One of the problems with the complete loss of teeth is the adaptation to chewing with dentures which are acrylic (plastic) prostheses which rest on the gum with weak support and very little retention. This adaptation is all the more difficult with prostheses for the lower jaw where the tongue contributes to creating greater instability for the denture. In addition, over the years, the loss of bone and gum associated with the loss of teeth increases and involves relining or making new larger and larger dentures to fill the missing space. Retention and stability become even more compromised.

Thus, studies have made it possible to replace all of the missing teeth by placing dental implants in specific places to affix a porcelain bridge which would cover all the teeth of an arch (jaw) to maximize retention and chewing ability. This is called a fixed prosthesis on implants. The prosthesis is said to be fixed because it is permanently cemented on the implants. It has the advantage of being more aesthetic and more solid, because it is made of porcelain and not acrylic.