M Beerens

EFFECTS OF MI PASTE PLUS ® : A 12-MONTHS FOLLOW-UP 5 97 (Bailey et al. , 2009). When evaluating in vivo studies, Chen (Chen et al. , 2013) reported a lack of reliable evidence to support remineralising agents for the treatment of post-orthodontic WSL. A systematic review described by Li (Li et al. , 2014), reported the same conclusion, although, in this systematic research, the effect of CPP-ACPF was assessed for orthodontic and non-orthodontic lesions. Our findings contradict the findings of Bailey (Bailey et al. , 2009) and Bröchner (Bröchner et al. , 2011) who reported a positive effect of casein supplements after only 12 and 4 weeks, respectively. Bailey concluded a positive effect within 12 weeks although no statistical differences were found using ICDAS code 2. Their conclusion was based on visual assessment of lesion activity or inactivity. Bröchner reported a reduction in lesion area of 58 % after 4 weeks. However, the lesions investigated were very small (0.19 mm 2 ). One may debate clinical relevancy. Andersson (Andersson et al. , 2007) compared the effects of CPP-ACP with fluoride mouthwashes on the regression of WSL and concluded that both regimens could promote regression of WSL after debonding of fixed orthodontic appliances, though the visual evaluation suggested an aesthetically more favourable outcome of the CPP-ACP. Strength and limitations of this study The study was performed in a general population of teenagers in Amsterdam, The Netherlands. The Netherlands is part of Western Europe and has no water fluoridation. Therefore, water fluoridation did not affect the outcome of this study. WSL developed during orthodontic treatment appear more rapidly and are more porous than WSL in non-orthodontic patients. As a result, the findings of this study are only applicable to WSL developed during orthodontic treatment. The efficacy of this remineralisation agent on WSL after orthodontic treatment with full fixed appliances was not influenced by background levels of fluoride. As for all randomized clinical trials, non-compliance of the subject could have influenced the result. The assessment of product use via returned product failed because none of the subjects returned their product tubes at recall visits. Also, we did not use an application tray, for example, a removable clear retainer to improve the cream to stay in place. Though by not using an application tray, saliva could now also influence possible remineralisation. One of the possible limitations influencing the results of the study is the preservation of CPP-ACPF in MI Paste Plus ® . This could be the explanation for