Abstract
Objective: Determine whether coronal caries experience to the 30s predicts root surface caries experience by age 38.
Method: Prospective study of a complete birth cohort (N = 1037) born in 1972/73 in Dunedin, NZ. Dental examinations were conducted at ages 5, 9, 15, 18, 26, 32 and 38. Root surface caries data were first collected at age 38. Data from ages 5 through 32 were used previously to identify low, medium and high life-course trajectories of caries experience and plaque accumulation.
Results: Of the 916 dentate individuals examined at age 38, 23.0% had 1+ root DFS, 17.2% had 1+ root DS and 11.4% had 1+ root FS. The mean root DS, FS and DFS were 0.6 (sd, 3.5), 0.3 (1.1) and 0.9 (3.8), respectively. The mean Root Caries Index score was 7.2% (sd, 18.0). Age-38 coronal DMFS and root surface caries DFS were only weakly correlated (r = 0.32), but root surface caries experience was strongly associated with coronal caries trajectory, with the mean RCI in the low, medium and high caries trajectory groups being (respectively) 4.4%, 8.0% and 13.5% (P <0.0001); their prevalence of 1+ root DFS was 14.5%, 25.9% and 42.2% (P<0.0001). Those in the high coronal caries trajectory were more likely to have 1+ root surface DFS (Odds Ratio = 3.83; 95% CI 2.33, 6.30); for the medium trajectory, the OR was 1.86 (1.25, 2.75).
Conclusion: Lifelong coronal caries experience (represented by discrete longitudintal trajectories of caries experience) is indeed a risk factor for root surface caries experience by age 38.