Single-tooth implants can be used in people who are missing one or more teeth. An implant is surgically placed in an opening that is made by your dentist in the jawbone. After the implant integrates (attaches) to your bone, it acts as a new "root" for the crown that will be replacing your missing tooth. A crown (cap), which is made to look like a natural tooth, is attached to the implant and fills the space left in the mouth by the missing tooth.
For this procedure to work, there must be enough bone in the jaw, and the bone has to be strong enough to hold and support the implant. If there is not enough bone, be may need to be added with a procedure called bone augmentation. In addition, natural teeth and supporting tissues near where the implant will be placed must be in good health.
Second photograph shows the need to do crown cutting for reducing the size of the tooth (abutment) for replacing the missing tooth. On the contrary in the first photograph the implant takes the root form of the natural tooth thereby eliminating the need to do crown cutting on the adjacent teeth thus maintaining the intact form of the existing dentition.