20.500.12556/DKUM-95361 Korozijski parametri cirkonija v umetni slini z dodatkom želodčne kisline diplomsko delo univerzitetnega študijskega programa I. stopnje Corrosion parameters of zirconium metal in artificial saliva with the addition of gastric acid Dentalni implantati so že nekaj časa vse bolj pomemben del moderne dentalne medicine, saj se s splošnim staranjem populacije, tako kot tudi moderno konsumpcijo hrane veča potreba po možnostih za nadomestitev naravnih zob, tako iz funkcionalnega kot tudi iz estetskega vidika. Zobni implantat je sestavljen iz krone, ki predstavlja nadomeščen zob, vijaka, ki krono pritrdi v kost čeljusti in vezivnega materiala, ki krono drži pritrjeno na vijak. V okviru raziskave nas je zanimala funkcija cirkonija kot nadomestnega materiala za izdelavo vijaka zobnega implantata. Specifično, zanimala nas je korozijska odpornost cirkonija v pogojih, katerim bi bil ta vijak izpostavljen v ustni votlini ob prisotnosti želodčnega soka v slini, kar se lahko zgodi ob bruhanju oziroma gastroezofagealnem refluksu. Vzorce smo testirali z gravimetrično metodo, njihovo površino pa analizirali z elektronskim mikroskopom (SEM). Izpostavili smo jih simulirani slini z dodatkom HCl z vrednostmi pH = 1, 2, 3 ter 4 in jih pasivirali v raztopinah 24, 48, 72 in 96 ur. Iz zbranih podatkov smo ugotovili, da ima cirkonij, ki tvori tako imenovani lastni oksid (ang. native oxide) dobro lastnost repasiviranja. Najvišjo korozijsko hitrost smo zasledili pri pH = 1 po 72 urah pasiviranja, nakar sledi repasiviranje po 96 urah. Vsi ostali vzorci so najvišjo korozijsko hitrost pridobili po 48 urah izpostavljenosti v mediju in se po tem času vsi repasivirali. Najnižjo korozijsko hitrost opazimo pri pH = 2 po 72 urah pasiviranja. Sklepamo lahko, da je za to razlog puferski sistem, ki je tudi naravno prisoten v slini in očitno izrazito deluje pri pH = 2 ali pa samo termodinamsko obnašanje korozijskega sistema pri teh pogojih. Dental implants have for some time been an increasingly important part of modern dental medicine, as with the general aging of the population, as well as modern food consumption, the need for options to replace natural teeth is growing, both from a functional and an aesthetic point of view. A dental implant consists of a crown, which functions as the replacement tooth, a screw that attaches the crown to the bone of the jaw, and a bonding material that holds the crown secured to the screw. In the scope of our research, we were interested in the function of zirconium as a substitute material for manufacturing the screw component of a dental implant. Specifically, we were interested in the corrosion resistance of zirconium under conditions it would be exposed to in the oral cavity in the presence of gastric acid in saliva, which can occur during vomiting or gastroesophageal reflux. We tested the samples using the gravimetric method, and their surface was analyzed with a scanning electron microscope (SEM). They were exposed to simulated saliva with added HCl at pH values of 1, 2, 3, and 4, and passivated in solutions for 24, 48, 72, and 96 hours. From the collected data, we came to the conclusion that zirconium, which forms a so-called native oxide, has a tendency to undergo repassivation. The highest corrosion rate was observed at pH = 1 after 72 hours of passivation, followed by repassivation after 96 hours. All other samples reached their highest corrosion rate after 48 hours of exposure in the medium and repassivated after that. The lowest corrosion rate was observed at pH = 2 after 72 hours of passivation. We conclude that this is likely due to the buffer system, which is also naturally present in saliva and appears to be particularly effective at pH = 2, or possibly due to the thermodynamic behavior of the corrosion system under these conditions. cirkonij korozija umetna slina dentalni implantati želodčna kislina zirconium corrosion simulated saliva dental implants gastric acid true true false [M. Borovšak] Slovenski jezik Angleški jezik Diplomsko delo/naloga 2025-09-15 13:14:41 2025-10-28 14:07:04 2025-11-05 03:11:42 0000-00-00 00:00:00 2025 0 Maribor 0 Maribor 1 spletni vir (1 datoteka PDF (VIII, 29 str.)) 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 620.193.47:669.269(043.2) 255796227 UN_Borovsak_Martin_2025.pdf UN_Borovsak_Martin_2025.pdf 1 9C1C9E816DE0BFC95FB15BE5D8BE6A9E 87abbf1328f58987ef8f643812bf8de01bbea17a75e008c9db3fa99a24d26054 fd4afbb4-9228-11f0-9bf2-00155d000105 https://dk.um.si/Dokument.php?lang=slv&id=198469 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0