Teeth that have been finished using orthodontic appliance has a tendency to return to the starting position. This is called a relapses or a return of tooth position into an early form of malocclusion. Research in Europe showed that the prevalence of relapse is still high. Relapse is caused by many factors. In Indonesia, the research on relapse is still rarely performed. Measurement of relapse can be done using IOTN (Index of Orthodontic Treatment Need). Aim: The aim of this research is to determine the prevalence of relapse after treatment with fixed orthodontic appliance using IOTN. Material and Method: This study used 24 samples that have been finished using bracket and at this time met the inclusion criteria. Assessment using Index of Orthodontic Treatment Need which consists of two components, Aesthetic Component and Dental Health Component. Shapiro-Wilk was tested to asses data normality and homogeneity. Wilcoxon test was used to asses paired data differences on abnormal data distribution Result: The Wilcoxon analysis result on the measurement of AC and DHC show the value of p <0.005, which means there are significant differences of scores after finished using bracket and at this time. Conclusion: There is significant differences between IOTN score value of AC and DHC after finished using bracket and at this time. That’s mean there was prevalence of relapse after treatment using fixed orthodontic appliance