title: Distribution of different morphologic types of subgingival calculus on proximal root surfaces.
abstract: OBJECTIVE
  To evaluate the distribution of morphologic types of subgingival calculus at different parts of the proximal root surface.
  
  
  METHODS
  Ninety extracted teeth from 29 chronic periodontitis patients were collected. The mean pocket depths and periodontal attachment levels of the extracted teeth were 5.93 +/- 1.51 mm and 7.82 +/- 1.75 mm, respectively. The proximal root surfaces below the gingival margin were divided into three parts in an apicocoronal direction, and each of these portions was further divided into three parts in a buccolingual direction. Subgingival calculus present was classified as: 1 = crusty, spiny, or nodular; 2 = ledge or ring; 3 = thin, smooth veneers; 4 = finger- or fernlike; 5 = individual calculus islands/spots; or 6 = supramarginal upon submarginal deposits. The distribution of different morphologic types of subgingival calculus on each division of the mesial and distal proximal root surfaces was evaluated with a magnifier.
  
  
  RESULTS
  Regardless of the morphologic type, calculus deposits were observed at around 30% of proximal root surfaces. The coronal thirds of the root surfaces were found to have significantly more calculus deposits than the middle thirds (P < .05). In general, it was observed that most of the deposits were of the thin, smooth veneer type on all root surfaces.
  
  
  CONCLUSIONS
  Within the limits of this study, the distribution of various calculus types was similar on different parts of the root surface; however, calculus was found more frequently on the coronal thirds than on the more apical regions.
authors.affiliation: Department of Periodontology, Ankara University Faculty of Dentistry, Ankara, Turkey. dentfam25@hotmail.com
authors.forename: Cem A
authors.initials: CA
authors.lastname: Gürgan
authors.forename: Evren
authors.initials: E
authors.lastname: Bilgin
mesh_terms: D000328:Adult; D000368:Aged; D016009:Chi-Square Distribution; D003728:Dental Calculus / Q000145:classification / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018709:Statistics, Nonparametric; D014092:Tooth Root / Q000473:pathology*