Dental implants are not suitable for patients suffering from heart disease, blood disorders, diabetes, thyroid dysfunction and epilepsy, or for those who are too weak to tolerate surgery; patients under the age of sixteen are also not suitable for implants because their dental beds are not yet fully grown. Otherwise, healthy adults who are generally able to undergo routine extractions can consider dental implants, which have no upper age limit; as long as they are in good health, there is no restriction on how old they can be. Dental implants are the closest to natural teeth and can be single tooth implants or multi-tooth implants. In addition, on the implant abutments, fixed dentures can be made as well as removable dentures.