The integration of digital planning in orthodontics has revolutionized the accuracy and efficiency of mini-implant placement and is particularly important for Maxillary Skeletal Expansion with bone anchored devices (MARPE). This lecture explores the Bone-First Principle, an approach that prioritizes individualized bone anatomy in determining optimal mini-implant positioning. By using advanced imaging techniques, 3D treatment planning, and guided insertion protocols, clinicians can enhance the success rates of MARPE while minimizing risks of implant failure and complications.