title: Fractal dimension from radiographs of peridental alveolar bone. A possible diagnostic indicator of osteoporosis.
abstract: The purpose of this study was to investigate whether a radiographic estimate of osseous fractal dimension is useful in the characterization of structural changes in alveolar bone. Ten dry mandibular bone segments were radiographed from three controlled projection angles (-5, 0, +5 degrees), before and after acid-induced partial decalcification. Fractal dimension was estimated by regression analysis of power spectra computed by Fourier transform of selected regions of interest in digitized images of the radiographs. Repeated-measures ANOVA showed that fractal dimension so determined varied over anatomic locations (p less than .01), but increased after acid-induced demineralization (p less than .0005), irrespective of the radiographic projection angles (p greater than .99). In vivo fractal dimension was computed from randomly selected intraoral radiographs of six premenopausal (ages, 32.8 +/- 3.9) and six postmenopausal (ages, 62.5 +/- 4.1) women. A significantly (p less than .01) higher fractal dimension was observed in the older group.
authors.affiliation: Diagnostic Systems Branch, National Institute of Dental Research, National Institutes of Health, Bethesda, Md.
authors.forename: U E
authors.initials: UE
authors.lastname: Ruttimann
authors.forename: R L
authors.initials: RL
authors.lastname: Webber
authors.forename: J B
authors.initials: JB
authors.lastname: Hazelrig
mesh_terms: D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging*; D000539:Alveolar Process / Q000000981:diagnostic imaging*; D000704:Analysis of Variance; D015519:Bone Density; D003648:Decalcification Technique; D005260:Female; D005583:Fourier Analysis; D006801:Humans; D008334:Mandible / Q000000981:diagnostic imaging; D008433:Mathematics; D008875:Middle Aged; D010024:Osteoporosis / Q000000981:diagnostic imaging*; D015663:Osteoporosis, Postmenopausal / Q000000981:diagnostic imaging; D010363:Pattern Recognition, Automated; D011856:Radiographic Image Enhancement / Q000379:methods*; D011857:Radiographic Image Interpretation, Computer-Assisted; D012044:Regression Analysis; D013053:Spectrophotometry