Multifactorial modeling for root caries prediction

The study was part of a series of investigations aiming at the development of diagnostic caries tests for screening of risk subjects. The material consisted of 100 adult subjects (mean 62 yr, range 47-79 yr), 50 of these under chronic medication. The series of tests included two chairside registrations, i.e. incipient demineralization of exposed root surfaces without cavitation (RD 1) and quantitation of visible plaque (VPT%), three microbiological tests for mutans streptococci, lactobacilli, and candida/yeasts and three tests on stimulated saliva, i.e. secretion rate, buffering capacity and sucrase activity. A thorough clinical examination was conducted at the baseline and 1-yr registration phases, caries being registered at a tooth surface level according to WHO recommendations separately for coronal and root caries. Considerably more root caries than coronal caries developed during the observation period. For coronal caries increment, the predictive value of any of the tests was not significant. For root caries, however, the association between several tests and prospective caries increment was significant. Subsequent multifactorial modeling yielded the highest predictive value to the combination of Past Root Caries Experience (OR 25.0, Visible Plaque (OR 4.2), Candida (OR 8.0) and Lactobacilli (OR 5.8). A positive finding of Past Root Caries (RDFS) or the combination of the other three tests (Can, LB, VPT%) as criteria for selection in screening for root caries produced good accuracy (84.0) and a relative risk of 5.5.