The dentist's ability to make the patient understand the nature of the treatments is fundamental for the acceptance of treatment plans and adherence to therapeutic paths. Understanding is essential for the patient. Too often it is taken for granted that the patient understands everything, even if their comprehension has not been verified. This book aims to increase the effectiveness of communication between the dentist and the patient, especially in the case of certain therapies that are difficult to understand or where there may be an overload of information. After a brief introduction to tooth anatomy, the main interventions in implantology, periodontics, fixed and removable prosthetics, endodontics, conservative dentistry, and surgery are described.