JIDAM “An Official Journal of IDA - Madras Branch” ©2021. Available
online

ISSN No: 2582-0559

Volume No: 8, Issue No: 2

META ANALYSIS

IMPACT OF ORTHODONTIC TREATMENT ON ALVEOLAR BONE

THICKNESS USING CBCTS: A META ANALYSIS

Dr Adeel Ahmed Bajjad, Dr Navneet Kour*

Department of Orthodontics & Dentofacial Orthopedics, Kothiwal Dental College and Research Centre, Moradabad,

UP, India

*Department of Periodontics, BRS Dental College, Haryana, India

DOI:

1.37841/jidam_2021_V8_I2_01

Address for Correspondence

Dr Adeel Ahmed Bajjad, MDS,

Senior Lecturer,

Department of Orthodontics & Dentofacial Orthopedics,

Kothiwal Dental College and Research Centre, Moradabad,

UP, India

Email id: dr4dentist@gmail.com

Received: 0

8.05.2021 First Published

31.05.2021

Accepted:

28.05.2021

Published:

27.06.2021

ABSTRACT

AIM:

To survey challenges in alveolar bone thickness around

the orthodontically treated teeth estimated with CBCT.

MATERIALS AND METHODS:

An electronic hunt was

directed  in  PubMed,  Scopus,  Embase  and  Cochrane  Library,
utilizing search terms, with no restriction on distribution date, up
to  July  2020.  The  articles  chose  for  examination  included
randomized  controlled  trials,  case-control  studies  and  cohort
investigations  of  patients  treated  with  fixed  orthodontic
appliance,  which  had  estimated  alveolar  bone  thickness  with
CBCT when treated.

RESULTS:

Out of 150 articles, only 50 were related to the

subject.  After  proper  title  and  abstract  reading,  only  9  articles
were found to be fit for the meta-analysis. All the articles were
found to be of medium quality with the change in alveolar bone
thickness  around  cervical  third  in  labial  portion  of  the  teeth,
presenting increases of 0.4-0.64 mm with considerable results on
the palatal sides.

CONCLUSION:

On patients experiencing diverse orthodontic

treatment  strategies,  there  was  a  noteworthy  decrease  in  bone
thickness, for the most part on the palatal side. These findings
were  significant  and  must  be  considered  in  determination  and
arranging  of  tooth development,  so  as  to  forestall  the  event  of
dehiscence and fenestration in alveolar bone.

KEYWORDS:

Alveolar Bone Thickness, CBCT, Orthodontic

Treatment, Thickness

JIDAM “An Official Journal of IDA - Madras Branch” ©2021. Available
online

ISSN No: 2582-0559

Adeel & Navneet: Impact of Orthodontic treatment on Alveolar bone thickness using CBCT

Volume No: 8, Issue No: 2

INTRODUCTION:

Although orthodontic treatment with fixed appliances

has  become  an  essential  piece  of  contemporary
orthodontics,  it  has  additionally  been  related  with  certain
unfriendly impacts including  root resorption,  development
of  white  spot,  and/or  periodontal  ramifications,  including
alveolar bone loss and clinical attachment loss.

1-3

Orthodontic fixed apparatuses make support of

legitimate oral cleanliness increasingly troublesome,
bringing about expanded plaque accumulation and resulting
in mild inflammation of the oral tissues. It has been archived
that fixed machines have a critical effect on both microbial
and clinical intraoral conditions

, which can vary from

patient-patient,

site-site,

and

appliance

specific

characteristics

5,6

and is for the most part observed as

increased probing depth, increased bleeding on probing,
increased crevicular fluid volume, and a shift from aerobic
to anaerobic microbial species

4,5

. It is anyway accepted that

these treatment-actuated changes are for the most part
transient

, are standardized in any event mostly after

removal of the orthodontic appliance

, and are not related

with any enduring hindering impact on the encompassing
periodontal tissues

. A past methodical audit on this point

showed  that  orthodontic  treatment  has  little,  yet  factually
huge,  negative  impacts  to  the  periodontium,  as  far  as
alveolar  bone  loss,  gingival  recession,  and  periodontal
pocket

formation1

concern.

Notwithstanding,

longitudinal estimations of clinical attachment levels remain
the best quality level to measure change in the periodontal
status of patients

and are viewed as a proportion of past

disease activity, and hence an increasingly precise
proportion of history of infection and disease progression
than pocket probing depth.

10,11

MATERIAL AND METHODOLOGY:

SEARCH STRATEGY:

A precise survey of the reference index was led as per

PRISMA (Preferred Reporting Items for Systematic
Reviews and Meta-Analyses) proposals

. Searches were

made in the PubMed, Scopus, Embase and, Cochrane

Library databases, utilizing a similar pursuit terms in each,
with no impediment on distribution date, up to and including
15th July 2020.

The catchphrases utilized in the database search

through consolidated terms (including MeSH and non-
MeSH terms) with Boolean administrators (and/or)
additionally. The pursuit utilized the terms such as alveolar
bone

thickness/density

and

orthodontic

treatment.

Furthermore, CBCT, trailed by alveolar bone thickness or
tooth development and CBCT was utilized.

INCLUSION CRITERIA:

The survey acknowledged articles in any language.

Randomized  controlled  trials,  case-control  studies,  and
cohort studies were incorporated, as were both retrospective
and  prospective  examinations.  The  incorporation  criteria
were  articles  exploring  patients  in  permanent  dentition
treated  with  fixed  appliances,  which  experienced
extractions and who encountered incisor retractions.

A further rule was the accessibility of CBCT checks

estimating alveolar bone thickness on the labial and, palatal
sides  of  the  teeth  both  prior  and  after  treatment.  The
determination of articles was made on the basis of titles and
abstracts,  the  reviewers  read  the  full  articles  and  recorded
the reasons for approval and dismissing of any article.

EXCLUSION CRITERIA:

Systematic reviews, meta-analysis, case reports, case

series,  literature  reviews  and  editorials  were  excluded.
Articles  that  included  patients  treated  with  orthognathic
surgical procedure or patients with congenital disorders and
additionally any systemic disease were not included.

EXTRACTION OF DATA AND ANALYSIS OF THE
VARIABLES:

The variables analyzed in each article included the type

of  study,  sample  size,  demographic  feature  (sex,  age),
follow-up  time,  CBCT  used,  results  obtained,  and
conclusion (Table 1).

Table 1: variable analysis

Authors

Year

Type

Study

N
(M/F)

Mean
Age
(Years)

Follow Up
Time

CBCT used

Conclusion

Sarikaya
et al

2002

retrospective

14.1

2.3

T1:

pre-

treatment
T2:

months

Tomoscan

SR7000:

Philips,

Best,

the

Netherlands.

On  the  labial  side,
there  have  been  no
noteworthy  changes
in bone thickness.

JIDAM “An Official Journal of IDA - Madras Branch” ©2021. Available
online

ISSN No: 2582-0559

Adeel & Navneet: Impact of Orthodontic treatment on Alveolar bone thickness using CBCT

Volume No: 8, Issue No: 2

post-
retraction

(120kV,

175

mA,

with a window width
set a 5000, 1500HU).

On the palatal side, a
decrease

bone

thickness was seen in
S1 and S2.

Ahn

2013

retrospective

37
(0/37)

26.6±8.5

1.8±0.4

Implagraphy,  Vatech,
Seoul Korea

(12x9cm FOV, 90kV,
4.0  mA,  0.2  mm
isotropic voxel, 24 sec
output time)

The alveolar bone
thickness of all the
maxillary

incisors

fell fundamentally.

Picanço
et al

2013

retrospective

12
(6/6)

G1:

(1/5)
15.83 ±
4.87
G2:
6(5/1)
18.26 ±
6.42

G1: 2.53 ±
0.49
G2: 2.39 ±
0.66

Not specified

No adjustments in
alveolar

bone

thickness  happened
aside  from  inside
vestibular  S3  of  the
maxillary  incisors  in
bunch G1,  where the
thickness reduced.

Nayak
Krishna
et al

2013

retrospective

10(0/1
0)

15 ± 3

T1:

pre-

treatment
T2:

months
post-
retraction

clinical

frameworks
(120  kV,  160MVA,
with  window  width
set  at  2444  level  364
from spiral CT)

The adjustments in
alveolar

bone

thickness

the

labial side weren't
huge.
On the palatal side,
the progressions were
huge in S1 and S3.

Yodthon
g et al

2013

retrospective

23
(2/21)

20.4

2.7

T0:

pre-

retraction
T1:

months
post-
retraction
Follow-up
time:

months

Veraviewepocs

Morita MPG (80 x 40
mm  FOV,  80kV,  5
mA, 0.125 mm voxel,
7.5  second  exposure
time).

Labial  alveolar  bone
thickness  in  S3  and
all  out  alveolar  bone
thickness  in  S1  both
expanded
fundamentally.

Almeida
et al

2015

Randomized
controlled trial

18.58 ±
5.43
(test)21.6
1 ± 6.69
(control)

I-CAT

Imaging

Sciences
International,  22x16-
cm field of view, 120
kVp,
36 mA, 0.4-mm voxel
size  and  40-second
sweep time.

There was critical
lessening

mandibular

buccal

bone  thickness  and
cross-over  width  of
buccal  bone  in  the

two gatherings.

Thongud
omporn
et al

2015

Case series

15(4/1
1)

9.9 ± 1.0
years

Veraviewepocs

Morita MPG, 80 kV,
5 mA, 7.5 second
presentation

time,

0.125 mm voxel goal,
80 x 40 mm field of
view.

Changes  in  labial
bone  thickness  at  all
levels  weren't  not
critical.

Jian-
Hong Yu
et al

2016

observational

20-25

T0:before
the
orthodonti
c treatment
T1:  at  the
end  of  7
months  of
active

120 kVp, 47 mA, 250-
mm voxel goal, and
16-cm field-of-view.

the

distinction

somewhere  in  the
range  of  T0  and
T1revealed  23.36%
decrease

bone

thickness, while the
distinction
somewhere  in  the
range  of  T1  and  T2

JIDAM “An Official Journal of IDA - Madras Branch” ©2021. Available
online

ISSN No: 2582-0559

Adeel & Navneet: Impact of Orthodontic treatment on Alveolar bone thickness using CBCT

Volume No: 8, Issue No: 2

orthodonti
c treatment
T3:

after

several
months
(20–24
months) of
retention
T2.

indicated a 31.81%
expansion in bone
thickness.

The

distinction
somewhere in the
range of T0 and T2
(when

treatment)

affirmed

that

the

bone

thickness

generally

stayed

steady however, the
bone

thickness

around 11% of the
teeth

didn't

recuperate to just
80% of its
unique state.

Fabian
Jäger et
al

2017

Retrospective

43(24/
19)

25±5

I-CAT

Generation  (Imaging
Sciences
International,
Hatfield,  Pa),  with  a
field of perspective on
13  ×  16  cm  and  a
picture  goal  of  0.25-
mm voxel size.

90% of patients more
youthful

than

demonstrated
decreased

bone

stature of least one
tooth.

QUALITY APPRAISAL:

The nature of the articles was classified using

CONSORT measures as adjusted by Mattos et al. in 2011

which have been utilized by a few authors in various

systematic

reviwes

14-16

This

meta-analysis

used

CONSORT  criteria  as  for  assessing  the  quality  of  the
methodology,  design,  execution  and  examination  of  each
article and arranging them into three levels: low, medium or
high quality (Table 2 and Fig 2).

TABLE 2: Representing quality appraisal.

Authors

Blind

Control

Group

Inclusion/Excl

usion

Statistic

Follo

w Up

Dropouts

Limitations

Total

Sarikaya et al

3.5

0.5

3.5

Ahn et al

0.5

3.5

Picanço et al

Nayak Krishna

et al

0.5

3.5

Yodthong et

Almeida et al

Thongudompor

n et al

Jian-Hong Yu

et al

0.5

3.5

Fabian Jäger et

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online

ISSN No: 2582-0559

Adeel & Navneet: Impact of Orthodontic treatment on Alveolar bone thickness using CBCT

Volume No: 8, Issue No: 2

Fig 1: Representing the quality appraisal of the articles

RESULTS:

SELECTION OF ARTICLES:

The underlying database search distinguished 150

articles: 50 in Pubmed, 48 in Embase, 42 in Scopus, and 10

in  the  Cochrane  Library.  Of  these,  100  were  found  to
possess similar content, leaving 50. At the point  when the
titles and abstracts were read, only 9 articles were found to
be  fit  for  the  meta-analysis  and  rest  of  41  articles  were
dismissed  because  they  didn’t  meet  the  consideration
measures (Fig: 2).

Fig 2: PRISMA flow chart. Moher D, Liberati A, Tetzlaff J, Altman DG, The PRISMA Group (2009). Preferred Reporting Items

for Systematic Reviews and Meta-Analysis: The PRISMA Statement.

QUALITATIVE ANALYSIS:

Each article was reviewed and was found to be of

moderate quality as per the rules proposed by Mattos et al

Four  concerned  Angle  class  I  patients  with  twofold
distension  who  experienced  extraction  of  the  four  first
premolars,  while  the  rest  of  the  work  considered  class  II
division  1  patients  who  experienced  extraction  of  the
maxillary first premolars

and one with class III division

The principle controlled assessment was by Picanço et al.,
who treated case gathering of class II by extractions of the
maxillary first molars with a benchmark group of patients

who were treated without extractions.

As far as the time

between CBCT scans, Yodthong et al. performed an initial
CBCT (T0) and a final CBCT (T1) a half year after
withdrawal of the incisors.

Ahn et al. performed out the

last CBCT after space closure, without indicating the time

Sariyaka et al

and, Nayak et al

performed the last CT

three months after incisor withdrawal while Picanco

et al.

performed out the final CBCT check subsequent to
completion orthodontic treatment, year and a half after the
underlying CBCT check. Almeida et al

performed CBCT

7 months after treatment onset (T2) while in Jian-Hong Yu
et al

study each patient underwent 3 dental CBCT scans:

3.5

total quality appraisal

Articles found through various search engines n=150

Article removed due to similar content n=100

Articles read for title and abstract n=50

Full text articles eligible n=9

Articles removed n=41 for not answering the research question

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online

ISSN No: 2582-0559

Adeel & Navneet: Impact of Orthodontic treatment on Alveolar bone thickness using CBCT

Volume No: 8, Issue No: 2

before treatment (T0); at the end of 7 months of active
orthodontic treatment (T1); after several months (20–22
months) of retention (T2) and Fabian Jager et al

performed

CBCTs in patients with multibracket appliances for at least
1 year.

The teeth where the alveolar bone thickness was

estimated were upper incisors and canines18, the four upper
incisors

19, 21

, or the four upper and lower incisors

, 20.

With respect to techniques utilized, Ahn et al., Sariyaka et
al. and, Nayak et al. treated patients with extraction of the
first premolars and maximum anchorage

, while Picanço et

al., Jian et al, Fabian et al, Yodthong et al. didn't indicate the
kind  of  anchorage  utilized.    Yodthong  et  al.  isolated  the
patients  into  two  sub-groups  concurring  to  their  root
development, utilizing sliding mechanics in 11 patients and
loop closure mechanics in 12 patients. Picanço et al didn't
express the space conclusion technique utilized.

The technique used to quantify alveolar bone

thickness  which  was  equivalent  in  all  the  nine
investigations. Labial (Vb) and palatal (Pt) thicknesses were
evaluated  utilizing  CBCT  pictures,  isolating  the  root  with
equivalent lines at 3 mm ranges from the cemento-enamel
junctions to the most elevated point. Along these lines, the
estimations  were  made  in  the  cervical,  central  and,  apical
thirds  and  in  the  full  scale  tooth  underneath  the
cementoenamel junctions.

Picanço et al.

who grouped patients into two, found

that in the group that experienced extraction of the maxillary
first  premolars  and  in  the  control  group  without  any
extractions,  the  former  group  patients  demonstrated  more
retraction  of  the  maxillary  incisor  and  a  more  vertical
position,  while  the  latter  patients  demonstrated  more
noteworthy labialization and distension of the incisors. The
bone thickness in the labial cervical third was greater in first
group than in second group patients. Yodthong et al.

found

that  adjustments  in  the  gathering  of  patients  treated  by
withdrawal  with  tipping  were  more  noteworthy  in  the
palatal cervical third of the incisors (r=0.6; p=0.006), while
the  adjustments  in  alveolar  bone  thickness  were  more
negative in the gathering treated by withdrawal with force
(r=-0.3; p=0.031).

Sariyaka et al.

found that the changes in maxillary

labial bone thickness was not factually greater. The width of
the  bone  labial  to  the  maxillary  left  lateral  incisor
diminished essentially in the center fragment (S2) (p<0.05).
As to upper bone thickness lingual to the incisors, the apical
section  (S3)  estimations  indicated  negligible  change,
however the estimations at the cervical (S1) and center (S2)
section levels contrasted essentially after some time.

Almeida et al

found significant mandibular

expansion in both the groups with a significant decrease in
mandibular buccal bone thickness and transversal width of
buccal bone.

Thongudomporn et al

although found a statistically

significant decreases in palatal and total bone thickness at
the S2 and S3 level (P < .05), the amounts of these changes
were clinically insignificant, ranging from 0.34 to 0.59 mm.
Jian-Hong Yu et al

used CBCT was used to measure the

changes  in  bone  density  around  6  teeth  in  the  anterior
maxilla before and after orthodontic treatment. Each patient
underwent  3  dental  CBCT  scans  and  found  that,  the  bone
density around 10% of the teeth in anterior region could not
recover  to  80%  of  its  state  from  before  the  orthodontic
treatment. Fabian Jäger et al

found a combined (facial and

lingual) change in bone thickness averaged −0.56 ± 0.7 mm
at 5 mm apical to the CEJ, and −0.69 ± 0.9 mm at 10 mm
apical to the CEJ. Lingual bone thickness 10 mm apical to
the CEJ decreased significantly by an average of −0.4 ± 0.78
mm and was greater than the treatment-related bone
thickness decrease observed at other sites.

Ahn et al., Nayak et al., and Picanço et al. discovered

a decline in alveolar bone thickness in all the palatal sections
of the central incisor, though Yodthong et al. also, Sariyaka
et  al.  simply  found  more  noteworthy  reductions  in  the
cervical area on the palatal side of the incisors. On the labial
side,  Picanço  et  al.  discovered  a  higher  augmentation  in
bone  thickness  in  the  cervical  zone  and  Ahn  et  al.  in  the
inside piece.

DISCUSSION:

Barely any examinations have researched the

utilization  of  CBCT  to  enroll  the  adjustments  in  alveolar
bone  thickness  around  the  incisors  that  happen  in  cases
treated  with extractions and,  all at once  withdrawal of the
incisors. One explanation behind this  is the moral issue of
radiation presentation, as this requires presenting the patient
to  two  radiographic  assessments;  another  is  the
methodological decent variety between the couple of studies
that have been distributed.

Work is in progress to diminish the radiation produced

by  CBCT  machines,  the  same  numbers  of  the  patients
analyzed  by  this  strategy  are  youngsters,  who  are  more
susceptible to the impacts of radiation. For this reason, it is
imperative  to  keep  up  an  ideal  harmony  between  the
requirement  for  sufficient  picture  quality  and  radiation
portion.

In spite of the fact that CBCT scanners can catch an

exact 3D picture of the dentoalveolar complex, it is critical

ISSN No: 2582-0559

Adeel & Navneet: Impact of Orthodontic treatment on Alveolar bone thickness using CBCT

Volume No: 8, Issue No: 2

to choose cases that truly will profit by CBCT assessment
also,  to  survey  marginal  cases  cautiously.  These  cases
incorporate alveolar bone phenotypes that are clinically as
well  restricted  to  oblige  labio-lingual  displacements,
patients  with periodontal  diseases,  cases that require tooth
development  past  as  far  as  possible,  including  impacted
teeth that require a choice with respect to whether to extract
or not.

Fuhrmann et al.

demonstrated that quantitative

evaluation of alveolar cortical bone utilizing computerized
tomography (CT) is practical over a base bone thickness of
0.5  mm  and  acquired  outcomes  that  were  factually  like
histological  estimations.  Various  authors  have  discovered
that palatal development of the incisors limits the alveolar
bone  on  the  palatal  side

17,20

. Few authors have even

discovered a 1 mm decrease in alveolar bone thickness
between pre-treatment and post-treatment estimations

As per Handelman, bone loss can be impacted by

treatment  including  extractions  and  the  measure  of  force
utilized  in  orthodontic  movement.  Dehiscence  also,
fenestration are two delayed consequences that can happen
at  the  point  when  incisors  are  retruded;  distension  of  the
maxillary  incisors  can  prompt  dehiscence  of  the  alveolar
cortical bone on the labial side, while withdrawal influences
it on the palatal side29. Picanço et al.

got huge difference

in  bone  thickness  between  the  two  groups  in  the  labial
cervical  third,  which  expanded  by  0.67  mm  in  G1  yet
diminished by 0.06 mm in G2. There was no understanding
between  the  investigations  as  respects  the  planning  of  the
final  CBCT  check.  Ahn  et  al.  performed  the  scans  once
space closure had occurred; Picanço et al. toward the finish
of  orthodontic  treatment,  around  year  and  a  half  after  the
underlying closure.

These distinctions could prompt contrasts at long last

results, as certain authors, for example, Vardimon et al.

have contended that the cortical plate of alveolar bone can
experience rebuilding during treatment, changing its shape
also,  position.  This  stands  out  from  the  speculation  put
forward  by  Handelman,  who  contended  that  there  are
constraints  on  tooth  development  brought  about  by  the
cortical  plates  and,  indicated  that  bone  rebuilding  is
conceivable  during  tooth  development,  instigated  by
organic powers

Dentoalveolar anatomy builds up the restrictions of

orthodontic  tooth  movement,  and  the  bone's  ability  for
adjustment  during  tooth  development,  just  as  its
morphology  when  the  teeth  have  arrived  at  their  last
position

. As we would like to think, deciding if bone goes

with teeth during withdrawal and whether the bone is
equipped for redesigning or not legitimizes utilizing CBCT

both before and after orthodontic treatment. The results
indicated that palatal development of the maxillary incisors
lessened the palatal alveolar bone. This finding can't resist
repudiating De Angelis, who ensured that alveolar bone has
a bowing limit.

In the current examination, the maxillary

bone thickness didn't remain the proportional anyway
reduced.

LIMITATIONS:

Further examinations are required with controlled and

blind  investigations  to  study  cases  from  the  beginning  of
treatment and look  for the changes in the bone before and
after  treatment.  The  current  study  possessed  a  few
constraints as the sample size in every study is small; there
is shift in methods used to measure the bone thickness.

CONCLUSION:

Regardless of the methodological variances between

the investigations studied, it might be expressed that a
noteworthy increment in alveolar bone thickness happens in
the cervical third on the labial side of the central incisor after
orthodontic treatment around 0.4-0.64 mm.

FINANCIAL SUPPORT AND SPONSORSHIP

Nil

CONFLICT OF INTEREST:

There are no conflicts of interest.

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