bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparison of three intra-oral storage phosphor systems using subjective image quality
Authors: Kitagawa H , Farman A G , Scheetz J P , Brown W P , Lewis J , Benefiel M , Kuroyanagi K
Published: October 2024

OBJECTIVE

To compare the subjective image quality of three intra-oral storage phosphor systems.

METHODS

DenOptix (Dentsply/Gendex, Chicago, IL, USA), Digora (Soredex, Helsinki, Finland), and CD-Dent (DigiDent Digital Imaging Technologies, Nesher, Israel) were compared. Two different imaging plates (IPs), BAS300 and HR300 (Fuji Photo Film Co., Tokyo, Japan) were used with the DenOptix system. The specimen was the maxilla and surrounding soft tissues of an adult cadaver. Imaging was at 70 kVp and 8 mA with a focus-detector distance of 38 cm using an optical bench. The exposure times were varied and a panel of five dentists independently evaluated the images produced with each system/IP receptor for seven features; proximal caries, gingival soft tissues, cortical bone, root canal space, root apices, periodontal ligament space and endodontic instrument clarity on a three-interval confidence scale. The best three exposures were chosen according to the highest scores for each system. These images were re-read in random order a total of 10 times. Pair-wise comparisons were made by use of odd's ratio analysis. A 95% confidence interval was applied.

RESULTS

Images made with the DenOptix system/BAS IP combination were perceived to have the best overall image quality. The DenOptix/HR IP combination and Digora were rated almost equally in second place. The DigiDent system was ranked inferior. The Digora was considered to be the best for demonstrating gingival soft tissues (P < 0.05) and the DenOptix/HR300 combination the best for clarity of endodontic instruments (P < 0.05).

CONCLUSIONS

While the DenOptix/BAS 300 combination was rated highest overall, the ranking of image quality by modality was found to be task-dependent. Digora was rated best for demonstrating gingival soft tissues.
Computed tomography and ultrasonography of metastatic cervical lymph nodes in oral squamous cell carcinoma
Authors: Yuasa K , Kawazu T , Nagata T , Kanda S , Ohishi M , Shirasuna K
Published: October 2024

OBJECTIVES

To define criteria for CT and US in differentiating cervical lymph node metastases in oral squamous cell carcinoma (SCC).

MATERIALS AND METHODS

CT and/or US of 230 metastatic lymph nodes and 228 benign lymph nodes in 147 patients with oral SCC were retrospectively evaluated. The CT and US findings of each lymph node were compared with the histopathological findings. A metastasis was defined on CT as a lymph node with rim or heterogeneous enhancement, or measuring 10 mm or more in the short axis, regardless of enhancement pattern, and on US as having definite internal echoes, regardless of size, or without definite internal or hilar echoes, but measuring 10 mm or more in the short axis. A lymph node with hilar echoes or a ratio of the long to short axis (L/S ratio) of 3.5 or more was considered benign. A lymph node failing to comform to any of these categories was termed questionable.

RESULTS

The positive predictive value (PPV) for CT was 90.8% and the negative predictive value (NPV) was 70.4%. However, 65.7% of all lymph nodes could not be classified as either metastastic or benign. PPV for US was 96.5% and NPV was 88.1%. 25.5% of all lymph nodes could not be classified as either metastatic or benign.

CONCLUSIONS

Despite limitations in detecting metastases, by including a third category 'questionable' our criteria appear clinically more useful than other current methods based on two groups only.
Ultrasound-guided retrieval of labial minor salivary gland sialoliths
Authors: Ng S Y , Pinto P
Published: October 2024

We report a case of minor salivary gland sialolithiasis presenting as acute, painful swelling of the upper lip. Conventional, unguided, incision and drainage removed three of the sialoliths. Diagnostic ultrasound identified two further sialoliths which were successfully removed with real-time, ultrasound-guided, needle localization. This technique of sialolith retrieval has not been previously reported.
Dimensions and volumes of the orbit and orbital fat in posttraumatic enophthalmos
Authors: Ramieri G , Spada M C , Bianchi S D , Berrone S
Published: October 2024

OBJECTIVES

To estimate from 2D and 3D-CT the anatomical defects that are most likely to be responsible for posttraumatic enophthalmos.

MATERIALS AND METHODS

The morphology and dimensions of the orbit and of fat content were investigated in 25 patients 6-12 months after treatment for complex orbital fractures by image analysis and volumetric estimation from 2D and 3D-CT.

RESULTS

The shape of orbit was very often changed from conical to more rounded due to enlargement of the posterior segment. The retrobulbar fat appeared fragmented and dislocated posteriorly. No changes were observed in the structural appearance or radiodensity of either the orbital fat or muscles. There was reduced sagittal eye projection, increased width of the orbital rim, downward dislocation of the posteromedial orbital floor, and increased volume in the posttraumatic orbits which was significantly different (P < 0.05). Enophthalmos was correlated with orbital volume and height of the retrobulbar portion of the orbit. The volume of fat did not correlate with enophthalmos.

CONCLUSIONS

Posttraumatic enophthalmos appears to be more commonly related to failure in correcting the orbital volume and in reducing the outward dislocation of the posterior orbital floor and not to changes in the fat content.
A comparative study of the radiological diagnosis of postoperative maxillary cyst
Authors: Heo M S , Song M Y , Lee S S , Choi S C , Park T W
Published: October 2024

OBJECTIVES

To compare the diagnostic accuracy for the postoperative maxillary cyst (POMC) of panoramic in combination with Waters' radiography with computed tomography (CT) and of oral and maxillofacial radiologists with non-specialists.

STUDY DESIGN

Nineteen cases of POMC and 19 of postoperative changes were assessed using panoramic in combination with Waters' radiographs and CT by five oral and maxillofacial radiologists and five non-specialists on a five-point scale. The areas under the ROC curves were analysed using the Wilcoxon rank sum test to determine any differences in diagnostic accuracy between the two methods and between the two groups.

RESULTS

The diagnostic accuracy of CT was higher than that of combined panoramic and Waters' radiographs for the oral and maxillofacial radiologists (P < 0.05), but not for the non-specialists (P > 0.05). The diagnostic accuracy of the oral and maxillofacial radiologists for each method was higher than that of the non-specialists group (P < 0.05).

CONCLUSIONS

CT improves the evaluation of POMC. Radiological training and experience leads to more accurate diagnoses.
Two cases of polyostotic eosinophilic granuloma
Authors: Asaumi J , Konouchi H , Hisatomi M , Matsuzaki H , Kishi K
Published: October 2024

We report two cases of polyostotic eosinophilic granuloma (EG). Both plain radiographs and CT showed diffuse osteolytic lesions which suggested malignant tumors. Although EG was polyostotic, the prognosis was relatively good. Both cases developed new lesions over a follow-up period of 4-5 years and therefore further long-term review is needed.
Tuned-aperture computed tomography for detection of occlusal caries
Authors: Shi X Q , Han P , Welander U , Angmar-Månsson B
Published: October 2024

OBJECTIVES

To evaluate the use of tuned-aperture computed tomography (TACT) for the detection of primary occlusal caries.

MATERIALS AND METHODS

The material comprised 76 extracted posterior teeth, 51 with caries. Radiographs were recorded both with the Sens-A-Ray (Regam Medical Systems Int. AB, Sundsvall, Sweden) digital radiographic system and with Kodak EktaSpeed Plus film (Eastman-Kodak Co., Rochester NY, USA) employing an Orthopantomograph OP 100 (Instrumentarium Imaging, Tuusula, Finland) and a Prostyle Intra (Planmeca, Helsinki, Finland) dental unit respectively. The Sens-A-Ray radiographs were used to construct TACT slices and TACT iterative slices. The teeth were subsequently sectioned in 300 microm thick slices. Microradiographs were exposed and analysed with respect to the true presence of lesions. Seven observers subjectively evaluated the radiographs and ROC analyses performed. Conventional radiographs were compared with TACT images by means of the area under the ROC curves, Az. Paired t-test was used to compare Az values. Interobserver agreement was evaluated using the Kendall coefficient and the Friedman Anova.

RESULTS

TACT radiographs were significantly better than conventional radiographs for diagnosing all types of occlusal caries combined (P(TACT) (slices)=0.02. P(TACT) (iterative slices)=0.01). However, neither TACT system was significantly better than film for enamel and dentinal caries separately. Observer agreement was moderate. However, observers demonstrated significant systematic differences in their readings (P<0.001).

CONCLUSION

TACT may be a feasible method for diagnosing primary occlusal caries.
Group learning factors in a problem-based course in oral radiology
Authors: Chen S K , Chang H F , Chiang C P
Published: October 2024

OBJECTIVES

To assess the development of group dynamics in students who participated in a problem-based learning (PBL) course in oral radiology and to evaluate the influence of the facilitators' experience.

METHODS

At the beginning and end of the course, students in three consecutive years (1997, 1998 and 1999) responded to a group learning factor questionnaire designed to measure group dynamics (engagement, interpersonal relationships, lack of commitment and disruptive behaviour, interpersonal learning and self-presentation). The answers were analysed with paired t-test and the effects of the facilitator's seniority, expertise in oral radiology, experience of PBL and single or rotating facilitators assessed.

RESULTS

Most groups in the three years reported above average group dynamic scores. There were significant changes in group dynamics. In the 1997 class, interpersonal relationships improved (P=0.014). In the 1998 class, interpersonal learning (P=0.021) and engagement (P=0.009) increased significantly, while disruptive behaviour decreased (P=0.031). In the 1999 class, lack of commitment and disruptive behaviour decreased (P=0.014). Groups led by a junior faculty member with no previous experience of PBL show less commitment and more disruptive behaviour.

CONCLUSIONS

More commitment and less disruptive behaviour and improved engagement, interpersonal relationships and self-presentation were found in a PBL course in oral radiology. Facilitators should have prior exposure to PBL to avoid disruptive behaviour among the students.
Performance of a new F-speed film for caries detection
Authors: Ludlow J B , Abreu M , Mol A
Published: October 2024

OBJECTIVE

To compare films from three speed groups for the detection of approximal caries.

STUDY DESIGN

Insight, Ektaspeed Plus and Ultra-speed (Eastman-Kodak, Rochester, NY, USA) radiographs of the proximal surfaces of 40 extracted posterior teeth were evaluated by six observers. The presence or absence of caries was scored using a 5-point confidence scale. The actual status of each surface was determined from histology of ground sections. Observer responses were evaluated using ROC analysis and areas under the ROC curves (A(Z)) assessed using ANOVA.

RESULTS

Ultra-speed film had a mean A(Z) of 0.88, Ektaspeed Plus 0.85, and Insight 0.84. These differences were not statistically significant (P=0.5). Differences between observers were also not statistically significant (P=0.42).

CONCLUSIONS

The performance of the new F-speed film was not statistically different from E or D speed for caries detection. This film shows promise as a means of reducing patient dose while maintaining diagnostic quality.
A rare case of intraosseous polymorphous low-grade adenocarcinoma (PLGA) of the maxilla
Authors: Sato T , Indo H , Takasaki T , Kawabata Y , Morita Y , Noikura T
Published: October 2024

A rare case of intraosseous, polymorphous low-grade adenocarcinoma (PLGA) of the maxilla is presented. The lesion appeared to be cystic radiographically and the only finding which suggested malignancy was an irregular cortical border.
Integration of a picture archiving and communication system with videocapture and computed radiography in a dental hospital
Authors: Okamura K , Tanaka T , Yoshiura K , Tokumori K , Yuasa K , Kanda S
Published: October 2024

A method for the integration of a picture archiving and communication system (PACS) at Kyushu University Dental Hospital with radiological information (RIS) and hospital information (HIS) systems is described. CT, US and DSA from different manufacturers were integrated by videocapture and then subsequently integrated with computed radiography (CR) by means of DICOM. The approximate amount of data stored each month on optical discs is 2 GB. The system does not incorporate intra-oral radiography.
A study of the relationship between the position of the condylar head and displacement of the temporomandibular joint disk
Authors: Kurita H , Ohtsuka A , Kobayashi H , Kurashina K
Published: October 2024

OBJECTIVES

To examine the possible relationship between condylar position and disk displacement in the TMJ.

METHODS

Forty-eight joints with no disk displacement (NDD), 84 joints with a reducible displaced disk (RDD) and 99 joints with a permanently displaced disk (PDD) were selected. The positions of the condyle and TMJ disk were calculated from lateral MR images.

RESULTS

There were significant differences in condylar position between the joints with NDD and RDD, while there was no difference between those with NDD and PDD (Kruskal-Wallis and post-hoc test, P<0.05). There was also a significant correlation between the position of the condylar and the displaced disk (Spearman's rank correlation, P<0.05). The condyle was located more anteriorly with advancing disk displacement.

CONCLUSIONS

We suggest that if the disk displacement is slight, the condyle is displaced posteriorly: as the disk displacement becomes more severe (i.e. more anteriorly displaced), the condyle returns to the concentric position.
Scanning resolution and the detection of approximal caries
Authors: Janhom A , van Ginkel F C , van Amerongen J P , van der Stelt P F
Published: October 2024

OBJECTIVE

To determine a proper scanning resolution for digitizing bitewing radiographs in the detection of approximal caries.

METHODS

Fifty-two premolars and 48 molars were mounted in blocks and imaged on conventional film (Ektaspeed Plus, Eastman-Kodak, Rochester, NY USA) simulating a bitewing projection. The 15 bitewing radiographs were then scanned with a flatbed scanner at three resolutions 150, 300 and 600 d.p.i. The digitized images were displayed in random order on a high-resolution cathode ray tube monitor. Ten observers assessed the caries status of 200 approximal surfaces. They scored lesion presence on a 5-point confidence scale and depth on a 3-point scale. The observer's scores were compared with the results from a histological examination. Data were analysed using analysis of variance, by calculating signed observer error, absolute observer error and observer confidence.

RESULTS

Lesion depth had a significant effect on confidence of lesion recognition. The main effect of resolution and the interaction between resolution and lesion depth were significant. Pair-wise comparison showed a significant difference between resolutions in case of sound surfaces and surfaces with dentinal lesions for absolute error. The confidence increased as the resolution increased but no significant difference was found between 300 and 600 d.p.i. The best score for depth estimation was obtained at the 300 d.p.i. scanning resolution.

CONCLUSIONS

When bitewing radiographs are scanned with a flatbed scanner, a resolution of 300 d.p.i. seems the best choice. At this resolution the digital file size is manageable without significant loss of the information necessary for caries diagnosis.
Paediatric absorbed doses from rotational panoramic radiography.
Authors: Hayakawa Y , Kobayashi N , Kuroyanagi K , Nishizawa K
Published: October 2024

OBJECTIVES

To determine the paediatric doses in rotational panoramic radiography with film/screen and photostimulable phosphor receptors.

STUDY DESIGN

A paediatric anthropomorphic head and neck phantom was used. Absorbed doses were measured for two panoramic systems, the Orthophos (Sirona Dental Systems, Bensheim, Germany) and the PM 2002 CC (Planmeca Oy, Helsinki, Finland), with and without programmable child settings, using both screen/film and photostimulable phosphor receptors.

RESULTS

Absorbed doses to the eye ranged from 5 to 24 micro Gy. Doses to the dental arches with the Orthophos unit ranged from 50 to 555 micro Gy with the adult and from 27 to 436 micro Gy with the child program; using the PM 2002 CC unit, doses ranged from 56 to 1040 micro Gy using the adult settings, and from 60 to 890 micro Gy with the paediatric settings. The paediatric exposure settings reduced doses at most locations for both panoramic systems. The highest doses were measured near the rotational axes of the X-ray beam. Paediatric settings with the Orthophos P10 resulted in the dose reduction more than 50% to the thyroid but not with the PM 2002 CC. When lower kVcp or mA settings were used, absorbed doses were effectively reduced for all combinations of machines, programs and detectors.

CONCLUSIONS

Specific program settings for children reduced the absorbed doses from panoramic radiography irrespective of the machine or receptor used.
Comparison of patient dose from imaging protocols for dental implant planning using conventional radiography and computed tomography
Authors: Lecomber A R , Yoneyama Y , Lovelock D J , Hosoi T , Adams A M
Published: October 2024

OBJECTIVES

To compare the radiation doses from imaging protocols for dental implant planning either using conventional radiography only (dental panoramic radiography (DPR), cephalometry and linear cross-sectional tomography) or involving computed tomography (CT).

METHODS

Organ absorbed doses were measured using a female Rando anthropomorphic phantom loaded with lithium fluoride thermoluminescent dosemeters (TLD). Standard mandibular protocols for dental implant planning were followed using either a conventional dental radiographic unit (PM 2002 CC Planmeca, Helsinki, Finland) or CT scanner (Excel Twin Elscint, Haifa, Israel). Organ absorbed and effective doses were calculated. Effective dose was calculated using two approaches, one based on the ICRP method which excludes the salivary tissue from the remainder organs (designated E(exc)), and the other with its inclusion (E(inc)).

RESULTS

The greatest individual organ doses for any examination were measured in the salivary tissue. E(exc) for panoramic, cephalometric and cross-sectional tomography using DPR was 0.004 mSv, 0.002 mSv and 0.002 mSv, respectively, whereas with CT it was 0.314 mSv. The value of E(inc) calculated using these data was between two and five times E(exc).

CONCLUSIONS

E(inc) greatly increases the apparent radiation burden, especially with high dose procedures. CT techniques can provide excellent images, but at the cost of increased radiation detriment. DPR with a cross-sectional tomography facility may give adequate clinical information at a greatly reduced dose.
Fractal dimension on dental radiographs
Authors: Bollen A M , Taguchi A , Hujoel P P , Hollender L G
Published: October 2024

OBJECTIVES

(1) To compare fractal dimension (FD) from periapical radiographs with FD from panoramic radiographs; (2) to correlate FD with cortical thickness and morphology; and (3) to correlate FD with a reported history of osteoporotic fractures.

METHODS

Information on fracture and smoking history was obtained by a telephone interview with 281 elderly (>60 years of age) patients who had periapical and panoramic radiographs exposed on the same date. FD was measured in several locations on both types of radiograph. Mandibular cortical thickness and morphology were obtained from the panoramic radiograph.

RESULTS

FD measured in the mandible was lower than FD in the maxilla. Same-jaw measurements had a higher correlation than same-side measurements. FD measured on panoramic radiographs was lower than FD from periapical radiographs. There was a negative correlation between cortical thickness and FD. FD was higher in subjects with more mandibular cortical porosities and resorption. The mean panoramic FD from subjects with a history of osteoporotic fractures was significantly higher, after adjusting for smoking, gender, age, height and weight.

CONCLUSIONS

FD measured on panoramic radiographs is lower than FD measured on periapical radiographs. FD is higher in both types of radiograph in subjects with a thinner, severely eroded mandibular cortex and a history of osteoporotic fractures. This study confirms other reports that FD increases when bone mass decreases. In addition, it suggests that panoramic radiographs can be used as a possible alternative for the measurement of FD to periapical radiographs.
Evaluation of tuned aperture computed tomography (TACT) in the localization of simulated periodontal defects
Authors: Ramesh A , Ludlow J B , Webber R L , Tyndall D A , Paquette D
Published: October 2024

OBJECTIVES

To compare the diagnostic efficacy of tuned aperture computed tomography (TACT) with the application of the 'buccal object rule' (BOR) in the localization of simulated periodontal defects.

METHODS

Thirty interproximal sites were selected in fifteen cadaver segments of maxillae and mandible. Artificial periodontal defects were created using round burs and 40% formic acid in the buccal, lingual or mid-buccolingual areas. Eight basis projections were obtained and TACT slices were reconstructed for each region of interest. Two of the basis images were used in application of BOR for localization of the defect. Eight observers scored the location of defects using TACT slices and the paired radiographs separately. Data were analysed using the kappa statistic and ANOVA.

RESULTS

A mean weighted kappa of 0.14 for localization was obtained with both BOR and TACT. Using ANOVA, there was no significant difference between modality and observer. There was however, a significant difference (P=0.019) between different defect sizes. Both modalities performed better with larger defect sizes. TACT performed slightly better than BOR when the smaller lesions were included; however, with larger lesions, this trend was reversed.

CONCLUSIONS

The results confirm the relationship between correlation distance (the resultant slice width) and object size in the application of TACT for localization. BOR remains a simple yet effective tool for localization. The clinical significance is not clear considering the low kappa scores obtained with both the modalities.
Quantitative light-induced fluorescence (QLF): a method for assessment of incipient caries lesions
Authors: Angmar-Månsson B , ten Bosch J J
Published: October 2024

OBJECTIVES

To review the literature on validation and application of the quantitative light-induced fluorescence (QLF) method for quantitative assessment of early enamel lesions in vivo and in vitro.

METHODS

QLF uses light with wavelengths around 405 nm to excite yellow fluorescence at wavelengths above 520 nm. Its diagnostic capacity is based on the mechanism that the intensity of natural fluorescence of a tooth is decreased by scattering due to a caries lesion. The equipment, the data processing and the interaction between equipment and operator are described.

RESULTS

The method has been validated by many authors; the results are presented and compared. For artificial lesions, the validation line is curved. For larger mineral losses, the curve is linear with a slope of 10% fluorescence loss corresponding with a mineral loss of 0.15 kg x m(-2). For lesions caused by natural caries, it is tentatively concluded that fluorescence loss is linear to mineral loss with a slope similar to that of artificial lesions. Reliability and reproducibility have been tested in vivo and show interexaminer values of the interclass correlation coefficient, r, of 0.93<r<0.99. Confounding factors are inadequate reconstruction of sound fluorescence values and drying of the lesion before or during measurement. In vivo application showed that statistically significant changes between different preventive regimes could be proven in only 6 months of study time.

CONCLUSION

QLF offers a potential tool to reduce the time needed for clinical research. Its objectivity will prove useful in epidemiological surveys. QLF provides visual and quantitative feedback to patients.
Influence of the validation method on diagnostic accuracy for caries. A comparison of six digital and two conventional radiographic systems
Authors: Hintze H , Wenzel A
Published: October 2024

OBJECTIVE

To evaluate the influence of the validation method on the diagnostic accuracy and the relative comparison of eight radiographic systems for caries detection.

METHODS

Three hundred and thirty-eight approximal and 145 occlusal surfaces were radiographed under standardised conditions using six CCD-based sensor systems: MPDx (Dental/Medical Diagnostic Systems Inc., Woodland Hills, CA, USA), Dixi (Planmeca, Helsinki, Finland), Sidexis (Sirona, Bensheim, Germany), RVG(old) (Trophy, Paris, France, 1994 model), RVG(new) (Trophy, Paris, France, 2000 model) and Visualix (Gendex, Milan, Italy) and two film systems: Ektaspeed Plus and Insight (Eastman Kodak, Rochester, NY, USA). Four observers examined the radiographs for approximal and occlusal caries using a five-point confidence scale. The presence of caries was validated histologically and radiographically. Diagnostic accuracy was evaluated using ROC curve areas (A(z)).

RESULTS

For both approximal and occlusal caries the mean A(z) of the eight radiographic systems was significantly higher using radiographic than histological validation (P<0.001). Using histological validation for approximal caries, Dixi (A(z)=0.71) and Ektaspeed Plus (A(z)=0.7) were not significantly different, but Dixi was significantly more accurate than the other digital systems and the Insight film. Using radiographic validation for approximal caries, Ektaspeed Plus (A(z)=0.87) was significantly more accurate than Dixi (A(z)=0.82). Dixi was significantly more accurate than MPDx (A(z)=0.74), RVG(old) (A(z)=0.77), RVG(new) (A(z)=0.77) and Visualix (A(z)=0.76). Corresponding variations were found for occlusal caries depending on the validation method. Using histological validation, MPDx (A(z)=0.76) was significantly less accurate than Dixi (A(z)=0.81), Sidexis (A(z)=0.8), Ektaspeed Plus (A(z)=0.82) and Insight (A(z)=0.81). Using radiographic validation, MPDx (A(z)=0.83) was also significantly less accurate than RVG(old) (A(z)=0.89) and RVG(new) (A(z)=0.9).

CONCLUSION

A(z) obtained from radiographic validation was significantly higher than A(z) obtained from histological validation. Comparison of the diagnostic efficacy for caries of the eight radiographic systems was strongly influenced by the validation method. DOI: 10.1038/sj/dmfr/4600645
Comparison of three-dimensional computed tomography with rapid prototype models in the management of coronoid hyperplasia
Authors: Asaumi J , Kawai N , Honda Y , Shigehara H , Wakasa T , Kishi K
Published: October 2024

OBJECTIVES

To compare (1) the accuracy of 3DCT with rapid prototyping (RP) models and (2) their application in the management of coronoid hyperplasia.

METHODS

An adult dry skull was used to compare 3DCT and a RP model for accuracy of reproduction; Polymerisation contraction and 17 distances between 27 anatomical points were measured. Two patients with coronoid process hyperplasia were assessed by means of 3DCT and plastic models.

RESULTS

Differences in measurements with the RP model and the dried skull were smaller than those with 3DCT (P=0.04). Polymerisation contraction was greater than the errors in reproduction with the RP model and approximately equal to those with the 3DCT. The coronoid process was thick and prominent in the patients with coronoid process hyperplasia and the small space and early contact between zygomatic arch and the coronoid process demonstrated. The plastic model duplicated the exostosis of the inner surface of the malar bone facing the concavity of the elongated process. The coronoid process had an anterior tilt in one case.

CONCLUSION

The plastic model duplicated the relationship between the maxillofacial deformity and the coronoid process with tolerable accuracy. Trismus may be due to the direction as well as the length of the enlarged coronoid process.
Effect of dose reduction in digital dental panoramic radiography on image quality
Authors: Dannewitz B , Hassfeld Stefan , Eickholz P , Mühling J
Published: October 2024

OBJECTIVES

To investigate the effect of dose reduction in digital panoramic radiography on subjective image quality and diagnostic performance.

METHODS

Two digital panoramic radiographs were obtained with the Orthophos DS(Sirona, Bensheim, Germany) of patients (n=100) receiving dental care. The first image was taken at the standard exposure setting. For the second image the tube current was reduced by between 48 and 53%, 63 and 69%, 75 and 80% and 80 and 81% respectively. Ten observers rated both images for 21 specific anatomical details and 30 pathological findings.

RESULTS

All radiographs taken at reduced mA levels had a significantly inferior score (P<0.01) for anatomical details. There was no difference in the scores for pathological findings.

CONCLUSION

Radiographs obtained at reduced mA had inferior subjective image quality, but there was no difference in diagnostic performance. Thus, a reduction in tube current of approximately 50% is recommended. In certain circumstances such as follow-up radiographic examinations, a reduction of up to 65% should be considered.
Comparing the accuracy of Dutch dentists and dental students in the radiographic diagnosis of dentinal caries
Authors: Mileman P A , van den Hout W B
Published: October 2024

OBJECTIVES

To compare the diagnostic accuracy of dental students using bitewing radiographs for the diagnosis of dentinal caries with that of general dental practitioners and to establish a bench mark for testing for improvement in diagnostic performance.

METHODS

Fourth year dental students (n=259) viewed bitewing radiographs of 105 proximal tooth surfaces. According to a micro-radiography "gold standard" 45 surfaces had dentine caries. The students were asked to diagnose presence and absence of dentine caries from which, under supervision, they calculated their sensitivity (TPR) and false positive rate (FPR). The students binary diagnostic data was compared with the historical data from a random sample of Dutch dentists (n=273). The Summary Receiver Operating Characteristic (SROC) curve method was used to analyse the data. The two groups were tested for differences in (a) diagnostic odds ratio and (b) the area under the SROC curve.

RESULTS

The students mean TPR for dentine caries diagnosis was 67.2% (s.d. 11.8%) and the FPR was 8.3% (s.d. 8.4%). The corresponding values for dentists were: TPR 54.0% (s.d. 14.1%) and FPR 3.1% (s.d. 4.5%). Significantly more dentists (85%) than students (72%, P<0.001) had a diagnostic odds ratio > or =21. The area under the SROC curve (Az) was 0.8194 for students and 0.8140 for dentists (P=0.70).

CONCLUSIONS

In our study (i) the students had a higher TPR but also a higher FPR than the dental practitioners, (ii) their overall performance (Az) was similar but (iii) for a clinically relevant population the dental practitioners would out-perform the students in diagnostic performance.
The genu of the submandibular duct--is the angle significant in salivary gland disease?
Authors: Drage Nicholas A , Wilson R F , McGurk M
Published: October 2024

OBJECTIVES

To investigate whether the angle of the genu of the submandibular duct is a significant contributory factor in the development of salivary calculi or sialoadenitis.

METHODS

A preliminary test with a phantom was performed, taking oblique lateral views with different vertical and horizontal beam angulations to assess the effect on the genu angle. The phantom comprised a dried mandible and a piece of wire bent to simulate the submandibular duct. There were no differences in the measured angle of the bend in the wire within the range of beam angulations used in the clinical study. One hundred and two sialographs were analysed from three separate groups of patients, normal controls (n=18), proven salivary calculi (n=61) and those with sialoadenitis (n=23). The oblique lateral radiographs were digitised and imported into the Denoptix digital system, and the angle measured using the VixWin 2000 software. Differences in angle between groups were investigated using analysis of variance.

RESULTS

The mean angle of the genu was 103 degrees (range 41 degrees-147 degrees) in the control group, 108 degrees (range 46 degrees-178 degrees) salivary calculi group, and 91 degrees (range 24 degrees-155 degrees) in sialoadenitis patients. There were no statistical differences in the angle between the groups.

CONCLUSIONS

There is a wide variation in the angle of the genu of the submandibular duct (24 degrees -178 degrees ). This angle does not appear to be associated with either sialolithiasis or sialoadenitis.
Precise image-receptor calibration and monitoring of beam quality with a step wedge
Authors: Couture R A , Hildebolt C F
Published: October 2024

OBJECTIVE

To describe an extended bootstrap calibration procedure that uses a step-wedge absorber and minimal equipment for rapid, accurate calibration of image receptors and simultaneous monitoring of beam quality.

METHODS

Multiple radiographs of a step wedge are made at different exposures, with a precision dosimeter as a reference. An iterative least-squares minimization procedure is used to fit the data with a single calibration function. The calibration range can be extended by varying two exposure parameters in addition to stepwedge thickness. Small variations in beam quality and other experimental artifacts can be detected by testing redundant data for self-consistency. As a demonstration, two photostimulable phosphor (PSP) systems were calibrated, one with a well-regulated X-ray source and the other with a poorly regulated source.

RESULTS

The first PSP system was calibrated over a range of 3.2 orders of magnitude with a relative standard deviation of the estimate of only 0.36%. The slope of the calibration curve agreed with the nominal, factory-set value within 0.8% (on a logarithmic scale). The second PSP system had a nearly linear response with a relative standard deviation of the estimate of 0.44% over the upper 97% of its range. Both X-ray sources showed easily detectable variations in tube potential.

CONCLUSIONS

The new calibration method eliminates many of the sources of error of previous techniques such as inverse-square sensitometry. If a suitably precise X-ray source is available, the relative accuracy is limited only by the precision of the receptor system.
Virtual radiographs computed from TACT volume data as a gold standard for image registration prior to subtraction
Authors: Lehmann T M , Hemler P F , Webber R L
Published: October 2024

OBJECTIVE

To develop a three-dimensional (3D) model for quantitative analysis of image subtraction methods simulating clinical conditions and relevant to dental radiology.

METHOD

A high-resolution volume representation of a formalin-preserved segment of a human maxilla was synthesized from a set of 51 digital radiographs equidistantly covering the entire sampling aperture by means of Tuned-Aperture Computed Tomography (TACT). Two-dimensional (2D) projection renderings of a 3D model were generated yielding arbitrary but well-known 2D projections with, and without, structured noise producing 'virtual radiographs'.

RESULTS

Virtual radiographs were found to be similar to actual clinical images with respect to appearance, structure, and texture. Because the TACT reconstruction process allows all possible positions and orientations of source, specimen, and image plane to be simulated with negligible under sampling over a reasonable range of solid angles (sampling aperture), the resulting 3D model provided a rigorous method for establishing a truly objective gold standard (ground truth) for testing different registration techniques.

CONCLUSIONS

TACT image registration can be assessed quantitatively by comparing actually observed vs theoretically professed parameters that presumably constrain the underlying projection geometries. Other attributes that vary from one method to the next, such as the use of nonlinear or region-specific techniques to facilitate registration, likewise, now can be rigorously measured by context-based methods such as quantitative determination of image similarity. Hence, a 3D model that renders idealized virtual radiographs from any desired projection geometry makes possible truly objective comparison of various digital subtraction techniques.
Tetraploidy and Fe2O3 nanoparticles: dual strategy to reduce the Cd-induced toxicity in rice plants by ameliorating the oxidative stress and downregulation of metal transporters
Authors: Ghouri Fozia , Shahid Munazzam Jawad , Ali Shafaqat , Ashraf Humera , Alomrani Sarah Owdah , Liu Jingwen , Alshehri Mohammed Ali , Fahad Shah , Shahid Muhammad Qasim
Published: October 2024

Whole-genome doubling or polyploidy increases the plant tolerance ability against biotic and abiotic stress.
Techno-functional, antioxidant, and amino acid characterization of hydrolyzed bioactive peptides from coconut (Cocos nucifera L.) meal protein
Authors: Zolqadri Roshanak , Akbarbaglu Zahra , Sarabandi Khashayar , Peighambardoust Seyed Hadi , Jafari Seid Mahdi , Mousavi Khaneghah Amin
Published: October 2024

In this study, the techno-functional characteristics and nutritional value of coconut meal protein (CMP) and the obtained polypeptides by alcalase (H-Alc), trypsin (H-Try), pancreatin (H-Pan), and pepsin (H-pep) were investigated.
Human milk oligosaccharides and milk fat globule membrane reduce allergic reactions in mice through the modulation of gut microbiota and metabolic functions
Authors: Chen Xinzhang , Yang Shengjun , Guo Zhengtao , Li Bailiang , Wang Zhongjiang , Jiang Lianzhou
Published: October 2024

Human milk oligosaccharides (HMOs) and the milk fat globule membrane (MFGM) represent novel treatments for cow's milk allergy (CMA).
Modification of ZnO gas-diffusion-electrodes for enhanced electrochemical CO2 reduction: optimization of operational conditions and mechanism investigation
Authors: Marrenjo Gonçalves J. , da Silva Gelson T. S. T. , Muñoz Rodrigo A. A. , Mascaro Lucia H. , Lopes Osmando F.
Published: October 2024

Amino-functionalized ZnO exhibits enhanced CO2 adsorption capacity and selectivity for electrochemical conversion of CO2 to CO.
Technical, preclinical, and clinical developments of Fc-glycan-specific antibody–drug conjugates
Authors: Yang Qiang , Liu Yunpeng
Published: October 2024

Fc-glycan-specific ADC is a significant advance in site-specific ADCs for cancer therapy. Notably, JSKN003 and IBI343 have demonstrated promising results in phase 1 clinical trials and are advancing into phase 3 studies.
Recent innovations in interfacial strategies for DLP 3D printing process optimization
Authors: Wu Lei , Song Yanlin
Published: October 2024

This review summarizes recent interfacial strategies for DLP 3D printing process optimization from the view of interfacial interactions between solid and liquid phases which are influenced by resin formation, curing surfaces and light sources.
Recent advances in tungsten oxide-based chromogenic materials: photochromism, electrochromism, and gasochromism
Authors: Zhang Yaqi , Ding Yilin , Lan Fan , Zhang Wenjing , Li Jingfa , Zhang Rufan
Published: October 2024

Applications of WOx in photochromic, electrochromic, and gasochromic materials and devices.
Retraction: Stacking of nanorings to generate nanotubes for acceleration of protein refolding
Authors: Kameta N. , Ding W.
Published: October 2024

Retraction of ‘Stacking of nanorings to generate nanotubes for acceleration of protein refolding’ by N. Kameta and D. Wing, Nanoscale, 2021, 13, 1629–1638, https://doi.org/10.1039/D0NR07660K.
The photo-isomerization of the cyclononatetraenyl ligand and related rare earth complexes
Authors: Pedussaut Lucie , Mahieu Nolwenn , Chartier Camille , Rajeshkumar Thayalan , Tricoire Maxime , Douair Iskander , Casaretto Nicolas , Maron Laurent , Danoun Grégory , Nocton Grégory
Published: October 2024

Reversible light isomerization in organometallic complexes of lanthanides: the low-energy wavelengths favor the cis isomer, and the high-energy wavelengths favor the trans isomer.
Interfacial charge transfer modulation in laser-synthesized catalysts for efficient oxygen evolution
Authors: Lee Dong Hyeon , Kerkar Rahul , Arumugam Deepak , Theerthagiri Jayaraman , Ramasamy Shankar , Kheawhom Soorathep , Choi Myong Yong
Published: October 2024

This study introduces a NiFe LDH-based catalyst via pulsed laser irradiation in liquids and microwave methods, achieving superior oxygen evolution performance. In situ electrode casting optimizes the catalyst for water-splitting applications.
Physically crosslinked polyacrylates by quadruple hydrogen bonding side chains
Authors: Verjans Jente , André Alexis , Sedlačík Tomáš , Aksakal Resat , van Ruymbeke Evelyne , Hoogenboom Richard
Published: October 2024

Dynamic polymer materials with improved mechanical properties can be obtained by introducing supramolecular interactions between the polymer chains as demonstrated here by introducing ureidopyrimidinone quadruple hydrogen bonding units in the side chains of polyacrylates.
Higher-order modal parameter estimation and verification of cross-laminated timber plates for structural-acoustic analyses
Authors: Vallely Sven , Schoenwald Stefan
Published: October 2024

Cross-Laminated Timber (CLT) is a wood composite that is popular due to its favourable stiffness-to-mass-density ratio and environmental benefits, among other positive attributes. This paper presents the estimation of higher-order modal parameters and their use in the verification and validation of an Equivalent Single-Layer (ESL) CLT model. The eigenvectors, eigenfrequencies, and modal damping ratios of 20 out-of-plane vibration modes were experimentally determined. The experimentally determined eigenfrequencies and eigenmodes were correlated and compared to those derived from a numerical model. The modal damping ratios were compared to damping loss factors derived from the power injection method. A broadband frequency view is also considered, with the comparison of experimental and numerical forced response models. As part of the verification and validation process, a framework of key indices and respective criteria is suggested and discussed in this contribution. Over the course of the paper, an ESL CLT model which derives its properties from a layerwise basis is validated in detail against experimental measurements. The results are intended to be of relevance to both structural and acoustic domains.
Collective-subspace requantization for sub-barrier fusion reactions: Inertial functions for collective motions
Authors: Ruike Chisato , Wen Kai , Hinohara Nobuo , Nakatsukasa Takashi
Published: October 2024

The adiabatic self-consistent collective coordinate (ASCC) method is used to determine the optimum reaction path and to calculate the potential and the inertial functions of the reaction model. The properties of the inertial functions are investigated with the ASCC method, in comparison with those of the cranking formulae. In addition, the properties of the pair rotation are investigated in the BCS pair model. The moments of inertia for rotation in both the real and the gauge spaces may decrease as the deformation develops.
The superheavy nuclei: Fusion-evaporation reactions
Authors: Khuyagbaatar J.
Published: October 2024

The synthesis of superheavy elements beyond the oganesson (Og, Z = 118) remains one of the actual topics in nuclear physics. For this purpose, the fusion reactions with projectiles heavier than 48Ca, which were successfully implied for the synthesis of the heaviest elements, and actinide targets have to be used. However, empirical knowledge on such reactions is almost absent. In this work, the experimental cross sections of the “hot”, “cold”, and 48Ca+actinide reactions were analyzed to reveal their differences in the three steps of the fusion-evaporation process. The evaporation residue cross sections represented as a function of the mean fissility parameter show the hitherto unnoticed difference between the “hot” and “cold” fusion reactions, which is in agreement with nuclear reaction dynamic studies. Based on the newly suggested systematics, the evaporation residue cross sections for the 50Ti, 51V, 54Cr, 58Fe and 64Ni-induced reactions with actinide targets were estimated within the two different empirical approaches.
Low-energy fusion hindrance in medium-light systems
Authors: Montagnoli Giovanna
Published: October 2024

Heavy-ion fusion reactions give fundamental information on the quantum tunnelling of many-body systems where several intrinsic degrees of freedom are contributing. Moreover, the existence of hindrance in the fusion of light systems is critical for a variety of stellar environments.

Hindrance is often characterised by a maximum of the astrophysical S factor with decreasing energy, and is an interesting link between heavy-ion fusion and astrophysics. The underlying physical background is still under debate. Recently it has been pointed out that the Pauli exclusion principle influences the ion-ion potential and, as a consequence, low-energy fusion hindrance is produced because of the thicker and higher Coulomb barrier. We recently performed systematic investigations on the fusion of several medium-light systems to establish a reliable basis for the extrapolation to the lighter cases of astrophysical interest. The results obtained for 12C + 24,26Mg and 12C + 30Si are discussed here. Hindrance is observed in all cases, however, with differing features, so extrapolating to lighter systems is not straightforward. Additionally, oscillations are observed in the sub-barrier logarithmic slopes of the 12C + 24,26Mg excitation functions, which complicates identifying the hindrance threshold in those two cases.

Coupled-channels calculations for all these systems have been performed. The results show that fusion cross sections are well reproduced by simple tunnelling through the potential barrier, at the lowest energies. An alternative way to represent the data is discussed, which helps identifying the various channel couplings.
Optical properties and applications of laser-induced disordered plasmonics metasurfaces
Authors: Destouches Nathalie
Published: October 2024

The lecture explores laser-induced plasmonic metasurfaces, focusing on their structural characteristics and optical properties. Despite their disordered nature, these metasurfaces excel in applications such as color printing, sensing, light manipulation, and energy harvesting, offering advantages over traditional ordered structures through detailed case studies.
30 years of PPLN-what is old, what is new, and where next for PPLN and QPM material research?
Authors: Smith Peter G.R. , Tawy Goronwy , Bannerman Rex H. , Gawith Corin B.E. , Mennea Paolo , Davidson Noelia Palomar , Gates James C
Published: October 2024

Since the first demonstration of electric field poling in 1993 - by workers at Sony - periodically poled materials (e.g. PPLN) have become ubiquitous in photonics. Their ability to allow quasi-phase matching opens up nonlinear optics across the full transparency bands of a material. In the case of PPLN this spans from the visible out to around 5 microns – offering a powerful route to create light in spectral regions where convenient lasers do not exist. This talk will cover underlying physics, materials, design, manufacturing and applications, as well as looking at next generation applications.