ABSTRACT
Objective: This literature review aims to assess the causes and consequences of periodontal-endodontic lesions, as well as its clinical, radiographic and microbiological aspects. Literature review: Periodontal-endodontic lesions are often changes that affect all teeth due to the close relationship between pulp and periodontium. Many authors researched about this, but there are many disagreements on the subject, starting with the different types of classification, in which many are based on the origin of the disease, the other forms of treatment, degree of pulp involvement, among others, with the purpose of helping in the correct diagnosis. The knowledge of the etiology of the disease is extremely important, because the success of the treatment depends on the rapidity of its onset, the treatment protocol adopted and medication use. Conclusion: It is necessary that the dentists know the morphology and structure of the oral cavity, as well as the knowledge of all factors that can cause the same damage, so that they differentiate the types of periodontalendodontic lesions regarding to its origin, defining the best treatment to be followed.