Affectionately known in dentistry as a "flipper", this is the least expensive of all the removable partial dentures.  The one pictured on the right replaces 4 missing teeth, leaving spaces for 7 natural teeth.  Two  of the natural teeth are clasped with wrought wire clasps which are cured into the structure of the denture base.   

                     The pink plastic of the denture base is brittle acrylic, the same material used to make standard full dentures.  The largest single advantage to this type of RPD (aside from the cost) is that new teeth and new denture base can easily be added to an existing treatment RPD.  These are frequently fabricated even if the remaining teeth have existing decay or periodontal disease and their prognosis is doubtful.  If later in the course of treatment some of the existing natural teeth are extracted for any reason, new false teeth can be added quickly to the partial, maintaining the patient's appearance.  In spite of the fact that they are considered a temporary solution, many people keep this type of appliance for many, many years, because as long as they are properly maintained, they look outwardly as good as the more expensive permanent appliances.