Stages of Fabrication for Dentures
- RPD should be planned using a surveyor and diagnostic casts
- Stock trays and alginates allow preliminary impressions to be made. Alginate impressions are poured in either regular yellow stone or a fast-setting stone, such as Whip Mix Snap-Stone™ (Whip Mix Corporation ) which allows separation in five minutes
- Most complete denture impressions include border moulding
- Most RPD impressions are made without border moulding, using stock trays and alginate impression material
- Class I, II and IV RPDs (both tooth- and soft-tissue supported) require border moulding in order to achieve excellent adaptation to soft tissues. Alginate in stock trays is usually insufficient
- Some Class III RPD impressions can be made quite successfully in alginate and stock trays as these RPD do not rely on soft tissue support for resistance to occlusion
Occlusal scheme and interocclusal records
- Occlusion should be checked and adjusted if required before impressions are made. If enough teeth are present to allow hand articulation of casts, interocclusal records are not needed. If registration of casts is needed, fast-setting, filled, addition reaction silicone is excellent (example: Blu-Mousse® Super-Fast 30 second set)
- Occlusal rims (made from resin and wax) are useful before final casts are sent to the laboratory for framework construction
- Occlusion rims are useful for many Class I, II and IV RPD and frequently also used at the framework try-in stage. Sometimes, they are useful before final casts are sent to the laboratory for framework construction
- The dentist must decide with the jaw registration record whether a conformative or reorganised occlusal scheme is required
Tooth colour and form
- Wear-resistant resin teeth (examples: IPN® or SLM®, Dentsply; Isosit™, Ivoclar Vivadent; Vitapan®, Vident™ - A Vita company) are suggested. These teeth provide several years of service before needing replacement
- Porcelain teeth are generally avoided unless opposing a full denture which also has porcelain teeth
Wax-up and Try-in stage
Once the teeth and occlusal registration have been set-up in the lab, the dentist will verify the aesthetic and functional aspects of the prosthetics.
Process and finishing
Both standard and customised characterisation are available for the final finish of the restoration.
Replacement of RPD
RPD with resin teeth last about five to eight years by which time the teeth usually are significantly worn, there have been bony and soft tissue changes and the RPD is not touching opposing teeth.