In this case study, we investigated the feasibility of using an immediate loading scheme after bilateral lateral maxillary sinus openings and delayed implant placement in a patient with a severely atrophied edentulous maxilla (edentulous). The results. The patient, a 63-year-old male, presented with the complaint “request for implant fixed restoration of maxillary edentulism”. History: In the past 15 years, maxillary teeth were extracted one after another due to periodontitis, and he wore a maxillary monomandibular complete denture for many years, with no history of systemic diseases, no history of smoking, no history of parafunctional occlusion such as night grinding. The facial appearance was basically symmetrical, with good mouth opening, lack of maxillofacial fullness, shortened lower 1/3 of the face, collapsed upper lip, poor upper lip fullness, less lip red exposure, and low smile line. Missing maxillary teeth, heavy alveolar bone resorption, missing mandibular left mesial incisor, missing mandibular bilateral second molars. The maxillary and mandibular Class III relationship, preoperative CBCT showed that the maxillary anterior region could be severely deficient in bone, with only 3.5 mm in height and 3 mm in width remaining, and the posterior region was deficient in available bone, with 1-2 mm remaining on the left side and 3-4 mm on the right side (Figures 1~3). (1) Bilateral maxillary sinus lateral wall openings for bone grafting to increase vertical bone volume, and re-lining the original denture with soft lining material 1 week after surgery; (2) 6 months post-operative review, the row of teeth to produce a diagnostic wax pattern, and after the patient was satisfied with the trial wear, the radiographic positioning guide was made, CBCT was taken to determine the implantation site, and the positioning guide was applied to place the implants in the bilateral upper posterior region; (3) fabrication of temporary restorations and immediate loading; ( (4) CAD-CAM fabrication of permanent restorations: pure titanium cutting brackets and all-ceramic single crowns. After the restoration, the patient had no loosening of the implant, no redness or swelling of the gingiva and no pressure, and the implant restoration had good masticatory function and aesthetics. Radiographic examination showed that the patient’s maxillary sinus bone gain was well maintained, the implant was well integrated with the surrounding bone, there were no dark shadows around the implant, and the abutment and the margin of the restoration were tightly fitted. The patient’s temporary fixed restoration made by PICK-UP technique and the pure titanium cutting bracket and single crown restoration made by CAD/CAM technique can be successfully applied to this patient with severe maxillary atrophy without teeth (dentition).