The implants were successfully placed with primer stability. LATERAL SCREW TECHNIQUE: T-PRF AS A SOLE GRAFT MATERIAL FOR MAXILLARY SINUS AUGMENTATION WITHOUT IMPLANT PLACEMENT: A CASE SERIES Ercan E a, Tunalı Mb, Özdemir H c, Kasnak G d, Koyuncuoğlu Ce, Kayıpmaz Sa, Fıratlı Ed a Karadeniz Technical University, Trabzon, Turkey , b Bezmi Alem Vakıf University, İstanbul, Turkey c Osmangazi University, Eskişehir, Turkey, d İstanbul University, İstanbul, Turkey, e Aydın University, İstanbul, Turkey OBJECTIVE: The sinus augmentation procedure is a predictable approach for augmentation of the atrophic posterior maxilla. Autogenous grafts are the gold standard for sinus augmentation. Despite their osteogenic capacity, increased morbidity and limited availability make them less desirable. Titanium prepared PRF (T-PRF) was shown to induce bone regeneration. The post-operative sixth month results of three cases for sinus augmentation procedures with T-PRF and mini-screws were presented. METHODS: Three systemic healthy female patients were referred for dental implant placement. First, Phase I therapy and oral hygiene motivation was performed. Surgical Phase: Full-thickness flap was elevated after local anesthesia and a rectangular window was shaped on the buccal side of maxilla. The bone of the lateral window (if it was still attached to the membrane) was moved from its lower edge to the inside and upwards. After the membrane was sufficiently exposed, the mini-screws of varying sizes were placed horizontally, above the lateral window, from outside to the inside to hold the membrane for reducing the ongoing pressure of membrane during healing period. T-PRF Preperation: The patient’s own blood was drawn into a 20-ml injector and separated immediately into two Grade IV sterile titanium tubes. The tubes were centrifuged at 2,700 rpm for 12. The T-PRF clot that was formed was removed from the tube. The T-PRF clot was cautiously cleaved from the underlying layer containing red blood cells and was placed between two sterile gauze pads such that the buffy coat components could be placed on the mesial and distal aspects, and sufficient compression was applied to separate the T-PRF from the serum to obtain the membrane. The condensed T-PRF membranes were placed into the sinus cavity to completely fill the cavity (Fig 1a 2a). The remaining one T-PRF membrane was placed over the window Flap was placed and sutured with 4-0 resorbable sutur (Pegalak® ,Turkey). Antibiotic and analgesic were prescribed and the patient recalled after 10 days. Radiographic Analysis: The patients were evaluated by Cone Beam Computed Tomography (CBCT) at baseline and post-op 6 months (Fig 1b-1e, 2b, 2c, 3a, 3b). (Left Side) (Right Side) CASE 1. Fig. 1a. T-PRF & Lateral Screw Technique 5 piece (Graft) 1 piece (Membrane) Fig. 1d. Pre-op Fig. 1b. Pre-op Fig. 1c. Post-op 6 m. Fig. 1e. Post-op 6. m CASE 2. CASE 3. Fig 3a. Pre-op Fig 3b.Post-op 6.m 5 piece (Graft) 1 piece (Membrane) Fig. 2a. Lateral Screw Technique Fig. 2b. Pre-op Fig. 2c. Post-op 6. m RESULTS: The post-operative healings were uneventful and morbidities were minimal. The average vertical bone gain was 2.66 (0.5-6.0) mm. The average bone volume increment was 0.93 (0.505-1.245) cm3 according to CBCT analysis (baseline and post-op 6 months). The implants were successfully placed with primer stability. Non-autogenous bone graft materials may actually delay, rather than accelerate bone formation, because of foreign body reaction and formation of fibrous encapsulation. The preferance of completely autogeous materials is critical for enhancement of the quality of wound healing. It seems that T-PRF may be a predictable autogenous material to alternative for autogenous bone graft. CONCLUSION: