Inflammatory processes around dental implants are a common problem for patients with dental implants. The cause of these problems is induced by multifactorial stimulus e.g., microbes, smoking, host response, foreign body reactions and metal particles. Metal elements from the implants induces an immune reaction which is pro-inflammatory. These reactions in combinations with other factors can aggravate peri-implantitis and in worst case threaten the survival of the implant. It is important to have knowledge about the immune system and inflammatory reactions, which should be taken in considerations when planning for rehabilitation with dental implants. Metal- and ceramic particles will be present in the peri-implant tissue, but without other stimuli the immunological reactions from these particles will be low. For long-time survival of dental implants practitioner should use implants with cautions at patients with a previously known periodontal history and address the factors that can be controlled, oral hygiene and smoking habits. If these factors are address dental implants have a very high success rate, when used to rehabilitate patients with missing teeth.