scholarly journals Three-dimensional assessment of the anterior and inferior loop of the inferior alveolar nerve using computed tomography images in patients with and without mandibular asymmetry

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jae-Young Kim ◽  
Michael D. Han ◽  
Kug Jin Jeon ◽  
Jong-Ki Huh ◽  
Kwang-Ho Park
Keyword(s):  
Computed Tomography ◽  
Symmetry Group ◽  
Three Dimensional ◽  
Inferior Alveolar Nerve ◽  
Mental Foramen ◽  
3D Analysis ◽  
Mandibular Asymmetry ◽  
Computed Tomography Images ◽  
Significant Difference ◽  
Mandibular Body

Abstract Background The purpose of this study was to investigate the differences in configuration and dimensions of the anterior loop of the inferior alveolar nerve (ALIAN) in patients with and without mandibular asymmetry. Method Preoperative computed tomography images of patients who had undergone orthognathic surgery from January 2016 to December 2018 at a single institution were analyzed. Subjects were classified into two groups as “Asymmetry group” and “Symmetry group”. The distance from the most anterior and most inferior points of the ALIAN (IANant and IANinf) to the vertical and horizontal reference planes were measured (dAnt and dInf). The distance from IANant and IANinf to the mental foramen were also calculated (dAnt_MF and dInf_MF). The length of the mandibular body and symphysis area were measured. All measurements were analyzed using 3D analysis software. Results There were 57 total eligible subjects. In the Asymmetry group, dAnt and dAnt_MF on the non-deviated side were significantly longer than the deviated side (p < 0.001). dInf_MF on the non-deviated side was also significantly longer than the deviated side (p = 0.001). Mandibular body length was significantly longer on the non-deviated side (p < 0.001). There was no significant difference in length in the symphysis area (p = 0.623). In the Symmetry group, there was no difference between the left and right sides for all variables. Conclusion In asymmetric patients, there is a difference tendency in the ALIAN between the deviated and non-deviated sides. In patients with mandibular asymmetry, this should be considered during surgery in the anterior mandible.

scholarly journals PREVALENCE OF MANDIBULAR ASYMMETRY IN SKELETAL CLASS I ADULT PATIENTS

2014 ◽  
Vol 2 (2) ◽  
pp. 189 ◽  
Author(s):  
Bruno Frazão Gribel ◽  
Guilherme Thiesen ◽  
Tássia Silvana Borges ◽  
Maria Perpétua Mota Freitas
Keyword(s):  
Computed Tomography ◽  
Calculation Method ◽  
Significant Error ◽  
Adult Patients ◽  
Class I ◽  
Cone Beam ◽  
Skeletal Class ◽  
Mandibular Asymmetry ◽  
Computed Tomography Images ◽  
Significant Difference

AIM: The objective of this study was evaluating the prevalence of mandibular asymmetry in skeletal Class I adult patients. MATERIALS AND METHODS: The sample was composed by cone-beam computed tomography images of 250 skeletal Class I patients with age from 18 to 70 years old. The side deviation of mandibular asymmetry was evaluated (right and left), as well as the intensity of this asymmetry. People with gnathic deviation until 2mm were considered as patients with slight asymmetry; deviation between 2 and 5mm was considered moderate asymmetry and those higher than 5mm as severe asymmetries. The error calculation method was performed and there was not significant error in the measurements. To verify the association between the prevalence of mandibular asymmetry and the gender of individuals, the Χ2 was carried out and the significant level adopted was 5% (p<0.05). RESULTS: The results showed that mandibular deviation occurred more frequently to the left side in both genders (male 56.5% e female 58.2%), without statistically significant difference between them (p=0.792). Besides, the prevalence of slight, moderate and severe asymmetries were, respectively 61%, 27% and 12% for males and 54%, 28% and 18% for female; and there was not statistically significant difference (p=0.366) between the gender of the sample evaluated. CONCLUSION: In this study, both deviation and intensity of mandibular asymmetry did not present preference regarding to the gender.

scholarly journals Three-dimensional characterization of mandibular asymmetry in craniofacial microsomia

2020 ◽  
Vol 24 (12) ◽  
pp. 4363-4372
Author(s):  
Yun-Fang Chen ◽  
Frank Baan ◽  
Robin Bruggink ◽  
Ewald Bronkhorst ◽  
Yu-Fang Liao ◽  
...  
Keyword(s):  
Average Distance ◽  
Three Dimensional ◽  
Contralateral Side ◽  
Individual Variability ◽  
Distance Map ◽  
Mandibular Asymmetry ◽  
Computed Tomography Images ◽  
Craniofacial Microsomia ◽  
Mandibular Body ◽  
Treatment Plans

Abstract Objectives This study aimed to investigate the three-dimensional (3D) mandibular asymmetry in craniofacial microsomia (CFM) and its association with the Pruzansky–Kaban classification system. Materials and methods Cone-beam computed tomography images of 48 adult CFM cases were collected. The asymmetry of the mandibular body and ramus was analyzed with 3D landmarks. The mirrored mandibular model was registered on the original model, yielding a color-coded distance map and an average distance (i.e., asymmetry score) to quantify the overall mandibular asymmetry. Results The lengths of the mandibular body and ramus were significantly shorter on the affected than the contralateral side (p < 0.001). The ANB (p = 0.009), body and ramal lengths (both p < 0.001), and body and ramal length asymmetry (both p < 0.05) were significantly different between mild (types I/IIA) and severe (types IIB/III) cases. The mandibular asymmetry score correlated with mandibular body length asymmetry (r = 0.296, p = 0.046). CFM mandibles showed high variability in shape asymmetry. Conclusions CFM patients showed distinct body and ramal length asymmetries. In severe cases, mandibles were smaller, more retruded, and more asymmetric in length. The mandibular shape asymmetry was highly variable regardless of the Pruzansky–Kaban types, being a determinant in the extent of overall mandibular asymmetry. Clinical relevance The 3D morphologic analysis provides better insights into real mandibular asymmetry. Although the Pruzansky–Kaban classification was applied, high individual variability of the mandibular morphology still existed within the types. Therefore, individualized analyses and treatment plans for CFM patients are highly recommended.

scholarly journals Comparing the Use of 3D Photogrammetry and Computed Tomography in Assessing the Severity of Single-Suture Nonsyndromic Craniosynostosis

2017 ◽  
Vol 25 (2) ◽  
pp. 78-83 ◽  
Author(s):  
Olivia A. Ho ◽  
Nikoo Saber ◽  
Derek Stephens ◽  
April Clausen ◽  
James Drake ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Soft Tissue ◽  
Confidence Interval ◽  
Three Dimensional ◽  
Computed Tomography Images ◽  
Younger Age ◽  
Significant Difference ◽  
3D Photogrammetry ◽  
The Mean ◽  
Single Suture

Purpose: Single-suture nonsyndromic craniosynostosis is diagnosed using clinical assessment and computed tomography (CT). With increasing awareness of the associated risks of radiation exposure, the use of CT is particularly concerning in patients with craniosynostosis since they are exposed at a younger age and more frequently than the average child. Three-dimensional (3D) photogrammetry is advantageous—it involves no radiation, is conveniently obtainable within clinic, and does not require general anaesthesia. This study aims to assess how 3D photogrammetry compares to CT in the assessment of craniosynostosis severity, to quantify surgical outcomes, and analyze the validity of 3D photogrammetry in craniosynostosis. Methods: Computed tomography images and 3D photographs of patients who underwent craniosynostosis surgery were assessed and aligned to best fit. The intervening area between the CT and 3D photogrammetry curves at the supraorbital bar (bandeau) level in axial view was calculated. Statistical analysis was performed using Student t test. Ninety-five percent confidence intervals were determined and equivalence margins were applied. Results: In total, 41 pairs of CTs and 3D photographs were analyzed. The 95% confidence interval was 198.16 to 264.18 mm2 and the mean was 231.17 mm2. When comparisons were made in the same bandeau region omitting the temporalis muscle, the 95% confidence interval was 108.94 to 147.38 mm2, and the mean was 128.16 mm2. Although statistically significant difference between the modalities was found, they can be attributable to the dampening effect of soft tissue. Conclusion: Within certain error margins, 3D photogrammetry is comparable to CT in assessing the severity of single-suture nonsyndromic craniosynostosis. However, a dampening effect can be attributable to the soft tissue. Three-dimensional photogrammetry may be more applicable for severe cases of craniosynostosis but not milder deformity. It may also be beneficial for assessing the overall appearance and aesthetics but not for determining underlying bony severity.

scholarly journals Digit Bones (Acropodium) of Gazella (Gazella subgutturosa); Three-Dimensional Modelling and Morphometry

2021 ◽  
Vol 41 (04) ◽  
pp. 481-486
Author(s):  
Ismail Demircioglu
Keyword(s):  
Computed Tomography ◽  
Three Dimensional ◽  
Male Adult ◽  
Three Dimensional Modeling ◽  
Surface Areas ◽  
Computed Tomography Images ◽  
Significant Difference ◽  
Three Dimensional Models ◽  
The Right ◽  
Gazella Subgutturosa

The present study was conducted to identify morphometric values and to reveal differences between sexes through three-dimensional modeling of digit bones (ossa phalanges) of gazella by using computed tomography images. A total of 14 (7 female, 7 male) adult gazella (Gazella subgutturosa) cadavers were used in the study. The images were extracted by scanning acropodium bones of gazella at 64-detector Multi Detector Computed Tomography (MDCT) in cross section thickness of 0.625mm. Using MIMICS 20.1 program, three-dimensional models of these images were prepared and morphometric measurements were taken. In GLpe and Bd measurements of Phalanx proximalis, a statistically significant difference was established between females and males in terms of the left forelimb internal, the right forelimb internal, the right forelimb external, and the right hindlimb external bones (P<0.05). There was a statistically significant difference between females and males in terms of volume of phalanx proximalis and surface area of the right forelimb internal phalanx proximalis (P<0.001). In GLpe measurements, a statistically significant difference was determined between females and males in terms of the left forelimb internal, the right forelimb internal, the right hindlimb internal, the left forelimb external, the right forelimb external, and the right hindlimb external phalanx media (P<0.05). A statistically significant difference was determined between females and males in terms of the data related to volume and surface areas of the left hindlimb internal the right hindlimb internal, the left hindlimb external, and the right hindlimb external phalanx distalis (P<0.05).

scholarly journals Reproducibility of landmark identification in the jaw and teeth on 3-dimensional cone-beam computed tomography images

2011 ◽  
Vol 81 (5) ◽  
pp. 843-849 ◽  
Author(s):  
Mariko Fuyamada ◽  
Hiroyuki Nawa ◽  
Momoko Shibata ◽  
Kazuhito Yoshida ◽  
Yoshitaka Kise ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Cone Beam Computed Tomography ◽  
Three Dimensional ◽  
Cone Beam ◽  
Volume Data ◽  
3D Images ◽  
3 Dimensional ◽  
Computed Tomography Images ◽  
Landmark Identification ◽  
Significant Difference

Abstract Objective: To compare the reproducibility of landmark identification on three-dimensional (3D) cone-beam computed tomography (CBCT) images between procedures based on traditional cephalometric definitions (procedure 1) and those tentatively proposed for 3D images (procedure 2). Materials and Methods: A phantom with embedded dried human skull was scanned using CBCT. The acquired volume data were transferred to a personal computer, and 3D images were reconstructed. Eighteen dentists plotted nine landmarks related to the jaws and teeth four times: menton (Me), pogonion (Po), upper-1 (U1), lower-1 (L1), left upper-6 (U6), left lower-6 (L6), gonion (Go), condyle (Cd), and coronoid process (Cp). The plotting reliabilities of the two procedures were compared by calculating standard deviations (SDs) in three components (x, y, and z) of coordinates and volumes of 95% confidence ellipsoid. Results: All 27 SDs for procedure 2 were less than 1 mm, and only five of them exceeded 0.5 mm. The variations were significantly different between the two procedures, and the SDs of procedure 2 were smaller than those of procedure 1 in 21 components of coordinates. The ellipsoid volumes were also smaller for procedure 2 than procedure 1, although a significant difference was not found. Conclusions: Definitions determined strictly on each three sectional images, such as for procedure 2, were required for sufficient reliability in identifying the landmark related to the jaws and teeth.

scholarly journals Tibia vara in Asians: Myth or fact? Verification with three-dimensional computed tomography

2021 ◽  
Vol 29 (1) ◽  
pp. 230949902199261
Author(s):  
Jade Pei Yuik Ho ◽  
Azhar Mahmood Merican ◽  
Khairul Anwar Ayob ◽  
Shahrul-Hisham Sulaiman ◽  
Muhammad Sufian Hashim
Keyword(s):  
Computed Tomography ◽  
Three Dimensional ◽  
3D Analysis ◽  
3 Dimensional ◽  
Significant Difference ◽  
Males And Females ◽  
The Mean ◽  
Post Hoc ◽  
Best Fit ◽  
Standard Frame

Background: There is a common perception among surgeons that Asian tibiae are significantly more varus compared to non-Asians, contributed both by an acute medial tibial proximal angle (MPTA) and diaphyseal bowing. Insight into the normative morphology of the tibia allows generation of knowledge towards disease processes and subsequently planning for corrective surgeries. Methods: Computed tomography (CT) scans of 100 normal adult knees, aged 18 years and above, were analysed using a 3-dimensional (3D) analysis software. All tibiae were first aligned to a standard frame of reference and then rotationally aligned to the tibial centroid axis (TCAx) and the transmalleolar axis (tmAx). MPTA was measured from best-fit planes on the surface of the proximal tibia for each rotational alignment. Diaphyseal bowing was assessed by dividing the shaft to three equal portions and establishing the angle between the proximal and distal segments. Results: The mean MPTA was 87.0° ± 2.2° (mean ± SD) when rotationally aligned to TCAx and 91.6° ± 2.7° when aligned to tmAx. The mean diaphyseal bowing was 0.1° ± 1.9° varus when rotationally aligned to TCAx and 0.3° ± 1.6° valgus when aligned to tmAx. The mean difference when the MPTA was measured with two different rotational alignments (TCAx and tmAx) was 4.6° ± 2.3°. No statistically significant differences were observed between males and females. Post hoc tests revealed statistically significant difference in MPTA between different ethnic sub-groups. Conclusion: The morphology of the proximal tibiae in the disease-free Asian knee is inherently varus but not more so than other reported populations. The varus profile is contributed by the MPTA, with negligible diaphyseal bowing. These implications are relevant to surgical planning and prosthesis design.

scholarly journals Immersive 3D virtual reality imaging in planning minimally invasive and complex adult cardiac surgery

2020 ◽  
Vol 1 (1) ◽  
pp. 62-70
Author(s):  
Amir H Sadeghi ◽  
Wouter Bakhuis ◽  
Frank Van Schaagen ◽  
Frans B S Oei ◽  
Jos A Bekkers ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Virtual Reality ◽  
Cardiac Surgery ◽  
Heart Surgery ◽  
Preoperative Planning ◽  
Operating Time ◽  
Three Dimensional ◽  
Cardiothoracic Surgery ◽  
Planning Tool ◽  
Computed Tomography Images

Abstract Aims Increased complexity in cardiac surgery over the last decades necessitates more precise preoperative planning to minimize operating time, to limit the risk of complications during surgery and to aim for the best possible patient outcome. Novel, more realistic, and more immersive techniques, such as three-dimensional (3D) virtual reality (VR) could potentially contribute to the preoperative planning phase. This study shows our initial experience on the implementation of immersive VR technology as a complementary research-based imaging tool for preoperative planning in cardiothoracic surgery. In addition, essentials to set up and implement a VR platform are described. Methods Six patients who underwent cardiac surgery at the Erasmus Medical Center, Rotterdam, The Netherlands, between March 2020 and August 2020, were included, based on request by the surgeon and availability of computed tomography images. After 3D VR rendering and 3D segmentation of specific structures, the reconstruction was analysed via a head mount display. All participating surgeons (n = 5) filled out a questionnaire to evaluate the use of VR as preoperative planning tool for surgery. Conclusion Our study demonstrates that immersive 3D VR visualization of anatomy might be beneficial as a supplementary preoperative planning tool for cardiothoracic surgery, and further research on this topic may be considered to implement this innovative tool in daily clinical practice. Lay summary Over the past decades, surgery on the heart and vessels is becoming more and more complex, necessitating more precise and accurate preoperative planning. Nowadays, operative planning is feasible on flat, two-dimensional computer screens, however, requiring a lot of spatial and three-dimensional (3D) thinking of the surgeon. Since immersive 3D virtual reality (VR) is an upcoming imaging technique with promising results in other fields of surgery, we aimed in this study to explore the additional value of this technique in heart surgery. Our surgeons planned six different heart operations by visualizing computed tomography scans with a dedicated VR headset, enabling them to visualize the patient’s anatomy in an immersive and 3D environment. The outcomes of this preliminary study are positive, with a much more reality-like simulation for the surgeon. In such, VR could potentially be beneficial as a preoperative planning tool for complex heart surgery.

Total Wrist Arthroplasty Alignment and Its Potential Association with Clinical Outcomes

2021 ◽  
Author(s):  
Bardiya Akhbari ◽  
Kalpit N. Shah ◽  
Amy M. Morton ◽  
Janine Molino ◽  
Douglas C. Moore ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Clinical Outcomes ◽  
Three Dimensional ◽  
Radial Component ◽  
Single Type ◽  
Radiographic Images ◽  
Computed Tomography Images ◽  
Total Wrist Arthroplasty ◽  
Flexion Extension ◽  
Wrist Arthroplasty

Abstract Purpose There is a lack of quantitative research that describes the alignment and, more importantly, the effects of malalignment on total wrist arthroplasty (TWA). The main goal of this pilot study was to assess the alignment of TWA components in radiographic images and compare them with measures computed by three-dimensional analysis. Using these measures, we then determined if malalignment is associated with range of motion (ROM) or clinical outcomes (PRWHE, PROMIS, QuickDash, and grip strength). Methods Six osteoarthritic patients with a single type of TWA were recruited. Radiographic images, computed tomography images, and clinical outcomes of the wrists were recorded. Using posteroanterior and lateral radiographs, alignment measurements were defined for the radial and carpal components. Radiographic measurements were validated with models reconstructed from computed tomography images using Bland–Altman analysis. Biplanar videoradiography (<1mm and <1 degree accuracy) was used to capture and compute ROM of the TWA components. Linear regression assessed the associations between alignment and outcomes. Results Radiographic measures had a 95% limit-of-agreement (mean difference ±  1.96 × SD) of 3 degrees and 3mm with three-dimensional values, except for the measures of the carpal component in the lateral view. In our small cohort, wrist flexion–extension and radial–ulnar deviation were correlated with volar–dorsal tilt and volar–dorsal offset of the radial component and demonstrated a ROM increase of 3.7 and 1.6 degrees per degree increase in volar tilt, and 10.8 and 4.2 degrees per every millimeter increase in volar offset. The carpal component's higher volar tilt was also associated with improvements in patient-reported pain. Conclusions We determined metrics describing the alignment of TWA, and found the volar tilt and volar offset of the radial component could potentially influence the replaced wrist's ROM. Clinical Relevance TWA component alignment can be measured reliably in radiographs, and may be associated with clinical outcomes. Future studies must evaluate its role in a larger cohort.

Utility of three-dimensional and reformatted head computed tomography images in the evaluation of pediatric abusive head trauma

2021 ◽  
Author(s):  
Rangarajan Purushothaman ◽  
Shivang Desai ◽  
Sateesh Jayappa ◽  
Arabinda K. Choudhary ◽  
Raghu H. Ramakrishnaiah
Keyword(s):  
Computed Tomography ◽  
Head Trauma ◽  
Three Dimensional ◽  
Abusive Head Trauma ◽  
Computed Tomography Images ◽  
Head Computed Tomography

scholarly journals Dimensional Accuracy of Dental Models for Three-Unit Prostheses Fabricated by Various 3D Printing Technologies

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1550
Author(s):  
Soo-Yeon Yoo ◽  
Seong-Kyun Kim ◽  
Seong-Joo Heo ◽  
Jai-Young Koak ◽  
Joung-Gyu Kim
Keyword(s):  
Surface Roughness ◽  
Three Dimensional ◽  
Dimensional Accuracy ◽  
3D Analysis ◽  
Digital Light Processing ◽  
Test Models ◽  
Reference File ◽  
Significant Difference ◽  
Jet Printing ◽  
3D Printed

Previous studies on accuracy of three-dimensional (3D) printed model focused on full arch measurements at few points. The aim of this study was to examine the dimensional accuracy of 3D-printed models which were teeth-prepped for three-unit fixed prostheses, especially at margin and proximal contact areas. The prepped dental model was scanned with a desktop scanner. Using this reference file, test models were fabricated by digital light processing (DLP), Multi-Jet printing (MJP), and stereo-lithography apparatus (SLA) techniques. We calculated the accuracy (trueness and precision) of 3D-printed models on 3D planes, and deviations of each measured points at buccolingual and mesiodistal planes. We also analyzed the surface roughness of resin printed models. For overall 3D analysis, MJP showed significantly higher accuracy (trueness) than DLP and SLA techniques; however, there was not any statistically significant difference on precision. For deviations on margins of molar tooth and distance to proximal contact, MJP showed significantly accurate results; however, for a premolar tooth, there was no significant difference between the groups. 3D color maps of printed models showed contraction buccolingually, and surface roughness of the models fabricated by MJP technique was observed as the lowest. The accuracy of the 3D-printed resin models by DLP, MJP, and SLA techniques showed a clinically acceptable range to use as a working model for manufacturing dental prostheses

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