title: Tooth loss and osteoporosis: the OSTEODENT Study.
abstract: OBJECTIVE
  To determine the cross-sectional association of the osteoporotic status of patients with the number of their teeth, with and without taking into account age and/or smoking.
  
  
  METHODS
  At four centres, the study recruited 665 females aged 45-70 years and the number of teeth was counted for 651 subjects. Bone density was measured at the total hip, femoral neck and lumbar spine.
  
  
  RESULTS
  The mean number of teeth in the osteoporotic subjects was 3.3 fewer than normal subjects and 2.1 fewer if those with no teeth were excluded. The association between osteoporosis and having <6 or having <28 teeth remained significant after adjusting for age, smoking and centre with p-values of 0.016 and 0.011, respectively. A single regression model for tooth count with normal errors would not fit all the data. By fitting mixture regression models to subjects with tooth count >0, three clusters were identified corresponding to different degrees of tooth loss. The overall effect of osteoporosis was as follows: -1.8 teeth before and after adjusting for smoking, -1.2 teeth after adjusting for age, and -1.1 teeth after adjusting for both age and smoking.
  
  
  CONCLUSIONS
  We have established a significant association between osteoporosis and tooth loss after adjusting the effect for age and smoking.
authors.affiliation: Dental School, University of Athens, Athens, Greece.
authors.forename: Kety
authors.initials: K
authors.lastname: Nicopoulou-Karayianni
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Tzoutzoukos
authors.forename: Anastasia
authors.initials: A
authors.lastname: Mitsea
authors.forename: Athanasios
authors.initials: A
authors.lastname: Karayiannis
authors.forename: Kostas
authors.initials: K
authors.lastname: Tsiklakis
authors.forename: Reinhilde
authors.initials: R
authors.lastname: Jacobs
authors.forename: Christina
authors.initials: C
authors.lastname: Lindh
authors.forename: Paul
authors.initials: P
authors.lastname: van der Stelt
authors.forename: Philip
authors.initials: P
authors.lastname: Allen
authors.forename: Jim
authors.initials: J
authors.lastname: Graham
authors.forename: Keith
authors.initials: K
authors.lastname: Horner
authors.forename: Hugh
authors.initials: H
authors.lastname: Devlin
authors.forename: Susan
authors.initials: S
authors.lastname: Pavitt
authors.forename: Jingsong
authors.initials: J
authors.lastname: Yuan
mesh_terms: D015502:Absorptiometry, Photon; D017677:Age Distribution; D000368:Aged; D015519:Bone Density; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging; D006801:Humans; D007568:Jaw / Q000000981:diagnostic imaging; D008875:Middle Aged; D010024:Osteoporosis / Q000150:complications*; D011862:Radiography, Panoramic; D012907:Smoking; D016388:Tooth Loss / Q000150:complications*