Radiographic absorptiometry method in measurement of localized alveolar bone density changes.
OBJECTIVE
The objective of this study was to measure the accuracy and precision of a radiographic absorptiometry method by using an occlusal density reference wedge in quantification of localized alveolar bone density changes.


METHODS
Twenty-two volunteer subjects had baseline and follow-up radiographs taken of mandibular premolar-molar regions with an occlusal density reference wedge in both films and added bone chips in the baseline films. The absolute bone equivalent densities were calculated in the areas that contained bone chips from the baseline and follow-up radiographs. The differences in densities described the masses of the added bone chips that were then compared with the true masses by using regression analysis.


RESULTS
The correlation between the estimated and true bone-chip masses ranged from R = 0.82 to 0.94, depending on the background bone density. There was an average 22% overestimation of the mass of the bone chips when they were in low-density background, and up to 69% overestimation when in high-density background. The precision error of the method, which was calculated from duplicate bone density measurements of non-changing areas in both films, was 4.5%.


CONCLUSIONS
The accuracy of the intraoral radiographic absorptiometry method is low when used for absolute quantification of bone density. However, the precision of the method is good and the correlation is linear, indicating that the method can be used for serial assessment of bone density changes at individual sites.
Kuhl
E D
ED
Department of Dental Diagnostic Science, University of Texas Health Science Center at San Antonio, USA.
Nummikoski
P V
PV
D015502:Absorptiometry, Photon; D000539:Alveolar Process / Q000000981:diagnostic imaging*; D001641:Bicuspid; D015519:Bone Density; D001842:Bone and Bones / Q000000981:diagnostic imaging; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008334:Mandible / Q000000981:diagnostic imaging; D008963:Molar; D011856:Radiographic Image Enhancement; D012044:Regression Analysis; D014962:X-Ray Film