The materials of the article contain a description of the clinical and radiological picture of peri-implantitis. The operation of dental implantation was performed at the beginning of the retention period in orthodontic treatment. Plastic crowns on temporary abutments were made a few days after the surgical stage. As a result of immediate occlusal load and installation of dental implants in the early stages of the retention period of orthodontic treatment, their disintegration occurred.