As the number of patients requesting implant treatment continuously grows, it is expected that the number of patients affected by periimplantitis will also increase. Depending on the inflammatory process level affecting the bone, the clinician decides whether the development of the inflammation inside the bone can be stopped, and tissues can be regenerated, or the explantation is needed. The key factors in the decision are: patient’s wishes, medical condition of the patient, extent of the defect, aesthetics and the possibility of plaque control following treatment. The aim of this review article was to define the factors leading to the occurrence of periimplantitis, diagnosing and treatment of peri-implantitis. Recently published scientific and professional literature on PubMed has been found using keywords and therefore reviewed. 97 papers have been found. Research results show that smoking and previous records of periodontal disease are an important factor leading to failure. In patients treated with intravenous bisphosphonates for osteoporosis, the incidence of complications is higher. Diabetes, cardiovascular diseases, head and neck radiotherapy and chemotherapy are listed as risk factors for the occurrence of periimplantitis. There is no data reporting that a certain diameter, type or length of the implant is better than the others. Most of the research papers report that the maxilla is less favorable for the placement of implants, than the mandible. Single tooth implants are a better solution than the bridges. Although there is no definite evidence on superstructure retaining modality, it seems that peri-implantitis occurs less frequently in screw-retained implants. One of the main local factors for the occurrence of peri-implantitis is cement residue. Long lasting positive results can be achieved with all types of moderately rough implant surfaces.