured in several international congresses and has been
a consultant for various journals. He has published over 200 original, peer reviewed research and review articles, 15 book
chapters and more than 300 scientific communications. He holds 3 patents with the United States Patent and Trademark Office.
Research interests: (1) Class 3 malocclusion (2) Cleft lip and palate (3) Orthognathic surgery.
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Questions
Review Articles
1. Which one is correct regarding stability after surgery.
qa. Single jaw surgery has greater relapse than two jaw surgery;
qb. Two jaw surgery has greater relapse than single jaw surgery;
qc. There is a controversy regarding the stability of single and two jaw surgery;
qd. None of them.
2. What are the causes of late relapse after orthognathic surgery?
qa. Unstable occlusal relationships;
qb. Absence of myofunctional adaptation;
qc. Persistent tongue or orofacial muscle habits;
qd. All of them.
3. How much of the Class III malocclusions have true mandibular prognathism?
qa. 5% to 10%;
qb. 20% to 25%;
qc. 30% to 50%;
qd. 50% to 70%.
4. How much of the of all class III malocclusions have some degree of maxillary retrusion?
qa. 15%;
qb. 25%;
qc. 50%;
qd. 75%.
www.sido.it
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