The recommended interval for loading implants in the maxilla is 6 months due to the generally lower bone density (Type III or IV bone) in this region compared to the mandible. The maxillary bone requires a longer healing period to achieve sufficient osseointegration and primary stability. Early loading (6-month healing period ensures optimal implant stability and long-term success in the maxilla.

Reference: Contemporary Implant Dentistry, Carl E. Misch, 3rd Edition.