Lateral window sinus augmentation was performed on each side during appointments spaced 3 months apart, following the technique developed by Tatum in 1974. For each site, a midcrestal mucoperiosteal incision with buccal releases was created, and the lateral Schneiderian membrane of the maxillary sinus exposed through an ovoid window osteotomy of about 15 mm diameter. Osteotomy was performed using a piezotome (Piezotome 2, Acteon North America, and Mount Laurel, NJ, USA). Thereafter, the Schneiderian membrane was reflected away from the inferior floor of the sinus cavity with a mushroom-shaped Piezotome insert (Sinus surgery kit, Acteon North America, Mount Laurel, NJ, USA) and Sinus curettes (Sinus surgery curette kit, ACE Surgical Supply, Brockton, MA, USA) until the inferior most 15 mm of the medial wall was felt and seen. During both surgeries, we noticed small tears of 5 mm in the mid-portion of the mobilized Schneiderian membranes and repaired those by placing a double layer of 2 cm × 2 cm × 1.5 mm thick collagen tape (RCT, cut to shape, ACE Surgical Supply, Brockton, MA, USA) over the tears, which stabilized the membrane. We then placed a 1:1:1 mixture of cancellous and cortical allograft (AlloOss, ACE Surgical Supply, Brockton, MA, USA) and bovine xenograft (NuOss, ACE Surgical Supply, Brockton, MA, USA) into the space created between the former floor of the sinus cavity and collagen tape-covered Schneiderian membrane. Buccal access windows were then covered with a resorbable collagen membrane (resorbable collagen, ConFORM, ACE Surgical, Brockton, MA, USA) as suggested by Wallace and Froum [16], and the surgical site closed with continuous sutures (PTFE 3-0, Cytoplast, Osteogenics, Lubbock, TX, USA). No complications were reported by the patient and only when questioned he reported a short-lived episode of postnasal drip with few embedded “sand grains” after the surgery on the left side. We waited then for 10–12 months prior to further evaluation to allow complete dissolution of allograft [17] and allow complete bone formation [18].