M Beerens

SUMMARY 7 117 SUMMARY (ENG) Chapter 1 General introduction of the thesis This thesis describes the efficacy of a remineralisation agent called MI Paste Plus ® for the remineralisation of early caries decay or so called white spot lesions (WSL) after orthodontic treatment with fixed appliances. Orthodontic fixed appliances often result in the formation and progression of WSL. Limited access of saliva and inadequate oral hygiene procedures allow undisturbed and prolonged contact between plaque and the bracketed tooth surface, which predisposes the respective site to being caries susceptible. While the strategies in the primary prevention of WSL are nowadays evidence based, our knowledge about control and atraumatic care of existing WSL, the secondary prevention, is limited. Treatment of existingWSL that havebeen formedduringorthodontic treatment should prevent hypermineralisation of the surface. This hypermineralised layer inhibits the ion movement to the subsurface and prevents mineralisation in the deeper layer. This results in the maintaining of the whiteness of the lesions. Therefore we have studied a minimal intervention strategy based on CPP-ACPF technology. This agent provides bioavailable calcium and phosphate into saliva and plaque enabling to drive remineralisation within the deeper layer of the WSL. MI Paste Plus ® is a commercially available remineralisation agent, based on this technology, claiming to remineralise WSL. We have used a combination of several independent outcome measures, which could be informative to assess caries risk and severity. In this thesis a single centre prospective double blind randomised placebo controlled trial is described. This trial was conducted at the Department of Orthodontics, Academic Centre of Dentistry Amsterdam, the Netherlands from January 2008 to August 2010. A 12 months evaluation and the use of several independent detection methods strengthens the conclusions drawn.