What is the X in X-mas?
prosthodontics pros·tho·don·tics (prŏs'thə-dŏn'tĭks)
The branch of dentistry that deals with the replacement of missing teeth and related mouth or jaw structures by artificial devices.
dental specialty concerned with restoration and maintenance of oral function, appearance, and comfort by use of prostheses. The oral prostheses replacing teeth may be removable dentures or partial dentures or permanently fixed tooth prostheses, connected to remaining teeth or implanted in the alveolar bone. Other prostheses include crowns and caps that replace the outer portions of teeth and protect the remaining structure. Prosthodontics also provides oral prostheses to correct deformities, such as cleft palate, and to replace alveolar bone in order to provide underlying support for dentures.