A Method for Testing Abrasive Wear of Aesthetic Prosthetic Materials

Trenje i trošenje zbivaju se na dodiru tvarnih površina koje su više ili manje hrapave. Tijekom abrazijskoga trošenja nastaje istiskivanje materijala prouzročenog tvrdim česticama koje prave pritisak prema površini, ili kližu duž nje (trotočkasto abrazijsko trošenje), ili pak tvrdim izbočinama (dvotočkasto abrazijsko trošenje). Zahtjevi za estetskom opskrbom grizne plohe postavljaju pred kliničara problem izbora materijala za fasetiranje. U ovome članku opisana je metoda za ispitivanje abrazijskoga tro- šenja parova zub-protetski materijal za fasetiranje. Da bi se ocijenila ta metoda ispitana su dva različita protetska materijala za fasetiranje (polimerni materijal SR Chromasit, Ivoclar i glinična keramika, Sign Ivoclar) na modificiranom Taber abrazeru, u suhim uvjetima. Dobivene su znatne razlike u tragovima trošenja na uzorcima ispitivanih materijala. Testirana metoda omogućuje ispitivanje uzoraka različitih materijala međusobno ili u paru s prirodnim zubom, pod različitim opterećenjima te s postojanjem trećeg tijela ili bez njega (hrane ili umjetne sline), što je u kliničkoj praksi vrijedan podatak pri izboru vrste konstrukcije i materijala za fasetiranje.Friction and wear occur due to the contact of surfaces which are more or less rough. During abrasive wear the extrusion of material occurs, caused by hard particles which apply pressure toward the surface or slide along it (three-body abrasive wear) or by hard protrusions (two-body abrasive wear). Because of demands to provide a satisfactory aesthetic mastication surface the clinician is faced with the problem of the choice of material for veneering. The article describes a method for testing abrasive wear of pairs of tooth-prosthetic material for veneering. In order to test the method two different prosthetic veneering materials were tested (polymer material SR Chromasit, Ivoclar and Clay ceramic, Sign-Ivoclar) on a modified Taber abraser, in dry conditions. Significant differences were determined in the wear scars on specimens of the tested materials. The method enables the testing of specimens of different materials mutually or in a pair with a natural tooth, under different loading and with or without a third body (food or artificial saliva), which in clinical practice represents valuable data during the choice of the type of construction and veneering material

Wear Characteristics of Esthetic Prosthetic Materials

Poznavanje triboloških svojstava estetskih protetskih materijala nužno je u svakodnevnoj stomatološkoj praksi. Usavršiti novu, originalnu, metodu i konstruirati uređaj za ispitivanje triboloških svojstava gradivnih protetskih materijala, ispitati tribološka svojstva različitih estetskih protetskih materijala te ispitati međusobno ponašanje materijala tribološkog para: prirodan zub - protetski materijal. Istraživanje je rađeno na modificiranom uređaju “Taber abraser”, na uzorcima šest različitih estetskih protetskih materijala. Trošenje je najmanje za uzorke glinične keramike (Creation i d.Sign), a najveće za polimer (Chromasit) te ceromer (Targis). Najmanji faktori trošenja određeni su, također, za glinične keramike. Istraživanje je rezultiralo razvojem nove metode i uređaja za ispitivanje triboloških svojstava protetskih materijala.Knowledge of wear characteristics of esthetic prosthetic materials is essential in everyday dental practice. To establish a new, original, method and produce a device for examining wear characteristics of constructive prosthetic materials, to assess the wear characteristics of different esthetic prosthetic materials and to examine the relationship in a wear pair: natural tooth - prosthetic material. The study was performed on a modified device “Taber abraser” on samples of six different esthetic prosthetic materials. The wear is smallest for samples of alumina ceramics (Creation and d.Sign), and greatest for polymer (Chromasit) and ceromer material (Targis). The smallest wear factors were established for alumina ceramics as well. The study has resulted in the development of a new method and new device for examining the wear characteristics of prosthetic materials