| 1. |
- Geraets, Wil Gm, et al.
(författare)
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Changing trabecular patterns in panoramic radiographs of Swedish women during 25 years of follow-up.
- 2020
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Ingår i: Dento maxillo facial radiology. - 0250-832X. ; 49:6
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Tidskriftsartikel (refereegranskat)abstract
- The radiographic trabecular pattern on dental radiographs may be used to predict fractures. The aim of this study was to analyze longitudinal changes in the mandibles of 145 females between 1980 and 2005.Panoramic radiographs were obtained in 1980 and 2005. On 290 radiographs, regions of interest (ROIs) were selected in the ramus, angle and body. In all ROIs, the orientation was measured in 36 directions with the line frequency deviation method. The effects of ageing were analyzed for the fracture and the non-fracture groups separately.During the follow-up, 61 females suffered fractures of the hip, wrist, spine, leg or arm. The fracture and non-fracture groups displayed dissimilar age changes in each investigated ROI. All significant changes pertained to increasing values of line frequency deviation. With increasing age, the trabecular network in the mandible lost details and the trabeculae became more aligned in their main direction. In the "ramus", the alignment was to the 110-120˚ axis, parallel to the posterior and anterior ramus border. In the "angle", the alignment was to the 135-150˚ axis, parallel to the oblique line, and in the "body" ROI to the 150-175˚ direction, approximately parallel to the occlusal plane and inferior cortex.Most changes were consistent with the notion that the bone aged less severely in the non-fracture group. In the fracture group, the findings indicate that bone loss leads to redistribution of the remaining bone tissue in such a way that the trabeculae are accentuated perpendicular to the principal loading.
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| 2. |
- Geraets, Wil G, et al.
(författare)
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Osteoporosis and the general dental practitioner : reliability of some digital dental radiological measures
- 2007
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Ingår i: Community Dentistry and Oral Epidemiology. - : Wiley. - 0301-5661 .- 1600-0528. ; 35:6, s. 465-471
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: Dental radiographs are relatively inexpensive and are regularly made of a large fraction of the adult population; therefore, they represent an enormous potential as a screening tool for osteoporosis. Monitoring the population by means of dual X-ray absorptiometry (DXA), which is currently the most accepted method for diagnosing osteoporosis, involves enormous costs and facilities. In previous studies, it was shown that the radiographic trabecular pattern shows correlations with the bone mineral density (BMD) as measured by DXA. The objective of this study was to assess the reproducibility of the quantitative analysis of the trabecular pattern on dental radiographs. METHODS: Six regions of interest were selected manually on three digital radiographic images of 20 women. This process was performed 10 times resulting in 1200 image samples. For each image sample 26 parameters were measured. The reliability of the parameters was evaluated by means of Cronbach's alpha. RESULTS: Of the values of Cronbach's alpha 83% is at least 0.9 and 99% is at least 0.8. CONCLUSIONS: The measurements of the parameters used in this study are very reproducible. Therefore, the manual selection of the regions of interest does not introduce large amounts of noise. The imaging parameters potentially offer an accurate tool for the prediction of BMD values. PMID: 18039288 [PubMed - in process]
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| 3. |
- Geraets, Wil G, et al.
(författare)
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Prediction of bone mineral density with dental radiographs
- 2007
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Ingår i: Bone. - : Elsevier BV. - 8756-3282 .- 1873-2763. ; 40:5, s. 1217-1221
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Tidskriftsartikel (refereegranskat)abstract
- There is consensus to use the bone mineral density (BMD) for the operational definition of the degree of osteoporosis and the risk of osteoporotic fractures. Dual X-ray absorptiometry (DXA) is the common technique to determine BMD. Because of high costs and limited availability of DXA equipment it is worthwhile to look for alternative diagnostic techniques. As part of a larger study, the Osteodent project, we investigated if the trabecular pattern on dental radiographs can be used to predict BMD and to identify the subjects with osteoporosis and increased risk of osteoporotic fractures. In four clinical centers 671 women with an average age of 55 years were recruited. BMD values were measured by DXA equipment at the femoral neck, total hip, and spine. One panoramic and two intraoral radiographs were made. From 525 women a complete set of BMD values and radiographs was obtained. Four regions of interest on the radiographs were selected manually and then processed automatically. On all regions of interest mean and standard deviation of the gray values were measured and several features describing the shape of the binarized trabecular pattern. Multiple regression was used to predict BMD of total hip and spine by means of the radiographic measurements combined with age. It was found that age accounts for 10% of the variation in total hip BMD and 14% of the variation in spinal BMD. When all measurements on the dental radiographs are used the explained variation increases to 22% and 23%. The areas under the ROC curves are comparable to those of commonly used screening instruments for osteoporosis. It is concluded that prediction of DXA measurements of BMD by means of quantitative analysis of the trabecular pattern on dental radiographs is feasible. PMID: 17317351 [PubMed - indexed for MEDLINE]
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| 4. |
- Geraets, Wil GM, et al.
(författare)
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Selecting regions of interest on intraoral radiographs for the prediction of bone mineral density
- 2008
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Ingår i: Dento-Maxillo-Facial Radiology. - : Oxford University Press (OUP). - 0250-832X .- 1476-542X. ; 37:7, s. 375-379
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: A previous study showed that the trabecular pattern on dental radiographs correlates with femoral and spinal bone mineral density (BMD). The objective of this study was to determine if the correlation is affected by the size and location of the region of interest (ROI). METHODS: In a European research project on osteoporosis, BMD was measured at the left hip and the lumbar spine of 525 women. From all subjects, intraoral radiographs were made of the premolar region in the upper and lower jaws. Two ROIs were indicated manually on each scanned image. The smallest region involved only trabecular bone and the largest also included parts of the neighbouring teeth. The ROIs were subjected to automatic image analysis, yielding 26 measurements per ROI. Stepwise linear regression was used to predict femoral and spinal BMD. RESULTS: Inner and outer regions predicted BMD equally well. The radiographs of lower and upper jaw also predicted BMD equally well. Combining inner and outer regions did not improve the prediction of femoral and spinal BMD, but combining lower and upper jaws did. CONCLUSIONS: This study shows that it is possible to include parts of neighbouring teeth in the ROI used to assess the trabecular pattern and predict BMD. This simplifies the process of selecting the ROIs because no efforts have to be made to exclude neighbouring teeth. Combining ROIs of lower and upper jaws significantly improves the prediction of BMD.
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| 5. |
- Geraets, Wil, et al.
(författare)
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Predicting fractures using trabecular patterns on panoramic radiographs.
- 2018
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Ingår i: Clinical oral investigations. - : Springer Science and Business Media LLC. - 1436-3771 .- 1432-6981. ; 22:1, s. 377-384
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Tidskriftsartikel (refereegranskat)abstract
- The observer score of the trabecular pattern on panoramic radiographs is known to be a strong predictor of bone fractures. The aim of this study was to enhance the predictive power of panoramic radiographs by means of texture analysis methods.The study followed 304 postmenopausal women during 26 years. At the beginning of the study, panoramic radiographs were obtained. One observer assessed the trabecular pattern in the premolar region as dense, sparse, or alternating dense and sparse. In addition, on each radiograph, a region of interest was selected in the molar/premolar region and analyzed with texture analysis procedures. During 26years of follow-up, 115 women suffered a fracture of the hip, spine, leg, or arm. Logistic regression was applied to test the predictive power of various variables with respect to fractures.Of all variables, the observer score of the trabecular pattern correlated strongest with the occurrence of fractures. By itself, the score yielded an ROC curve with an area of 0.80 under the curve. Combining the observer score with the texture analysis features increased the area under the ROC curve to 0.85.The trabecular pattern on panoramic radiographs provides a strong predictor of fractures, at least for postmenopausal women. The assessment by an observer combined with texture analysis procedures yields a predictive power that parallels best known predictions in literature.This study illustrates that panoramic radiographs are state of the art predictors of postcranial fractures.
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| 6. |
- Geraets, Wil, et al.
(författare)
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Sparseness of the trabecular pattern on dental radiographs : visual assessment compared with semi-automated measurements
- 2012
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Ingår i: British Journal of Radiology. - : British Institute of Radiology. - 0007-1285 .- 1748-880X. ; 85:1016, s. e455-e460
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Tidskriftsartikel (refereegranskat)abstract
- Abstract OBJECTIVE: In diagnostic imaging; human perception is the most prominent, yet least studied, source of error. A better understanding of image perception will help to improve diagnostic performance. This study focuses on the perception of coarseness of trabecular patterns on dental radiographs. Comparison of human vision with machine vision should yield knowledge on human perception. METHOD: In a study on identifying osteoporotic patients, dental radiographs were made from 505 post-menopausal women aged 45-70 years. Intra-oral radiographs of the lower and upper jaws were made. Five observers graded the trabecular pattern as dense, sparse or mixed. The five gradings were combined into a single averaged observer score per jaw. The radiographs were scanned and a region of interest (ROI) was indicated on each. The ROIs were processed with image analysis software measuring 25 image features. Pearson correlation and multiple linear regression were used to compare the averaged observer score with the image features. RESULTS: 14 image features correlated significantly with the observer judgement for both jaws. The strongest correlation was found for the average grey value in the ROI. Other features, describing that osteoporotic patients have fewer but bigger marrow spaces than controls, correlated less with the sparseness of the trabecular pattern than a rather crude measure for structure such as the average grey value. CONCLUSION: Human perception of the sparseness of trabecular patterns is based more on average grey values of the ROI than on geometric details within the ROI.
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| 7. |
- Verheij, Johannes GC, et al.
(författare)
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Prediction of osteoporosis with dental radiographs and age
- 2009
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Ingår i: Dento-Maxillo-Facial Radiology. - : British Institute of Radiology. - 0250-832X .- 1476-542X. ; 38:7, s. 431-437
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: In this study age and the trabecular pattern present on dental radiographs were used to predict the presence of osteoporosis. The objective was to evaluate the contribution of the trabecular pattern to the prediction. METHODS: In this project, 671 women between 45 and 71 years of age were recruited. Medical history was obtained and dental radiographs were made. Bone mineral density (BMD) was measured at three sites to assess the presence of osteoporosis according to the World Health Organization criteria. The radiographs were subjected to image analysis methods yielding measurements of the trabecular pattern. Thereafter, discriminant analysis was used to predict the presence of osteoporosis by means of the trabecular pattern and age. Sensitivity and specificity of age and the trabecular pattern were compared. Also, it was checked whether the inclusion of the trabecular pattern improved the sensitivity and specificity that were obtained when only age was used as the predictor. RESULTS: The sensitivity and specificity of the trabecular pattern present on dental radiographs were almost equal to those of age. However, combining age with the trabecular pattern increased the sensitivity from 0.71 to 0.75 and the specificity from 0.72 to 0.78; the latter increase was statistically significant. CONCLUSIONS: The trabecular pattern predicts the presence of osteoporosis just as well as age does. When combining the trabecular pattern with age, the sensitivity and specificity increased. Only the latter increase was statistically significant.
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