|
Document Type |
: |
Thesis |
|
Document Title |
: |
Structural Predictors of Mandibular Growth: A Three-dimensional Study المتنبئات الھیكلیة في نمو الفك السفلي: دراسة ثلاثیة الأبعاد |
|
Subject |
: |
Faculty of Dentistry |
|
Document Language |
: |
Arabic |
|
Abstract |
: |
Objectives: The aim of this study is to evaluate the accuracy of the seven mandibular indicators suggested by Björk in predicting mandibular growth using three-dimensional cone beam computed tomography (CBCT), and to investigate the association between these indicators with mandibular divergence.
Materials: A total of 84 CBCT scans of untreated adult patients were imported into OnDemand3D software version 8.0 (Beach Road, Singapore). The seven variables suggested by Björk were measured for each scan. Subjects were grouped according to their mandibular plane angle into three groups; Hypodivergent, Normodivegent, and Hyperdivergent group. Median values of each of the seven variables were compared among the groups. Multinomial logistic regression was used to investigate the association between the seven variables and mandibular plane angle.
Results: Significant differences were found in medians of all seven signs among the three groups (P<0.001). Mandibular canal curvature and symphysis inclination were negatively associated with hypodivergence compared to normodivergence (OR=0.64, 95% CI=0.43-0.95 and OR=0.64, 95% CI=0.45-0.91, respectively). Symphysis inclination and antegonial notch were associated with higher odds of hyperdivergence compared to normodivergence (OR=1.46, 95%CI=1.01-2.05 and OR=6.67, 95%CI=1.22-36.4, respectively), while Intermolar angle was associated with lower odds of hyperdivergence compared to normodivergence (OR=0.25, 95%CI=0.10-0.65) at P <0.05.
Conclusion: The validity of Björk’s seven indicators using CBCT was conformed. Curvature of mandibular canal and inclination of symphysis are significant predictors for hypodivergence, while intermolar angle, inclination of symphysis, and antegonial notch are significant predictors for hyperdivergence. We recommend using Björk’s indicators on CBCT instead of lateral cephalometrics and apply our protocol in measuring them to help in generating accurate readings |
|
Supervisor |
: |
Prof. Ali Habiballah Hassan |
|
Thesis Type |
: |
Master Thesis |
|
Publishing Year |
: |
1442 AH
2020 AD |
|
Added Date |
: |
Sunday, January 17, 2021 |
|
Researchers
| نورا خليل شعبان | Shaban, Noura Khalil | Researcher | Master | |
|