title: A prospective study of mandibular trabecular bone to predict fracture incidence in women: a low-cost screening tool in the dental clinic.
abstract: Bone structure is the key to the understanding of fracture risk. The hypothesis tested in this prospective study is that dense mandibular trabeculation predicts low fracture risk, whereas sparse trabeculation is predictive of high fracture risk. Out of 731 women from the Prospective Population Study of Women in Gothenburg with dental examinations at baseline 1968, 222 had their first fracture in the follow-up period until 2006. Mandibular trabeculation was defined as dense, mixed dense plus sparse, and sparse based on panoramic radiographs from 1968 and/or 1980. Time to fracture was ascertained and used as the dependent variable in three Cox proportional hazards regression analyses. The first analysis covered 12 years of follow-up with self-reported endpoints; the second covered 26 years of follow-up with hospital verified endpoints; and the third combined the two follow-up periods, totaling 38 years. Mandibular trabeculation was the main independent variable predicting incident fractures, with age, physical activity, alcohol consumption and body mass index as covariates. The Kaplan-Meier curve indicated a graded association between trabecular density and fracture risk. During the whole period covered, the hazard ratio of future fracture for sparse trabeculation compared to mixed trabeculation was 2.9 (95% CI: 2.2-3.8, p<0.0001), and for dense versus mixed trabeculation was 0.21 (95% CI: 0.1-0.4, p<0.0001). The trabecular pattern was a highly significant predictor of future fracture risk. Our findings imply that dentists, using ordinary dental radiographs, can identify women at high risk for future fractures at 38-54 years of age, often long before the first fracture occurs.
authors.affiliation: Research & Development Unit in Southern Alvsborg County, Sven Eriksonplatsen 4, SE-503 38 Borås, Sweden. grethe.jonasson@vgregion.se
authors.forename: Grethe
authors.initials: G
authors.lastname: Jonasson
authors.forename: Valter
authors.initials: V
authors.lastname: Sundh
authors.forename: Margareta
authors.initials: M
authors.lastname: Ahlqwist
authors.forename: Magnus
authors.initials: M
authors.lastname: Hakeberg
authors.forename: Cecilia
authors.initials: C
authors.lastname: Björkelund
authors.forename: Lauren
authors.initials: L
authors.lastname: Lissner
mesh_terms: D000328:Adult; D003720:Densitometry; D003740:Dental Clinics / Q000191:economics*; D005260:Female; D050723:Fractures, Bone / Q000175:diagnosis / Q000191:economics* / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008334:Mandible / Q000000981:diagnostic imaging / Q000473:pathology*; D008403:Mass Screening; D008875:Middle Aged; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011859:Radiography; D015203:Reproducibility of Results; D013548:Sweden / Q000453:epidemiology