title: A comparison of 2 patient populations using fractal analysis.
abstract: This study was undertaken to demonstrate that the fractal dimensions calculated using digitized non-standardized, clinical radiographs of mandibular alveolar bone from a population of patients diagnosed with periodontitis are statistically different from fractal dimensions calculated from another population diagnosed as having gingivitis or healthy gingiva. The fractal dimension was calculated using a public domain fractal analysis program distributed by the National Institutes of Health (NIH). Fractal dimensions were calculated from digitized clinical radiographs for 29 patients diagnosed with healthy gingiva and/or gingivitis and 32 patients diagnosed with periodontitis and compared. To estimate the reproducibility of the technique, we recalculated the fractal dimension from images of the gingivitis patients 3 months after the original calculations and compared them to the originals. A 2 sample, 2-tailed Student t test showed the gingivitis data group to be different from the periodontitis data group (P = 0.0012). The original gingivitis and repeat gingivitis groups fractal dimension calculation were the same and analysis showed the two data sets were not significantly different (P = 0.99). We found that: 1) fractal dimensions could be used to distinguish between gingivitis and periodontitis patient groups; 2) fractal dimensions could be calculated from non-standardized clinical radiographs; and 3) fractal dimensions for gingivitis patients were reproducible over a 3-month period.
authors.affiliation: Oral Diagnosis and Patient Services, School of Dentistry, Medical College of Georgia, Augusta 30912-1241, USA. mshrout@mail.mcg.edu
authors.forename: M K
authors.initials: MK
authors.lastname: Shrout
authors.forename: B
authors.initials: B
authors.lastname: Roberson
authors.forename: B J
authors.initials: BJ
authors.lastname: Potter
authors.forename: J M
authors.initials: JM
authors.lastname: Mailhot
authors.forename: C F
authors.initials: CF
authors.lastname: Hildebolt
mesh_terms: D000328:Adult; D000539:Alveolar Process / Q000000981:diagnostic imaging*; D005260:Female; D005500:Follow-Up Studies; D017709:Fractals; D005881:Gingiva / Q000000981:diagnostic imaging*; D005891:Gingivitis / Q000000981:diagnostic imaging*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D009316:National Institutes of Health (U.S.); D010514:Periodontal Pocket / Q000000981:diagnostic imaging; D010518:Periodontitis / Q000000981:diagnostic imaging*; D017150:Public Sector; D019252:Radiography, Dental, Digital; D015203:Reproducibility of Results; D014481:United States