title: A statistical modeling approach to computer-aided quantification of dental biofilm.
abstract: Biofilm is a formation of microbial material on tooth substrata. Several methods to quantify dental biofilm coverage have recently been reported in the literature, but at best they provide a semiautomated approach to quantification with significant input from a human grader that comes with the grader's bias of what is foreground, background, biofilm, and tooth. Additionally,human assessment indices limit the resolution of the quantification scale; most commercial scales use five levels of quantification for biofilm coverage (0%, 25%, 50%, 75%, and 100%). On the other hand, current state-of-the-art techniques in automatic plaque quantification fail to make their way into practical applications owing to their inability to incorporate human input to handle misclassifications. This paper proposes a new interactive method for biofilm quantification in Quantitative light-induced fluorescence(QLF) images of canine teeth that is independent of the perceptual bias of the grader. The method partitions a QLF image into segments of uniform texture and intensity called superpixels; every superpixel is statistically modeled as a realization of a single 2-D Gaussian Markov random field (GMRF) whose parameters are estimated; the superpixel is then assigned to one of three classes (background, biofilm, tooth substratum) based on the training set of data. The quantification results show a high degree of consistency and precision. At the same time, the proposed method gives pathologists full control to postprocess the automatic quantification by flipping misclassified superpixels to a different state (background,tooth, biofilm) with a single click, providing greater usability than simply marking the boundaries of biofilm and tooth as done by current state-of-the-art methods.
authors.forename: Awais
authors.initials: A
authors.lastname: Mansoor
authors.forename: Valery
authors.initials: V
authors.lastname: Patsekin
authors.forename: Dale
authors.initials: D
authors.lastname: Scherl
authors.forename: J Paul
authors.initials: JP
authors.lastname: Robinson
authors.forename: Bartlomiej
authors.initials: B
authors.lastname: Rajwa
mesh_terms: D000465:Algorithms; D018441:Biofilms / Q000254:growth & development*; D003198:Computer Simulation; D003481:Cuspid / Q000382:microbiology / Q000473:pathology*; D003773:Dental Plaque / Q000382:microbiology* / Q000473:pathology*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008856:Microscopy, Fluorescence / Q000379:methods; D015233:Models, Statistical; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity