This issue of Dental Clinics of North America focuses on Unanswered Questions in Implant Dentistry and is edited by Dr. Mohanad Al-Sabbagh. Articles will include: Is there a contraindication for dental implant?; Should cone beam tomography be routinely obtained in implant dentistry?; What is the optimal ridge preservation technique?; Resorbable versus non-resorbable membrane: when and why?; Is there an alternative to an invasive site development?; Tissue engineering: what is new?; What is the best available micro and macro dental implant topography?; Can we achieve osseointegration without primary stability?; How reliable and predictable is fully guided technology?; Zygomatic implants or sinus lift for the atrophic maxilla with a dentate mandible?; Is there an ideal material for implant supported prosthesis?; Soft tissue quality and quantity: better implant longevity?; Is peri-implantitis Curable?; What Is the Best Cement for Implant Supported Prosthesis?; and more!.