Correlation between the presence of tonsilloliths and the bone defects by periodontitis on imaging analysis: a pilot study.

Background: Very recently, a significant relationship between tonsilloliths and dental plaque-related pathologies was reported using digital panoramic radiographs. Their dynamics over time suggest that tonsilloliths may be in a permanently active phase that functions to remove foreign matter. The aim of the study was to evaluate the relationship between the occurrence of tonsilloliths and the extent of periodontitis.

Visualization of Peripheral Blood Vessels on the Lingual Aspect of the Mandible Using a Balanced Steady-State Free-Precession Sequence with a Time-Spatial Labeling Inversion Pulse: Usefulness for Prevention of Severe Complications of Dental Implantation.

The aim of this study was to evaluate whether a balanced steady-state free-precession (SSFP) sequence with a time-spatial labeling inversion pulse (time-SLIP) without contrast medium could elucidate branches of the lingual and facial arteries on the lingual aspect of the mandible as a potential technique for preventing severe complications in dental implantation surgery. In this study, magnetic resonance angiography (MRA) using SSFP with a time-SLIP was evaluated in 40 subjects. The outline and course of branches of the lingual and facial arteries near the mandible were assessed clinically in the same subjects against contrast-enhanced computed tomography (CT) images as the gold standard.

Imaging characteristics of the gubernaculum tracts in successional teeth related to deciduous fused teeth on computed tomography.

The purpose of this study was to elucidate the imaging characteristics of the gubernaculum tracts in successional teeth related to fused deciduous teeth on computed tomography. The imaging findings of 15 gubernaculum tracts in successional teeth related to fused deciduous teeth were retrospectively analyzed using cone-beam computed tomography or multidetector computed tomography. In cases without a congenitally defected successor, the two gubernaculum tracts of two successional teeth related to fused deciduous teeth were fused into one.

Overview of Radiological Studies on Visualization of Gubernaculum Tracts of Permanent Teeth.

The eruption pathway from the dental follicle to the gingiva for permanent teeth is known as the gubernaculum tract (GT), a physiologic structure thought to play a role in tooth eruption. Cone beam computed tomography and multi-detector computed tomography have recently been used to visualize the GT, with the results indicating that this structure might be related to the normal eruption of teeth. By contrast, curved and/or constricted GTs may lead to abnormal tooth eruption.

Imaging peculiarities of gubernaculum tracts in molars as accessional teeth on CT.

Objectives: The shapes of gubernaculum tracts (GTs) in molars as accessional teeth remain unidentified. To elucidate imaging peculiarities of GTs in molars with aging on multidetector-row computed tomography (MDCT).

Material And Methods: This retrospective study was conducted using CT images, including maxillary and mandibular molars, with no abnormal findings from 239 patients.

Changes in tonsillolith characteristics detected in a follow-up CT study.

Background: Tonsilloliths are related clinically to halitosis and tonsillar abscess. However, the dynamics of tonsilloliths over time are unknown. The aim of the study was to evaluate change in the characteristics of tonsilloliths in a time-dependent fashion by follow-up computed tomography (CT).

Advocacy of diagnostic criteria for maxillary incisive canal cysts based on alteration of normal maxillary incisive canals according to aging in Japanese populations.

Background: The purpose of the present study was to describe the CT imaging findings of normal incisive canals and incisive canal cysts and propose cut-off values to differentiate between them.

Methods: A total of 220 normal subjects and 40 patients with incisive canal cysts on multi-detector row computed tomography (MDCT) were retrospectively analyzed. The shapes, sizes, anatomic variations, Hounsfield scale values, and so on of maxillary incisive canals and the sizes and Hounsfield scale values of maxillary incisive canal cysts were analyzed.

Can the lower rate of CT- or MRI-related adverse drug reactions to contrast media due to stricter limitations on patients undergoing contrast-enhanced CT or MRI?

Objective: The aim of this study was to examine whether a decreased occurrence rate of adverse drug reactions (ADRs) to contrast media in contrast-enhanced CT and MRI was attributable to appropriate criteria for patients with some diseases. A secondary aim was to elucidate safety profiles for contrast media and factors influencing the occurrence of ADRs.

Methods: Clinical data of patients who underwent contrast-enhanced CT (5576 cases) or MRI (3357 cases) were retrospectively analyzed to evaluate rates of ADRs to contrast media, symptoms of ADRs, treatments for ADRs, and differences in medical history, blood test results, and other factors between patients with and without ADRs in a dental hospital.

Evaluation of velopharyngeal function using high-speed cine-magnetic resonance imaging based on T2-weighted sequences: a preliminary study.

The objective was to introduce a new technique for visualizing the three-dimensional (3D) movements of velopharyngeal-related muscles using high-speed cine-magnetic resonance imaging (MRI) based on T2-weighted sequences. The evaluation of phonation- and water swallowing-related events was performed in 11 healthy subjects. Specifically, whether cine-MRI could precisely visualize normal velopharyngeal function during these two events was examined.

Predicting the therapeutic effect of carbamazepine in trigeminal neuralgia by analysis of neurovascular compression utilizing magnetic resonance cisternography.

The aim of this study was to determine whether the evaluation of neurovascular compression (NVC) using new criteria on magnetic resonance (MR) cisternography improves the prediction of the curative effects of carbamazepine (CBZ) in trigeminal neuralgia (TN). In this study, a new analysis of NVC using MR cisternography was performed retrospectively for 280 patients with clinical signs and symptoms suggesting TN. The new analysis examined whether the site of the NVC was less than 3mm from the edge of the exit point and within the first third of the root entry zone on MR cisternography.

Characteristics of diffusion-weighted images and apparent diffusion coefficients of ranulas and other masses in and around the floor of the mouth.

Objective: The aim of this study was to evaluate the characteristics of diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) values of ranulas. In addition, to elucidate DWI findings and ADC values of other representative masses in and around the floor of the mouth.

Study Design: DWI findings and ADC values in 35 patients with ranulas and 33 patients with other masses were retrospectively reviewed with a central focus on cystic masses or lesions that may have cyst-like components in and around the floor of the mouth based on the diagnosis of each respective disease.

Significance and usefulness of imaging characteristics of gubernaculum tracts for the diagnosis of odontogenic tumors or cysts.

We aimed to determine the significance and usefulness of imaging characteristics of gubernaculum tracts (GT) for the diagnosis of odontogenic tumors or cysts. This was a retrospective analysis of relationships between odontogenic or non-odontogenic tumors or cysts and the GT that were visualized using multi-detector computed tomography (MDCT). The relationship between the size of a mass and expansion of the GT in all odontogenic tumors or cysts to which GTs were contiguous on MDCT, was statistically analyzed.

Functional evaluation of swallowing in patients with tongue cancer before and after surgery using high-speed continuous magnetic resonance imaging based on T2-weighted sequences.

Objectives: The aim of this study was to determine the usefulness of evaluating the function of swallowing before and after surgery in patients with tongue cancer by using T2-weighted sequences of high-speed continuous magnetic resonance imaging (HSCMRI).

Study Design: The imaging findings and related parameters on HSCMRI along with those on routine MRI examinations before and after surgery were examined in 19 patients with tongue cancer. In addition, changes in various parameters during 1 year after surgery were evaluated in 10 patients.

Changes in the distributions of fluorine-18-labelled fluoro-2-deoxy-d-glucose accumulation into tongue-related muscles after dissection in patients with tongue cancer.

Objectives: To elucidate the changes in the distributions of fluorine-18-labelled fluoro-2-deoxy-d-glucose (F-FDG) accumulation in the tongue muscles of patients following four kinds of surgical operations for tongue cancers.

Methods: The changes in the distributions of F-FDG accumulations in the tongue muscles on positron emission tomography (PET)-CT, in association with imaging findings on CT and MRI, were retrospectively analyzed before and after four kinds of surgical operations for 50 patients with tongue cancers.

Results: F-FDG-PET-positive areas appeared at the back of the intrinsic muscles of the tongue after invasive surgery for tongue cancers despite the absence of abnormal findings on CT and MRI.

Alterations in 18F-FDG accumulation into neck-related muscles after neck dissection for patients with oral cancers.

Background: 18F-fluoro-2-deoxy-D-glucose (18F-FDG) accumulations are commonly seen in the neck-related muscles of the surgical and non-surgical sides after surgery with neck dissection (ND) for oral cancers, which leads to radiologists having difficulty in diagnosing the lesions. To examine the alterations in 18F-FDG accumulation in neck-related muscles of patients after ND for oral cancer.

Material And Methods: 18F-FDG accumulations on positron emission tomography (PET)-computed tomography (CT) in neck-related muscles were retrospectively analyzed after surgical dissection of cervical lymph nodes in oral cancers.

A spatial association between odontomas and the gubernaculum tracts.

Objectives: The purpose of this study was to identify the spatial relationship and/or association between odontomas and the gubernaculum tract or the dental sac and the characteristic findings for radiographic diagnosis of odontomas.

Study Design: The visualizations of the odontomas and the gubernaculum tract were retrospectively analyzed using cone beam computed tomography or multidetector computed tomography.

Results: Most of odontomas were within the gubernaculum tract or dental sac of unerupted permanent teeth on computed tomography.

Identification and adjustment of experimental occlusal interference using functional magnetic resonance imaging.

Background: The purpose of this study was to use functional magnetic resonance imaging (fMRI) to quantify changes in brain activity during experimental occlusal interference.

Methods: Fourteen healthy volunteers performed a rhythmical tapping occlusion task with experimental occlusal interference of the right molar tooth at 0 mm (no occlusion), 0.5 mm, and 0.