Prosthodontics is the dental specialty pertaining to the diagnosis, treatment planning, rehabilitation, and maintenance of the oral function, comfort, appearance, and health of patients with clinical conditions associated with missing or deficient teeth and/or maxillofacial tissues by using biocompatible substitutes.
(Glossary of Prosthodontic terms 9th ed.)
Dentures, partials, crowns, bridges, veneers, and implants are all involved in prosthodontic treatment. This specialty requires three years of advanced training after four years of dental school.
Simply put - It's looking at the big picture to restore your smile and chewing ability.