Oral rehabilitation of the atrophic maxilla is a common clinical challenge, especially in edentulous patients, due to significant bone loss that compromises implant stability and smile esthetics. The All-on-Four protocol has emerged as an effective, minimally invasive, and predictable alternative, eliminating the need for bone grafting procedures while promoting satisfactory functional and aesthetic outcomes. This case report presents a clinical scenario of the rehabilitation of an atrophic maxilla using the All-on-Four technique. The patient, a 70-year-old female who was fully edentulous in the maxilla, reported aesthetic and functional dissatisfaction with her current prosthesis. After clinical and tomographic evaluation, the All-on-Four protocol was indicated for the placement of four Morse taper implants. Two anterior straight implants and two posterior implants angled at 45° were placed to maximize bone utilization and avoid the maxillary sinus. The surgical procedure was performed under local anesthesia, followed by relining of the provisional prosthesis. No adverse event or complications were observed on the day of the surgical procedure or in the postoperative period. After the osseointegration period, intermediate abutments were placed, and the definitive prosthesis was installed. After 6 months, the patient reported complete satisfaction with the treatment, which enhanced both the esthetic and masticatory functions. The case report demonstrates the benefits of the technique, including reduced treatment time, good primary stability, absence of significant morbidity, and excellent functional and esthetic outcomes for the patient. The All-on-Four protocol proved to be an effective and safe rehabilitative solution for cases of atrophic maxilla, contributing to improvements in the patient’s quality of life.