American Board of Orthodontics (ABO) Practice Exam 2025 - Free Orthodontics Practice Questions and Study Guide

The relapse rate after surgical assisted rapid palatal expansion (SARPE) tends to be higher compared to Lefort procedures for intermolar widths. SARPE is typically performed to expand narrow maxillary arches and involve a segmental osteotomy that allows for expansion of the palate. While it can be quite effective during the initial treatment phase, there is a propensity for relapse post-treatment, often due to the nature of the skeletal and soft tissue adaptations that occur.

In contrast, Lefort procedures involve more extensive surgical modifications to the maxilla as a whole, providing not only a wider intermolar distance but also more comprehensive changes to the skeletal structure. The stability post-surgery tends to be greater as the surrounding soft tissues are more adapted to the new bone positions. Consequently, the risk of significant relapse can be reduced.

The variable nature of patient responses can affect outcomes; however, the overall trend in research suggests that SARPE carries a greater likelihood of intermolar width relapse compared to Lefort osteotomy procedures, making that differentiation critical in treatment planning.