Additional Study Information: This study is for patients who have previously been treated with dental implants and then had metal posts screwed into the dental implant and artificial teeth attached to the posts. This study is being carried out to evaluate a specific type of metal posts called ATLANTIS abutments, which you have already in your mouth. These posts are manufactured by DENTSPLY Implants and have been available on the US market since 1996. In this study we will collect information and events that have already taken place. This study involves only one visit to the clinic. During that visit we will collect and evaluate information related to your artificial teeth that are attached to the dental implant via the ATLANTIS abutment; these teeth will be referred to as study artificial teeth. You may have other artificial teeth attached via other types of posts but those artificial teeth will not be evaluated in this study We will evaluate the performance and status of the metal post in your mouth. To evaluate your post we will do procedures and tests that are considered routine when it comes to implant follow-up care.