The interrelationship between endodontic and periodontal diseases has been a subject of speculation, confusion and controversy for many years due to its complex nature and can have a varied pathogenesis. It is very essential to make a correct diagnosis thorough understanding and scientific knowledge of these lesions to perform restorative, endodontic or periodontal therapy. Therefore, to achieve the best outcome for these lesions, a multi¿disciplinary approach should be involved. This book presents a detailed literature serach and discuusion on the pathogenesis, etiology, diagnosis and management of the same.