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 partial denture (besides expense) is that new teeth and new denture base can easily be added to an existing denture.
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. They are often considered as a temporary solution. The acrylic denture base tends to be brittle, and due to their irregular shape, these partials tend to break frequently, especially those made for the lower arch.
In order to counteract their tendency to break, the acrylic is usually built fairly thick which some patients may find difficult to adapt to.
The denture base rests only on the gums, and even though they are much more stable than full dentures, they are much less stable than the more permanent cobalt chrome based partial dentures which use clasps to gain support from the teeth.
As the gums recede the false teeth tend to sink below their original level making it necessary to reline them frequently, and sometimes even to reset the teeth which adds to their expense.