First concept ((": platelet rich fibrin "[Mesh]) OR "Maxillary sinus floor augmentation "[Mesh]) OR "Dental Implants"[Mesh]
Second concept (("Platelet Rich Fibrin "[Mesh]) OR " Maxillary Sinus Floor Augmentation" [Mesh]) OR "Dental Implants"[Mesh] OR "Bone Graft" (TW)
Third concept (("Platelet-Rich Fibrin "[Mesh]) And "Sinus Floor Augmentation"[Mesh]) And "Dental Implants"[Mesh] And" Bone Graft" [Mesh] (TW)
Fourth concept (("Platelet-Rich Fibrin "[Mesh]) And ("Maxillary Sinus Floor Augmentation "[Mesh])

TW = text word.