The goal of this text is to provide the reader with the tools for making an informed choice among all the available therapeutic possibilities for saving a natural tooth or replacing it with or without an osseointegrated implant. The set of strategies for preserving natural teeth involves complex endodontic retreatments, resulting from previous failures that combine anatomical peculiarities and technical errors, including fractured endodontic instruments or perforations. Some of these issues can be resolved orthograde, while others necessarily require surgical intervention. Surgical endodontics plays a fundamental role in the extreme salvage of the natural tooth and must adhere to well-established rules and procedures to achieve high probabilities of success. The text also examines other prosthetic-orthodontic solutions to address cases such as agenesis, including autotransplantation, which involves using a natural tooth extracted from a different area to replace the missing tooth. A significant part of the volume is dedicated to replacing the natural tooth with an osseointegrated implant. In this section, the criteria for selection, timing, and methods to achieve optimal integration are examined, aiming for a considerable success rate in terms of implant stability in the bone and the proper relationship between the implant and its associated crown with the soft tissues. It is a comprehensive guide based on the most modern principles of dentistry, which place dental elements at the center of the rehabilitation process and consider implant components as essential support when teeth are irreparably compromised.