RETENTION OF FIXED IMPLANT PROSTHETIC RESTORATIONS

Abstract

Pričvršćenje suprastrukture završni je postupak u implantoprotetskoj terapiji. Svaki implantološki sustav sastoji se od endosealnog dijela, nadogradnje implantata i suprastrukture koja može biti mobilna ili fiksna. Ovisno o vrsti i planu implantoprotetske terapije moguće je protetski nadomjestak cementirati ili pričvrstiti vijkom. Takva odluka zahtijeva dobro poznavanje anatomije periimplatantnog tkiva, implantoloških sustava, radiološke dijagnostike, a posebice CBCT-a (engl. cone beam computed tomography), kirurških tehnika te vrste i mehanike spojeva implantata i nadogradnje. Koji je način pričvršćenja bolji ostaje proturječno. Cementiranjem nadomjeska osigurava se stabilan i estetski povoljan način pričvršćenja, ali zaostatni cement oko vrata implantata može uzrokovati periimplantitis i gubitak implantata. Za razliku od cementiranih radova, pričvršćenje vijkom omogućava skidanje i vraćanje nadomjestka te uklanja opasnost periimplantitisa zbog nedostatka cementa. Međutim, djelovanjem žvačnih sila na otvoru vijka može doći do pucanja protetskog nadomjestka pa često dolazi do neuspjeha zbog gubitka vijka. U ovom radu bit će opisani sustavi cementiranja i pričvršćenja vijkom te njihove prednosti i mane, kao i moguće komplikacije ove terapije.Affixing dental prostheses is the final step in dental implant prosthetic therapy. Dental implants consist of dental fixture or implant, abutment and dental prosthesis, which can be mobile or fixed. Depending upon the type and course of dental implant prosthetic therapy dental prostheses can be attached either by screw or cement. This decision is based upon the indepth knowledge of the anatomy of the mucous membranes and the jaw (implant site tissue), implant systems, x-ray diagnostics, especially CBCT (cone beam computed tomography), surgical techniques, as well as the types and mechanics behind the implant and permanent crown attachments. There is still debate around which type of prosthesis/crown attachment is the best. A crown cemented to the implant makes for a stable and aesthetically pleasing crown attachment, however the leftover cement around the base of the implant may cause peri-implantitis and loss of the implant. A crown attached by screw allows for easy removal for repair or replacement, which is impossible with the cement attached crown, and it also removes the threat of peri-implantintis due to absence of cement. However, due to physical forces, prosthetic crown may chip or fracture and there is a more frequent failure rate due to loss of a screw. The many advantages and disadvantages with both methods are explained in this paper, in addition to possible complications