Root caries susceptibility in periodontally treated patients. Results after 12 years

The aim of the investigation was to study the individual susceptibility to root caries in periodontally treated patients in a long-term follow-up of 12 years. Age, plaque score, salivary counts of lactobacilli and mutans streptococci, salivary secretion rate and buffer effect, oral sugar clearance time and dietary habit index were tested as possible predictors for root caries incidence. During the whole observation period of 12 years, new root caries lesions were recorded in 24 of a total of 27 patients. In 8 of these, the root caries incidence was between 1 and 5, in 7 between 6 and 9 and in 9, 12 or more new DFS. However, the annual mean number of new DFS was rather low. 13 patients with > 5 new DFS% during the 3rd 4-year period (years 9-12) differed significantly from 14 patients with < or = 5 new DFS% in salivary mutans streptococcus counts (p < 0.01), plaque scores (p < 0.001) and new DFS% during the 2nd 4-year period (years 5-8) (p < 0.001). Simultaneously, risk values among the variables tested at the 8-year examination were about 3 x more prevalent in patients that developed > 5 new DFS% in years 9-12 than in those with < or = 5 new DFS%. During the whole 12-year observation period, smokers had significantly more root caries than non-smokers (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)