Seven hundred and ninety-six adult subjects (mean age 39.9 years) received visual-tactile examinations for root caries over a three-year period. All subjects were employed or the spouses of employees and resided in fluoride-deficient communities on Long Island, New York. Incremental caries data were analyzed to provide descriptive information about the susceptibility of individual teeth and surfaces to root caries. Molars were most prone to root caries/fillings, followed in decreasing order by premolars, canines and incisors. While canines and incisors had a nearly identical increment, since there are half as many canines as incisors in a mouth, canines are actually twice as susceptible to root caries/fillings. Facial surfaces comprised 53 percent of the increment followed by distal, lingual and mesial surfaces. Approximately 70 percent of the DFS for facial and lingual surfaces were fillings, compared to approximately 50 percent for mesial and distal surfaces, suggesting that part of the increment for facial-lingual surfaces may be treated abrasion areas rather than caries.