The prosthodontic rehabilitation of patients with atrophic maxilla is a challenge for a clinician due to the severe compromise of masticatory function and speech with a significant quality of life impact. The poor bone volume found on these patients makes it difficult for conventional rehabilitation with fixed prosthesis and to insert dental implants.

Different surgical techniques with varying degrees of success rate have been described in the literature to deal with cases of maxillary atrophy. Techniques such as major reconstructions using bone graft from the iliac crest associated or not with Le Fort I osteotomy are the most common ones used for these cases. However, these techniques have important biological cost requiring long periods of treatment and are more sensitive to technical errors. The morbidity of these techniques includes the possibility of sinusitis, neurosensory disorders, contamination or exposure of the graft, postoperative pain, mobility difficulties, and insufficient remanent bone after the healing period.

The emergence of the zygomatic implants from Brånemark’s studies gave the surgeons the possibility to obtain a firm anchorage of implants to the zygomatic bone, making the rehabilitation of an atrophic maxilla possible with two or four implants in the anterior maxilla. The high success rate shown by the first protocol suggested by Brånemark triggered a series of studies and the publication of different modifications of the guidelines for zygomatic implants.

The original protocol performed by Brånemark involved the opening of a window at the upper side of the anterior wall of the maxillary sinus to guide the perforations. The implant is placed in an intrasinus position without elevation of the sinus membrane. This step was later modified with an elevation of the membrane to provide the retraction of the sinus mucosa that is preserved in this technique. The zygomatic implants are anchored in the upper second premolar position, passing through the maxillary sinus and making new grounding in the body of the zygoma. In this situation, the emergence of the implants mostly is located palatal to the alveolar crest (Fig. 1a). Trying to simplify this technique, Stella and Warner proposed the preparation of a groove orientation on the zygomatic buttress region, extending from the base of the zygoma, approximately 5 mm of the alveolar bone crest. With this technique (sinus slot technique), the detachment of the sinus membrane is not necessary and part of the zygomatic implant is directly in the maxillary sinus. However, the implant ends up emerging on the alveolar crest level of the first molar in a more vertical angulation, which favors the interface with the prosthesis and also simplifies the placement of the implants (Fig. 1b). Another technique of zygomatic implants is the extrasinus, where the implant is completely out of the maxillary sinus (Fig. 1c).

A number of papers have reported cases of maxillary sinusitis following the placement of zygomatic implants. In a systematic review of retrospective and prospective studies, Chrcanovic and Abreu (2013) found that the most common complication was maxillary sinusitis, affecting 70 cases of the 2402 zygomatic implants installed.

Many studies were conducted to evaluate the success rate of zygomatic implants for the Brånemark’s technique. But Stella and Warner’s technique still needs investigation. In this sense, the present study aimed to evaluate the success of zygomatic implants placed using this technique, investigating the survival rate of the implants, and assess the possible association between sinus disease and the placement of zygomatic implants using this technique and the satisfaction of patients rehabilitated with full fixed prostheses with zygomatic implants.