title: Analysis of changes in gingival contour from three-dimensional co-ordinate data in subjects with drug-induced gingival overgrowth.
abstract: OBJECTIVE
  This aim of this study was to develop and assess a technique that could be used to assess accurately the gingival volume changes seen in drug-induced gingival overgrowth by the analysis of data obtained from an entire gingival surface by means of three-dimensional imaging.
  
  
  METHODS
  Stone dental models of patients before and after gingivectomy procedures were digitized with a laser scanner and then regenerated as computer models constructed from the acquired three-dimensional co-ordinate data. A comparison of superposed "before" and "after" surfaces was undertaken to assess and accurately quantify changes in gingival contour.
  
  
  RESULTS
  The mean vertical tissue reduction varied from 1.58 to 2.56 mm in the four study subjects and individual differences are shown. The maximum thickness of removed buccal gingival overgrowth was found to range between 1.20 and 3.40 mm. The volume of tissue removed from each inter-dental papilla ranged from 4.2 to 46.1 mm3 and the mean volume of the papilla removed from each subject+/-SD values was 24.8+/-13.1 mm3.
  
  
  CONCLUSIONS
  This method will measure changes in gingival tissues to within 60 microm in one plane, making it ideal for the assessment of longitudinal changes in gingival contour as seen in the development of gingival overgrowth, its recurrence after surgery or the changes in volume brought about by surgery.
authors.affiliation: School of Dental Sciences, University of Newcastle upon Tyne, Framlington Place, Newcastle upon Tyne NE2 4BW, UK. j.m.thomason@newcastle.ac.uk
authors.forename: J M
authors.initials: JM
authors.lastname: Thomason
authors.forename: J S
authors.initials: JS
authors.lastname: Ellis
authors.forename: V
authors.initials: V
authors.lastname: Jovanovski
authors.forename: M
authors.initials: M
authors.lastname: Corson
authors.forename: E
authors.initials: E
authors.lastname: Lynch
authors.forename: R A
authors.initials: RA
authors.lastname: Seymour
mesh_terms: D005881:Gingiva / Q000473:pathology*; D019214:Gingival Overgrowth / Q000139:chemically induced / Q000473:pathology*; D005890:Gingivectomy; D006801:Humans; D007091:Image Processing, Computer-Assisted; D003765:Models, Dental; D010672:Phenytoin; D010865:Pilot Projects
chemical_list: D010672:Phenytoin