Vertical magnification correction in vertical dual-exposure panoramic radiography.

Purpose: To clarify the magnification error caused by the degree of tilt of the incisor and the elevation of the X-ray focus position, and the verification effect of magnification correction when performing vertical dual-exposure panoramic radiography.

Methods: Panoramic radiographic images of a phantom embedding 26 steel balls were taken at different heights (0, 5, 10, 15, and 20 mm) and tilt angles (0°, 10°, 20°, and 30°) to evaluate vertical magnification in each condition. Error and correlation coefficients in the vertical magnifications were calculated between the measured and theoretical magnification values.

Reduction of cervical vertebra ghost images in panoramic radiography using vertical dual exposure.

Purpose: To evaluate the image quality of vertical dual-exposure panoramic radiography (PR), which merges two PR images taken at different focus heights to reduce ghost images of cervical vertebrae (CV) and intervertebral spaces (IVS) in the incisor region.

Methods: PR images of an aluminum block, a CV phantom and a human head phantom were taken at 0 mm and merged with and subtracted from PR images taken at other heights (0, 5, 10, 15, and 20 mm) to create new images, e.g.

Correction of intraoral radiography with dual imaging plates using enlargement of the horizontal direction with division into 12 blocks.

Purpose: The dual imaging plate (DIP) method, which synthesizes intraoral radiographs from a front imaging plate (FIP) and a back imaging plate (BIP), produces adequate image quality and allows the radiation dose to be reduced. However, there are slight errors in superimposition and alignment between the FIP and BIP. The aim of this study was to establish positional correction in the DIP method and evaluate the effect.

Reduction of scratch or dirt artifacts on intraoral radiographs using dual imaging plates in image processing.

Objectives: Artifacts including scratches and dirt artifacts on the digital intraoral radiographs finally contribute to making inaccurate diagnoses. The aim of this study was to reduce the incidence of artifacts using dual imaging plates (DIPs) in imaging processing.

Methods: Conventional X-rays were taken of a porcine mandible embedded in acrylic resin using a DIP which consists of a front IP (FIP) and a back IP (BIP) with some scratches and dirt.

Infective Endocarditis With Secondary Headache: A Case Report.

Secondary headache is a symptom of an underlying disease. Infective endocarditis (IE) is a serious infection of the heart tissue. Herein, we present a rare case of IE, with a secondary headache.

Preliminary evaluation of dual imaging plate intraoral radiography.

Purpose: This study evaluated the contrast-to-noise ratio (CNR), spatial resolution, and subjective quality of dual imaging plates (DIP) intraoral radiography.

Methods: The DIP and conventional single IP (CSIP) methods both used YCR DT-1 imaging plates (Yoshida Co.).

Evaluation of cone-beam computed tomography over a small field of view in a water bath based on the modulation transfer function with repeating-edge oversampling.

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.

Morphological characteristics of interalveolar septum and mandible in BMAL1 gene knockout mice.

Purpose: Circadian rhythm is associated with the pathogenesis of systemic disease and bone mineral metabolism. This study aimed to radiographically evaluate morphological characteristics of the interalveolar septum in circadian rhythm deficient animals.

Methods: Heads of 10 brain and muscle arnt-like protein-1 (BMAL1)-knockout (KO) mice and 10 wild-type mice sacrificed at 36 weeks were imaged using micro-computed tomography.

Use of experimental phantoms to determine the accuracy and reliability of mandibular cortical width measurements by panoramic radiography and cone-beam computed tomography.

The present study used an aluminum phantom to calculate accurate vertical magnification values around the mental foramen on panoramic radiography (PR) and compared corrected PR (Cor-PR) thickness measurements of the aluminum phantom and mandibular cortical width (MCW) of the human head with cone-beam computed tomography (CBCT) measurements at two fields of view (FOVs). The calculated vertical magnification value for PR around the mental foramen was 1.37.

Newly developed mastication activity reduction procedure rapidly induces abnormal atrophic change of the mandibular condyle in young and elder experimental animal models.

This study was performed to develop a new rat model of reduced masticatory activity in order to assess the effect of this reduction on the morphology of the temporomandibular joint (TMJ) over time. Female rats were used, and ovariectomy was performed to simulate aged/postmenopausal status. Twenty-four SD rats aged 6 weeks were divided into four groups: ovariectomy/sham procedure (Ov/S); ovariectomy/reduced masticatory activity (Ov/RMA); non-Ov/S (NO/S); and non-Ov/RMA (NO/RMA).

Diagnostic reliability of 3.0-T MRI for detecting osseous abnormalities of the temporomandibular joint.

We compared the diagnostic reliability of 3.0-T magnetic resonance imaging (MRI) for detection of osseous abnormalities of the temporomandibular joint (TMJ) with that of the gold standard, cone-beam computed tomography (CBCT). Fifty-six TMJs were imaged with CBCT and MRI, and images of condyles and fossae were independently assessed for the presence of osseous abnormalities.

Diverse calcification patterns of ameloblastic fibro-odontoma on radiographic examination.

The occurrence of ameloblastic fibro-odontoma (AFO) in the oral region is unusual and accounts for 1-3% of all odontogenic tumors. AFO presents mixed radiopaque patterns within the lesion with diverse findings; therefore, it is important to compare this tumor with other odontogenic tumors that radiographically present with calcified bodies. Herein, we observed the calcification patterns within the lesion in seven AFO cases (five males, two females; mean age, 8.

Retrospective magnetic resonance imaging study of risk factors associated with sideways disk displacement of the temporomandibular joint.

As part of our ongoing investigation of risk and predictive factors associated with temporomandibular disorders, we used magnetic resonance imaging (MRI) to identify risk factors for sideways disk displacement of the temporomandibular joint in 26 patients with MRI-confirmed unilateral pure sideways disk displacement (medial or lateral disk displacement) and normal positioning of the contralateral temporomandibular joint. Coronal morphologic harmonization between the condyle and fossa, angle between the axis of the ramus and condyle, and angle between the lateral pterygoid muscle (LPM) and condyle were evaluated. Only angle of the LPM related to the condyle was significantly correlated with mediolateral disk position; the angles of joints with medial, normal, and lateral disk positions were 70.

Osteochondroma of the coronoid process of the mandible.

We describe a rare case of osteochondroma of the coronoid process of mandible accompanied by severe trismus in a 14-year-old Japanese boy. The patient had initially been diagnosed as having internal derangement of the temporomandibular joint (TMJ), and conservative treatment had failed to improve the symptoms. Despite extremely limited TMJ movement, panoramic radiography revealed no abnormality, but magnetic resonance imaging suggested internal derangement of the left TMJ.

Comparative analysis of the gonial angle on lateral cephalometric radiographs and panoramic radiographs.

We measured the gonial angle (GA) on panoramic radiography (PR) and analyzed the correlation between the GA on PR and lateral cephalometric radiography (LCR). In total, 49 PR films and LCR films from dentate young adults were evaluated. Orthodontists plotted four points (articulare, menton, posterior gonion, and lower gonion) on the PR and carefully traced them.

Assessment of quality and interpretation of panoramic radiographs obtained in the Lao People's Democratic Republic as part of a teleradiology collaboration with Japan.

As part of quality assessment of a teleradiology program we evaluated the validity of patient information received, the quality of panoramic radiography imaging in Laos, and the ability of a Laotian radiologist to detect temporomandibular joint abnormalities. The amount of patient information gathered from 2,021 scans of panoramic radiographs was evaluated by triage before image diagnosis. Among the radiographs from 2,021 patients, primary triage indicated that there was insufficient information for 794 (39.

Involvement of trigeminal transition zone and laminated subnucleus caudalis in masseter muscle hypersensitivity associated with tooth inflammation.

A rat model of pulpitis/periapical periodontitis was used to study mechanisms underlying extraterritorial enhancement of masseter response associated with tooth inflammation. Periapical bone loss gradually increased and peaked at 6 weeks after complete Freund's adjuvant (CFA) application to the upper molar tooth pulp (M1). On day 3, the number of Fos-immunoreactive (IR) cells was significantly larger in M1 CFA rats compared with M1 vehicle (veh) rats in the trigeminal subnucleus interpolaris/caudalis transition zone (Vi/Vc).

Discrepancy of coronal morphology between mandibular condyle and fossa is related to pathogenesis of anterior disk displacement of the temporomandibular joint.

Objective: To evaluate whether morphological discrepancy between the mandibular condyle and fossa of the temporomandibular joint (TMJ) is related to disk displacement on magnetic resonance imaging (MRI).

Study Design: This study included 61 patients with unilateral internal derangement based on both MRI and clinical examination. Coronal morphologies of the condyle and fossa were divided into four groups based on Öberg's classification.

Asymptomatic radiopaque lesions of the jaws: a radiographic study using cone-beam computed tomography.

Panoramic radiography and cone-beam computed tomography (CT) were used to analyze asymptomatic radiopaque lesions in the jaw bones and determine the diagnostic relevance of the lesions based on their relationships to teeth and site of origin. One hundred radiopaque lesions detected between 1998 and 2002 were examined by both panoramic radiography and cone-beam CT. On the basis of panoramic radiographs, the region was classified as periapical, body, or edentulous, and the site was classified as molar or premolar.

An image-guided technique for puncture of the superior temporomandibular joint cavity: clinical comparison with the conventional puncture technique.

Objective: The objective of this study was to compare an image-guided puncture technique (IGPT) with conventional puncture technique (CPT) with respect to accuracy of needle entry, maximal mouth opening, and pain in pumping manipulation treatment of internal derangement of the temporomandibular joint (TMJ).

Study Design: The subjects comprised 178 patients with internal derangement of the TMJ with closed lock. Treatment was provided using CPT in 102 cases and IGPT in 76 cases.