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Objective: The aim of this study was to determine (1) the effect of various scan delays on pixel intensity measurements and (2) the diagnostic accuracy of occlusal caries detection. Methods: 72 non-cavitated extracted human permanent molar teeth with sound and carious occlusal surfaces were radiographed using the DIGORAH storage phosphor plates (SPPs) (Soredex Corporation, Helsinki, Finland). Plates were scanned immediately and 10 min, 30 min, 60 min and 120 min after exposure. Three different plates were used for each scan delay. An aluminium (Al) wedge was used to evaluate the change in mean grey values (MGVs) for scan delays. Diagnostic accuracy for occlusal caries detection was performed by scoring all the digital images. The true presence of caries was determined by stereomicroscopy. Comparison of MGVs of the Al wedge for immediate and delayed scans was made using repeated measures analysis of variance (ANOVA) and Tukey-Kramer tests. The accuracy was expressed as the area under the receiver operating characteristics curves (A z ). A z s were compared using two-way ANOVA and t-tests. Kappa was used to measure inter and intraobserver agreement. Results: The mean A z s of immediately scanned plates were higher than the A z s of plates scanned with four different delays (p , 0.05). The A z of immediately scanned images was significantly higher than the A z s of images with 60 min and 120 min scan delays (p , 0.05) but not for 10 min and 30 min delays (p . 0.05). MGVs of immediately scanned plates were significantly higher than the plates scanned with four different delays (p , 0.05). Agreement decreased with increasing scan delays. Conclusion: Scanning of DIGORA SPPs should not be delayed beyond 30 min for accurate occlusal caries diagnosis.

The MIC and LF are associated with neurovascular bundle variations in number, location and size. Therefore, clinicians should determine each of these anatomical structures on a case-by-case basis to recognize their presence and to take measures for the possible implications of various treatment options. These guidelines included leaving a 2 mm safety zone between an implant and the coronal aspect of the neurovascular bundle. To avoid neurovascular injury during surgery in the interforaminal area, guidelines were developed with respect to validating the presence of an anterior loop of the neurovascular bundle.

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Objectives: The aims of the study were to compare subjective image quality of clinical images obtained with a storage phosphor plate (SPP)-based digital and conventional filmbased panoramic system for the visualization of various anatomical structures and to evaluate the effect of various processing algorithms on image interpretation. Methods: Panoramic radiographs were taken in 42 patients both with film and with a SPP system. SPP images were treated with shadow, sharpen, negative, greyscale sigma and greyscale exponential filters. Four observers subjectively evaluated films and unfiltered and filtered SPP images for the visibility of anatomical structures with various radiodensities as well as for overall image quality on a three-point rating scale. The statistical methods used were Kruskal-Wallis, odds ratio analysis and Cohen's kappa. Results: No statistically significant difference was found between film and unfiltered digital images except for low-contrast structures (P . 0.05). Film images were preferred for the visibility of low-contrast structures (P , 0.05). Best overall image quality was obtained with sharpened images (P , 0.05) followed by films and unfiltered digital images. Among all filtered images, sharpened ones received the highest ratings for the visibility of all anatomical structures (P , 0.05). The intra-and interobserver agreement ranged between moderate and substantial and between fair and moderate, respectively. Conclusions: Film and unfiltered SPP-based panoramic images performed equally well in terms of overall quality; however, films were best for the perception of low-contrast structures. The sharpening filter may be recommended for enhancing SPP panoramic images to improve the visual perception of most of the anatomical structures as well as overall quality.