Abstract
INTRODUCTION AND AIMS: Maxillary transverse deficiency (MTD) affects approximately 10% of adults, but conventional expansion treatments are often ineffective and risky in mature patients due to suture fusion. Although microimplant-assisted rapid palatal expansion (MARPE) improves outcomes, it relies on sufficient bone thickness, posing a challenge for individuals with thin palatal bone. This study evaluates a digitally personalized MARPE approach, guided by cone-beam computed tomography-based bone mapping, for adults with MTD and thin bone (<2.5 mm). METHODS: A retrospective analysis was conducted on 18 patients. Custom MARPE appliances were designed using computer-aided design/computer-aided manufacturing technology, with microimplants placed strategically using surgical guides. Skeletal, dental, and zygomatic changes were assessed via pre- and postexpansion cone-beam computed tomography and cephalograms. RESULTS: All patients were successfully treated without implant failure. Significant skeletal expansion was achieved: anterior nasal spine width increased by 5.19 mm, posterior nasal spine by 4.49 mm, and maxillary basal width by 4.05 mm (all P < .01). Dental side effects were minimal. Significant three-dimensional remodelling of the zygomaticomaxillary complex was observed, along with sagittal improvements in SNA and ANB angles (0.57° and 1.54°, respectively) and increased anterior facial height (2.00 mm, P < .01). All measurements showed high reliability (intraclass correlation coefficient >0.90). CONCLUSION: Personalized MARPE demonstrated promising results for MTD in patients with thin palatal bone, providing significant skeletal expansion with minimal adverse dental effects. CLINICAL RELEVANCE: This study provides evidence that a digitally personalized MARPE protocol, guided by CBCT, is a feasible and well-tolerated treatment approach for adults with maxillary transverse deficiency and critically thin palatal bone. It provides significant skeletal expansion with minimal dental side effects, offering a viable solution for a patient population that has limited and high-risk treatment options.