Is it permissible to extract healthy teeth—or those whose structure is sometimes healthy—in order to design and install removable artificial dentures, or with the aim of installing a complete set to avoid future problems, and are these cases considered a necessity that permits such action?

There is no harm in installing artificial teeth when needed or necessary, such as due to damage or breakage, because it falls under the category of medical treatment and removing a defect, not beautification. However, it is not permissible to extract a healthy tooth or any healthy organ unless its removal achieves a greater benefit or averts harm, such as pain relief. Therefore, tooth extraction is not limited to necessity alone, but is permissible for need and benefit.