scholarly journals Novel three-dimensional position analysis of the mandibular foramen in patients with skeletal class III mandibular prognathism

2016 ◽  
Vol 46 (2) ◽  
pp. 77
Author(s):  
Sang-Hoon Kang ◽  
Yeon-Ho Kim ◽  
Yu-Jin Won ◽  
Moon-Key Kim
2013 ◽  
Vol 83 (4) ◽  
pp. 623-629 ◽  
Author(s):  
Min-Ah Kim ◽  
Bo-Ram Kim ◽  
Jin-Young Choi ◽  
Jong-Kuk Youn ◽  
Yoon-Ji R. Kim ◽  
...  

ABSTRACT Objective: To evaluate longitudinal changes of the hyoid bone position and pharyngeal airway space after bimaxillary surgery in mandibular prognathism patients. Materials and Methods: Cone-beam computed tomography scans were taken for 25 mandibular prognathism patients before surgery (T0), 2 months after surgery (T1), and 6 months after surgery (T2). The positional displacement of the hyoid bone was assessed using the coordinates at T0, T1, and T2. Additionally, the volume of each subject's pharyngeal airway was measured. Results: The mean amount of posterior maxilla impaction was 3.76 ± 1.33 mm as the palatal plane rotated 2.04° ± 2.28° in a clockwise direction as a result of bimaxillary surgery. The hyoid bone moved backward (P < .05, P < .001) and downward (P > .05, P < .05) at 2 months and 6 months after surgery, while the total volume of the pharyngeal airway significantly decreased at the same time points (P < .001, P < .001). There was significant relationship between the changes of the hyoid bone position and airway volume at 2 months after surgery (P < .05). The change of the palatal plane angle was positively correlated to the decrease in the total airway volume (P < .001). Conclusions: The null hypothesis was rejected. The hyoid bone moved inferoposteriorly, and the pharyngeal airway volume decreased for up to 6 months after bimaxillary surgery. The decrease in the pharyngeal airway volume was correlated to the changes in the palatal plane inclination and the positional change of the hyoid bone.


Author(s):  
Anjana Atteeri ◽  
Praveen Kumar Neela ◽  
Pavan Kumar Mamillapalli ◽  
Vasu M. Sesham ◽  
Sreekanth Keesara ◽  
...  

Abstract Background Mandibular prognathism (MP) is a craniofacial deformity resulting from the combined effects of environmental and genetic factors. Although various linkage and genome-wide association studies for mandibular prognathism have identified multiple strongly associated regions and genes, the causal genes and variants responsible for the deformity remained ambiguous. Aim This research work was aimed to study the association between polymorphism rs10850110 of the MYO1H gene and skeletal class-III malocclusion in our local population. Materials and Methods Thirty patients with skeletal class III due to mandibular prognathism in the study group and 30 patients with skeletal class I in the control group were selected for this study. These patients were from both sexes and above age 10 years. Based on the cephalometric values, patients were categorized into study and control groups. SNB (angle between sella, nasion and point B at nasion) greater than 82 degrees with an ANB (angle between point A, nasion and point B at nasion) of less than 0 degrees in the study group and ANB (angle between point A, nasion and point B at nasion) of 2 to 4 degrees in the control group were categorized. The polymorphism (rs10850110) of the MYO1H gene was genotyped using polymerase chain reaction and restriction fragment length polymorphism. Associations were tested with SNP exact test using SNPstats software. Results The single-nucleotide polymorphism rs10850110 showed a statistically significant association with mandibular prognathism. The G allele of marker rs10850110 (5′ of myosin1H - MYO1H) was overrepresented when compared with the “A” allele in mandibular prognathism cases (p < 0.0001), and this was very significant. Conclusion These results suggest that the rs10850110 polymorphism of the MYO1H gene is associated with an increased risk for mandibular prognathism.


2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Chun-Ming Chen ◽  
Han-Jen Hsu ◽  
Ping-Ho Chen ◽  
Shih-Wei Liang ◽  
I-Ling Lin ◽  
...  

Purpose. This study investigated the relationship between the shortest buccal bone marrow of the ramus and skeletal patterns. Materials and Methods. Using cone-beam computed tomography data (specifically, the A point-nasion-B point (ANB) angle), we divided patients into three groups as follows: skeletal class I ( 0 ° < ANB < 4 ° ), class II (ANB: ≥4°), and class III (ANB: ≤0°). Sixteen vertical sections in the coronal plane were taken starting from slice 0 (original intact mandibular canal) anteriorly at 2 mm intervals to slice 15 (30 mm). The thickness of the mandible (M) and shortest buccal bone marrow (SBM) were measured. The data of SBM were divided into two groups ( SBM ≥ 1   mm and SBM < 1   mm ). For each skeletal pattern, an SBM   value < 1   mm was considered to indicate a high possibility of postoperative nerve paresthesia and bad split. Results. The three skeletal pattern groups also did not significantly differ in their M values for all sections. The mean SBM values of class III (0.91–2.11 mm) at 6–16 mm anterior to the mandibular foramen were significantly smaller than those of class II (1.53–3.17 mm). Comparing the occurrence ratio of SBM < 1   mm , the highest and lowest probabilities in class III (55% and 21.7%, respectively) were significantly larger at 6–20 mm anterior to the mandibular foramen than those in class II (28.3% and 5%, respectively). Conclusion. Class III had a significantly shorter SBM distance and higher SBM occurrence probability than class II at the mandibular ramus region, implying that class III participants are more likely than class II participants to have nerve paresthesia and bad split after sagittal split ramus osteotomy.


2019 ◽  
Vol 8 (12) ◽  
pp. 2106 ◽  
Author(s):  
Cheng-Ting Ho ◽  
Rafael Denadai ◽  
Hsin-Chih Lai ◽  
Lun-Jou Lo ◽  
Hsiu-Hsia Lin

Three-dimensional (3D) computer-aided simulation has revolutionized orthognathic surgery treatment, but scarce 3D cephalometric norms have been defined to date. The purposes of this study were to (1) establish a normative database of 3D Burstone cephalometric measurements for adult male and female Chinese in Taiwan, (2) compare this 3D norm dataset with the two-dimensional (2D) Burstone norms from Caucasian and Singaporean Chinese populations, and (3) apply these 3D norms to assess the outcome of a computer-aided simulation of orthognathic surgery. Three-dimensional Burstone cephalometric analysis was performed on 3D digital craniofacial image models generated from cone-beam computed tomography datasets of 60 adult Taiwanese Chinese individuals with normal occlusion and balanced facial profile. Three-dimensional Burstone analysis was performed on 3D image datasets from patients with skeletal Class III pattern (n = 30) with prior computer-aided simulation. Three-dimensional Burstone cephalometric measurements showed that Taiwanese Chinese males had significantly (p < 0.05) larger anterior and posterior facial heights, maxillary length, and mandibular ramus height than females, with no significant (p > 0.05) difference for facial soft-tissue parameters. The 3D norm dataset revealed Taiwanese Chinese-specific facial characteristics, with Taiwanese presenting (p < 0.05) a more convex profile, protrusive maxillary apical bases, protruding mandible, protruding upper and lower lips, and a shorter maxillary length and lower facial height than Caucasians. Taiwanese had significantly (p < 0.05) larger maxillary projection, vertical height ratio, lower face throat angle, nasolabial angle, and upper lip protrusion than Singaporean Chinese. No significant (p > 0.05) difference was observed between 3D norms and computer-aided simulation-derived 3D patient images for horizontal skeletal, vertical skeletal, and dental measurements, with the exception of two dental parameters (p < 0.05). This study contributes to literature by providing gender- and ethnic-specific 3D Burstone cephalometric norms, which can assist in the multidisciplinary-based delivery of orthodontic surgical care for Taiwanese Chinese individuals worldwide, including orthodontic management, computer-assisted simulation, and outcome assessment.


Sign in / Sign up

Export Citation Format

Share Document