dentition which will later be added in the edentulous areas the completed appliance 15 shown in fig3 is then removed from the model 17 and inspected if the bonds are complete and no gaps exist between the joined elements the appliance 15 is positioned over the model 17 to check the fit if the bar 19 was under a strain when bonded to the clasps or if the clasps were under a strain when formed around the anchor teeth the resiliency of these parts will cause them to move when removed from the model accordingly it will be necessary to reheat these parts and make minor adjustments in their shape so that they will perfectly fit the model without the application of any stresses to the parts naturally any misalignment between the clasps and the existing dentition will cause forces to be exerted on the dentition when the appliance is inserted in the mouth of the wearer and these forces could cause the loosening and loss of the anchor teeth any contact point between the bar and the tissue in the mouth could cause extreme discomfort and the development of sores however due to the heat softenable nature of the plastic these problems can be avoided by fine adjustment and repeated trial of the appliance in the master model when the fit of the appliance in the model is satisfactory the plastic appliance may be tried in the mouth of the wearer this provides a double check on the quality of the original impression and the formation of the master model from the impression if the plastic appliance fits the model.