Browsing by Subject "CBCT"

Now showing 1 - 5 of 5
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    Comparative Assessment of Pharyngeal Airway Dimensions in Skeletal Class I, II, and III Emirati Subjects: A Cone Beam Computed Tomography Study
    (MDPI, 2024-09-25) AlAskar, Sara; Jamal, Mohamed; Khamis, Amar Hassan; Ghoneima, Ahmed; Orthodontics and Oral Facial Genetics, School of Dentistry
    The aim of the current study was to evaluate the pharyngeal airway dimensions of individuals with different skeletal patterns in a cohort of the Emirati population. The specific aim was to assess the relationship between pharyngeal airway dimensions and anterior facial height in relation to different skeletal patterns. This retrospective study was conducted on a sample of 103 CBCT scans of adult Emirati subjects categorized into three groups according to their skeletal classification as indicated by the ANB angle: Class I (n = 35), Class II (n = 46), and Class III (n = 22). All CBCT scans were taken using an i-CAT CBCT imaging machine (Imaging Sciences, Hatfield, PA, USA). The age range of the patients was 19 to 68 years (62 women and 41 men). ANOVA, t-tests, Kruskal-Wallis, and Mann-Whitney tests were employed for comparing means among groups. The correlation coefficient was used to evaluate the association between variables. A p-value of less than 0.05 was considered statistically significant. This study revealed significant associations between various airway parameters and cephalometric measurements. Positive correlations were observed between nasal cavity volume and nasopharynx volume, as well as anterior facial height. Oropharynx volume exhibited positive correlations with hypopharynx volume and total airway volume, and negative correlations with overjet, ANB angle, and patient age. Hypopharynx volume correlated positively with total airway volume and the most constricted area of the airway (MCA). Total airway volume showed positive correlations with MCA and anterior facial height. MCA had negative correlations with ANB angle and patient age. Nasopharynx volume was significantly larger in the skeletal Class I group than in the Class II or Class III groups, while the other airway parameters showed no significant differences among the groups (p > 0.05). Several airway parameters showed a correlation with anterior facial height among the different skeletal patterns. Nasopharyngeal airway volume was significantly larger in the skeletal Class I group than in Class II and III groups in the studied sample.
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    Cone beam CT evaluation of the presence of anatomic accessory canals in the jaws
    (2014-05) Eshak, M; Brooks, S; Abdel-Wahed, N; Edwards, Paul C.
    Objectives: To assess the prevalence, location and anatomical course of accessory canals of the jaws using cone beam CT. Methods: A retrospective analysis of 4200 successive cone beam CT scans, for patients of both genders and ages ranging from 7 to 88 years, was performed. They were exposed at the School of Dentistry, University of Michigan, Ann Arbor, MI. After applying the exclusion criteria (the presence of severe ridge resorption, pre-existing implants, a previously reported history of craniofacial malformations or syndromes, a previous history of trauma or surgery, inadequate image quality and subsequent scans from the same individuals), 4051 scans were ultimately included in this study. Results: Of the 4051 scans (2306 females and 1745 males) that qualified for inclusion in this study, accessory canals were identified in 1737 cases (42.9%; 1004 females and 733 males). 532 scans were in the maxilla (13.1%; 296 females and 236 males) and 1205 in the mandible (29.8%; 708 females and 497 males). Conclusions: A network of accessory canals bringing into communication the inner and outer cortical plates of the jaws was identified. In light of these findings, clinicians should carefully assess for the presence of accessory canals prior to any surgical intervention to decrease the risk for complications.
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    Evaluating the use of 3D imaging in creating a canal-directed endodontic access
    (2015-06-09) Maru, Avni Mahendra; Spolnik, Kenneth Jacob, 1950-; Ghoneima, Ahmed; Bringas, Josef; Warner, Ned A. (Ned Alan); Zunt, Susan L., 1951-; Ehrlich, Ygal
    Introduction: During root canal treatment (RCT), an opening is made through the crown of the tooth to access and to disinfect the root canal system (RCS). Traditional endodontic access (TEA) may sacrifice tooth structure and weaken the tooth. Cone beam computed tomography (CBCT) provides information about the exact location of the root canals. This information can be used for the design of a canal-directed endodontic access (CDEA). It may also be used for the 3D printing of an acrylic endodontic stent that could help to create a conservative CDEA. Objective: 1) Evaluate the ability of the Dolphin 3D imaging software to assist in creating a CDEA; 2) Compare tooth structure loss in a CDEA to that in a TEA by measuring the volume of remaining tooth structure, surface area of the access opening at the occlusal, and remaining dentin thickness at the CEJ. Materials and Methods: Thirty extracted human mandibular premolars were used. Teeth with large, wide canals were excluded. CBCT images will be taken for all teeth using Kodak 9000. Fifteen teeth were randomly assigned to the TEA group and 15 teeth were assigned to the CDEA group. The CDEA path was mapped using Dolphin 3D imaging software. Acrylic access stents were designed using Rhino 3D software and printed using a 3D printer. The teeth were accessed through the corresponding stents. The 15 teeth that are part of the traditional access group were accessed without a stent. A CBCT scan was taken post-access for all 30 teeth. Wilcoxon Rank Sum Tests were performed to compare the following outcomes for the two groups: the volume of remaining tooth structure, the surface area of the access opening at the occlusal, and remaining dentin thickness at the CEJ. Results: The remaining dentin thickness (percent loss) was not significantly larger for TEA than for CDEA. The surface area (post-treatment) was significantly larger for TEA than for CDEA, and volume (percent loss) was significantly larger for TEA than for CDEA. Conclusion: The use of the CBCT and Dolphin 3D imaging provided an accurate and more conservative CDEA with the guide of an acrylic stent.
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    Influence of exposure protocol, voxel size, and artifact removal algorithm on the trueness of segmentation utilizing an artificial-intelligence-based system
    (Wiley, 2024-07) Alrashed, Safa; Dutra, Vinicius; Chu, Tien-Min G.; Yang, Chao-Chieh; Lin, Wei-Shao; Prosthodontics, School of Dentistry
    Purpose To evaluate the effects of exposure protocol, voxel sizes, and artifact removal algorithms on the trueness of segmentation in various mandible regions using an artificial intelligence (AI)-based system. Materials and methods Eleven dry human mandibles were scanned using a cone beam computed tomography (CBCT) scanner under differing exposure protocols (standard and ultra-low), voxel sizes (0.15 mm, 0.3 mm, and 0.45 mm), and with or without artifact removal algorithm. The resulting datasets were segmented using an AI-based system, exported as 3D models, and compared to reference files derived from a white-light laboratory scanner. Deviation measurement was performed using a computer-aided design (CAD) program and recorded as root mean square (RMS). The RMS values were used as a representation of the trueness of the AI-segmented 3D models. A 4-way ANOVA was used to assess the impact of voxel size, exposure protocol, artifact removal algorithm, and location on RMS values (α = 0.05). Results Significant effects were found with voxel size (p < 0.001) and location (p < 0.001), but not with exposure protocol (p = 0.259) or artifact removal algorithm (p = 0.752). Standard exposure groups had significantly lower RMS values than the ultra-low exposure groups in the mandible body with 0.3 mm (p = 0.014) or 0.45 mm (p < 0.001) voxel sizes, the symphysis with a 0.45 mm voxel size (p = 0.011), and the whole mandible with a 0.45 mm voxel size (p = 0.001). Exposure protocol did not affect RMS values at teeth and alveolar bone (p = 0.544), mandible angles (p = 0.380), condyles (p = 0.114), and coronoids (p = 0.806) locations. Conclusion This study informs optimal exposure protocol and voxel size choices in CBCT imaging for true AI-based automatic segmentation with minimal radiation. The artifact removal algorithm did not influence the trueness of AI segmentation. When using an ultra-low exposure protocol to minimize patient radiation exposure in AI segmentations, a voxel size of 0.15 mm is recommended, while a voxel size of 0.45 mm should be avoided.
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    Testing Adaptations of Cognitive-Behavioral Conjoint Therapy for PTSD: A Randomized Controlled Pilot Study with Veterans
    (APA, 2021-06) Davis, Louanne W.; Luedtke, Brandi L.; Monson, Candice; Siegel, Alysia; Daggy, Joanne K.; Yang, Ziyi; Bair, Matthew J.; Brustuen, Beth; Ertl, Michelle; Psychiatry, School of Medicine
    Iraq and Afghanistan Veterans with posttraumatic stress disorder (PTSD) have well-documented relationship problems and many wish to include their intimate partners in treatment. This pilot study randomly assigned 46 couples (Veterans with clinician-administered PTSD scale confirmed PTSD diagnosis and their intimate partners) to one of two groups. The treatment group received a modified mindfulness-based version of cognitive-behavioral conjoint therapy for PTSD (CBCT; Monson & Fredman, 2012) that included all three phases of the mindfulness-based cognitive behavioral conjoint therapy (MB-CBCT). The control group received a modified version of CBCT that included communication skills training from Phases 1 and 2 of CBCT (CBCT-CS) without PTSD-specific content. Modified CBCT Phases 1 and 2 content was delivered to both groups during weekend retreats in multicouple group sessions. The postretreat protocol for MB-CBCT included nine individual couple sessions: a transition session following the retreat, and CBCT Phase 3. For CBCT-CS, two additional monthly multicouple group sessions reviewed communication skills. No statistically significant pre- to posttreatment differences were detected for primary outcomes between groups: Clinician-Administered PTSD Scale for Veterans (mean change difference, −1.4, 95% CI [−16.0 to 13.2]); Dyadic Adjustment Scale for Veterans (mean change difference, −1.0, 95% CI [−13.2 to 11.2]); and Dyadic Adjustment Scale for Partners (mean change difference, −0.4, 95% CI [−8.9 to 8.1]). However, within group pre- to posttreatment effect sizes were medium to large for both MB-CBCT and CBCT-CS on all three primary outcomes. Findings suggest that Veterans returning from recent conflicts and their partners may benefit from both modifications of CBCT.