Service Communautaire d'Information sur la Recherche et le Développement - CORDIS

FP5

OSTEODENT Résumé de rapport

Project ID: QLK6-CT-2002-02243
Financé au titre de: FP5-LIFE QUALITY
Pays: Belgium

Accuracy and precision of a densitometric tool for jaw bone: in vitro study

A densitometric tool for jaw bone to analyse intraoral radiographs was developed. It consisted of custom made bite blocks, including an aluminium wedge for reference. Also, software to analyse the radiographs taken with this tool was developed and optimised.

Precision, accuracy and minimal detection threshold for the analyses of intraoral radiographs were assessed. Methods: Bone samples deriving from the premolar region of 47 human mandibles were selected for analysis. The samples were obtained from adult cadavers in the department of anatomy (Faculty of Medicine, KULeuven) with ethical approval. Digital radiography was performed on all bone samples. Direct volumetric measurements served as gold standard density values and allowed determination of accuracy. DXA scans were performed on all specimens.

For all radiographs, density in mm Al eq was calculated using a custom-made software, Osteop. Precision and intra- and interobserver reliability of this method was assessed. The bone specimens were progressively decalcified. At standard time intervals the percentage of decalcification was calculated. At each decalcification step, radiographs were taken and analyzed.

All radiographs were also analysed, not using the wedge, but the average pixelvalue of the background-colour as a reference. This was done as to be able to detect the advantage of including the wedge.

Results: CV was always lower then 3%, which points to a good precision of the method. Correlation between the density measurements in mm Al eq and the DXA results was .9, for the density measurements in mm Al eq and the direct density measurements r was .5. The custom-made software was able to detect a change in bone mineralization of 6.6%.

The densitometric measurements with only the average pixelvalue of the background-colour as a reference, were not significantly correlated with the DXA-results.
Conclusions: The present method for bone densitometric analysis offers potentials for clinical evaluation of bone density and minute bone density changes in the jaw bone. It was proven to be a superior method, compared to purely analysing pixel values.

The densitometric tool was found to be a valid tool to measure bone density on intraoral radiographs. Therefore it was suitable to perform measurements on the large sample of intraoral radiographs collected in the Osteodent project.

Contact

Reinhilde JACOBS, (Professor)
Tél.: +32-16-332410
Fax: +32-16-332484
E-mail