Detecting Reduced Bone Mineral Density From Dental Radiographs Using Statistical Shape Models

Abstract

We describe a novel method of estimating reduced bone mineral density (BMD) from dental panoramic tomograms (DPTs), which show the entire mandible. Careful expert width measurement of the inferior mandibular cortex has been shown to be predictive of BMD in hip and spine osteopenia and osteoporosis. We have implemented a method of automatic measurement of the width by active shape model search, using as training data 132 DPTs of female subjects whose BMD has been established by dual-energy X-ray absorptiometry. We demonstrate that widths measured after fully automatic search are significantly correlated with BMD, and exhibit less variability than manual measurements made by different experts. The correlation is highest towards the lateral region of the mandible, in a position different from that previously employed for manual width measurement. An receiver-operator characterstic (ROC) analysis for identifying osteopenia (T < -1: BMD more than one standard deviation below that of young healthy females) gives an area under curve (AUC) value of 0.64. Using a minimal interaction to initiate active shape model (ASM) search, the measurement can be made at the optimum region of the mandible, resulting in an AUC value of 0.71. Using an independent test set, AUC for detection of osteoporosis (T < -2.5) is 0.81.

Panoramic Measures for Oral Bone Mass in Detecting Osteoporosis

“…Two of the retrieved studies (Gulsahi et al 2009;Gulsahi et al 2010) were grouped together, since they refer to the same population; therefore, we finally considered 50 studies for the qualitative assessment. Five studies (Devlin et al 2007;Horner et al 2007;Karayianni et al 2007;Roberts et al 2010;Roberts et al 2013) referred to the same multicenter study (OSTEODENT), but each focused on different indices or different techniques of index calculation and therefore were considered as separate studies. The same approach was followed for the studies by Lee et al (2005), Arifin et al (2006), and Nakamoto et al (2003).…”

The role of the dental surgeon in detecting osteoporosis: the OSTEODENT study

“…Hip frac tures, in particular, are associated with significant mortality and morbidity in the elderly, 1 but in one study, less than one fifth (18%) of high risk peo ple had received medical treatment for osteoporosis before the occurrence of hip fracture. 2 The current failure to assess and treat patients at high risk of osteoporosis may be partly due to 1* School of Dentistry, University of Manchester; 2,3,7,8 Im aging Science and Biomedical Engineering, University of Manchester; 4 Oral Imaging Centre, Katholieke Uni versiteit, Belgium; 5 Oral Diagnosis and Radiology, Den tal School of Athens; 6 Faculty of Odontology, Malmo University, Sweden; 9,11 School of Dentistry, University of Manchester; 10 insufficient resources or time, but a failure of health professionals to iden tify risk factors and refer the patient for defi nitive diagnosis using dual-energy X-ray absorptiometry (DXA) is an important contributory factor.…”

“…We propose a strategy of the dentist referring individuals with a thin mandibular cortex and other clini cal risk factors for further DXA inves tigation. Detection of a thinned cortex on DPRs using specially developed com puter software 8 has been found to be a good predictor of systemic osteoporosis, and because the method is automatic it is also convenient.…”

Early diagnosis of osteoporosis by means of orthopantomograms and oral x-rays: A systematic review

“…In addition, in the OSTEODENT project, in 2007, Devlin et al (17) used the measurements of the mandibular cortical thickness (MCT) and visual assessment of the cortical bone, concluding that patients who obtained measurements of the cortical thickness < 3 mm must be referred for subsequent studies to determine whether or not there is a presence of osteoporosis. As part of the OSTEODENT project, in 2008, Devlin et al (18) used an automatic system in panoramic X-rays in order to detect the thickness of the cortical bone, as described by Allen et al (19), combined with the OSIRIS rates of risk, concluding that dentists play an essential role in the initial detection of patients with a high risk factor for developing osteoporosis.…”