Identifying risk groups for osteoporosis by digital panoramic radiography

Evaluation of mandibular bone density in bruxers: the value of panoramic radiographs

OBJECTIVES

This study aimed to establish a difference in mandibular bone density between bruxer and non-bruxer patients, based on panoramic radiographs.

METHODS

Panoramic radiographs of bruxer and non-bruxer patients were analyzed with ImageJ^®. Several radiological determinants were studied on the patients' panoramic radiographs: gray values of cancellous bone and cortical bone, and bony exostoses at the mandibular angle.

RESULTS

Thirty-seven bruxers and forty-seven non-bruxers were included in the study. A statistically significant difference (p < 0.05) was noted in the cancellous to cortical bone ratios of bruxers and non-bruxers: the density of cancellous bone was greater in bruxers than in non-bruxers. The number of bony exostoses at the mandibular angle was significantly higher in bruxers (p < 0.05).

CONCLUSIONS

This study obtained radiological determinants of bruxism from panoramic radiographs. Further studies are needed to supplement this preliminary approach, especially via the analysis of three-dimensional imaging to overcome the limitations of panoramic radiography.

The 2nd Metacarpal Cortical Index as a Simple Screening Tool for Osteopenia

Background

Osteopenia is a known risk factor for sustaining skeletal fractures. Prevention of fragility fractures has obvious clinical and economic advantages, however screening all patients using a dual energy X-ray absorptiometry (DXA) is controversial not only because of the cost implications but also because it would potentially involve exposing a percentage of normal patients to unnecessary radiation. We wished to assess whether a simple hand X-ray measuring the 2nd metacarpal cortical index (2MCI) could be used as a simple screening tool for identifying patients with osteopenia.

Methods

We retrospectively collected the radiographic data of 206 patients who had a simple radiograph of the hand and a DXA scan within one year of each other from our picture archiving and communication system database. The 2MCI was calculated for all patients. As data was parametric, a Pearson’s correlation was performed to assess association between T-scores and 2MCI. Further analysis involved the construction of receiver operating characteristic (ROC) curves to identify a 2MCI index, which would give the most appropriate sensitivity and specificity values for identifying the presence of osteopenia.

Results

A statistically significant and moderate correlation between DXA T-scores and 2MCI values was found (r=0.54, n=206, P<0.001). Further ROC curve analysis of normal and osteopenic subjects identified that a 2MCI of 41.5 had a sensitivity of 100% and specificity of 53% for detecting osteopenia.

Conclusions

Our results support the use of the 2MCI as a simple screening tool for identifying patients with osteopenia.

Relationship between Two Panoramic Radiography Indices and Bone Mineral Density of Postmenopausal Women with Osteopenia and Osteoporosis

STATEMENT OF THE PROBLEM

Reduced bone mineral density (BMD) generally affects postmenopausal women and it is classified into moderate (osteopenia) and significant osteoporosis. Based on digital panoramic radiographs (DPRs), several quantitative and qualitative assessment methods have been proposed for the diagnosis and evaluation of bone changes and as a predictor of BMD.

PURPOSE

The aim of this study was to compare mandibular cortical width (MCW) and mandibular cortical index (MCI) derived from DPRs in evaluating the BMD in osteopenic and osteoporotic post-menopausal women.

MATERIALS AND METHOD

In this cross-sectional study, the BMD assessment was performed using dual-energy X-ray absorptiometry (DEXA). Then, patients were divided into two groups: osteopenia and osteoporosis based on WHO criteria. Two types of T-scores including TT (trabecular) for lumbar spine, TC (cortical) for femoral neck and finally, MCW and MCI were measured based on DPRs.

RESULTS

Fifty females with the average age of 57.64±6.03 years were entered into the study. MCW significantly correlated with BMD (p< 0.05). Pearson correlation coefficient test revealed that there was almost significant relationship between MCI and BMD (p= 0.079). The area under the curve (AUC) in ROC suggested that there was a close overlap between MCW (0.773) and TC (0.783), but TT had the greatest AUC (0.996).

CONCLUSION

The results showed that MCW is an appropriate index of osteoporosis in post-menopausal women. Although the prediction of osteoporosis is poorer at the femoral neck than lumbar spine, MCW can serve as a screening tool for osteoporosis in this area.

Panoramic radiographs and quantitative ultrasound of the radius and phalanx III to assess bone mineral status in postmenopausal women

Background

Various mandibular indices have been developed to detect osteoporosis on panoramic radiographs. Quantitative ultrasound (QUS) is a low-cost, radiation-free method to assess bone status. The aim of this study was to compare mandibular morphometric analysis and QUS at the radius and proximal phalanx III finger.

Methods

The study involved 97 postmenopausal women, aged 48.5–71.5y (mean: 55.4). Mandibular morphometric analysis comprised: distance between upper and lower mandibular borders just behind the mental foramen (H), distance: mental foramen - inferior mandibular cortex (IM) and mandibular cortical width at the mental region (MCW). Then, ratios were calculated: MCW/IM = PMI (panoramic mandibular index), H/IM = MR (mandibular ratio). Mandibular cortical index (MCI) was used to classify the morphology of the mandibular cortex.

Bone mineral status assessed using QUS at the radius and proximal phalanx III finger was compared to population mean apical bone mass (T-score).

Linear regression analysis was used for correlations between continuous variables, Pearson’s correlation coefficient r - for variables of normal distribution. Student’s t-test was used to compare variables of normal distribution and for the latter - Mann-Whitney U-test. The level of significance was p < 0.05.

Results

Mandibular height was 13.42–34.42 mm. The mean mandibular cortical width was 3.31 mm. Mean values of PMI and MR were 0.33 and 2.57, respectively. Higher mean value of Ad-SoS was found in the radius than in the III finger. Phalanx T-score values ​​were lower than those of the radius. T-score of the radius was < − 1.0 in 22 patients, indicating osteopenia. Basing on phalanx T-score, osteopenia was found in 39 patients. Category C1 of Mandibular Cortical Index was found in 48 women, C2 - in 37 women and C3 - in 12 women. Higher scores of Mandibular Cortical Index were recorded in older women. MCI significantly correlated with the skeletal status (p = 0.01) as well as with H, MCW and MR. Phalanx T-score was not correlated to PMI, MR or MCW.

Conclusions

1. Mandibular Cortical Index can be used as a screening tool for detecting osteoporosis.

2. Quantitative ultrasound at the phalanx III constitutes a reliable way of assessing bone status.

Electronic supplementary material

The online version of this article (10.1186/s12903-018-0593-4) contains supplementary material, which is available to authorized users.