Identify a contraindication for using an RPD.

Severe residual ridge resorption stands out as a contraindication for the use of a removable partial denture (RPD) because it significantly compromises the underlying bony support for the prosthesis. When the residual ridge has undergone extensive resorption, it can result in insufficient retention and stability of the RPD. This leads to challenges in achieving proper fit, causing discomfort and potentially resulting in functional issues for the patient.

In these cases, the lack of sufficient bone volume may hinder the RPD's ability to adequately distribute forces during chewing, increasing the risk of further bone loss or soft tissue problems. In contrast, minor tooth mobility might still allow for the successful use of an RPD, existing dental implants can provide additional support for prosthetic appliances, and good oral hygiene is actually beneficial for the longevity and success of removable partial dentures.