Patent RU-2310419-C1 (RU)
Inventor: GALONSKIJ VLADISLAV GENNAD EVI
IPC: A61C13/007
Filed: 2006-02-10
Granted: 2007-11-20
Abstract: FIELD: medicine. 
     SUBSTANCE: method can be used for making hollow artificial limb/obturator for patients having defects of soft and hard palate and partial or total maxillary adentia. Mould of defect is made by individual spoon; working model is made of high-strength gyps; borders of basis are marked; working model is duplicated and copy of it is made of refractory mixture. Opening with diameter of 10-15 mm is formed in projection of dome of obturator at basis side of working model; opening intends for communication with cavity of obturator. Wax reproduction of metal part of basis, having hollow volumetric obturator, is formed by means of reduction of model by one layer of clasp wax of 0,3 mm thickness to form deepening corresponding to defect and forming cap-shaped plate which cover deepening on palate part and modeling soft and hard palate; plate is fixed with wax along edges. Basis restrictor is made along vestibular end and at palate side of wax blank in form of strap with width up to 2 mm. Arc-shaped braces are made in projection of vertex of alveolar appendix to connect plastic and metal parts of artificial limb made of metal blanks. Then through opening in cavity of obturator is filled with refractory mixture, which is fixed against base by shank; gating system is created and casting form is made. Bottle on vibration table is filled with refractory mixture and is stored until it hardens completely; wax is subject to melting at 300° during 30 minutes; casting form is subject to baking until it reaches temperature of 950°C during 30-40 minutes. After that temperature is increased up to 1230-1250°C for 20-30 seconds and the whole system with bottle is driven into rotation. After molding is finished, bottle is subject to cooling until it reaches room temperature; cast is removed from bottle and cleaned; funnels are cut away and refractory mixture is removed from cavity. Metal frame is subject to polishing and to adjustment in mouth cavity. After central relation of maxillas is found and working and ancillary models are fixed inside anatomical articulator, wax analog of alveolar appendix is modeled on metal part of basis, which appendix compensates atrophy of tissues of the appendix, and artificial dentures are mount. Modeled prosthetic appliance is plastered into dish.  Model with prosthetic appliance is plastered into lower part of dish; opening in dome is preliminary closed. Then top part of dish is mounted and filled with liquid plaster onto vibration table; dish is withstood under pressure until plaster gets completely hard. After wax is removed by means of evaporation, dish is open; surface of top plaster cast is isolated by separation lacquer. Top part of dish is filled with doughy acryl plastic mass; halves of dish are connected and subject to pressing in vertical direction; then plastic mass is subject to polymerization. Artificial denture is removed from dish, and then it is ground and polished. Then it is adjusted in mouth cavity to keep opening on dome of obturator open. 
     EFFECT: reduced weight of structure; ability of keeping temperature perception of tissues of prosthetic bed; higher strength and prolonged service life; high precision of conformity to prosthetic bed; prevention of atrophy of tissues; restoration of language and mastication function. 
     22 dwg, 2 ex, 2 tbl