Constructing a new set of dentures is not always as straight forward as taking a quick impression of one’s mouth. First, the dentist must check the tissues for any pathology. It is certainly not a good idea to build a denture over a tumor or cancer. The next thing to check is the condition of the ridges of the gums themselves. If there is inadequate bone to allow for good retention and stability of a denture, then a bone graft may need to be considered. Artificial bone substitutes, cadaver bone, or pieces of the patient’s own bone can be placed under the gums surgically to add enough bulk to comfortably wear a denture. If there are bumps of bone called tori or severe bony undercuts that rigid plastic could not snap around, then they need to be surgically removed. The dentist peels a flap of gum tissue that is over the bony prominence and grinds the offending piece of bone off and smooth the area. In other cases, there could be flabby, moveable tissue or even extra folds of gums which would make a denture unstable. This would also have to be surgically removed. By properly preparing a good gum foundation, a very well fitting set of dentures can be constructed.