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

The treatment of anterior open bite (AOB) through maxillary molar intrusion using zygomatic buttress temporary anchorage devices (TADs) is quite nuanced and dependent on various factors, such as the degree of open bite, skeletal patterns, and the overall treatment plan.

Maxillary molar intrusion can significantly contribute to the vertical component of the AOB treatment because it helps to reduce the vertical height between the molars and incisors. The ability to intrude the maxillary molars effectively through TADs anchored in the zygomatic buttress allows for controlled movement that can achieve substantial results.

Research and clinical experience typically indicate that achieving an intrusion within the range of 5-6 mm effectively addresses open bite issues in many cases. This range strikes a balance between exerting enough force to influence the desired dental and skeletal changes, while also maintaining periodontal health and stability. Furthermore, this level of intrusion can facilitate the alignment of the dental arch and contribute to improving occlusion, thereby addressing the AOB effectively.

The other ranges of intrusion—such as 3-4 mm or higher than 6 mm—might not consistently yield the same degree of efficacy across various cases, hence why 5-6 mm is often regarded