M Beerens

DGGE FOR CARIES RISK ASSESSMENT IN ORTHODONTICS 3 51 Caries risk assessment is currently based on past caries experience or DMFS scores complemented with current oral hygiene level (Sundell et al. , 2013). Additionally, a dip slide test may be used to assess levels of S. mutans and Lactobacilli spp (Krasse, 1988; Anderson et al. , 1993). In orthodontic patients these risk indicators have low value (Boersma et al. , 2005; van der Kaaij et al. , 2015). Traditional DMFS scores do not provide information about incipient lesions. Even individuals without symptoms of caries prior to orthodontic treatment are at risk of developing WSL during fixed appliance treatment (van der Kaaij et al. , 2015). Furthermore, during fixed appliance treatment, nearly all patients are ‘millionaires’ in terms of Streptococcal counts, annihilating the discriminatory value of dip slide tests (Boersma et al. , 2005). In this study a secondary aim was to test if traditional plate counting may overcome this issue. Similar to DGGE outcome, no differences were observed between the relative amounts of aciduric flora, S. mutans , Lactobacillus spp . and C. albicans of orthodontic patients undergoing fixed appliance treatment with or without WSL. In this study only a limited number of orthodontic patients with and without WSL on the bracketed surfaces were included. The numbers of subjects with WSL (28) and without WSL (9) were unbalanced. These numbers do reflect the high percentage of subjects with WSL during orthodontic treatment at the ACTA clinic at the time of the study. In the WSL group the ranges for DMFS, bleeding percentage and their treatment duration extended towards higher values in comparison to the group without WSL. Bleeding percentage was discriminatory between subjects with or without WSL developed on the previously bracketed surfaces. The outcome measures of this study, DGGE band numbers and CFU counts, were not discriminatory, in assessing the presence or absence of WSL. The outcome of the study shows such a small difference between groups with or without WSL that the use of DGGE as screening test for caries risk in orthodontic patients seems unfeasible. Although the numbers of bands detected were inconclusive, each subject showed a specific individual banding pattern. Monitoring individual changes in banding pattern and plaque diversity in time during orthodontic treatment may thus still be worthwhile to investigate as means to assess an increase in caries risk in orthodontic patients.