This section is from the book "The Hygienic System: Fasting And Sun Bathing", by Herbert M. Shelton. Also available from Amazon: The Hygienic System Vol III Fasting and Sun Bathing.
Fasters who have false teeth should keep their teeth in during the fast and should bite on them sufficiently often to keep the gums tough. The gums will shrink somewhat in the general loss of weight so that the plates will not fit after the fast, until the gums have filled out again. This makes chewing, especially of uncooked foods, rather difficult, unless the gums have been kept tough.