Purpose: The spatial resolution of cone-beam computed tomography (CBCT) in small fields of view (FOVs) is important for clinical applications. However, it is difficult to measure spatial resolution reliably due to error factors such as noise. The aim of this study was to obtain a modulation transfer function (MTF) more accurately.
Methods: A CBCT apparatus was used with small FOV. An aluminum pipe slightly tilted at an inclination ratio of 77/3 (25.7) was used as the measurement phantom. The MTF was calculated from the edge image of the phantom. The actual oversampling ratio was determined by regression analysis. The experiment was repeated 16 times and the edge-spread function (ESF) was approximated by the least-square method. Furthermore, a low-pass filter (LPF) was applied to eliminate the component at frequencies above the Nyquist frequency. Finally, the MTF was calculated from the pre-processed ESF.
Results: Results showed that pre-processing reduced the noise of the ESF. The MTFs at frequencies of 1.0 and 2.0 LP/mm were 0.59 and 0.18, respectively, in air and 0.52 and 0.16, respectively, in water.
Conclusion: The repeating-edge oversampling method combined with ESF pre-processing improved the accuracy of the MTF under clinically relevant conditions with a phantom.
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http://dx.doi.org/10.2334/josnusd.20-0479 | DOI Listing |
J Contemp Dent Pract
September 2024
RAK College of Dental Sciences, RAK Medical and Health Sciences University, Ras Al Khaimah, United Arab Emirates.
Aim: The aim of this cross-sectional prospective study was to evaluate the bone density changes around the bicortical corticobasal implant placed in the maxilla over 18 months of follow-up using cone-beam computed tomography (CBCT), focusing on the comparison between the anterior and posterior teeth and regions.
Materials And Methods: Thirty-five subjects (20, 53.26%, were males, and 15, 46.
J Contemp Dent Pract
September 2024
Department of Pediatrics Dentistry and Orthodontics, Faculty Odonto-Stomatology, Can Tho University of Medicine and Pharmacy, Can Tho City, Vietnam.
Aim: This study aimed to evaluate the impact of a combination of immediate implant placement with maxillary sinus augmentation (MSA) solely using platelet-rich fibrin (PRF) on guided bone regeneration.
Materials And Methods: An interventional before-after (pre-post) study design was used with 30 dental patients (≥18 years of age; 14 males and 16 females) with initial bone heights ranging between 4 and 6 mm. Following the general check-up and the creation of a study model, the planned implant location demonstrated an external right maxilla diameter of more than 5 mm, thereby validating the cone-beam computed tomography (CBCT) radiograph.
J Oral Rehabil
January 2025
Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ankara Medipol University, Ankara, Turkey.
Background: The foramen of Huschke (FH) and the petrotympanic fissure (PTF) are anatomical structures that can influence temporomandibular joint disorders (TMD) by potentially affecting the movement and function of the mandibular condyle.
Objective: This study investigates the relationship between patients with TMD and the presence of FH and PTF to enhance diagnostic and therapeutic approaches.
Methods: This retrospective study analyzed cone beam computed tomography (CBCT) images from 212 patients.
Sci Rep
January 2025
Office of Research Affairs, Faculty of Dentistry, Chulalongkorn University, Bangkok, 10330, Thailand.
Although the modulus of elasticity of the human periodontal ligament (E) values used in dentistry widely ranged from 0.01 to 175 MPa, the exact E value has not been determined. This study aimed to verify whether and how E values affect the stress distribution over the tooth and periodontium structures, and to determine the appropriate E range.
View Article and Find Full Text PDFInt J Oral Maxillofac Surg
January 2025
Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand. Electronic address:
The aim of this study was to determine the effects of mandibular setback surgery exceeding 5 mm on upper airway and sleep quality in skeletal Class III patients, with comparisons to Class I controls. Sixteen individuals per group were selected based on their ANB angle and surgical need. 2D and 3D airway analyses were conducted.
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