Prosthetic IV. addition Removable dentures I. and II. Removable dentures • Removable partial dentures • Complete denture Removable dentures - classes Class I. Dental arch with gaps (interruptions) Teeth supported (borne) dentures Class II. Reduced (shortened) dental arch Teeth and tissue supported (borne) dentures Removable dentures - classes Class Single teeth Loss of the most important abutment teeth (big gaps - more than 4 teeth) Mostly tissue (borne) dentures, sometimes teeth supported additionally Class IV. Complete denture Tissue supported (borne) Clasp - three armed cast One part for retention (going under the maximal convexity) One part for stabilization against horizontal forces (upon the maximal convexity) On arm for transmission of occlusal forces (the rest) Class I and II dentures with the metal framework Class I. denture Components: Metal framework Arteficial teeth Base Clasps Class I í dentures with the i and II metal framework Lingual plate Class I and II dentures with the metal framework connector Anterior palatal bar Posterior palatal bar 39 Sequences of operations Taking impressions (alginate. Both jaws always Sequences of operations Pouring - gypsum models. Fabrication of the individual impression tray if necessary. If not, fabrication of the bite template: ► Shellack base The bite template is necessary for The registration of the intermaxillary Relationship. It consist of the shellack base and the wax walls. Sequences of operation Registration of the intermaxillary relationship. The reg istrate Sequences of operation Preparation of the model for backup All undercuts are blocked out Also the space under the future framework Using heated wax Sequences of operations • Backup using the reversibile impression agar based material in a special flask • Pouring of this impression with -the investing material - casting model Sequences of operations Fabrication of the wax pattern of the metal framework. Influx system Sequences of operations Investment with the same investing material -a special flask. The wax is burnt out and the form is heated in a special oven. After that the casting process is performed using a special casting machine. Sequences of operation • After casting and cooling the framework is taken out, the inflow system must be cut Sequences of operation The cast is grinded, polished and adapted on the former gypsum model The final framework is tried out Sequences of operation • The arteficial teeth will be applied ace intermaxillary registrate in articulator. Arteficial teeth - acrylic Sequences of operation After trying out of the denture with wax base and teeth the denture is completed The framework with the wax pattern of the base and teeth has been put into a flask, the wax has removed and replaced with a resin dought. The resin base is polymerized using heating. Sequences of • The denture is finished, in. operation polished and tried Feedback • For which classes of removable dentures is necessary to fabricate the metal framework? • On which model is the wax pattern of the framework made? • What is the method of „lost wax" ? Feedback • Which parts does the partial removable denture consist of? • Describe the sequences of operations of these dentures. Explain the main difference between class I. and II. removable dentures. • What is the purpose of the bite template? Which part does it consist of? • Explain the term „investment".