M Beerens

28 CHAPTER 2 cheek retractors were used for lateral pictures (Pelz & Partner, Lindenberg im Allgäu, Germany. Set: medium & large double end, for lateral area 720-0007). Pictures were taken by trained orthodontic residents. Clinical plaque removal was performed prior to photography. For each subject and time point pictures were collected and combined in a photography gallery comprising four pictures per patient (Figure 1) and printed on high quality photographic paper. Each photograph gallery was assigned a random number by M.H.V., according to a computer-randomization scheme, to ensure examiners (F.B. and M.W.B) were blinded for subject and time point of recording. Photography galleries were analysed by two calibrated examiners (F.B.) and (M.W.B). Photographs were analysed in random order for subject and time using the ICDAS-II criteria (Health., 2001), where code 1, First Visual Change in Enamel, seen only after prolonged air drying, was not used, given that no air drying was applied before photographs were made. Also, at T1 ICDAS codes 5 and 6 were not given due to exclusion criteria (Table 1). TABLE 1. Code description for ICDAS, Visual transition (VT) and QLF. CODE Description ICDAS 0 Sound 1 First Visual Change in Enamel (excluded in this research) 2 Distinct Visual Change in Enamel 3 Localized Enamel Breakdown (without clinical visual signs of dentinal) involvement 4 Underlying Dark Shadow from Dentin 5 Distinct Cavity with Visible Dentine (excluded in this research) 6 Extensive Distinct Cavity with Visible Dentine (excluded in this research) RESTORATION Restoration Applied VISUAL TRANSITION 0 Sound 2 Distinct Visual Change in Enamel 3 Localized Enamel Breakdown (without clinical visual signs of dentinal) involvement IMPROVED Lesion Improved at T2 RESTORATION Restoration Applied at T2 SAME Lesion Same at T1 and T2 WORSE Lesion Worsened at T2 QLF IFL (%.mm 2 ) 0 Integrated fluorescence loss =0, i.e. sound 1 Integrated fluorescence loss > 0 to ≤ 5 2 Integrated fluorescence loss >5 to ≤25 3 Integrated fluorescence loss >25