ORIGINAL ARTICLE

Transverse dental compensation in

relation to sagittal and transverse skeletal
discrepancies in skeletal Class III patients
Jaechan Ahn,a Sung-Jin Kim,a Ji-Yeon Lee,b Chooryung J. Chung,c and Kyung-Ho Kimc
Seoul and Goyang, Gyeonggi-do, Korea

Introduction: The purposes of this study were to compare the buccolingual inclinations of the posterior teeth in
skeletal Class III patients with and without facial asymmetry with those of skeletal Class I patients and to inves-
tigate their relationships with sagittal and transverse skeletal discrepancies. Methods: Sixty-three skeletal Class
III adult patients were divided into 2 groups according to the degree of menton deviation: a symmetry group with
deviation less than 2 mm (n 5 30), and an asymmetry group with deviation greater than 4 mm (n 5 33). The con-
trol group comprised 25 skeletal Class I patients. The buccolingual inclinations of the posterior teeth measured
on cone-beam computed tomography images were compared among the 3 groups, and regression analysis was
performed to investigate the relationships between the inclinations and the sagittal and transverse skeletal
discrepancies. Results: The symmetry group showed greater buccal inclinations of the maxillary posterior teeth
and lingual inclinations of the mandibular second molars than did the control, and this was correlated with the
ANB angles. The deviated sides in the asymmetry group showed the greatest transverse dental compensation,
which was correlated with menton deviation, whereas the nondeviated sides showed no significant transverse
dental compensation. Conclusions: Transverse dental compensation is closely related to sagittal and trans-
verse skeletal discrepancy in skeletal Class III patients. (Am J Orthod Dentofacial Orthop 2017;151:148-56)

T
he buccolingual inclinations of the posterior teeth the occlusal plane on dental casts rarely coincide with
are critical for establishing an ideal occlusion.1,2 It the inclination of the roots.10 A posteroanterior cephalo-
is a fundamental factor when determining the gram may show the inclination of the roots, but super-
prescription of a straight-wire appliance.3 In this regard, imposition of the anatomic structures and the teeth
the American Board of Orthodontics Objective Grading decreases the reliability of this method.11,12 Recently,
System includes an evaluation criterion for buccolingual cone-beam computed tomography (CBCT) has enabled
inclination of the posterior teeth.4 evaluation of the mesiodistal angulation and the bucco-
Traditionally, buccolingual inclination of the poste- lingual inclination of the whole tooth, including crown
rior teeth has been determined using either dental and roots.13
casts5-8 or posteroanterior cephalograms,9 but both Transverse discrepancy is a common problem and
methods have inherent limitations. The inclinations us- more frequently found in skeletal Class III patients.14
ing the tangent point of the buccal crown contour and This is not only because some skeletal Class III patients
have an underdeveloped maxilla and an overdeveloped
mandible with a low tongue posture, resulting in an ab-
a
Department of Orthodontics, School of Dentistry, Yonsei University, Seoul, solute transverse discrepancy, but also because the rela-
Korea.
b
Department of Orthodontics, National Health Insurance Service, Ilsan Hospi- tive forward position of the mandible leads to a relative
tal, Goyang, Gyeonggi-do, Korea. transverse discrepancy.15 Labiolingual inclinations of
c
Department of Orthodontics, Gangnam Severance Hospital, Institute of the maxillary and mandibular anterior teeth are a major
Craniofacial Deformity, College of Dentistry, Yonsei University, Seoul, Korea.
All authors have completed and submitted the ICMJE Form for Disclosure of dental compensation for a sagittal skeletal discrepancy
Potential Conflicts of Interest, and none were reported. in skeletal Class III patients,16,17 so that posterior teeth
Address correspondence to: Kyung-Ho Kim, Department of Orthodontics, Gang- also show a transverse dental compensation in patients
nam Severance Hospital, Institute of Craniofacial Deformity, College of Dentistry,
Yonsei University, 211 Eonjuro, Gangnam-gu, Seoul 135-720, Korea; e-mail, with a transverse skeletal discrepancy. The pattern of
khkim@yuhs.ac. transverse dental compensation is more complicated
Submitted, January 2016; revised and accepted, June 2016. when there is facial asymmetry, which is found in
0889-5406/$36.00
Ó 2017 by the American Association of Orthodontists. All rights reserved. nearly half of skeletal Class III patients.18,19
http://dx.doi.org/10.1016/j.ajodo.2016.06.031 Understanding the mechanism of transverse dental
148
Ahn et al 149

Table I. Patient characteristics and demographic data in the groups

Skeletal Class III,
Skeletal Class I Skeletal Class III, symmetry asymmetry (n 5 33)
(n 5 25) (mean 6 SD) (n 5 30) (mean 6 SD) (mean 6 SD) Multiple comparison
Age (y) 22.7 6 5.31 22.9 6 4.16 21.7 6 3.77
ANB (
) 2.6 6 0.89 1.9 6 1.53 1.7 6 1.60 S 5 AS \ I
Me deviation (mm) 1.2 6 0.64 1.0 6 0.51 8.4 6 3.09 S 5 I \ AS

Data were analyzed by 1-way ANOVA and multiple comparisons with the Bonferroni test at a significance level of P \0.001.
ANB, A-point–nasion–B-point angle; Me, menton; S, skeletal Class III, symmetry; AS, skeletal Class III, asymmetry; I, skeletal Class I.

compensation is crucial when planning appropriate of the posterior teeth, (6) no systemic disease, and (7)
camouflage and presurgical orthodontic treatment for no cleft lip or palate or temporomandibular joint disease.
such patients, because whether to expand or constrict The subjects were divided into groups according to the
the maxillary or mandibular arch largely depends amount of menton (Me) deviation from the midsagittal
on the buccolingual inclination of the posterior teeth plane measured in 3-dimensional (3D) CBCT images:
and the preexisting transverse dental compensation. (1) skeletal Class III, symmetry, with Me deviation less
Several studies have investigated transverse dental than 2 mm (group S); and (2) skeletal Class III, asymme-
compensation in skeletal Class III patients with facial try, with Me deviation greater than 4 mm (group
asymmetry using computed tomographic images.20,21 AS).19,22 Twenty borderline cases of Me deviation
However, these studies have either lacked a skeletal between 2 and 4 mm were excluded from the study.
Class I control group or a skeletal Class III group Finally, 30 patients were enrolled in group S (17 men,
without facial asymmetry. Transverse dental 13 women) and 33 patients in group AS (15 men, 18
compensation is affected by both sagittal and women).
transverse skeletal relationships, so it is necessary to The control group (group I) comprised 25 patients
compare a skeletal Class I group with skeletal Class (11 men, 14 women) selected by the following criteria:
III groups with and without facial asymmetry to (1) ANB between 1
and 4
and Me deviation less than
show the mechanism fully. Moreover, previous 2 mm, (2) anterior crowding less than 4 mm, (3) no
studies have focused only on the first molars, when buccal or lingual crossbite of posterior teeth, and (4)
transverse dental compensation affects all posterior other criteria the same as above. Table I summarizes
teeth, and the pattern of compensation may differ the patients’ characteristics.
from tooth to tooth. The CBCT scans (PaX-Zenith 3D; Vatech, Gyeonggi-
The aims of this study were to compare transverse Do, Korea) were performed under the following condi-
dental compensation patterns of the posterior teeth be- tions: 120 kV, 10 mA, and voxel size of 0.3 mm. The
tween skeletal Class III patients with and without facial scanned images were saved as digital imaging and
asymmetry and skeletal Class I patients and to investi- communication in medicine (DICOM) files and recon-
gate their relationships with sagittal and transverse skel- structed into 3D images using the OnDemand 3D soft-
etal discrepancies. ware program (version 1.0; Cybermed, Seoul, Korea).
The reconstructed 3D images were reoriented using the
MATERIAL AND METHODS Frankfort horizontal plane as horizontal and midsagittal
This study was approved by the institutional review planes passing through nasion and basion and perpen-
board of Gangnam Severance Dental Hospital (No. 3- dicular to the Frankfort horizontal plane. Landmarks
2015-0091) in Seoul, Korea. The CBCT scans of patients and reference planes are defined in Table II and
who visited its Department of Orthodontics from 2011 Figure 1.23,24
through 2014 were screened to select the experimental Me deviation was measured as the distance between
and control groups. Me and the midsagittal plane. Since the amount of Me
Eighty-three skeletal Class III subjects who satisfied deviation was not zero in all patients, the deviated side
the following criteria were included in the experimental was defined as the side toward which the Me was devi-
group: (1) age over 18 years and without previous ortho- ated in relation to the midsagittal plane, and the other
dontic treatment, (2) ANB angle less than 0
, (3) fully side was defined as the nondeviated side.
erupted permanent premolars and molars without To measure the buccolingual inclination of the pos-
ectopic eruption or apparent crowding, (4) no missing terior teeth, long-axis planes were defined as planes
or extracted teeth, (5) no crowns or cuspal restorations perpendicular to the midsagittal plane and passing

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150 Ahn et al

Table II. Landmarks, reference planes, and angular measurements

Definition
Landmark
N (nasion) Middle point between frontal bone and nasal bone
Ba (basion) Most anterior point of foramen magnum
Or (orbitale) Lowest point of lower margin of orbit
Me (menton) Most inferior point on symphysis of mandible
Po (porion) Most superior point of external auditory meatus
Reference planes
FH (Frankfort horizontal) plane Plane passing through right porion, left porion, and midpoint of left and right orbitale
Midsagittal plane Plane perpendicular to FH plane, passing through nasion and basion
Angular measurements
Long-axis plane Plane perpendicular to the midsagittal plane and passing through the mesial cusp and mesial root apex
in molars and the cusp tip and root apex in premolars
Maxilla
Long axis, multirooted premolar and Line connecting the groove between the buccal and palatal cusps and the furcation of the roots
molar
Long axis, single-rooted premolar Line connecting the groove between the buccal and palatal cusps and the root apex
Reference line FH plane in the long-axis plane shown as a line
Mandible
Long axis, premolar and molar Line connecting the groove between the buccal and lingual cusps and the root apex
Reference line Tangent line to the inferior border of the mandible

through the mesial cusp and mesial root apex of the mo- discrepancy (Me deviation) on the buccolingual inclina-
lars, and the cusp tip and root apex of the premolars. tion of the posterior teeth. All statistical analyses were
Buccolingual inclinations were measured on the long- performed with Statistical Package for the Social Sci-
axis planes as an angle between the long axis of each ences software (version 20; IBM, Armonk, NY). A P value
tooth and the Frankfort horizontal plane for the maxil- less than 0.05 was considered to be statistically signifi-
lary teeth and a line connecting the mandibular inferior cant.
borders on both sides for the mandibular teeth (Table II;
Figs 2 and 3). Figure 4 is representative CBCT images at RESULTS
the long-axis planes of a patient in group I, showing the The ICC values ranged from 0.931 to 0.948 for intra-
buccolingual inclinations of the posterior teeth. observer reliability and from 0.908 to 0.925 for interob-
server reliability, indicating excellent reproducibility of
Statistical analysis the measurements. There was no significant difference
All buccolingual inclinations on the CBCT images in buccolingual inclinations between the deviated and
were remeasured after a 2-week interval in 20 patients nondeviated sides in groups I and S (P .0.05). In group
selected at random by 2 authors (J.A. and S.J.K.). The AS, the maxillary teeth were more buccally inclined and
repeated measurements done by these observers were the mandibular teeth were more lingually inclined on the
used to calculate the intraclass correlation coefficient deviated sides than on the nondeviated sides (P \0.001;
(ICC) for intraobserver reliability, and their first and sec- Table III). Therefore, the buccolingual inclination values
ond measurements were compared for interobserver reli- for both sides were combined in groups I and S, and
ability. Paired t tests were used to examine the group AS was further divided into deviated sides (group
differences in inclination between the deviated sides D) and nondeviated sides (group ND) for subsequent
and nondeviated sides in each group. One-way analysis group comparisons.
of variance (ANOVA) and post hoc Bonferroni tests were In all groups, the buccolingual inclinations from the
used to compare the buccolingual inclination of the pos- first premolars to the second molars increased in the
terior teeth between Group I, S, deviated side of AS and maxilla and decreased in the mandible, indicating pro-
non-deviated side of AS. In groups I and S, linear regres- gressive torque. The maxillary teeth showed the most
sion analysis was performed to detect the impact of the buccal inclination in group D, followed by those in
sagittal skeletal discrepancy (ANB angle) on the bucco- groups S and I (P \0.05). The mandibular teeth showed
lingual inclination of the posterior teeth. In groups S the most lingual inclination in group D (P \0.05), and
and AS, linear regression analysis was carried out to groups S and I showed no significant difference in incli-
detect the influence of the transverse skeletal nation except for the second molar: group S had the

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Ahn et al 151

Fig 1. Landmarks and reference planes on a 3D image (N, Nasion; Or, orbitale; Po, porion; Me, men-
ton; R, right).

Fig 2. Method used to measure buccolingual inclination of the maxillary teeth: A, ensure that the axial
plane is oriented as the Frankfort horizontal plane; B, locate the molar in the axial view; C, in the sagittal
view, position the line to obtain the long-axis plane; D and E, in the long-axis plane, the horizontal refer-
ence line shown is parallel to the Frankfort horizontal plane. Measure the inclination between the long
axis of the tooth and the reference line (FH plane): D, premolar; E, molar.

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152 Ahn et al

Fig 3. Method to measure the buccolingual inclination of mandibular teeth: A, locate the molar in the
axial view; B, in the sagittal view, position the line to obtain the long-axis plane; C and D, in the long-axis
plane, measure the inclination between the long axis of the tooth and the reference line that is tangent to
the inferior border of the mandible: C, average premolar; D, average molar.

most lingual inclination. Interestingly, buccolingual reported yet. This study demonstrated that sagittal
inclination in group ND was not significantly different skeletal discrepancy mainly affects the buccolingual
from that in group I for any posterior teeth (P .0.05) inclination of the maxillary teeth. Skeletal Class III
except for the mandibular first molars (Table IV). patients showed more buccally inclined maxillary
Linear regression analysis showed that the ANB angle posterior teeth than did Class I patients, and this was
was negatively correlated with the inclination of the negatively correlated with ANB angle, indicating that a
maxillary teeth and positively correlated with that of sagittal skeletal discrepancy is an important cause of a
the mandibular second molars (P \0.05; Table V). Me transverse discrepancy. It seems that mandibular
deviation was positively correlated with the maxilla in posterior teeth are more resistant to dental
group D and the mandible in group ND, and was nega- compensation caused by a sagittal skeletal discrepancy.
tively correlated with the maxilla in group ND and the The reason that only the second molars showed greater
mandible in group D (P \0.05; Table VI). lingual inclinations in skeletal Class III patients is not
clear. Compensation by the maxillary molars may not be
DISCUSSION enough to establish an adequate occlusion, possibly due
This study demonstrates that transverse dental to the divergent morphology of the posterior mandible.
compensation is closely related to both sagittal and trans- Lingually inclined mandibular second molars are
verse skeletal discrepancies. Although previous researchers frequently observed in presurgical orthodontic patients,
have noted that transverse dental compensation depends and a strategic approach is necessary to upright these
on sagittal skeletal discrepancy,25,26 the relationship teeth from the start of treatment.
between the buccolingual inclination of the posterior Interestingly, in this study, the buccolingual inclina-
teeth and the sagittal skeletal discrepancy has not been tions progressively increased from the first premolars to

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Ahn et al 153

Fig 4. Representative CBCT images of a patient in group I at long-axis planes: A, maxillary first pre-
molar; B, maxillary second premolar; C, maxillary first molar; D, maxillary second molar; E, mandibular
first premolar; F, mandibular second premolar; G, mandibular first molar; H, mandibular second molar.

Table III. Comparison of the buccolingual inclinations between the deviated and nondeviated sides in each group
Skeletal Class I (n 5 25) Skeletal Class III, symmetry (n 5 30) Skeletal Class III, asymmetry (n 5 33)

Deviated side Nondeviated side P Deviated side Nondeviated side P Deviated side Nondeviated side
(mean 6 SD) (mean 6 SD) value (mean 6 SD) (mean 6 SD) value (mean 6 SD) (mean 6 SD) P value
Inclination of maxillary teeth (
)
4 88.4 6 5.18 86.7 6 4.77 0.069 90.7 6 6.51 90.8 6 4.94 0.953 94.2 6 5.60 87.0 6 5.57 \0.001*
5 91.0 6 4.44 90.5 6 4.71 0.638 94.1 6 5.90 95.0 6 5.72 0.075 99.3 6 5.28 89.6 6 5.29 \0.001*
6 93.6 6 4.91 91.3 6 4.62 0.053 97.0 6 4.21 97.4 6 3.75 0.450 101.0 6 4.87 90.4 6 6.04 \0.001*
7 99.8 6 4.11 97.9 6 5.60 0.093 102.4 6 5.49 103.3 6 5.74 0.308 109.3 6 7.01 100.3 6 8.74 \0.001*
Inclination of mandibular teeth (
)
4 90.2 6 4.09 91.8 6 6.43 0.176 88.7 6 4.90 88.2 6 4.02 0.655 81.9 6 6.76 90.5 6 3.51 \0.001*
5 84.0 6 5.59 83.3 6 5.26 0.639 82.4 6 6.01 83.1 6 4.40 0.540 76.6 6 7.56 85.2 6 4.67 \0.001*
6 76.7 6 6.24 78.8 6 4.87 0.135 77.5 6 4.46 78.4 6 4.44 0.363 73.2 6 6.19 82.7 6 6.10 \0.001*
7 76.9 6 5.75 77.1 6 6.20 0.855 71.4 6 7.32 72.2 6 6.64 0.560 65.8 6 8.01 76.9 6 7.76 \0.001*
Paired t test was conducted to compare the values of the deviated and nondeviated sides in each group.
4, First premolar; 5, second premolar; 6, first molar; 7, second molar.
*P \0.001.

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154 Ahn et al

Table IV. Comparison of the buccolingual inclinations among the groups

Skeletal Class III,
asymmetry

Skeletal Class III, Deviated Nondeviated

symmetry side side
Skeletal Class I (mean 6 SD) (mean 6 SD) (mean 6 SD) (mean 6 SD) P value Multiple comparison
Inclination of maxillary teeth (
)
4 87.6 6 5.01 90.7 6 5.73 94.2 6 5.60 87.0 6 5.57 \0.001z ND 5 I
I \ S*
S \ D*
5 90.7 6 4.54 94.8 6 5.08 99.3 6 5.28 89.6 6 5.29 \0.001z ND 5 I
I \ Sz
S \ Dy
Premolar 89.1 6 5.01 92.8 6 6.04 96.7 6 5.99 88.3 6 5.55 \0.001z ND5I
I \ Sz
S \ Dz
6 92.5 6 4.85 97.2 6 3.96 101.0 6 4.87 90.4 6 6.04 \0.001z ND 5 I
I \ Sz
S \ Dy
7 98.9 6 4.52 102.9 6 5.59 109.2 6 7.01 100.3 6 8.74 \0.001z I 5 ND, ND 5 S
I \ Sy
S \ Dz
Molar 95.7 6 5.85 100.0 6 5.60 105.1 6 7.30 95.3 6 8.98 \0.001z ND5I
I \ Sz
S \ Dz
Inclination of mandibular teeth (
)
4 91.0 6 5.40 88.4 6 4.45 81.9 6 6.76 90.5 6 3.51 \0.001z D \ Sz
S 5 ND 5 I
5 83.6 6 5.38 82.7 6 5.24 76.6 6 7.56 85.2 6 4.67 \0.001z D \ Sz
S 5 I 5 ND
Premolar 87.3 6 65.2 85.6 6 5.63 79.3 6 7.60 87.9 6 4.89 \0.001z D \ Sz
S 5 I 5 ND
6 77.7 6 5.64 78.0 6 4.43 73.2 6 6.19 82.7 6 6.10 \0.001z D \ Iz
I5S
S \ NDy
7 77.0 6 5.92 71.8 6 6.94 65.8 6 8.01 76.9 6 7.76 \0.001z D \ Sy
S \ NDy
ND 5 I
Molar 77.3 6 5.77 74.9 6 6.56 69.5 6 8.02 79.8 6 75.2 \0.001z D \ Sz
S 5 I 5 ND
Data were analyzed by 1-way ANOVA and multiple comparison with the Bonferroni test at significance levels of *P \0.05; yP \0.01; and
z
P \0.001.
I, Skeletal Class I; S, skeletal Class III, symmetry; D, deviated side of skeletal Class III, asymmetry; ND, nondeviated side of skeletal Class III, asym-
metry; 4, first premolar; 5, second premolar; 6, first molar; 7, second molar.

the second molars in the maxilla and decreased in the With regard to the transverse skeletal discrepancy, we
mandible. These results partially agree with the concept found that the posterior teeth on the deviated sides
of ideal occlusion described by Andrews,1 who reported showed more transverse dental compensation, whereas
that the lingual inclination from the premolars through that on the nondeviated sides did not differ significantly
the molars was constant in the maxillary teeth, although from the skeletal Class I control group. This was probably
slightly more pronounced in the molars, and progressively due to the combined effects of sagittal and transverse
increased in the mandibular teeth. The more-pronounced skeletal discrepancy. Although these effects were in the
lingual inclination of the maxillary molars seen in this same direction on the deviated sides, resulting in more
study might be due to the different tools used to assess dental compensation, they were in the opposite direction
the inclination of the posterior teeth. Whereas Andrews on the nondeviated sides, resulting in no apparent
evaluated inclination from the buccal crown contour on dental compensation. Regression analysis showed a sig-
dental casts, we used CBCT images showing not only nificant correlation between Me deviation and inclina-
crown contours but also root morphology. tion not only on the deviated sides, but also on the

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Ahn et al 155

facial asymmetry. Whereas little effort may be required

Table V. Linear regression analyses and correlation
in patients with transverse dental decompensation on
coefficients between ANB angles and buccolingual in-
the nondeviated side, a strategic approach is needed
clinations of the posterior teeth in groups I and S
for active dental decompensation on the deviated side,
Correlation coefficient P value even producing a posterior crossbite.
Maxillary teeth This study had some limitations. Although the
4 0.177 0.064 method used to measure buccolingual inclination was
5 0.363 \0.001y
deemed reliable by Shewinvanakitkul et al,27 they com-
6 0.399 \0.001y
7 0.236 0.013* mented that the approach to each tooth was not perpen-
Mandibular teeth dicular to its buccolingual plane. In our study, the
4 0.025 0.797 sagittal slice of CBCT was obtained parallel to the
5 0.101 0.294 midsagittal plane, not parallel to the mesiodistal surface
6 0.026 0.788
of each tooth. If the sagittal CBCT slice was obtained
7 0.396 \0.001y
parallel to the mesiodistal surface of the tooth, the infe-
4, First premolar; 5, second premolar; 6, first molar; 7, second molar.
rior border of the mandible would not be seen clearly.
*P \0.05; yP \0.001.
Since the buccolingual inclination and the mesiodistal
angulation of the tooth are combined in 3 dimensions,28
Table VI. Linear regression analyses and correlation Tong et al13 introduced a root vector analysis program
coefficients between Me deviation and buccolingual that measures angulation and inclination in 3 dimen-
inclinations of the posterior teeth in groups S and AS sions, but this method cannot be used in patients with
Correlation coefficient P value malocclusion, especially those with asymmetry. Second,
Maxillary teeth we did not divide the sample according to the presence
4 or absence of posterior crossbite; however, approxi-
D 0.315 0.012* mately half of the patients in group AS had a posterior
ND 0.336 0.007y
crossbite on the deviated side that may have influenced
5
D 0.467 \0.001z the degree of dental compensation. Future studies that
ND 0.455 \0.001z consider this aspect in larger sample sizes are needed.
6
D 0.487 \0.001z CONCLUSIONS
ND 0.543 \0.001z
7 In this study, the buccolingual inclinations of all pos-
D 0.54 \0.001z terior teeth measured using CBCT images were investi-
ND 0.133 0.299 gated in skeletal Class III patients with and without
Mandibular teeth
asymmetry and compared with those in a skeletal Class
4
D 0.578 \0.001z I control group. Skeletal Class III patients showed greater
ND 0.384 0.002y buccal inclinations of the maxillary posterior teeth and
5 lingual inclinations of the mandibular second molars
D 0.479 \0.001z than did skeletal Class I patients, and these were corre-
ND 0.304 0.016*
lated with the degree of sagittal skeletal discrepancy.
6
D 0.511 \0.001z The deviated sides in skeletal Class III patients with
ND 0.167 0.192 asymmetry showed the greatest transverse dental
7 compensation, which was correlated with the amount
D 0.516 \0.001z of Me deviation, whereas the nondeviated sides showed
ND 0.29 0.021*
no significant transverse dental compensation. These re-
4, First premolar; 5, second premolar; 6, first molar; 7, sults will be helpful in understanding the mechanisms of
second molar; D, deviated side; ND, nondeviated side.
transverse dental compensation and planning treatment
*P \0.05; yP \0.01; zP \0.001.
for skeletal Class III patients with transverse discrepancy.

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January 2017  Vol 151  Issue 1 American Journal of Orthodontics and Dentofacial Orthopedics