title: Root resorption in retained deciduous canine and molar teeth without permanent successors in patients with severe hypodontia.
abstract: OBJECTIVE
  The ability to predict the morbidity of retained deciduous teeth with no permanent successors, a characteristic of hypodontia, would be of considerable value in treatment planning, but is hampered by lack of data.
  
  
  METHODS
  This problem was studied using 356 orthopantomogram radiographs (OPGs) from the records of 249 patients who had attended a specialist hypodontia clinic, and had retained deciduous teeth with no permanent successors. Due to their clinical importance, canine and molar teeth were chosen for examination. Resorption was assessed subjectively by three experienced clinicians.
  
  
  RESULTS
  Un-weighted Kappa values for reproducibility were > 0.8, and for interobserver error 0.60-0.83. Gender related differences were minimal. Regardless of gender or radiographic age, the lower canines appear to show the least amount of resorption and the upper first molars the most. The upper and lower second molars have particularly unpredictable life spans. Whilst the lower first molars have a predictable life span that is poor, the life span for the upper first molars is slightly worse.
  
  
  CONCLUSIONS
  Lower canines have a predictable life span that appears to be good, as do upper canines, but of lesser duration than lower canines. Molars have poorer and less predictable life spans.
authors.affiliation: Department of Prosthetic Dentistry, Eastman Dental Institute for Oral Health Care Sciences, UCL (University College), University of London, 256 Gray's Inn Road, London WC1X 8LD, UK.
authors.forename: K
authors.initials: K
authors.lastname: Haselden
authors.forename: J A
authors.initials: JA
authors.lastname: Hobkirk
authors.forename: J R
authors.initials: JR
authors.lastname: Goodman
authors.forename: S P
authors.initials: SP
authors.lastname: Jones
authors.forename: K W
authors.initials: KW
authors.lastname: Hemmings
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000848:Anodontia / Q000000981:diagnostic imaging*; D002648:Child; D003481:Cuspid / Q000002:abnormalities / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging; D008437:Maxilla / Q000000981:diagnostic imaging; D008963:Molar / Q000002:abnormalities / Q000000981:diagnostic imaging*; D015588:Observer Variation; D011379:Prognosis; D011862:Radiography, Panoramic; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012391:Root Resorption / Q000145:classification / Q000000981:diagnostic imaging*; D012737:Sex Factors; D013223:Statistics as Topic; D014094:Tooth, Deciduous / Q000000981:diagnostic imaging*