Interest in a new test for caries risk in adolescents undergoing orthodontic treatment.

It has been reported that patients undergoing orthodontic treatment present a high risk of caries. Recently, an immediate chair-side test was proposed, displaying the intra-oral lactic acid production of cariogenic bacteria. The aim of this 12-month follow-up prospective cohort study was to evaluate the association between having a high score on this test and caries occurrence in 110 young patients scheduled for orthodontic treatment. Caries occurrence was studied by Kaplan-Meier curves and Multivariate Cox models allowed the examination of its association with covariates. Fifty four patients developed at least one carious lesion during the follow-up period. At baseline, approximately 70% of the patients presented a high risk of caries according to the test and this number came close to 80% by the study's completion. According to the Kaplan-Meier estimator, 51% (CI(95%) 0.40, 0.60) of the sample would have developed at least one carious lesion during the follow-up. The test score was then associated with age, DMFT, and caries occurrence. This study showed that a high test score at baseline associated with a high DMFT predicted a high risk of caries (RR = 2.6). Taking the patient's age into consideration, an increase of 1 year resulted in a 10% decrease of the risk of caries occurrence (RR = 0.89). Within the limits of this longitudinal study, it may be concluded that this test is useful to evaluate the risk for dental caries in adolescents with orthodontic treatment. Furthermore, the distribution of the lesions in our sample suggests specific clinical approaches for this group of patients.