Preliminary Approach for Open Lateral Window Technique for Successful Maxillary Sinus Augmentation in the Unrepairable Wide Perforation Area of Schneiderian Membrane

During maxillary sinus augmentation (MSA), bone graft particles displaced through the perforated site can block the ostium and become a risk factor for maxillary sinusitis. The purpose of this case report is to introduce a novel approach for successful lateral MSA performed in the unrepairable perforation area of Schneiderian membrane. In a total of three patients, including two who were unintentionally treated with a split-mouth design, the Schneiderian membrane was irreparably perforated during the sinus floor elevation. After bone grafting was performed on only the sinus floor, the open lateral window technique was performed in which the upper part of the lateral window was opened. After the procedure, unexpectedly, the patient showed transient nasal bleeding, but no unusual clinical events. Most of the bone graft substitutes were not displaced and the exposed portion was covered with a soft tissue. In the sinus graft, clotting of blood, supplied from the perforated Schneiderian membrane and the buccal flap through the open lateral window, appeared to prevent graft displacement. Within the limitations of present case reports, these patients showed that MSA via the open lateral window technique was possible even with a widely perforated Schneiderian membrane that could not be repaired.