Article_6_4_4-Nazari

ORTHODONTICS
EVALUATION OF BONE MINERAL DENSITY USING CONE BEAM COMPUTED




                                                                                                                                                                          Original Articles
TOMOGRAPHY
Mohammad Sadegh Nazari1a , Ahmad Reza Tallaeipoor2b, Ludovica Nucci3c, Amir Ali Karamifar4d, Abdolreza Jamilian5e*                                                    ,
Letizia Perillo3f

1
 Department of Orthodontics, School of dentistry, Mashhad University of Medical Sciences, Mashhad, Iran
2
 Department of Oral and Maxillofacial Radiology, Cranio Maxillofacial Research Center, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad
University, Tehran, Iran
3
 Multidisciplinary Department of Medical-Surgical and Dental Specialties, Dental School, University of Campania Luigi Vanvitelli, Naples, Italy
4
 Department of Orthodontics, School of Dentistry, Semnan University of Medical Sciences, Semnan, Iran
5
 Department of Orthodontics, Cranio Maxillofacial Research Center, Faculty of Dentistry, Tehran Medical Sciences, Islamic Azad University, Tehran,
Iran

a
  Postgraduate Dental Student
b
  DDS, PhD, Professor
c
  Undergraduate Dental Student
d
  DDS, MSc
e
  DDS, PhD, Professor
f
  DDS, PhD, Professor


ABSTRACT                    DOI: https://doi.org/10.25241/stomaeduj.2019.6(4).art.4
                                                                                                                      OPEN ACCESS This is an Open Access
Introduction: Bone mineral density (BMD) is an important factor in the use of                                         article under the CC BY-NC 4.0 license.
anchorage device. This study assessed the amount of bone density in the areas
                                                                                                                      Peer-Reviewed Article
from 2.5 and 8.11 mm from maxillary alveolar to basal bone in Hounsfield units.
                                                                                                                 Citation: Nazari MS, Tallaeipoor AR, Nucci L,
Methodology: The samples included 30 unilateral cleft palate (15 males and 15                                    Karamifar AA, Jamilian A, Perillo L. Evaluation of
females) with the mean age of 14.23±2.5 years and 30 non-clefts (15 males and                                    bone mineral density using cone beam computed
                                                                                                                 tomography. Stoma Edu J. 2019;6(4):241-247
15 females) with the mean age of 14±2.59 years. CBCT was used to estimate the
                                                                                                                 Received: October 18, 2019
values of bone density in Hounsfield units in the cleft and noncleft patients. BMD                               Revised December 11, 2019
was measured in 4 heights (2-5-8-11mm) from alveolar bone to basal bone in                                       Accepted: December 12, 2019
                                                                                                                 Published: December 17, 2019
mesio-distal and bucco-lingual slices in the upper jaw. T-test was used to analyze
                                                                                                                 *Corresponding author:
the bone density values between the cleft and noncleft.                                                          Abdolreza Jamilian
Results: The highest alveolar bone density in the mesio-distal slice was 1004±                                   Department of Orthodontics, Cranio Maxillofacial
                                                                                                                 Research Center, Faculty of Dentistry, Tehran Medical
6 HU between the right and left centrals in the upper jaw in height of 11 mm in                                  Sciences, Islamic Azad University, Tehran, Iran
                                                                                                                 Tel/Fax: 0098-22052228, e-mail: info@jamilian.net
non-cleft patients. The least amount of alveolar bone density in the mesio-distal
slice was 259±29 HU in tuberosity in height of 11 mm in cleft patients. In non-cleft                             Copyright: © 2019
                                                                                                                 the Editorial Council for the Stomatology Edu Journal.
patients, the most amount of bone density was found 1639± 11 HU between the
centrals in height of 11 mm in the bucco-lingual slice.
Conclusions: Bone density in cleft patients was lower than in non-cleft patients
in all areas and maxillary tuberosity showed the lowest bone density in cleft and
non-cleft patients.
Keywords: Cone Beam Computed Tomography; Bone Mineral Density;
Dental Implants; Single-Tooth; Orthodontics.


1. Introduction                                                            has not been broadly used in dentistry because of its
The amount of bone tissue is called bone mineral                           high cost, presence of artifacts in images, high dose
density (BMD)[1]. Assessment of BMD is necessary in                        of radiation and complexity of examination.
many clinical conditions such as oral systemic diseas-                     Recently CT has been replaced by cone-beam com-
es, implant planning and it also has an important role                     puted tomography (CBCT) to evaluate anatomic struc-
for the stability of mini-implants as anchorage [2,3].                     tures and the direct measurement of mineralized tissue
Computed tomography (CT) is a diagnostic method                            [5,6]. CBCT provides suitable image quality conco-
before performing dental implant. It allows accurate                       mitant with a lower exposure dose. Fast scanning
three-dimensional evaluation of anatomical struc-                          time, low cost and a lower number of image artifacts
tures of the bone. It also measures BMD which it                           are the other advantages of CBCT when compared
expresses in Hounsfield units (HU) [4]. Although CT                        to CT [7-9]. CBCT has frequently been used to assess
is a diagnostic tool in medical practice, this method                      the quality of skeletal structures by determination of



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Original Articles



                    Figure 1. (a) Mesio-distal measurement on the palatal side; (b) Mesio-distal measurement on the buccal side.




                    Figure 2. (a) Bucco-lingual measurement on the maxilla; (b) Bucco-lingual measurement on the mandible.


                    mineral density. CBCT has many advantages when                              measured from the alveolar bone crest to basal bone
                    compared with conventional CT, including lower                              in HU obtained by CBCT in unilateral cleft palate and
                    cost, smaller radiation dose, and the need for less                         non-cleft patients.
                    space. CBCT scanning is associated with some draw-
                    backs, such as poor soft tissue contrast, motion arti-                      2. Methodology
                    facts and image noise. Conventional CT may distin-                          The participants in this retrospective research were
                    guish 70% of root fractures, but the higher cost and                        30 unilateral cleft palates (15 males and 15 females)
                    high dose of radiation limit the use of this technique                      with the mean age of 14.23+2.5 years and 30 non-
                    [10]. BMD can be recognized by Gray values acquired                         cleft patients (15 males and 15 females) with the
                    with CBCT as the HU values [11].                                            mean age of 14+2.59 years. The criteria to select the
                    CBCT provides a three-dimensional analysis with                             patients were as follows: no history of serious disease
                    the quantification of the mineral density of jaws in                        affecting oral bones, no periodontal problems, no
                    Hounsfield units (HU) [3]. CBCT is a valuable method                        previous fracture, no history of bone grafting, no pre-
                    for diagnosis and treatment planning especially in                          vious orthodontic therapy, none of the patients were
                    cleft lip and palate patients because it offers better                      on hormone therapy or taking calcium, vitamin D,
                    data about the size and appearance of the anatomic                          fluorides, calcitonin, bisphosphonates, no palatal fis-
                    structures affected by the cleft, the position of miss-                     tula or infection. CBCT of all the patients were taken
                    ing teeth, the amount of BMD, as well as the posi-                          by the same radiologist for orthodontic treatment.
                    tion of mini screw, dental implants and so on. To our                       All unilateral cleft palate patients had palatal clo-
                    knowledge no study compared the BMD of cleft pa-                            sure before the age of 2. The CBCT (New Tom 5G; QR,
                    tients with non-cleft samples.                                              Verona, Italy) was performed to assess BMD in the
                    Therefore, due to the lack of research in this area the                     cleft and noncleft regions in all patients. The images
                    aim of this study was to compare the BMD of inter-                          were obtained at 120 kV and 8 mA. 0.2 mm3 voxel,
                    radicular distances at heights of 2, 5, 8 and 11 mm                         80 mm field of view BMD was calculated using the




 242                                                                     Stoma Edu J. 2019;6(4): 241-247                           www.stomaeduj.com
                        EVALUATION OF BONE MINERAL DENSITY USING CONE BEAM COMPUTED TOMOGRAPHY



Table 1. BMD in Hounsfield units (HU) from the mesio-distal slice in the maxillary arch between teeth and




                                                                                                                     Original Articles
tuberosity.

                       Mesio-distal slice             2 mm            5mm             8 mm            11 mm


     Region                   Group                Mean ±SD         Mean ±SD        Mean ±SD        Mean ±SD

       1-1                  Non-cleft              896±17 **        935±6 **         983±4 **       1004±6 **
                              Cleft                  884±5           923±7            973±5           994±5
       2-1                  Non-cleft               874±7 **        916±5 **         953±6 **        994±5 **
                              Cleft                  862±9           908±8            941±8           984±6
                            Non-cleft               851±6 **        897±25 *         935±7 **        945±5 **
       3-2
                              Cleft                  842±19          882±27           923±9           932±10
       4-3                  Non-cleft               845±25 *         872±28          896±27          915±34
                              Cleft                  832±26          860±29          885±27          904±34
       5-4                  Non-cleft                832±34          857±26          886±22          872±24
                              Cleft                  831±27          845±25          875±23          857±25
      6-5                   Non-cleft                934±61          980±89          954±72          645±50
  Palatal side                Cleft                  913±40          951±37          927±35          634±50
      7-6                   Non-cleft                899±39          934±47          880±37          542±57
  Palatal side                Cleft                  877±59          919±43          868±39          535±50
     6-5                    Non-cleft                825±42          846±38          870±41          643±47
  Buccal side                 Cleft                  814±43          838±35          855±42          626±46
     7-6                    Non-cleft              770±82 **         671±90          773±79          406±81
  Buccal side                 Cleft                 721±63           660±88          759±77          397±79
                            Non-cleft               650±125          566±129         408±98          265±55
     Tuber
                              Cleft                 643±107          539±105         407±64          259±29

** P 01/0>            * P 05/0>

Xoran Cat software version 3.1.62 (Xoran Techno-           molar and first molar (5 and 6); between the first and
logies, Ann Arbor, MI, USA). This software includes        second molars (6 and 7). Mean and standard devia-
an application to outline the selected bone within         tions of BMD were measured for heights of 2-5-8 and
a defined area and to provide the average BMD in            11 mm in cleft and non-cleft patients. T-test was used
HU. Using the Xoran Cat software, version 3.1.62 the       to analyze the bone density values between the cleft
slices were made in the alveolar bone height in the        and noncleft. SPSS 18.0 (SPSS, Inc, Chicago, IL, USA)
range of 2-5-8- to 11 mm from the alveolar crest to        was used for statistical analysis. The differences were
the basal bone in mesio distal slices and in bucco-        considered statistically significant with the p<0.05.
lingual slices on the right and left sides of the max-
illary arch. In other words, BMD was measured in 4         3. Results
heights (2-5-8-11mm) from the alveolar bone to the         The highest alveolar BMD in the mesio distal slice was
basal bone in mesio distal and bucco-lingual slices in     1004± 6 HU between the right and left centrals in the
the following areas. Figures 1 and 2 show the mesio-       upper jaw in height of 11 mm in non-cleft patients.
distal and bucco-lingual measurement respectively.         The least amount of alveolar BMD in the mesio-distal
Between the right and left centrals (1 and 1); be-         slice was 259±29 HU in tuberosity in height of 11 mm
tween the central and lateral incisors (1 and 2); be-      in cleft patients. The highest amount of BMD in the
tween cuspids and first premolars (3 and 4); between       posterior region found was 980± 89 HU which was
the first and second premolars (4 and 5); between the      between the second premolar and the first molar in
second premolar and first molar (5 and 6); between         a depth of 5 mm from the mesio-distal view in non-
the first and second molars (6 and 7); the region distal   cleft patients and it was 927±35 HU in height of 8
to second molars (7D) and tuberosity for both sides        mm in the same slice in cleft patients. The highest
of the upper jaw. These heights were also measured         amount of BMD in the palatal side was 980±89 HU in
on the palatal and buccal sides in mesio-distal slice      5 mm from alveolar crest in non-clefts patients and
only in the posterior region between the second pre-       the lowest one was 626±46 HU in the buccal side in



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                    Table 2. BMD in Hounsfield units (HU) from the bucco-palatal slice in the maxillary arch between teeth and
Original Articles   tuberosity.

                                        Bucco-palatal slice         2 mm                5mm              8mm              11mm


                         Region                 Group             Mean ±SD           Mean ±SD          Mean ±SD         Mean ±SD

                            1-1               Non-cleft            615±5 **           683±4 **          783±6 **        1639±11**
                                                Cleft               607±5              671±6             772±6           1582±26
                            2-1               Non-cleft            684±4 **           764±6 **          845±4 **        1447±10 **
                                                Cleft               673±7              753±9             836±6           1438±10
                            3-2               Non-cleft            756±6 **          848±18 **          903±6 **        1257±10 **
                                                Cleft               744±7             837±6              894±6           1248±10
                                              Non-cleft            825±5 **           924±5 **          963±4 **        1064±4 **
                            4-3
                                                Cleft               819±7              917±7             949±8           1051±8
                            5-4               Non-cleft            934±6 **           993±4 **         1008±9 **          830±20
                                                Cleft               921±7              981±8            1001±9            822±19
                            6-5               Non-cleft           1078±18 **         1159±21 **        1030±9 **         674±105
                                                Cleft              1064±19            1146±20           1018±9           661±104
                            7-6               Non-cleft            1332±43            1439±45         1254±24 **         643±22 *
                                                Cleft              1331±44            1427±45          1209±31            631±19
                          Tuber               Non-cleft            833±34             839±26           365±19 *          262±19 *
                                                Cleft              822±32             750±25            354±17            251±19

                    ** P 01/0>           * P 05/0>

                    11 mm from alveolar crest in clefts samples. Table 1       second premolar and first molar in depth of 5 mm
                    shows the means, standard deviations between the           from the crest of the alveolar bone and also in the
                    assessed areas on cleft and non-cleft patients in me-      bucco-lingual slide, may be between the first and
                    sio-distal slice. The BMD of the anterior region of the    second molars in a depth of 5 mm from the crest of
                    maxilla in non-cleft patients was statistically higher     alveolar bone in cleft and non-cleft patients. The in-
                    than the cleft samples in the bucco-lingual slices in      sertion of mini-implants in this area, considering only
                    all areas. In non-cleft patients, the highest amount of    the highest BMD as a factor for success, would be
                    BMD found was 1639±11 HU between the centrals              more interesting. But one must keep in mind that this
                    in height of 11 mm in the bucco-lingual slice in non-      does not always occur, because other factors may
                    cleft patients. The highest amount of BMD in the pos-      contribute to loosening the mini-implants. For mini
                    terior region was found between the first and second       implant installation there must be adequate cortical
                    molars in a depth of 5 mm from the bucco-lingual           bone thickness and also high BMD. It is considered
                    view in both cleft and non-cleft patients which was        that BMD is a key factor for the stability of mini-im-
                    1439±45 HU and 1427±45 HU respectively. There was          plants as anchorage. BMD should be such so as to
                    no significant difference between the 2 groups in this     favor the mechanical retention of the mini implant in
                    area. The least amount of BMD found was 251±19 HU          a predetermined position. There are many factors for
                    in tuberosity in height of 11mm in the bucco-lingual       losing mini-implants as anchorage and one of these
                    slice of cleft patients Table 2 shows the values ob-       factors is poor density [12-15]. BMD has an important
                    tained for the means, standard deviation between           role in a successful implant. Areas of lesser bone qual-
                    the assessed areas on cleft and non-cleft patients in      ity have exhibited weaker stability and higher failure
                    bucco-lingual slice.                                       rates of dental implants [16,17]. The data which one
                                                                               obtained from this study will serve as guidelines
                    4. Discussion                                              for choosing the best quality of alveolar BMD for
                    The result of this research can be used as additional      the placement of mini implants or dental implants.
                    information to select the most suitable area for an-       There was a progressive increase in BMD from cleft
                    chorage devices such as mini- implants. These find-        to non-cleft patients in all areas. This study showed
                    ings suggest that the best quality of alveolar bone        that the maxillary tuberosity area had a lower BMD
                    density for mini implant installation from the mesio-      and also showed that BMD was greater on the palatal
                    distal view, may be in the posterior area between the      side than the buccal side between second premolars



 244                                                         Stoma Edu J. 2019;6(4): 241-247                   www.stomaeduj.com
                            EVALUATION OF BONE MINERAL DENSITY USING CONE BEAM COMPUTED TOMOGRAPHY



and the first & second molars in both groups. Due to                 tions and limitations of currently used reconstruction




                                                                                                                                        Original Articles
this fact anchorage devices can be applied on the                    algorithms [25].
palatal side. On the other hand, with respect to the
aesthetic concerns of the device, and for greater me-                5. Conclusions
chanical control, mini implants can be inserted in the               BMD in non-cleft patients was higher than in cleft
lingual side[18]. BMD can be measured in HU by CT                    patients in all area; however, the mean BMD in non-
and CBCT [8]. With CT, BMD values are presented in                   cleft patients was significantly greater than in cleft
Hounsfield Unit (HU) based on density of air (-1,000                 patients from the upper left to the right canines in
HU) and pure water (0 HU).The density of cortical                    all areas in the medio-distal slice. Significantly higher
bone ranges from±1,000 to ±1,600 HU values [19].                     BMD was found in the labial cortical plate between
Turkyilmaz et al [20] determined that BMD ranged                     the centrals on the mesio distal direction in depth
from 278 to 1,227 HU in the jaws, with a mean of 751                 of 11 mm from the alveolar crest in cleft and non-
HU. According to Turkyilmaz et al, the variability of                cleft patients; however, the differences between 2
the different amount of DBM in the literature is due                 groups were significant. The highest amount of BMD
to the effect of variables such as age and sex. BMD                  was found between the first and second molars on
varies according the regions of the jaws and may be                  the bucco palatal area 5 mm from the alveolar crest
affected by many factors including osteoporosis, ex-                 in cleft and non-cleft patients and the differences
istence or absence of cleft [21-22].                                 between them were not statistically significant. The
Because of the high dosage of CT and lower dose of                   maxillary tuberosity showed the zBMD.
radiation exposure of CBCT, recently CBCT has been                   The amount of BMD was higher in the palatal side
widely used for craniofacial imaging [23].                           than the buccal side both in cleft and non-cleft pa-
Pripatnanont et al [24] found that the mean BMD                      tients between the second premolar and the first &
after grafting in the cleft site was 426.1±120.1 HU                  second molars.
which was statistically lower than that in the noncleft
site with the mean value of 543.9 ±120.2 HU. Regard-                 Author Contributions
ing the different types of secondary alveolar bone                   MSN: responsible for study design, administration,
grafting in patients with cleft lip and palate, Scalzone             data interpretation, recruitment, statistical analysis,
et al [25] in a systematic review found that the au-                 literature review. ART: responsible for data interpreta-
tologous bone and rh-BMP2 graft showed a similar                     tion, critical revision and final approval of the article.
effectiveness in maxillary alveolar reconstruction                   AJ: responsible for the study concept, study design,
assessing bone graft volume and height, although                     data interpretation, critical revision, writing and re-
the rh-BMP2 graft showed a relative shorter length                   vising the report and final approval of the article.
of hospital stay. The use of BMD using CBCT required                 LN: responsible for the literature review.
high stability and reliability of gray values and a con-             AAK: responsible for data gathering, LP: responsible
sistent correlation between quantitative gray values                 for drafting, data interpretation, critical revision and
and density. Various limitations are associated with                 final approval of the article.
the use of Hounsfield unit values in CBCT. These is-
sues relate to the limited-field of CBCT geometry,                   Acknowledgment
basic radiation physics principles and the assump-                   There is no conflict of interest.




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                                                                                                        Mohammad Sadegh NAZARI
                                                                                                         Postgraduate Student
                                                                                                 Department of Orthodontics
                                                                                                           School of Dentistry
                                                                         Mashhad University of Medical Sciences, Mashhad, Iran



                    CV
                    Maohammad Sadegh Nazari graduated from the Tehran Azad University of Dental School in 2017 and as
                    a resident of orthodontics in 2018 at the Mashhad University of Medical Science. He became a top Iranian
                    student researcher in 2016 and a national student in 2016. He has published 9 articles. He has participated in
                    various conferences and congresses and has had several oral presentation and posters. His scientific interests
                    are focused on orthognathic surgery patients.




 246                                                                   Stoma Edu J. 2019;6(4): 241-247                             www.stomaeduj.com
                        EVALUATION OF BONE MINERAL DENSITY USING CONE BEAM COMPUTED TOMOGRAPHY




Questions




                                                                                                 Original Articles
1. What is the amount of bone tissue?
qa. Hounsfield unit;
qb. Bone mineral density (BMD);
qc. Bone resorption;
qd. Bone remodeling.

2. Which one is used to evaluate anatomic structures and thr direct measurement of
mineralized tissue before dental implant?
qa. CBCT;
qb. HU;
qc. MRI;
qd. CT.

3. What is the highest alveolar bone density in the mesio distal between … in the upper
jaw in height of … mm in … patient?
qa. Right and left centrals, 8, non-cleft;
qb. Central and lateral, 11, non-cleft;
qc. Right and left centrals, 11, non-cleft;
qd. Central and lateral, 8, non-cleft.

4. Which is the highest amount of bone density in the posterior region?
qa. First and second molars;
qb. Second premolar and first molar;
qc. First and second premolars;
qd. Second and third molars.




                                    19 - 20 March 2020
                                  Cairns Convention Centre
                                     www.aso2020cairns.com.au


Stomatology Edu Journal                                                                           247