title: A prediction model for root caries in an elderly population.
abstract: OBJECTIVE
  To identify factors associated with root caries development in a 12- month period, in an elderly Mexican population, so as to develop a prediction model for the occurrence of root caries.
  
  
  METHODS
  A case-cohort study was carried out with 698 randomly selected beneficiaries of the Mexican Institute of Social Security (IMSS), residing in the southeast of Mexico City. Initially, base line (t₀) data regarding sociodemographic variables, general health, general and oral healthy habits, salivary conditions, cariogenic microorganisms and oral health clinical indicators were collected. Twelve months from the date of the first clinical evaluation (t₁), a new examination was carried out to determine the root caries increment. Variables that showed a significant association (P ≤ 0.05) with the root caries increment were included in the prediction model.
  
  
  RESULTS
  Six hundred and ninety-eight elderly subjects were included in the cohort (t₀), with 76.1% (n = 531) of the elderly patients followed up at 12 months (t₁). Incidence of root caries was 21.7% (n = 115), a mean root caries increase of 0.4 (1.0) surfaces. The variables, DLBA limitations (Yes), smoking (Yes), mouthwash (No), Mutans streptococci (≥10⁵ CFU/ml), healthy root surfaces (≥6) and Root Caries Index (≥8%), showed a statistically significant association (P < 0.05). This model showed a correct classification in 80.0% (n = 425) and an area under the Receiver Operating Characteristic curve of 0.75.
  
  
  CONCLUSIONS
  This is a good prediction model for the 12 months root caries increment in this population of elderly Mexicans.
authors.affiliation: Unidad de Investigación Epidemiológica y en Servicios de Salud, Área de Envejecimiento, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social, México, D.F., México.
authors.forename: Sergio
authors.initials: S
authors.lastname: Sánchez-García
authors.forename: Hortensia
authors.initials: H
authors.lastname: Reyes-Morales
authors.forename: Teresa
authors.initials: T
authors.lastname: Juárez-Cedillo
authors.forename: Claudia
authors.initials: C
authors.lastname: Espinel-Bermúdez
authors.forename: Fortino
authors.initials: F
authors.lastname: Solórzano-Santos
authors.forename: Carmen
authors.initials: C
authors.lastname: García-Peña
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D005260:Female; D006305:Health Status Indicators; D006801:Humans; D015994:Incidence; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D009909:Oral Health; D011237:Predictive Value of Tests; D012372:ROC Curve; D012307:Risk Factors; D017213:Root Caries / Q000453:epidemiology*; D011795:Surveys and Questionnaires; D014505:Urban Population