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J Bagh College Dentistry
Vol. 23(2), 2011
The dentoalveolar compensation
The dentoalveolar compensation in different skeletal
patterns of Iraqi adults
Dr. Shaymaa Sh. Taha, B.D.S., M.Sc. (1)
ABSTRACT
Background: For different skeletal discrepancies, the maxillary and mandibular incisors were inclined in normal incisor
relationships as a result of dentoalveolar compensatory mechanism. The aims of this study were to compare the
dentoalveolar compensation among skeletal class I, skeletal class II, and skeletal class III jaw patterns, and to
determine the gender difference in each class.
Materials and Methods: The patients’ history, clinical examination and Lateral cephalometric radiographs were
taken for 85 adult subjects. According to ANB angle the sample classified into: 30 adult subjects skeletal class I
(control samples), 30 adult subjects skeletal class II and 25 adult subjects skeletal class III (study samples), the
cephalometric radiographs are analyzed by using AutoCAD 2008 program.
Results and Conclusion: Sagittal jaw parameters show classes difference (by using ANOVA and LSD test) among
different skeletal classes, vertical and dental parameters show gender and classes differences, while linear
measurements show gender difference (by using independent t-test). Dentoalveolar compensation is affected by
lower incisors in skeletal class II and by upper and lower incisors in skeletal class III.
Key words: Dentoalveolar compensation, different skeletal patterns. (J Bagh Coll Dentistry 2011;23(139-145).
INTRODUCTION
Facial esthetics is an important motivating
factor for many patients seeking orthodontic
treatment1-3.Differing methods for evaluating
facial profiles have been proposed in the
orthodontic literature including traditional
cephalometrics and repose soft tissue analysis
.Traditional cephalometrics uses internal osseous
land marks to define points, lines, and/or planes,
which in turn are used to quantify anteroposterior
(AP) jaw and incisor positions4.
During facial growth and development,
normal occlusion can be attained and maintained
despite some variation in facial pattern, primarily
as a result of dental compensation5-10. For existing
sagittal
jaw
discrepancies,
compensatory
inclination of the maxillary and mandibular
incisors results in normal incisor relationships 57,9-10
. The cant of the occlusal plane adjusts
sagittal relationships between the maxillary and
mandibular dental arches8. Some authors have
suggested that malocclusion results from
insufficient dentoalveolar compensation for
variations in facial patterns5,7,9.
The position of upper and lower incisors
relative to each other and to their supporting
bones is an important feature in a case analysis,
post treatment stability, and harmony and balance
of the facial profile. Since the introduction of
cephalometrics, incisor position in the sagittal
plane has become a valuable tool in assessing a
malocclusion11.
(1)Assistant lecturer /Department of Orthodontics, College of
Dentistry, University of Baghdad
Orthodontics, Pedodontics and Preventive Dentistry139
The aims of this study were to compare the
dentoalveolar compensation among different
skeletal patterns, and to determine the gender
difference in each class.
MATERIALS AND METHODS
Sample
Pretreatment lateral cephalograms of 85
untreated Subjects, who were selected from
patients attended the Orthodontic Clinic in the
Orthodontic Department at the College of
Dentistry, University of Baghdad. According to
ANB angle, the sample were consisted of 3
groups: 30 adults skeletal class I (15 males and 15
females) in which 2˚ <ANB< 4˚, 30 adults
skeletal class II (15 males and 15 females) in
which ANB> 4˚ and 25 adults skeletal class III
(11 males and 14 females) in which ANB< 2˚,
selected from the patients attended to the
Orthodontic department at the College of
Dentistry, University of Baghdad meeting the
following criteria:
1. All the subjects were Iraqi Arab in origin,
aged 18-25 years old with no history of
facial trauma.
2. No history of previous orthodontic
treatment.
3. Full permanent dentition regardless the
third molar.
4. The incisors had not been crowned or
severely rotated.
5. Clinically (palpation method of Foster)
and cephalometrically (according to ANB
angle) skeletal class I, II, and III.
J Bagh College Dentistry
Vol. 23(2), 2011
Method
The patients’ history, clinical examination
and cephalometric radiographs were taken for 85
adult subjects. The cephalometric radiographs
were taken by standard method by using
Planmeca machine. The radiographs were taken
with Frankfort plane horizontal, the teeth in
centric occlusion, and the patients in rest head
position. Every lateral cephalometric radiograph
was analyzed by AutoCAD program 2008 to
calculate the cephalometric measurements. Once
the picture is imported to the AutoCAD program,
it will appear in the master sheet on which the
points and planes were determined, and then the
measurements were obtained. The angles were
measured directly as they were not affected by
magnification while the linear measurement was
divided by scale for each picture to overcome the
magnification.
Cephalometric landmarks (Figure 1)
The following points were used in this study
and defined according to Rakosi 12: Sella (S),
Nasion (N), Anterior nasal spine (ANS), Posterior
nasal spine (PNS), Articulare (Ar), Gonion (Go),
Menton (Me), Point A, Point B, Incisor superius
(Is), Incisor inferius (Ii), Frontal and Distal points
of occlusal plane (Fpop, Dpop),
Apicale
¯1¯(Ap1), and Apicale 1 (Ap2).
Reference lines (Figure 2):
1. Sella nasion (SN)12: Anteroposterior
extent of anterior cranial base.
2. Occlusal plane (OP)13: located as the
bisected occlusal plane, extend from
frontal point of occlusal plane (Fp Op)to
the dorsal point of occlusal plane(Dp op)
3. A-B13: Formed by a line joining points A
and B.
4. Palatal plane (PP)12: formed by a line
joining points ANS and PNS.
5. Mandibular plane (MP) 12: formed by a
line joining points Go and menton Me.
6. N-A plane14: formed by a line joining
points A and N.
7. N-B plane14: formed by a line joining
points B and N.
Angular measurements (Figure2):
I. Sagittal jaw parameters
1. SN-AB Angle: Angle between SN line
and AB line13.
2. ANB Angle: Difference between SNA
and SNB12.
II. Vertical jaw parameters
The dentoalveolar compensation
3. SN-MP: This angle gives the inclination
of the mandible to the anterior cranial
base12.
4. SN-PP: Angle between SN line and
palatal plane12.
5. PP-MP: Angle between palatal plane and
mandibular plane12.
III. Dental parameters
6. SN-U1: Angle between SN line and
upper incisor axis12,13
7. SN-L1: Angle between SN line and
lower incisor axis12,13.
8. SN-OP: Angle between SN line and
occlusal plane13.
9. U1-PP: Angle between upper incisor axis
and palatal plane, anteriorly12.
10. L1-MP: Angle between lower incisor
axis and mandibular plane, posteriorly12.
11. U1-NA: Angle between upper incisor
axis and NA plane14.
12. L1-NB: Angle between lower incisor
axis and NB plane14.
13. Inter-incisal Angle (U1-L1): Angle
between upper incisor axis and lower
incisor axis posteriorly12.
Linear measurements (Figure 2):
1. Maxillary length12: The horizontal
distance of palatal plane (Pal) between
ANS point and PNS point.
2. Upper anterior facial height (UAFH)
12
: The vertical distance between N point
and ANS point.
Statistical analysis
Data were statistically analyzed by a
software computer program SPSS, version 15 to
obtain descriptive statistics (means, standard
deviation, and standard error), and inferential
statistics: independent t-test, one way analysis of
variance (ANOVA), and LSD test between the
three skeletal classes.
RESULTS AND DISCUSSION
Tables (1) and (2)show the descriptive
statistics, gender difference by using independent
t-test, and classes difference by using one way
analysis of variance(ANOVA) for skeletal jaw
and dental parameters respectively. Tables (3) and
(4) show LSD post hoc test for males and females
respectively, are used to determine any significant
difference between three skeletal classes.
1. Angular measurements:
A. Sagittal jaw parameters: As shown in
Table (1) the SN-AB˚ and ANB˚ angles have no
Orthodontics, Pedodontics and Preventive Dentistry140
J Bagh College Dentistry
Vol. 23(2), 2011
significant gender difference in all three skeletal
classes. As shown in table (1) the SN-AB ˚and
ANB˚ angles are very high significant difference
among all three skeletal classes. As shown in table
(3) LSD test for males shows that SN-AB˚ is very
high significant difference between skeletal class I
and II, and between skeletal class II and III. Table
(4) LSD for females shows that the SN-AB˚ has a
very high significant difference among all three
skeletal classes. Also LSD for males and females
show that ANB˚ has a very high significant
difference among all three skeletal classes. The
mean values of SN-AB˚ for males and females in
skeletal class II are less than that of skeletal class
I and III. These results show the differences in the
sagittal jaw relationships which might be due to
mandibular rotation, so backward rotation is
carrying point B away from point A, while
forward rotation is bringing point B
forward15.These results show no mechanism
acting to reduce the sagittal jaw discrepancy in
this sample and this agrees with Bibby 10.
B. Vertical jaw parameters: As shown in
table (1), the mean values of each of SN-MP˚ and
PP-MP˚ angles in skeletal class I and II are higher
in females than males.SN-MP˚ has a significant
gender difference in skeletal class II and very
highly significant gender difference in skeletal
class I. While PP-MP˚ has a significant gender
difference in skeletal class I, this disagrees with
Hassan16, this is may be due to difference in
sample size or selection while PP-MP˚ shows no
significant classes difference. The SN-MP˚ gives
the inclination of the mandible to the anterior
cranial base. Schudy had introduced the concept
of posterior and anterior inclination, if the angle is
greater than 32˚the inclination is posterior, but if
it’s less than32˚the inclination is anterior12.So
females in skeletal class I and II have posterior
inclination of the mandible to the anterior cranial
base. SN-MP˚ for males shows significant classes
difference, table (3) LSD for males shows that
there is significant classes difference between
skeletal class I and III, these results may be due to
dentoalveolar compensation for skeletal class III
jaw discrepancies which can be expressed as
counter clockwise rotational change in the entire
dentoalveolar structure17.SN-PP shows nonsignificant gender and classes differences.
C. Dental parameters: Table (2) U1-PP˚, U1NA˚, and L1-MP˚ angles show no gender
difference, while SN-U1˚ (skeletal class I), SNOP˚ (skeletal class II), and U1-L1˚ (skeletal class
III) angles show significant gender difference.
SN-L1˚, U1-L1˚, and L1-NB˚ (skeletal class II)
Orthodontics, Pedodontics and Preventive Dentistry141
The dentoalveolar compensation
and SN-OP ˚ (skeletal class I) angles show very
highly significant gender difference. The mean
values of SN-U1˚,U1-PP˚,L1-MP˚, andU1-NA˚
angles in skeletal class I are statistically higher in
males for each angle, while in skeletal class II and
class III these angles are statistically higher in
females for each angle. The mean values of SNL1˚ (all skeletal classes) and U1-L1˚ (skeletal
class II and class III) angles are statistically higher
in males for each angle. U1-L1˚ (skeletal class I)
and L1-NB˚ (all skeletal classes) angles are
statistically higher in females for each angle. As
shown in table (2) SN-U1˚,U1-PP˚,U1-L1˚, and
L1-NB˚ angles for females show very high
significant classes difference for each angle, while
SN-L1˚,L1-MP˚,and U1-NA˚angles for males
show significant classes difference for each angle,
while the same angles for females show very high
significant classes differences. The mean values
of each of SN-OP˚ and SN-MP˚ angles (in
skeletal class I and class II) are statistically higher
in females, As mentioned previously, females in
skeletal class I and II have posterior inclination of
the mandible to the anterior cranial base, so their
SN-OP˚ become steeper in skeletal class I and
class II, due to that the mandibular and occlusal
planes may rotate in conjunction with each other
or rotate separately8 .SN-OP˚ shows nosignificant classes difference.
The interincisal angle is an important
indicator for stable orthodontic treatment, and is
greatly
influenced
by
dentoalveolar
compensation18, as shown in table 1 and 3, the
mean value of U1-L1˚ in skeletal class II (due to
proclination of U1) is smaller than that in skeletal
class I and class III, while skeletal class III (due to
U1proclination and L1retroclination) U1-L1˚is
more than class I and class II.
Tables (1,2,3 and 4) show that dentoalveolar
compensation can be seen in lower incisor only
(by proclination tendency) for skeletal class II and
this disagrees with Bibby10,and in upper
incisor(by proclination tendency) and lower
incisor (by retroclination tendency) for skeletal
class III and this agrees with Bibby10and
Ishikawa13.Proclination of upper incisors in
skeletal class II cases is an unexpected finding ,
which can be explained by insufficient maxillary
dentoalveolar compensation or due to soft tissue
factor (lower lip acting behind upper incisors),this
finding shows that the skeletal class II samples are
dentally class II division 1. The present results
show that there are dentoalveolar changes in the
axial inclination of the maxillary and mandibular
incisors in different skeletal patterns. Some
investigators have suggested that malocclusions
J Bagh College Dentistry
Vol. 23(2), 2011
result
from
insufficient
dentoalveolar
compensation for variation in facial patterns7,13.
2-Linear measurements: As shown in table
(1) the mean values of each of maxillary length
and UAFH linear measurements are statistically
larger in males than that of females, this gender
difference may be due to19,20:
• The smaller and smoother boney and
alveolar process in females.
• The average weakness of musculature in
females that plays an important role in
facial breadth measurements, width, and
height of the dental arch.
REFERENCES
1.
Dorsey J, Korabik K. Social and psychological
motivations for orthodontic treatment. Am J Ortho 1977;
72:460-7.
2.
Kilpelanien P, Phillips C, Tulloch JFC. Anterior
tooth position and motivation for early treatment. Angle
Ortho 1993; 63:171-4.
3.
McKiernan EXF, McKiernan F, Jones ML.
Psychological profile and motives of adults seeking
orthodontic treatment. Int J Adult Orthod Orthognath Surg
1992; 7:1887-98.
4.
Will A.A. AP relationship of the maxillary
central incisor to the forehead in adult white females.
Angle Orthod 2008; 78: 662-9.
5.
Proffit WR. Contemporary orthodontics.3rd
edition. St. Louis: Mosby, 2000.
6.
Björk, A. Sutural growth of the upper face
studied by the implant method. Acta Odontol Scand 1966;
24:109-27
7.
Solow B. The pattern of craniofacial
associations: A morphological correlation and factor
analysis study on young male adults. Acta Odontol Scand
1966; 24: Supp 46.
8.
Enlow DH, Kuroda T, Lewis AB. Intrinsic
craniofacial compensations. Angle Orthod 1971; 41:27185.
The dentoalveolar compensation
9.
Björk A. Facial development and tooth eruption:
An implant study at the age of puberty. Am J Orthod
1972; 62:339-82.
10.
Bibby RE. Incisor relationships in different
skeletofacial patterns. Angle Orthod 1980; 50: 41-4.
11.
Ellis EE, McNamara J. A Cephalometric
evaluation of incisor position. Angle Orthod 1986; 56:
324-44.
12.
Rakosi T. An atlas and manual of cephalometric
radiography. 2nd ed. London: Wolfe medical publications
Ltd.; 1982.
13.
Ishikawa H, Nakamura S, Iwasaki H, Kitazawa
S, Tsukada H, Chu S. Dentoalveolar compensation in
negative overjet cases. Angle Orthod 2000; 70(2):145-8.
14.
Ceylan I, Baydas B, Bölukabasi B. Longitudinal
cephalometric changes in incisor position, overjet, and
overbite between 10 and 14 years of age. Angle Orthod
2002; 72(3): 246-50.
15.
Al-Chalabi H. Skeletodental measurements in
Iraqi patients sample with class II division 1 malocclusion
and different vertical discrepancies. Master thesis,
Department of Orthodontics, University of Baghdad,
2009.
16.
Hassan MN. Dentoalveolar compensation in
relation to mild skeletal discrepancies. Master thesis,
Department of Orthodontics, University of Baghdad,
2007.
17.
Ishikawa H, Nakamura S, Iwasaki H, Kitazawa
S, Tsukada H, Sato Y. Dentoalveolar compensation related
to variations in sagittal jaw relationships. Angle Orthod
1999; 69(6): 534-8.
18.
Al-Hashimi H, Al-Bustani A, Abdulla N.
Dentoalveolar compensation in skeletal class
III
malocclusion and the treatment requirements. Iraqi Orthod
2007; 3(1): 40-2.
19.
Younes SA. Maxillary arch dimensions in Saudi
and Egyptian population sample Am J Orthod Dentofac
Orthop 1984; 85:83-7.
20.
Al-Hadithy SF. Dental arch dimensions and
forms in Sulaimania Kurdish population sample aged 1624 years with Class I normal occlusion. Master thesis,
Department of Orthodontics, University of Baghdad,
2005.
Figure 1: Cephalometric landmarks Figure 2: Cephalometric analysis:
identification (cephalometric points) cephalometric planes, angular and
Orthodontics, Pedodontics and Preventive Dentistry142
J Bagh College Dentistry
Vol. 23(2), 2011
The dentoalveolar compensation
Table 1: Descriptive statistics, gender difference and classes’ difference for skeletal jaw
parameters (sagittal and vertical)
Descriptive statistics
Classes difference
Variables
Gender
Class I
Class II
Class III
Mean
S.D
S.E
Mean
S.D
S.E
Mean
S.D
S.E
F-test
p-value
Male
76.47
3.48
0.90
70.73
4.01
1.03
79.30
3.47
1.10
18.04
0.000 ***
Female
74.67
2.02
0.52
68.80
3.34
0.86
79.71
3.83
1.02
43.89
0.000 ***
SN-ABº
t-test
1.73
1.43
-0.27
p-value
0.09 (NS)
0.16(NS)
0.79(NS)
Male
2.73
1.10
0.28
5.53
1.13
0.29
-0.10
1.29
0.41
72.11
0.000 ***
Female
2.87
1.06
0.27
6.33
1.45
0.37
-0.14
1.46
0.39
85.87
0.000 ***
ANBº
t-test
-0.34
-1.69
0.07
p-value
0.74(NS)
0.10(NS)
0.94(NS)
Male
28.87
5.57
1.44
31.73
4.74
1.22
34.50
6.11
1.93
3.31
0.05 *
Female
34.20
3.76
0.97
35.20
4.26
1.10
34.43
5.77
1.54
0.19
0.83(NS)
SN-MPº
t-test
-3.07
-2.11
0.03
p-value
0.000 ***
0.04 *
0.98(NS)
Male
7.47
3.68
0.95
8.40
2.16
0.56
8.80
2.70
0.85
0.70
0.50(NS)
Female
9.33
3.54
0.91
8.27
3.01
0.78
10.14
3.03
0.81
1.25
0.30(NS)
SN-PPº
t-test
-1.42
0.14
-1.12
p-value
0.17(NS)
0.89(NS)
0.28(NS)
Male
21.27
4.74
1.22
23.27
4.96
1.28
25.60
4.77
1.51
2.43
0.10(NS)
Female
24.87
4.49
1.16
26.93
5.28
1.36
24.14
5.83
1.56
1.13
0.33(NS)
PP-MPº
ANS-PNS
(mm)
UAFH
(mm)
t-test
-2.14
-1.96
0.65
p-value
0.04 *
0.06(NS)
0.52(NS)
Male
53.61
4.09
1.06
53.91
2.91
0.75
53.07
3.92
1.24
0.16
0.85(NS)
Female
48.93
4.10
1.06
50.94
3.07
0.79
49.47
3.16
0.84
1.34
0.27(NS)
t-test
3.13
2.72
2.49
p-value
0.000 ***
0.01 **
0.02 *
Male
52.22
2.72
0.70
52.78
2.77
0.72
53.53
2.55
0.81
0.71
0.50(NS)
Female
50.78
2.45
0.63
50.55
2.85
0.74
50.22
2.58
0.69
0.16
0.85(NS)
t-test
1.53
2.17
3.11
p-value
0.14 (NS)
0.04 *
0.01 **
Orthodontics, Pedodontics and Preventive Dentistry143
J Bagh College Dentistry
Vol. 23(2), 2011
The dentoalveolar compensation
Table 2: Descriptive statistics, gender difference and classes’ difference for dental parameters
Descriptive statistics
Classes difference
Variables
Gender
Class I
Class II
Class III
Mean
S.D
S.E
Mean
S.D
S.E
Mean
S.D
S.E
F-test
p-value
Male
105.60
5.19
1.34
104.60
5.34
1.38
106.30
5.12
1.62
0.33
0.72 (NS)
Female
101. 27
5.47
1.41
107. 27
4.08
1.05
108.86
5.26
1.41
9.55
0.000 ***
SN-U1º
t-test
2.22
-1.54
-1.19
p-value
0.03 *
0.14(NS)
0.25(NS)
Male
53.60
5.03
1.30
48.93
3.24
0.84
53.00
6.73
2.13
3.78
0.03 *
Female
50.27
4.40
1.14
41.87
4.69
1.21
50.07
4.14
1.11
17.45
0.000 ***
SN-L1º
t-test
1.93
4.80
1.32
p-value
0.06(NS)
0.000 ***
0.20(NS)
Male
11.33
3.89
1.00
13.20
3.43
0.88
14.80
3.99
1.26
2.65
0.08(NS)
Female
16.40
3.00
0.77
15.93
2.79
0.72
14.64
3.75
1.00
1.17
0.32(NS)
SN-OPº
t-test
- 4.00
-2.40
0.10
p-value
0.000 ***
0.02 *
0.92(NS)
Male
113.27
5.75
1.48
113.00
5.84
1.51
115.10
5.55
1.75
0.45
0.64(NS)
Female
110.53
4.07
1.05
115.47
4.03
1.04
118. 93
5.12
1.37
13.27
0.000 ***
U1-PPº
t-test
1.50
-1.35
-1.74
p-value
0.14(NS)
0.19(NS)
0.09(NS)
Male
97.53
5.14
1.33
99.20
5.58
1.44
92.70
7.36
2.33
3.74
0.03 *
Female
95.80
6.03
1.56
102.93
4.91
1.27
95.71
5.68
1.52
8.25
0.000 ***
L1-MPº
t-test
0.85
-1.95
-1.13
p-value
0.40(NS)
0.06(NS)
0.27(NS)
Male
127.80
8.25
2.13
124.33
7.37
1.90
126.80
8.74
2.76
0.73
0.49(NS)
Female
128.87
7.93
2.05
114.67
6.10
1.58
121.14
3.55
0.95
19.86
0.000 ***
U1-L1º
t-test
-0.36
3.91
2.20
p-value
0.72(NS)
0.000 ***
0.04 *
Male
22.40
4.97
1.28
20.27
5.74
1.48
26.90
5.38
1.70
4.62
0.02 *
Female
19.60
5.37
1.39
22.80
3.71
0.96
29.43
4.50
1.20
17.25
0.000 ***
U1-NAº
t-test
1.48
-1.44
-1.25
p-value
0.15(NS)
0.16(NS)
0.22(NS)
Male
27.07
5.32
1.37
29.73
4.17
1.08
26.30
5.56
1.76
1.74
0.19(NS)
Female
28.47
4.10
1.06
36.20
4.65
1.20
29.57
3.11
0.83
16.11
0.000 ***
L1-NBº
t-test
-0.81
-4.01
-1.84
p-value
0.43(NS)
0.000 ***
0.08(NS)
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J Bagh College Dentistry
Vol. 23(2), 2011
Table 3: LSD test for males
Variables Classes
5.73
0.000 ***
III
-2.83
0.07 (NS)
II III
-8.57
0.000 ***
II
4.67
0.01 **
III
0.60
0.77(NS)
II III
-4.07
0.05 *
II
-1.67
0.45(NS)
SN-ABº
I
SN-L1º
I
Variables Classes
SN-ABº
SN-U1º
SN-L1º
Mean
p-value
Difference
II
5.87
0.000 ***
III
-5.05
0.000 ***
II III
-10.91
0.000 ***
II
-6.00
0.000 ***
III
-7.59
0.000 ***
II III
-1.59
0.39(NS)
I
I
II
8.40
0.000 ***
III
0.20
0.91(NS)
II III
-8.20
0.000 ***
II
-4.93
0.000 ***
III
-8.40
0.000 ***
II III
-3.46
0.04 *
II
-7.13
0.000 ***
III
0.09
0.97(NS)
I
III
4.83
0.05 *
II III
6.50
0.01 **
II
-2.80
0.000 ***
III
2.83
0.000 ***
II III
5.63
0.000 ***
II
-2.87
0.16(NS)
III
-5.63
0.02 *
II III
-2.77
0.22(NS)
II III
7.22
0.000 ***
II
-3.47
0.000 ***
III
3.01
0.000 ***
II III
6.48
0.000 ***
I
II
14.20
0.000 ***
III
7.72
0.000 ***
II III
-6.48
0.01 **
II
-3.20
0.06(NS)
L1-MPº
I
ANBº
I
SN-MPº
II
2.13
0.28(NS)
III
-4.50
0.05 *
II III
-6.63
0.000 ***
I
U1-NAº
Table 4: LSD test for females
Mean
p-value
Difference
II
I
The dentoalveolar compensation
N.B. The following levels of significance are used:
• Non significant (NS): P>0.05
• Significant (*):0.05>P>0.01
• Highly significant (**):0.01>P>0.001
• Very highly significant (***): P<0.001
U1-PPº
L1-MPº
ANBº
I
I
I
U1-L1º
M
U1-NAº
L1-NBº
Orthodontics, Pedodontics and Preventive Dentistry145
I
III
-9.83
0.000 ***
II III
-6.63
0.000 ***
II
-7.73
0.000 ***
III
-1.10
0.46(NS)
II III
6.63
0.000 ***
I