bluuebunny/crossref_metadata_2025_split huggingface dataset:
Correlation between quantitative salivary gland scintigraphy and salivary secretion rates in children and young adults treated for hematological, malignant and metabolic diseases
Authors: Bågesund M , Richter S , Agren B , Dahllöf G 
Published: October 2024

OBJECTIVES
To study the correlation between whole salivary secretion rates and different variables from the radionuclide time-activity curve and to determine a reliable region for background correction in salivary gland scintigraphy.

METHODS
Salivary gland scintigraphy (SGS) was performed before bone marrow transplantation or more than 4 years later in 23 patients aged 13.5 (s.d. 4.9) years. Unstimulated and stimulated whole salivary secretion rates were measured before SGS. Six different methods for background correction were evaluated.

RESULTS
The unstimulated secretion rate was significantly correlated (P &lt; 0.05) with the percentage stimulated secretion (S) and reaccumulation-slope (RS) after stimulation. The stimulated secretion rate was significantly correlated with RS, S and down-slope (DS). The temporal region above the parotid glands and the area above the thyroid gland was used for subtraction of background radiation for the parotid and submandibular glands respectively showed a strong correlation between repeated measurements of the variables analysed. The mean maximum uptake was 0.73-1.34% of total dose injected.

CONCLUSIONS
The salivary scintigraphic variables which correlated more strongly with salivary secretion rates were RS, S and DS. The temporal region above the parotid gland and the area above the thyroid gland can be used reliably for correction background radiation in the analysis of the time-activity curve in SGS of the parotid and submandibular glands respectively.
Comparison of observer performance in determining the position of endodontic files with physical measures in the evaluation of dental X-ray imaging systems
Authors: Vandre R H , Pajak J C , Abdel-Nabi H , Farman T T , Farman A G 
Published: October 2024

OBJECTIVE
To examine the feasibility of substituting observers determining the accuracy of endodontic measurements for measurements of physical qualities in comparison of digital imaging systems.

METHODS
Sensors from six digital imaging systems were compared for signal-to-noise ratio (SNR), modulation transfer function (MTF) and detective quantum efficiency (DQE). A total of 45 canals in teeth from human cadavers were instrumented to their apical foramina. Endodontic files, ranging in size from size 8 to size 20, were glued in place at random distances from the apical foramina spanning a range of +/- 3 mm. The teeth were imaged with the six digital systems and dental X-ray film. Fifteen dentists independently measured the distance from the end of the file to the apical foramen. Results were expressed as the measurement error. Measurement error was compared to SNR, MTF and DQE for each digital system.

RESULTS
CDR (Schick, New York, NY, USA), Digora (Sordex, Helsinki, Finland) and Dexis (Provision Dental Systems, Palo Alto, CA, USA) produced the highest SNR values followed closely by RVG-4 (Trophy, Croissy-Beavborg, France). Sens-A-Ray (Dent-X/Regam Medical Systems, Sundsvall, Sweden), Dexis and the RVG-4 produced the best MTF results. Dexis had the greatest DQE. The mean measurement errors (in mm) were: Film 0.65, Dexis 0.69, CDR 0.71, RVG-4 0.74, Digora 0.89, Sens-A-Ray 0.97, and Visualix-2 (Gendex, Monza, Italy) 0.98.

CONCLUSIONS
Digital systems closely approximate film in their accuracy when used for endodontic measurement providing that the assessment instruments have similar resolving power. DQE was the best physical predictor of system accuracy when compared with endodontic length measurements. MTF and SNR alone did not accurately predict observer precision.
Basic study of the measurement of bone mineral content of cortical and cancellous bone of the mandible by computed tomography
Authors: Iwashita Y 
Published: October 2024

OBJECTIVES
To develop an algorithm for automatic separation of cortical from cancellous bone in the mandible and for measuring mandibular bone mineral content (BMC).

METHODS
A dried mandible was scanned together with a reference phantom by spiral CT. A new algorithm was developed specifically for the mandible and cross-sectional images reconstructed in the buccolingual plane. The cortical bone was extracted with a threshold of 80% of the peak height in the line-scan profile and the cancellous bone extracted separately. The volume and BMC were estimated. Images of cortical and cancellous bone were displayed in a plane approximating the orientation used for dental radiography and BMC expressed as aluminium-equivalents (Al-eqs).

RESULTS
The ratio of cortical to cancellous bone by volume was 22:78, and the ratio of the BMC 60:40. Comparison of BMC from reconstructed CT with Al-eqs showed good correlation but was 1.5 times higher with CT.

CONCLUSIONS
It is possible to separate cancellous from cortical bone automatically from CT images and to measure the BMC.
The prevalence of radiographically evident mandibular tori in the University of Iowa dental patients
Authors: Ruprecht A , Hellstein J , Bobinet K , Mattinson C 
Published: October 2024

OBJECTIVES
To evaluate the radiographic prevalence of mandibular tori and to determine the attributes which make tori radiographically evident.

METHODS
The prevalence of mandibular tori was determined from 1600 radiographic surveys of patients attending the College of Dentistry, University of Iowa, 200 for each decade of life from the first to the eighth. Dry skulls were evaluated at the National Museum of Natural History. Mandibular tori were measured, classified and radiographed to correlate the radiographic findings with the physical characteristics.

RESULTS
Overall, 16.9% of the patient population had radiographically detectable mandibular tori with some cohorts within the population as high as 33%. Lobulated tori extending 4 mm or more mediolaterally were radiographically detectable.

CONCLUSIONS
This study revealed one of the higher prevalence rates of mandibular tori in the literature for a population within the United States. Radiographic threshold analysis suggests that this group of Iowans has a high percentage of medium to large discretely lobulated tori.
A new method for the radiological investigation of residual ridge resorption in the maxilla
Authors: Kreisler M , Schulze R , Schalldach F , d'Hoedt B , Behneke A , Behneke N 
Published: October 2024

OBJECTIVES
To develop a new method for assessing residual ridge resorption in the edentulous maxilla.

METHODS
Defined experimental and reference areas in the maxilla were drawn on transparent film laid over a panoramic radiograph and digitized. Bone areas were measured with an integrated planimetry program and expressed as a ratio R. The effect of positioning errors on reliability of the method was investigated on dry skulls. The correlation between the change in ratio and actual bone loss was examined by progressively reducing the height of an artificial residual ridge on one skull.

RESULTS
The coefficient of variation for the absolute ratio in different head positions was &lt; 0.05 and its correlation coefficient of the change in R and the degree of resorption was r2 &gt; or = 98.3%, P = 0.0001.

CONCLUSIONS
Comparison of the experimental area with the reference area on serial panoramic radiographs appears suitable for the assessment of residual resorption in the maxilla.
Radiological and clinical features of calcifying epithelial odontogenic tumour
Authors: Kaplan I , Buchner A , Calderon S , Kaffe I 
Published: October 2024

OBJECTIVES
To analyse systematically the radiographic features of the calcifying epithelial odontogenic tumour (CEOT).

METHOD
Clinical and radiological features of 67 cases of CEOT (four new and 63 from the literature) were analysed.

RESULTS
There were 27 (41%) males and 39 (59%) females with a male-to-female ratio of 1 : 1.5. Age ranged from 13 - 77 years (mean 43.5 years), with a peak in the fourth and fifth decades. The mandible was involved in 74% of the cases and 69% of all lesions were in the posterior area. The mixed radiolucent-radiopaque pattern was the most frequent (65%), with 32% radiolucent and 3% radiopaque. Coronal clustering of the radiopaque material was found in 12% and in one case, a 'driven snow' pattern of the radiopaque material was clearly recognizable. Lesions were unilocular in 58%, multilocular in 27% and not loculated in 15%. The unilocular type was more frequent in the maxilla than in the mandible. Borders were well defined and corticated in 20%, defined but not corticated in 59% and diffuse in 21%. Sixty per cent were associated with impacted teeth. Lesions larger than 3 cm tended to be more frequent in the mandible, mixed radiolucent-radiopaque and to have a higher proportion of diffuse borders than the smaller lesions.

CONCLUSION
Radiographic features which have been considered characteristic of CEOT, coronal clustering and 'driven snow' patterns, are seen in only a small percentage of cases.
Advanced imaging in renal osteodystrophy of the oral and maxillofacial region
Authors: Asaumi J , Aiga H , Hisatomi M , Shigehara H , Kishi K 
Published: October 2024

Abstract
Magnetic resonance imaging and computed tomography was performed in one and two patients, respectively, with renal osteodystrophy (ROD). Conventional radiographs clearly depicted the characteristics of ROD of the oral and maxillofacial region. CT and MRI did not add any more information.
Comparison of computed tomography with conventional radiography for midfacial fractures.
Authors: Tanrikulu R , Erol B 
Published: October 2024

OBJECTIVE
To compare the clinical effectiveness of computed tomography (CT) with conventional radiography in midfacial fractures.

METHODS
The conventional radiographs (CM) and CT scans of 40 consecutive patients with complex midfacial fractures were assessed independently by two examiners. The number and site of fractures of the orbit, zygoma and maxilla were compared by the Wilcoxon Matched Pairs Signed Rank test. The best method for classification of the fracture was determined.

RESULTS
Coronal CT (CCT) proved superior in the diagnosis of orbital fractures (P&lt;0.001). There was no significant difference between any of the imaging methods for fractures of the zygoma. Axial CT (ACT) was the most effective method in imaging of maxillary fractures (ACT-CM; P&lt;0.001, ACT-CCT; P&lt;0.01). CCT was the most useful in classification of orbital and maxillary fracture.

CONCLUSION
CCT is superior to CM for the assessment of complex midface fractures
Variability in measurement of radiomorphometric indices by general dental practitioners
Authors: Devlin C V , Horner K , Devlin H 
Published: October 2024

OBJECTIVES
To assess the variability of general dental practitioners (GDPs) in measurement of radiomorphometric indices on panoramic radiographs following basic instruction and to examine whether the variability could be reduced by more individualised instruction.

METHODS
Nine GDPs measured Gonion Index (GI), Antegonion Index (AI), Mental Index (MI) and Mandibular Cortical Index (MCI) on copies of 10 panoramic radiographs following a lecture on osteoporosis and the use of radiomorphometric indices. Their measurements were related to expert-derived measurements of the same copy radiographs. Mean differences and limits of agreement (2x standard deviation of differences) were calculated for quantitative indices (GI, AI, MI) and agreement of GDPs with expert-derived MCI assessments was determined using weighted kappa. Following individualised feedback to GDPs, all measurements were repeated after 2 weeks and the statistical analysis repeated.

RESULTS
There was extensive variation amongst GDPs in measurement of GI, AI and MI and in assessment of MCI. There was a general tendency of GDPs to record thicker mandibular cortices than did the experts. Limits of agreement were wide relative to the mean values of each quantitative index at both readings. Agreement of the GDPs with experts in assessment of MCI was moderate at both readings, but with a wide range in assessment.

CONCLUSIONS
Variability in measuring radiomorphometric indices amongst the GDPs was high and was not predictably improved by individualised instruction. This study casts considerable doubt on the potential value of radiomorphometric indices given their lack of precision.
Detection of simulated internal tooth resorption using conventional radiography and subtraction imaging
Authors: Holmes J P , Gulabivala K , van der Stelt P F 
Published: October 2024

OBJECTIVES
To compare the diagnostic accuracy of conventional radiography with digital subtraction imaging in the detection of simulated internal resorption.

METHODS
Simulated resorption cavities were created by the sequential use of progressively larger round burs (ISO size range 006-016) in the labial wall of the coronal or apical thirds of the pulp chamber of the maxillary incisors of two cadavers. Five viewers examined 120 pairs of radiographs, one of each pair being baseline (no lesion) and the other with or without a lesion. The process was then repeated with subtraction images of the pairs of radiographs. Receiver Operating Characteristic (ROC) analysis was used to compare the diagnostic accuracy of the two imaging modalities.

RESULTS
Using conventional radiography, the minimum lesion size detectable coronally was in the 'medium' range (ISO size 010 and 012 round burs), but only 'large' lesions (ISO size 014 and 016) could be detected in the apical region. The overall diagnostic accuracy of subtraction imaging was superior to conventional radiography but only significant (P&lt;0.05) for coronal lesions.

CONCLUSION
Subtraction radiography may be a useful tool for detecting and monitoring the progress of internal root resorption.
The use of panoramic radiography in a dental accident and emergency department
Authors: Sewell J , Drage N , Brown J 
Published: October 2024

OBJECTIVES
To determine the rate of appropriate requests for panoramic radiography (PR) in a Dental Accident and Emergency Department and the implications for patient dose.

METHODS
Two hundred and seventy-one requests for PR during July 1998 were assessed by two dental radiologists and categorised as appropriate or inappropriate based on established selection criteria. Incidental findings that might alter patient management were also noted.

RESULTS
One hundred and fifty-seven requests (58%) were considered appropriate and 114 (42%) inappropriate. The most common inappropriate request was to assess disease localised to one or two teeth. Dental students were involved in 186 requests and 76 of these (41%) were inappropriate. The estimated saving in collective radiation dose over the month of the study if appropriate radiographs had been taken, would have been approximately 540 microSv, a reduction of 70%. Three out of 114 (3%) inappropriate, PRS showed minor incidental findings.

CONCLUSIONS
A considerable proportion of requests for PR were inappropriate. In most of these cases, periapical radiographs would have provided more detail with less radiation dose. The large number of inappropriate requests involving dental students has implications for educators. The use of local selection criteria based on currently accepted guidelines would have reduced the dose substantially.
Comparison of five methods for the derivation of spectra for a constant potential dental X-ray unit
Authors: Lankipalli B R , McDavid W D , Dove S B , Wieckowska E , Waggener R G , Mercier J R 
Published: October 2024

OBJECTIVES
To compare the diagnostic X-ray spectra derived by different methods for a constant potential dental X-ray unit.

MATERIALS AND METHODS
Five methods of deriving X-ray spectra for a constant potential dental X-ray unit were compared: measurement by spectrometer using cadmium-zinc-telluride (CZT) detector, calculation by Monte Carlo simulation, calculation by two different, semi-empirical methods and estimation from transmission data. The dental X-ray set was a Heliodent MD unit (Sirona, Charlotte, NC, USA) operable at 60 or 70 kV. A semiconductor detector was used in the spectrometer measurements and an ionization chamber dosimeter in the transmission measurements. From the five methods, photon-fluence spectra were derived. Based on the photon-fluence spectra, average energies and transmission curves in aluminum were calculated.

RESULTS
For all five methods, the average energies were within 2.4% of one another. Comparison of the transmission curves showed an average difference in the range of 1 to 6%.

CONCLUSION
All of the five methods of deriving spectra are in extremely good agreement with each other.
Scintigraphic evaluation of chronic osteomyelitis of the mandible in SAPHO syndrome
Authors: Sato T , Indo H , Kawabata Y , Agarie R , Ishigami T , Noikura T 
Published: October 2024

Abstract
A patient with SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis and osteitis) was evaluated by combined scintigraphy. (99m)Tc HMDP scintigraphy showed accumulation in the sternum and lumbar vertebrae as well as the right mandible, whereas (67)Ga citrate showed an accumulation in the right mandible, but not in the sternum or lumbar vertebrae. These results are consistent with chronic osteomyelitis in the mandible.
The effect of the number of iterative restorations on tuned aperture computed tomography for approximal caries detection.
Authors: Abreu M , Tyndall D A , Ludlow J B , Nortjé C J 
Published: October 2024

OBJECTIVES
To determine whether the number of iterative restorations performed on TACT images affects observers' ability to detect dental caries.

METHODS
Eight TACT basis images of 40 extracted human posterior teeth were acquired using a CCD sensor. TACT slices of each tooth were generated and subsequently submitted to 1, 2 or 3 iterative restorations. Stacks of images from the three experimental conditions were presented to six observers in a balanced order, on a high-resolution 21' color monitor. Observers scored the presence or absence of approximal caries using a 5-point confidence scale. Observers' assessments were compared with the results of histological examination. Receiver operating characteristic (ROC) curves were generated and possible significant differences between observers and between modalities tested by ANOVA. The level of significance was set at alpha=0.05. Interobserver reliability was calculated as intraclass correlation.

RESULTS
Mean areas under the ROC curves (A(z)) for the three experimental conditions were 0.791 (one iterative restoration), 0.81 (two iterative restorations), and 0.778 (three iterative restorations). ANOVA did not demonstrate any significant difference between modalities (P=0.25) but did so between observers (P=0.031). Interobserver reliability was similar for all experimental conditions tested.

CONCLUSIONS
Varying the number of iterative restorations from one to three does not affect observers' ability to detect approximal caries with TACT slices.
Unilateral fibroadipose degeneration of the masticatory muscles
Authors: Pomatto E , Castellano S , Bianchi S D 
Published: October 2024

Abstract
A unique case of fatty replacement of the masticatory muscles, causing progressive limitation of mouth opening, is presented. Both CT and MRI revealed an almost total substitution of the masticatory muscles with fatty tissue, confirmed by the histopathology at surgery. Myotomy of masseter and internal pterygoid muscles and coronoidotomy improved his symptoms. There is no known cause of fibroadipose replacement of muscle fibres.
Imaging of temporomandibular joint ankylosis. A new radiographic classification
Authors: El-Hakim Ibrahim E , Metwalli S A 
Published: October 2024

OBJECTIVES
To compare the pre-operative clinical and radiographic findings of temporomandibular joint (TMJ) ankylosis with those found at operation and propose new classification.

METHODS
Thirty-three patients were treated for TMJ ankylosis. There were 18 unilateral and 12 bilateral cases. All patients underwent pre-operative clinical and radiographic examination, (consisting of a panoramic radiograph, axial and coronal CT. The surgical findings were compared with the imaging features.

RESULTS
Post-contrast coronal CT was the best imaging modality for planning surgery as it displayed the anatomical relationship between the ankylosed segment and the surrounding vital structures, particularly where the sphenoid and temporal bones were involved.

CONCLUSIONS
Surgical planning should be based on coronal and axial CT. A new classification of TMJ ankylosis based on the CT findings is proposed.
Recurrent conventional cemento-ossifying fibroma of the mandible
Authors: Knutsen B Mork , Larheim T A , Johannessen S , Hillestad J , Solheim T , Koppang H Stromme 
Published: October 2024

Abstract
Cemento-ossifying fibromas are slow growing, benign lesions. Recurrence is considered rare. A mandibular periapical radiolucent lesion in a 30-year-old female was diagnosed histologically as a cemento-ossifying fibroma and excised. A recurrence was found 2 years and 6 months postoperatively. CT demonstrated that the recurrent lesion was larger than indicated by conventional radiography.
Denervation atrophy of the masticatory muscles in a patient with nasopharyngeal cancer: MR examinations before and after radiotherapy
Authors: Ariji Y , Fuwa N , Tachibana H , Ariji E 
Published: October 2024

Abstract
We report on a patient with denervation atrophy of the masticatory muscles due to nasopharyngeal cancer who received therapeutic irradiation. Magnetic resonance imaging has significantly contributed to aid diagnosis of this pathology. Masticatory muscle atrophy should be a definitive finding of perineural invasion caused by head and neck tumors. Radiologists should be familiar with this appearance to avoid confusion with tumor invasion of the muscle.
Spontaneous resolution of simple bone cysts.
Authors: Damante J H , Da S Guerra E N , Ferreira Jr O 
Published: October 2024

OBJECTIVE
To determine whether spontaneous resolution of simple bone cysts (SBC) is possible.

METHODS
Ten patients were diagnosed as SBC on clinical and radiographic criteria and followed up for 1 to 7 years (mean 3.8). The degree of resolution was assessed subjectively by four radiologists and objectively by changes in the grey level histogram.

RESULTS
All cases remained asymptomatic over the follow-up period. One of the lesions was considered static, two were increased, six remodeled and one resolved. The mean difference in grey levels between the lesion and the contralateral normal mandible decreased in 8 out of 10 cases.

CONCLUSION
It is probable that SBC resolves spontaneously. A protocol for clinical and radiographic diagnosis and follow-up is proposed.