American Board of Orthodontics (ABO) Practice Exam 2026 – All-in-One Resource to Master Your Orthodontics Certification!

The statement that RR greater than 1.5mm is clinically significant is accurate because significant root resorption is typically considered to begin at this threshold. In orthodontics, it is recognized that root resorption may occur during treatment, and its potential impact on dental health necessitates a clear understanding of what constitutes clinically significant resorption. This level is associated with concerns regarding tooth stability after treatment and overall long-term periodontal health.

Understanding root resorption is crucial in orthodontics, as it allows practitioners to monitor and manage the risks involved with movement of teeth. While some degree of root resorption happens in almost all patients undergoing orthodontic treatment, identifying a threshold like 1.5mm helps in determining when intervention might be necessary.

Other statements lack accuracy in their generalizations about root resorption. For example, not all patients experience significant resorption, and incidence varies among individuals. The claim that root resorption is equally prevalent in adults and adolescents overlooks the differences in biological responses and tissue adaptation between age groups. Similarly, while root resorption occurs, stating that its prevalence with orthodontics is low does not reflect the understanding that even minimal levels of resorption can occur in a considerable number of patients. Hence, the significance of RR above the 1.