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The effectiveness of clear aligners in levelling the curve of Spee and related maxillofacial factors in patients with a deep overbite Cover

The effectiveness of clear aligners in levelling the curve of Spee and related maxillofacial factors in patients with a deep overbite

Australasian Orthodontic Journal
Volume 40 (2024): Issue 1 (January 2024)
By: ,  ,  ,  ,  ,   and    
Open Access
|Jul 2024
Figures & tables

Figures & Tables

Figure 1.

Measurements made using the digital dental model. (A) Depth of COS. The occlusal plane is established in the mandibular dental arch, followed by measurement of the perpendicular distances from the occlusal plane to the buccal cusp tip of each lateral tooth. (B) Crowding analysis. Left, the sum of the tooth widths of the mandible: proximal and distal width of each tooth (T1). Right, the total recorded arch perimeter: the length of the mandibular dental arch (T1). COS, curve of Spee.

Figure 2.

Details of the cephalometric and panoramic radiograph measurements. (A) Measurements made using the lateral cephalogram. (B) Measurement of incisor parallelism.

Table I.

Description of cephalometric description

Cephalometric measurementDescription
MP-FH (°)The angle between Frankfort horizontal plane (Or, Po) and mandibular plane (Me, Go)
RP-MP (°)The angle between ramal plane (Ar, Go) and mandibular plane (Me, Go)
IMPA (°)The angle between mandibular incisors (LIA, LI) and mandibular plane (Me, Go)
Posterior/anterior face height (P/A) (%)The ratio between posterior face height (S-Go) and anterior face height (N-Me)
Panoramic radiograph measurement
Incisors’ parallelism (%)The ratio of length between the midpoint of lateral incisor edges and the length between the lateral incisor root tips

[i] COS, The curve of Spee; D, Depth of COS; E, leveling efficiency;

[ii] P, parallelism of the mandibular incisors; SD, standard deviation;

[iii] SEM, standard error; pretreatment.

Table II.

The intraclass correlation coefficient

95% confidence interval
Intraclass correlationLower boundUpper bound
COS depth (T1)0.8710.7960.923
COS depth (T2)0.8010.6680.886
COS depth (T3)0.8640.7860.920
MP-FH (T1)0.9770.9620.987
PP-MP (T1)0.9500.9170.972
RP-MP (T1)0.9790.9650.988
IMPA (T1)0.9380.9000.964
P/A (T1)0.9530.9210.973
C (T1)0.9400.9020.965
P (T1)0.9150.8630.950
Table III.

Summary statistics for the variables (n =42)

MeanSEMSD
MP-FH (°)28.1230.9496.153
RP-MP (°)121.7640.8305.382
IMPA (°)93.2191.0987.117
P/A (%)0.6340.0090.059
Crowding(mm)1.2480.2951.911
D(T1) (mm)2.5130.1010.656
D(T2) (mm)1.6430.0660.432
D(T3) (mm)1.2790.0700.456
P (%)1.0570.0400.259
Achieved leveling value0.9010.0700.455
Predicted leveling value1.2510.0840.542
Table IV.

Stepwise multiple regression analysis for the leveling efficiency

Dependent variableStatistically significantindependent variablesBSEM BP-valueTR2 change
EMP-FH (T1)0.0080.3020.050*1.9750.025
D (T1)0.1200.4250.006**2.9230.531
P (T1)-0.254-0.3730.011*-2.6680.280
IMPA (T1)0.0050.6230.007**2.9230.049

* P = 0.05,

** P = 0.01,

*** P = 0.001,

**** P = 0.0001.

DOI: https://doi.org/10.2478/aoj-2024-0015 | Journal eISSN: 2207-7480 | Journal ISSN: 2207-7472
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Language: English
Page range: 169 - 177
Submitted on: Dec 1, 2023
Accepted on: May 1, 2024
Published on: Jul 11, 2024
Published by: Australian Society of Orthodontists Inc.
In partnership with: Paradigm Publishing Services
Publication frequency: 1 issue per year
Related subjects:
Medicine,
Basic medical science,
Basic medical science, other

© 2024 Li Zhang, Beiwen Gong, Xianju Xie, Li Cao, Yingzhi Gu, Yaxi Sun, Yuxing Bai, published by Australian Society of Orthodontists Inc.
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 40 (2024): Issue 1 (January 2024)
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