DETECTION OF SIMULATED OSTEOPOROSIS IN HUMAN ANTERIOR MAXILLARY ALVEOLAR BONE WITH DIGITAL SUBTRACTION

The purpose of this in vitro study was to examine radiographic changes in human anterior maxillary alveolar bone during simulated osteoporos is (decalcification) and to determine the minimal amount of generalize d decalcifications that can be detected under optimal radiographic con ditions with the use of digital subtraction. Five samples of human ant erior maxillary alveolus were progressively decalcified at timed inter vals with 0.1 N hydrochloric acid solutions, and the percentage of cal cium lost during each interval was quantified with calcium assays. Set s of four radiographs were exposed at 70 kVp initially and after each decalcification interval. The radiographs were digitized and digitally filtered, and bone profiles (scan lines) were generated between selec ted points on lead markers. To further reduce corrupting film-grain no ise each set of four profiles were superimposed and averaged on a pixe l-by-pixel basis. The averaged profile from each stage of decalcificat ion was subtracted from the averaged initial profile on a pixel-by-pix el basis, and the mean profile intensity change for each decalcificati on stage calculated. Statistical analysis was performed with repeated measures analysis of variance. Results indicate that generalized decal cification less than or equal to 5.3% was detected in all samples of h uman anterior maxillae with the use of digital subtraction.