Sometimes, the nerve of the tooth begins to die, or has died. In these cases, the dead nerve must be removed so that the body can get rid of the infection. This is what a root canal entails. The tissues are accessed, and then filed out, and then filled to create a seal at the end of the root. The body will heal the rest if the seal is good. We will refer to an endodontist if the case is more complicated to create that seal. Endodontists are specialists at root canals, and can do a better job in less time for these more difficult cases.
When a tooth is lost, we can replace that tooth with an implant supported crown. We do not place the actual implants, as we want the best possible foundation for the crown, so we will refer to dentists that have much more experience in that field. We will, however, be able to make the crown that attaches to the implant. Before implants were as mainstream as today, we used to place bridges across spans that were missing teeth. Bridges do work, but they join teeth together that want to move independently, so one side of the bridge eventually loosens and the bridge fails. We also believe that it is not conservative to cut down the adjacent two teeth to replace the one missing tooth.