M Beerens

64 CHAPTER 4 RESULTS Descriptive results From a total of 184 screened participants, 65 were recruited into the study. They were randomly assigned into two groups, of CPP-ACPF product (group A; n = 35) and control (group B; n = 30). A total of ten participants dropped out between T0 and T3, seven from the CPP-ACPF group and three from the control group. The reason given for withdrawal was the time-consuming nature of the study. One further participant from the CPP-ACPF group was found to be WSL free and was removed from the study. The participants did not differ with respect to number of lesions, gender ratio, age, and fixed appliance duration compared with subjects who completed the study. The subject flow in the study is given in Fig. 1. Fifty-four participants (23 male and 31 female; mean age ± SD, 15.5 ± 1.6 years) completed this study. The gender ratio, participant age, and duration of treatment with the fixed appliance before investigation were not statistically significantlydifferentbetweenthegroups. Atotal of 424caries-affectedsurfaces in a total of 1,002 elements were followed throughout this investigation (Table 1). The affected elements were distributed as follows: 14.2% central incisors; 22.6% lateral incisors; 28.3% cusps, and 34.9% premolars. The distributions were equal for the two groups. Questions regarding frequency of brushing and product use were used to get an impression of compliance. Overall compliance in the study was considered moderate. The subjects generally brushed twice a day and used the product at night-time after brushing during the first 6 weeks of the study. Between weeks 6 and 12, the subjects forgot to brush and to use the product on average once a week, and this always occurred at night-time. The assessment of product use via returned product failed entirely because none of the subjects returned their product tubes at recall visits.