94th European Orthodontic Society Congree, Edinburgh, United Kingdom, 17 - 21 June 2017, pp.95
AIMS: To follow-up long-term the enamel colour changes observed in the gingival, middle, and incisal thirds of the buccal tooth surfaces due to fixed orthodontic treatment.
MATERIALS AND METHOD: One hundred and twenty maxillary central, lateral and canine teeth of 20 subjects who had fixed orthodontic treatment. Spektro Shade was used to evaluate the colour changes of teeth. Measurements were made from the gingival, middle, and incisal thirds of the buccal surfaces of the teeth after
fixed orthodontic treatment (AT) and at 3 (T1), 6 (T2) and 12 (T3) month of the retention phase. The CIE L*a*b* system that expresses the colour coordinates in L*, a* ve b* symbols was used to determine tooth colour and ΔE values between the different time periods were calculated. Repeated measurement analysis of variance was used in evaluating the colour changes.
RESULTS: Enamel colour changes observed in the gingival, middle and incisal thirds of the maxillary central, lateral and canine teeth at AT-T1, AT-T2, AT-T3, T1-T2, T1-T3 and T2-T3 year were statistically significant within themselves. The ΔE values of gingival, middle and incisal thirds were between 1.67-3.62, 1.52-3.57, and 1.31- 3.55, respectively and it was determined that visible but clinically acceptable colour changes occurred. CONCLUSION: While the most enamel colour change was observed at T3, the least enamel colour change was observed at T2. The enamel colour change observed in the gingival third was more than in the middle and incisal thirds.