scholarly journals Comparison of Changes in the Condylar Volume and Morphology in Skeletal Class III Deformities Undergoing Orthognathic Surgery Using a Customized versus Conventional Miniplate: A Retrospective Analysis

2020 ◽  
Vol 9 (9) ◽  
pp. 2794
Author(s):  
You Na Lim ◽  
In-Young Park ◽  
Jong-Cheol Kim ◽  
Soo-Hwan Byun ◽  
Byoung-Eun Yang
Keyword(s):  
Conventional Method ◽  
Three Dimensional ◽  
Patient Specific ◽  
Computer Assisted ◽  
Class Iii ◽  
Specific System ◽  
Sagittal Split Ramus Osteotomy ◽  
Skeletal Class ◽  
Surgical Technology ◽  
Significant Difference

With the great leap in the development of three-dimensional computer-assisted surgical technology, surgeons can use a variety of assistive methods to achieve better results and evaluate surgical outcomes in detail. This retrospective study aimed to evaluate the postoperative stability after bilateral sagittal split ramus osteotomy by volume rendering methods and to evaluate how postoperative stability differs depending on the type of surgical plate. Of the patients who underwent BSSRO, ten patients in each group (non-customized miniplate and customized miniplate) who met the inclusion criteria were selected. Preoperative and postoperative cone-beam computed tomography data were collected, and condylar morphological and landmark measurements were obtained using Checkpoint and OnDemand software, respectively. The postoperative condylar morphological dataset revealed no significant difference (p > 0.05) between the two groups. No significant difference (p > 0.05) was observed between the two groups in horizontal, vertical, or angular landmark measurements used to quantify operational stability. These results indicate that there is no difference in the surgical outcome between the patient-specific system and the conventional method, which will allow clinicians to take advantage of the patient-specific system for this surgical procedure, with favorable results, as with the conventional method.

scholarly journals Computer-Aided Planning in Orthognathic Surgery: A Comparative Study with the Establishment of Burstone Analysis-Derived 3D Norms

2019 ◽  
Vol 8 (12) ◽  
pp. 2106 ◽  
Author(s):  
Cheng-Ting Ho ◽  
Rafael Denadai ◽  
Hsin-Chih Lai ◽  
Lun-Jou Lo ◽  
Hsiu-Hsia Lin
Keyword(s):  
Orthognathic Surgery ◽  
Three Dimensional ◽  
Computer Assisted ◽  
Class Iii ◽  
Facial Soft Tissue ◽  
Skeletal Class ◽  
Nasolabial Angle ◽  
Normal Occlusion ◽  
Computer Aided ◽  
Cephalometric Measurements

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.

scholarly journals 3D CBCT Evaluation of Condyle Position in Skeletal Class I & Class III Growing Subjects

2018 ◽  
Vol 7 (2) ◽  
pp. 9-14
Author(s):  
Rajiv Kumar Mishra ◽  
Om Prakash Kharbanda ◽  
Rajiv Balachandran
Keyword(s):  
Three Dimensional ◽  
T Test ◽  
Class I ◽  
Class Iii ◽  
Skeletal Class ◽  
Significant Difference ◽  
Condyle Position ◽  
Condylar Position ◽  
And Function ◽  
Cbct Analysis

Introduction: Evaluation of temporo-mandibular joint (TMJ) anatomy and function is an essential part of orthodontic diagnosis and treatment planning. It has been hypothesized that dental and skeletal malocclusions alter the functional loading of TMJ which can affect joint morphology.Objective: Three dimensional (3D) evaluation of condylar position using CBCT in skeletal Class I and Class III growing subjects.Materials & Method: CBCT images of ten growing skeletal Class I & ten Class III patients in the age range of 7-14 years were analyzed. 3D condylar position were evaluated representing antero-posterior, vertical, laterolateral position of condyle, axial condylar angle and coronal condylar angles which were measured in axial, coronal and sagittal sections using Dolphin Imaging software. Antero-posterior and vertical difference of right and left condyle were measured in axial and coronal sections respectively.Result: Paired t-Test revealed no significant difference between right and left sides of condyle in skeletal Class I as well as Class III subjects. Independent t-test and Mann-Whitney U test showed no significant difference between position of condyle in ClassI and Class III subjects.Conclusion: 3D CBCT analysis shows no significant difference in condylar position of skeletal Class I and Class III subjects.

scholarly journals The outcome of skeletofacial reconstruction with mandibular rotation for management of asymmetric skeletal class III deformity: A three-dimensional computer-assisted investigation

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Ting-Yu Wu ◽  
Rafael Denadai ◽  
Hsiu-Hsia Lin ◽  
Cheng-Ting Ho ◽  
Lun-Jou Lo
Keyword(s):  
Three Dimensional ◽  
Mouth Opening ◽  
Facial Asymmetry ◽  
Computer Assisted ◽  
Rigid Fixation ◽  
Class Iii ◽  
Class Iii Malocclusion ◽  
Skeletal Class ◽  
Jaw Surgery

Abstract The mandibular proximal ramus segments should be moved and rotated during orthognathic surgery-based skeletofacial reconstruction for the correction of challenging patients with facial asymmetry and malocclusion, but quantitative data regarding this rotation were not sufficient to date. This 3D computer-assisted study measured the proximal ramus segment rotation after 3D simulation-guided two-jaw surgery in patients with facial asymmetric deformity and class III malocclusion (n = 31). Using 3D mandible models and a reliable proximal ramus segment-related plane, angular changes in pitch, roll and yaw directions were measured before and one month after surgery. Significant rotational changes (p < 0.01) were observed in the left and right sides and overall proximal ramus segments after surgery, with absolute differences of 4.1 ± 3.0 (range −7.8 to 6.9), 2.8 ± 2.3 (−8.8 to 5.0), and 2.7 ± 2.4 (−6.6 to 9.9) degrees in pitch, roll, and yaw rotations, respectively. Numbness and mouth opening limiting occurred within the first 6 months after surgery but the patients had an unremarkable long-term postoperative course, with no revisionary surgery required. This study contributes to the multidisciplinary-related literature by revealing that proximal ramus segment rotation and rigid fixation with no postoperative intermaxillary immobilization was practicable in skeletofacial surgery for the successful treatment of asymmetric deformity and class III malocclusion.

scholarly journals Sagittal Split Ramus Osteotomy in the Shortest Buccal Bone Marrow Distances of the Mandible on the Coronal Plane

2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Chun-Ming Chen ◽  
Han-Jen Hsu ◽  
Ping-Ho Chen ◽  
Shih-Wei Liang ◽  
I-Ling Lin ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Mandibular Canal ◽  
Class Ii ◽  
Coronal Plane ◽  
Class Iii ◽  
Sagittal Split Ramus Osteotomy ◽  
Mandibular Foramen ◽  
Skeletal Class ◽  
Skeletal Pattern ◽  
The Relationship

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.

Investigation of three-dimensional printing materials for printing aorta model replicating Type B aortic dissection

2021 ◽  
Vol 17 ◽  
Author(s):  
Chia-An Wu ◽  
Andrew Squelch ◽  
Zhonghua Sun
Keyword(s):  
3D Printing ◽  
Aortic Dissection ◽  
Three Dimensional ◽  
Ct Images ◽  
Patient Specific ◽  
Type B ◽  
Type B Aortic Dissection ◽  
Ct Attenuation ◽  
Significant Difference ◽  
3D Printed

Aim: To determine a printing material that has both elastic property and radiology equivalence close to real aorta for simulation of endovascular stent graft repair of aortic dissection. Background: With the rapid development of three-dimensional (3D) printing technology, a patient-specific 3D printed model is able to help surgeons to make better treatment plan for Type B aortic dissection patients. However, the radiological properties of most 3D printing materials have not been well characterized. This study aims to investigate the appropriate materials for printing human aorta with mechanical and radiological properties similar to the real aortic computed tomography (CT) attenuation. Objective: Quantitative assessment of CT attenuation of different materials used in 3D printed models of aortic dissection for developing patient-specific 3D printed aorta models to simulate type B aortic dissection. Method: A 25-mm length of aorta model was segmented from a patient’s image dataset with diagnosis of type B aortic dissection. Four different elastic commercial 3D printing materials, namely Agilus A40 and A50, Visijet CE-NT A30 and A70 were selected and printed with different hardness. Totally four models were printed out and conducted CT scanned twice on a 192-slice CT scanner using the standard aortic CT angiography protocol, with and without contrast inside the lumen.Five reference points with region of interest (ROI) of 1.77 mm2 were selected at the aortic wall and intimal flap and their Hounsfield units (HU) were measured and compared with the CT attenuation of original CT images. The comparison between the patient’s aorta and models was performed through a paired-sample t-test to determine if there is any significant difference. Result: The mean CT attenuation of aortic wall of the original CT images was 80.7 HU. Analysis of images without using contrast medium showed that the material of Agilus A50 produced the mean CT attenuation of 82.6 HU, which is similar to that of original CT images. The CT attenuation measured at images acquired with other three materials was significantly lower than that of original images (p<0.05). After adding contrast medium, Visijet CE-NT A30 had an average CT attenuation of 90.6 HU, which is close to that of the original images with statistically significant difference (p>0.05). In contrast, the CT attenuation measured at images acquired with other three materials (Agilus A40, A50 and Visiject CE-NT A70) was 129 HU, 135 HU and 129.6 HU, respectively, which is significantly higher than that of original CT images (p<0.05). Conclusion: Both Visijet CE-NT and Agilus have tensile strength and elongation close to real patient’s tissue properties producing similar CT attenuation. Visijet CE-NT A30 is considered the appropriate material for printing aorta to simulate contrast-enhanced CT imaging of type B aortic dissection. Due to lack of body phantom in the experiments, further research with simulation of realistic anatomical body environment should be conducted.

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