ABSTRACT
In osteoporotic patients, inferior mandibular cortex undergoes resorption which its manifestations can be detected on dental panoramic radiographs as a simple and available method. The aim of this study was to evaluate the correlation between width and morphology of mandibular inferior cortex in digital panoramic radiography and postmenopausal osteoporosis. Bone mineral density [BMD] of lumbar vertebrae and femoral neck of 119 postmenopause women was assessed using DXA. Width [cortical index [CI]] and morphology [mandibular cortical index [MCI] of inferior mandibular cortex were measured and the correlations between BMD and width and shape of the inferior mandibular cortex were evaluated. The specificity and sensitivity in identifying women with low BMD of lumbar vertebrae by visual cortical estimation [normal or eroded] were 69.4% and 80.7% respectively. These results in identifying women with low BMD of femoral neck were 67.7% and 81.5% respectively. For both sides, the threshold value that provided the highest validity [minimal false negative and false positive results] corresponded to cortical width of 4.29 mm. This threshold in lumbar vertebrae or femoral neck provided a sensitivity of 81.4% [95% CI=69.1%-90.3%], specificity of 58.3% [95% CI=44.9%-70.9%], positive predictive value of 65.8% and likelihood ratio of 1.95. There were significant associations between BMD and CI and MCI. Postmenopausal women with thin or eroded mandibular inferior cortex may have an increased risk for low BMD or osteoporosis
Subject(s)
Humans , Female , Radiography, Panoramic , Mandible/diagnostic imaging , Bone DensityABSTRACT
Today, the most precise method for TMJ soft tissue imaging is MRI. But, due to high cost and complexities of this procedure, its application to all patients is neither possible, nor logical. So, many physicians are forced to treat their involved patients in TMJ dysfunction, without complete information about disc situation, based only on the results of clinical exams and evidences of conventional radiography of TMJ hard tissues. The aim of this study is to evaluate the accuracy of the high resolution-Ultra sonography [HRUS] in TMJ disc displacement detection. This is done via the evaluation of the "false positive internal joint derangement" in sonography by using MRI. MRI imaging of 16 TMJs of 10 patients, which in clinical exams were diagnosed as ADD [Anterior Disc Displacement] cases, was confirmed by sonography. The results of sonography compared with those of MRI were tabulated [table 1]. The final results presented descriptively. In this study, all cases of ADD diagnosed in sonography, were confirmed by MRI too. HR-US can be used in TMJ diagnosis and treatment planning as a reliable technique for imaging of disc in this joint
ABSTRACT
Statement of Problem: One of the difficulties that a dentist encounter during root canal treatment is the cleaning and shaping of curved root canals. While doing this procedure the probability of zipping, perforation, apical transportation and canal curvature change increases that all of those are the result of not following the original root canal path by the file. This will fail the prognosis of root canal treatment
Purpose: This in vitro study was undertaken to evaluate the effects of a hand and a rotary instrumentation technique [passive step back and profile system] on canal curvature of mesial roots of human extracted molar teeth
Materials and Methods: In this experimental study, 40 mesial roots of first molar teeth with [20-40 degree] curvature were used. The roots were divided randomly into two groups of 20 and the canals were prepared by a hand instrumentation technique [passive step-back] and a rotary [profile system]. Pre and post instrumentation radiographs were taken by radiographic platform. The amounts of alteration in canal curvature were measured by the aid of Adobe Photoshop 7 and Auto CAD 2000 software. Results were analyzed using Man Whitney test
Results: After instrumentation, canal curvature showed 85% reduction in passive-step back and 65% in profile system experimental groups. Mean canal curvature reduction in passivestep back was 3.15+1.94 while in profile system was 1.85+1.67. There was statistically significant difference between two experimental groups [p<0.05]
Conclusion: Under the condition of this study, it seems that better maintenance of the original canal curvature in profile systems was due to the difference, between the properties of Niti and Stainless steel files
ABSTRACT
Statement of Problem: Dental caries is the most common chronic infectious diseases involving about 95% of population and still is a major cause of loss of teeth. Dental caries diagnosis is a challenging task for dental practitioners. In spite of developing different diagnostic methods for better evaluation of dental caries, conventional intraoral films continues to be the most widely used radiographic modality for the diagnosis of dental caries
Purpose: The aim of this study was to evaluate the efficiency of Ekta speed plus, insight radiographic films, and RVG ui 100 in detecting proximal caries lesions
Materials and Methods: Seventy two surfaces of 36 extracted human premolars were evaluated. Radiographs of teeth blocks were taken with two different films and RVG, under standard conditions. The presence or absence of approximal caries was evaluated by six observers according to 3 points confidence scale. The actual status of each surface of the tooth was histologicaly determined from the teeth sections. Sensitivity and specificity of the imaging modalities were calculated and the observer responses were assessed with Fissure Exact Test
Results: The sensitivity values of Ekta speed plus, Insight and RVG were 24.3%, 18% and 46% respectively, while the specificity values were 86.4%, 87.1% and 78% respectively. The difference in detecting approximal carious lesions between the systems was not statistically significant
Conclusion: This study suggests that there is no significant difference between the three imagining modalities in detecting approximal caries. So, Insight film and RVG ui sensor merit considerations as the new standard of care