bluuebunny/crossref_metadata_2025_split huggingface dataset:
High-resolution magnetic resonance imaging of squamous cell carcinoma of the tongue: an in vitro study
Authors: Tetsumura A , Yoshino N , Amagasa T , Nagumo K , Okada N , Sasaki T 
Published: October 2024

OBJECTIVES
To determine in vitro the potential of high-resolution MRI for evaluating the depth of tumor invasion of the tongue.

METHODS
Twenty-one resected specimens of squamous cell carcinoma of the tongue were examined on a 1.5T MRI system with a 4 cm surface coil using four different sequences; T1W SE, T2W SE, 3D-FISP and 3D-CISS. The thickness of normal epithelium, tumor depth and width were measured on both MR images and histopathological sections.

RESULTS
The mucosal epithelium, lamina propria and muscles of the tongue were clearly identifiable on MRI. All 21 carcinomas, including three early invasive carcinomas, were clearly demonstrated. A high correlation was found between the values measured by MRI and histopathology for thickness of mucosal epithelium and both depth and width of tumors. There was a good agreement between the T2W SE and the other imaging sequences for measurements of both depth and width of tumors.

CONCLUSION
High-resolution MR imaging appears reliable for the in vitro evaluation of depth of tumor invasion in carcinoma of the tongue.
Radiographic imaging of the mastoid process with conventional tomography: a novel positioning technique
Authors: Kaeppler G , Nestle B , Reinert S 
Published: October 2024

Abstract
The Scanora (Soredex, Helsinki, Finland) is a multimodal unit for maxillofacial imaging combining narrow beam radiography and pluridirectional spiral tomography. We describe a novel technique for imaging the mastoid process based on a modification of the program for coronal tomography of the ear. This technique is of potential clinical value for implant planning and postoperative evaluation in the temporal bone.
Calcification of the stylohyoid complex in Londoners and Hong Kong Chinese
Authors: MacDonald-Jankowski D S 
Published: October 2024

AIM
To compare the prevalence and pattern of calcification of the stylohyoid complex in Hong Kong Chinese with that in London.

METHODS
The panoramic radiographs of two consecutive series of patients attending the primary dental care departments were reviewed, 862 patients in Hong Kong and 800 in London. The morphology of the stylohyoid complex was allocated to one of 12 patterns.

RESULTS
A normal styloid process is significantly more prevalent in Hong Kong (P&lt;0.01). A calcified stylohyoid ligament is significantly more common in London (15.8%) than Hong Kong (3.9%, P&lt;0.01), whereas there is no difference in the prevalence of an elongated styloid process (7.8% in London and 8.6% in Hong Kong). Segmentation was significantly more prevalent in London (P&lt;0.01), whereas symmetry predominated in Hong Kong (P&lt;0.01). Although the mean age of the Hong Kong patients was significantly older than those in London (P&lt;0.001), those with a calcified stylohyoid ligament tended only to be older (0.025&gt;P&gt;0.01). There was no significant difference in age for an elongated styloid process.

CONCLUSION
There are significant differences in the morphology of the stylohyoid complex between London and Hong Kong. A calcified stylohyoid ligament is more prevalent in Londoners.
Sensitometric and clinical evaluation of a new F-speed dental X-ray film
Authors: Syriopoulos K , Velders X L , Sanderink G C , van Der Stelt P F 
Published: October 2024

OBJECTIVE
To compare the sensitometric properties, diagnostic efficacy and image quality of the InSight (F-speed) and Ektaspeed Plus (E-speed) dental X-ray films (Kodak Eastman Co, Rochester, USA).

METHODS
Characteristic curves were constructed, using manual and automatic processing, in order to compare film speed and average gradient. The diagnostic yield was compared by assessment of endodontic file length. Endodontic files, sizes 10 and 15, were placed at the root apex or 1.5 mm short. The exposure time for the InSight films was 20% lower than that of Ektaspeed Plus. Seven dentists rated the position of file tip using a 5-point confidence scale. ROC data were analysed by means of analysis of variance. The null hypothesis was rejected when P&lt;0.05. In order to compare the image quality, 100 pairs of bitewing radiographs of the left (using Ektaspeed Plus) and the right sides (using InSight) of the same patient were made. Four dentists viewed the radiographs and the data were analysed using Kendall's coefficient of concordance.

RESULTS
InSight was faster than Ektaspeed Plus. It was an E-speed film when processed in manual conditions and an F-speed film when processed automatically. The films had comparable average gradient. No significant difference was found in the diagnostic yield using the two films (P=0.648). Two observers showed a significant preference for Ektaspeed Plus.

CONCLUSIONS
The first results of the new InSight film are promising: the exposure time can be reduced by 20% in comparison with Ektaspeed Plus at no detriment to diagnostic efficacy.
An optimized fast protocol for magnetic resonance imaging of the temporomandibular joint
Authors: Honda E , Sasaki T , Simm F C , Maruyama K 
Published: October 2024

OBJECTIVES
To provide a fast protocol for MR imaging of the TMJ with high contrast resolution of both soft tissue and joint fluid.

METHODS
A fast turbo-spin echo (TSE) pulse sequence was developed. The new technique was compared with T1W conventional spin echo (CSE) and T2W TSE sequences in imaging 57 TMJs in 50 patients. Disc location and contour and bone delineation were assessed on three images of each TMJ by one observer. Presence and location of intra-articular fluid were evaluated on both standard T2W and new TSE images. Image quality was scored on a 3 point-scale by one observer.

RESULTS
The net image acquisition time for one plane was 2 min with the new TSE sequence compared with approximately 5-10 min for T1W and 4 min for T2W. The new sequence provided equivalent diagnostic information to a combination of T1W CSE for disc position and contour and bone contour and T2W TSE sequence for joint fluid.

CONCLUSIONS
The examination time for MRI of the TMJ can be considerably reduced with the new fast TSE pulse sequence without compromising image quality.
Continuous radiographic visualization of the mandibular nutrient canals
Authors: Wang P D , Serman N J , Kaufman E 
Published: October 2024

Abstract
The continuous radiographic appearance of the course of mandibular nutrient canals (NC), originating from the incisive branch of the inferior alveolar neurovascular bundle bilaterally, showing anastomoses and terminating in the interdental area of the anterior teeth, is reported for the first time.
Evaluation of a new digital panoramic system: a comparison with film
Authors: Ramesh A , Tyndall D A , Ludlow J B 
Published: October 2024

OBJECTIVES
To evaluate the diagnostic efficacy of the Orthophos DS digital panoramic system (Sirona, Bensheim, Germany) for the detection of dento-alveolar disease in comparison with film.

METHODS
Five patients selected for admission to the School of Dentistry had a panoramic radiograph obtained with the Orthophos Plus (Sirona, Bensheim, Germany) system, a digital panoramic image obtained with the Orthophos DS (Sirona, Bensheim, Germany) system and a full mouth series. The ground truth was determined from the full mouth series by a panel of board certified oral and maxillofacial radiologists using the Delphi method. Four observers scored both the film and digital panoramic images for the presence of caries and marginal periodontitis. Results were statistically analysed using ROC analysis and ANOVA.

RESULTS
There was no significant difference (P=0.704) between the two modalities for the detection of caries but there was a significant difference (P=0.015) for the detection of periodontal disease where conventional panoramic film performed better than the digital image.

CONCLUSIONS
Though the conventional film was better than the digital image for the detection of periodontal disease, further studies are needed to determine the clinical significance of this result in relation to the potential advantages of digital technology.
Diagnostic yield of conventional and digital cephalometric images: a human cadaver study
Authors: Gijbels F , Bou Serhal C , Willems G , Bosmans H , Sanderink G , Persoons M , Jacobs R 
Published: October 2024

OBJECTIVES
To compare the clinical efficacy of digital and conventional cephalometric imaging.

METHODS
Conventional and photostimulable phosphor cephalometric radiographs were obtained from three human cadavers at nine different exposure settings. Subjective image quality was assessed by six observers who evaluated six cephalometric landmarks. Organ doses were measured with TLDs and effective doses calculated.

RESULTS
Compared with conventional cephalometric images, digital images had a consistently better subjective image quality for all exposure settings which was significant (P&lt;0.05) for all but two. Organ doses were comparable. Higher kV and lower mAs settings yielded the lowest effective dose, which was highly dependent on the position of the thyroid gland in the beam.

CONCLUSION
Relatively small variations in exposure settings do not influence subjective diagnostic image quality of digital cephalometric radiographs. Higher kV and lower mAs settings have the lowest effective dose and should therefore be preferred.
Root fracture detection: a comparison of direct digital radiography with conventional radiography
Authors: Kositbowornchai S , Nuansakul R , Sikram S , Sinahawattana S , Saengmontri S 
Published: October 2024

OBJECTIVES
To compare the diagnostic potential of direct digital radiography with conventional film for detecting experimental root fractures.

METHODS
Two hundred and one extracted single-rooted human teeth were endodontically instrumented and divided into two groups, a control group of 100 teeth and a fractured group of 101 teeth in which root fractures were produced experimentally. Each tooth was imaged using the paralleling technique with a CCD-based digital system and D-speed film. The images were interpreted by an experienced radiologist without prior knowledge of the distribution of the root fractures. The degree of agreement in detecting root fractures with each imaging system compared with the actual condition was expressed as the kappa value. The difference between the radiographic systems was then assessed by chi(2)-test at the 95% significance level.

RESULTS
There was substantial agreement between the digital system and the actual condition (kappa=0.71; 95% Confidence Interval: 0.62 to 0.80) and close agreement between the film and the actual condition (kappa=0.63; 95% Confidence Interval: 0.53 to 0.74). However, this difference was not significantly different (P=0.2).

CONCLUSIONS
The performance of CCD-based digital radiography in detecting root fractures is similar to film-based radiography.
Osteoradionecrosis of the mandible. Comparison of the effects of external beam irradiation and brachytherapy
Authors: Støre G , Evensen J , Larheim T A 
Published: October 2024

OBJECTIVE
To compare the difference in location and severity of osteoradionecrosis (ORN) of the mandible following either external beam irradiation alone or combined with brachytherapy in the management of orofacial cancer.

METHODS
CT was used to evaluate ORN in relation to the radiation source and field and the site of malignancy in 31 patients with orofacial carcinomas. Twenty-three patients received combined radiotherapy and brachytherapy and eight patients only external radiotherapy. The radiation dose distribution to the mandible was calculated retrospectively.

RESULTS
In the combined radiotherapy group all patients had ORN of the lingual cortex, mostly adjacent to the position of previous iridium implants. Lingual defects were also found in the contralateral mandible in 35% of patients. Defects in the buccal cortex were seen in 30%. In the external radiotherapy group, ORN was found in both buccal and lingual cortices and 50% also in the contralateral mandible. When brachytherapy with iridium implants was used the dose to the buccal cortex was about one-third of that to the lingual cortex. There was no dose gradient between the cortices using external beam irradiation alone.

CONCLUSIONS
Evidence of ORN was found in both groups of irradiation regimens. Thus, the entire irradiated mandible should be considered as a compromised tissue at risk of ORN.
A comparison of diagnostic accuracy of a newly developed photofluorographic panoramic system with conventional panoramic radiography
Authors: Nagata Y 
Published: October 2024

OBJECTIVES
To compare the diagnostic accuracy of a prototype photofluorographic panoramic system with that of a conventional panoramic system.

METHODS
We used 14 human skulls with four artificial apical bone defects in each and 13 clinical cases with 21 periapical lesions. Six dental radiologists and six senior dental students rated the presence of defects on each image on a five-point scale. Receiver Operating Characteristic (ROC) analysis was performed and the area under each curve (Az) was compared as an index of accuracy. Statistical significance was set at P&lt;0.05.

RESULTS
There were no significant differences between the photofluorographic and the conventional panoramic systems (P=0.074) in detecting artificial apical defects. However, there were significant differences (P=0.03) in detecting natural defects.

CONCLUSIONS
The diagnostic accuracy of the prototype photofluorographic panoramic system appears comparable with that of the conventional panoramic system. However, variability may arise from the observers' diagnostic experience and training.
Analysis of fractal dimensions of rat bones from film and digital images
Authors: Pornprasertsuk S , Ludlow J B , Webber R L , Tyndall D A , Yamauchi M 
Published: October 2024

OBJECTIVES
(1) To compare the effect of two different intra-oral image receptors on estimates of fractal dimension; and (2) to determine the variations in fractal dimensions between the femur, tibia and humerus of the rat and between their proximal, middle and distal regions.

METHODS
The left femur, tibia and humerus from 24 4-6-month-old Sprague-Dawley rats were radiographed using intra-oral film and a charge-coupled device (CCD). Films were digitized at a pixel density comparable to the CCD using a flat-bed scanner. Square regions of interest were selected from proximal, middle, and distal regions of each bone. Fractal dimensions were estimated from the slope of regression lines fitted to plots of log power against log spatial frequency.

RESULTS
The fractal dimensions estimates from digitized films were significantly greater than those produced from the CCD (P=0.0008). Estimated fractal dimensions of three types of bone were not significantly different (P=0.0544); however, the three regions of bones were significantly different (P=0.0239). The fractal dimensions estimated from radiographs of the proximal and distal regions of the bones were lower than comparable estimates obtained from the middle region.

CONCLUSIONS
Different types of image receptors significantly affect estimates of fractal dimension. There was no difference in the fractal dimensions of the different bones but the three regions differed significantly.
The relationship of primary tumor thickness in carcinoma of the tongue to subsequent lymph node metastasis
Authors: Hayashi T , Ito J , Taira S , Katsura K 
Published: October 2024

OBJECTIVES
To study whether primary tumor thickness of stage I/II tongue carcinoma provides information about subsequent lymph node metastasis.

METHODS
Twenty consecutive patients with T1N0M0 or T2N0M0 tongue carcinoma were studied. Primary tumor thickness was measured with post-contrast helical computed tomography or intra-oral sonography. Cervical lymph nodes were evaluated periodically with sonography at intervals of 2-4 weeks. Sensitivity, specificity and accuracy for subsequent metastasis was calculated.

RESULTS
Positive sonographic findings appeared in nine nodes of nine patients during this follow-up period. Eleven patients underwent neck dissections, and nine had histopathologically positive nodes. Nine patients had no sonographic findings of metastasis during a minimum follow-up period of 20 months. Primary tumor thickness varied from 3-16 mm. Using 5 mm as a cut-off thickness, the sensitivity, specificity and accuracy for subsequent lymph node metastasis were 64, 100 and 75% respectively.

CONCLUSIONS
Patients with stage I/II tongue carcinoma which is more than 5 mm thick are more likely to develop lymph node metastasis.
Diagnostic accuracy of computed tomography for cervical metastases at different anatomical levels in carcinoma of the tongue
Authors: Ogura I , Kurabayashi T , Amagasa T , Sasaki T 
Published: October 2024

OBJECTIVES
To evaluate the variation in diagnostic accuracy of CT in the assessment of cervical lymph node metastases from tongue carcinoma at different anatomical levels.

METHODS
Sixty-one patients with squamous cell carcinoma of the tongue who underwent radical neck dissection were included in this study. The CT and histopathological findings at nodal levels I-V were compared for the presence or absence of lymph node metastases. Sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) of CT were evaluated for each nodal level.

RESULTS
The sensitivity of CT was: level I, 85%; level II, 77.8%; level III, 53.3%; level IV, 66.7% and level V, 25%. There was a significant difference in the sensitivity between the level I-II group (80.9%) and level III-V group (53.6%) (P=0.012). There was no significant difference in the specificity, NPV, and PPV between the two groups.

CONCLUSIONS
The sensitivity of CT in detecting cervical lymph node metastases was significantly smaller at levels III-V than at levels I-II.
Diagnostic value of dynamic magnetic resonance imaging for salivary gland diseases: a preliminary study
Authors: Suenaga S , Indo H , Noikura T 
Published: October 2024

OBJECTIVES
To determine the diagnostic value of dynamic MR imaging for the differentiation between benign tumours, malignant tumours, and inflammatory lesions in the major salivary glands.

METHODS
T1- and T2-weighted spin-echo and dynamic gadolinium-enhanced T1-weighted spin-echo imaging sequences were performed in 27 patients (28 salivary gland lesions). The enhancement curve patterns and tumour margins on dynamic MR imaging were analysed.

RESULTS
All pleomorphic adenomas showed a continuous gradual or rapid increase in the enhancement pattern, whereas other benign tumours had a rapid or gradual enhancement-attenuation pattern. Malignant tumours generally showed a gradual enhancement-attenuation pattern. Inflammatory lesions showed a rapid or gradual enhancement-attenuation pattern. A well-defined margin was observed in all 13 (100%) benign tumours and three of six (50%) malignant tumours.

CONCLUSIONS
Our study suggests that dynamic curve patterns and tumour margin appearance may help to differentiate between benign tumours, malignant tumours and inflammatory lesions.
Organ doses and subjective image quality of indirect digital panoramic radiography
Authors: Gijbels F , Sanderink G , Bou Serhal C , Pauwels H , Jacobs R 
Published: October 2024

OBJECTIVES
To determine if slight variations in exposure will affect diagnostic image quality and absorbed radiation doses for digital and analogue panoramic radiography.

METHODS
Thermoluminescent dosimeters were placed in the thyroid gland, eyes, submandibular glands, parotid glands and skin of two human cadaver heads. Three different exposure settings were used: 70 kV, 120 mAs; 77 kV, 75 mAs; and 81 kV, 60 mAs. Subjective image quality was assessed using a phantom head. Storage phosphor (SP) images were printed on film and both analogue and SP images were assessed for their subjective image quality on a five-point rating scale. The results were statistically analysed using logistic regression analysis and chi(2) tests.

RESULTS
Highest organ doses were measured for the submandibular glands, followed by the parotid glands. Salivary gland doses tended to be higher at lower kV settings. Image quality was not statistically different for the different exposure settings. Imaging technique did not seem to influence diagnostic image quality, except for the periapical status of upper premolars where SP was better. The main reason for any differences appeared to be interobserver variation.

CONCLUSIONS
Analogue and SP panoramic radiography performed equally well for subjective diagnostic image quality. No significant differences could be found at the exposure settings used in this study. Radiation doses were highest for the salivary glands, especially at lower kV settings.
Management of oral and maxillofacial radiology clinics in Taiwan's dental schools
Authors: Chen S K , Chien H H , Lin L 
Published: October 2024

OBJECTIVES
To investigate management of Taiwanese dental school Oral and Maxillofacial Radiology (OMFR) clinics and to suggest alternative management strategies.

METHODS
A management questionnaire was designed for the faculty responsible for teaching the Oral and Maxillofacial Radiology curriculum.

RESULTS
Data from all seven Taiwanese schools indicated inadequate supervision of the prescription of radiological examinations in the absence of guidelines. Most schools are understaffed and not properly equipped. There is a significant shortage of trained dentists in the field of OMFR. In some schools no dentist is involved in the management of OMFR clinics. Some aspects of quality assurance procedures should be enhanced. An average of 21.4% of films were reported lost, with the highest rate at 40%, demonstrating serious problems in image archiving. Clinician satisfaction with clinic management averaged 74.3%, with a minimum of 50%.

CONCLUSION
A set of standards is recommended by the Taiwanese OMFR Association after reviewing the survey findings. Prescription for OMFR examination should be supervised by licensed clinicians, and there is a need for guidelines. Trained and dedicated personnel should be assigned for the management of OMFR clinics. More quality assurance procedures should be performed. A computer-based image archiving system is desirable.
Influence of the number of basis images and projection array on caries detection using tuned aperture computed tomography (TACT).
Authors: Abreu M , Tyndall D A , Ludlow J B , Nortjé C J 
Published: October 2024

OBJECTIVES
to determine if the number of basis images and spatial distribution of the projection array used for TACT slice generation influence observer performance in caries detection.

METHODS
In the first experiment, 2, 4, 8 and 12 basis projections of each of 40 teeth were acquired using a CMOS digital radiography sensor. Projections were distributed radially in space using a 20 degree angular disparity. TACT slices were generated from the four subgroups of images, presented to eight observers, and viewed on a high-resolution monitor. Observers scored the presence/absence of caries using a 5-point confidence scale. Gold standard was histological examination of tooth sections. ROC curves measured observer diagnostic performance. ANOVA tested for significant differences between observers and experimental conditions. In the second experiment, the number of basis projections judged to be satisfactory for TACT slice generation was used. Horizontal and vertical linear arrays of projections were compared to the circular projection array.

RESULTS
There was a statistically significant difference between the numbers of basis projections in the detection of both occlusal (P=0.006) and proximal caries (P=0.005). No significant difference was found between projection arrays in the detection of either occlusal (P=0.065) or proximal (P=0.515) caries.

CONCLUSIONS
The number of TACT basis projections significantly influences caries detection. Eight or more images should be used. Either linear-vertical, linear-horizontal or circular arrays of basis projections may be used for TACT slice generation in caries detection tasks.