School of Dental Medicine, University of Zagreb, Croatian Dental Society - Croatian Medical Association
Abstract
Svrha ovog istraživanja bila je ispitati kako djeluje pomicanje vode po površini dentina vezanog za konvencionalne stakleno-ionomerne cemente. Materijal i postupci: Na ekstrahiranim trećim molarima bili su pripremljeni kaviteti petog razreda ispunjeni konvencionalnim stakleno-ionomernim cementom Fuji IX. Zatim je dio uzoraka bio jedan mjesec uronjen u umjetnu slinu, a dio 18 mjeseci. Nakon toga roka razrezani su longitudinalno i analizirani SEM-om (sekundarnim i „backscattered“ načinom) te EDAX-om. Rezultati: Nakon 18 mjeseci u materijalu su bile uočene sferične strukture kod spoja tvrdog dentina. Prazni prostori u blizini spoja tradicionalnih stakleno-ionomera i dentina uglavnom su bili u obliku „ljuske jajeta“ (iako je bilo i čvrstih). To je najvjerojatnije rezultat daljnjeg stvrdnjavanja u praznim prostorima originalnog polialkenoatnog matriksa, a događa se zbog difuzije vode iz vlažnog dentina. EDAX-ovom analizom potvrđeno je da su te formacije sastavljene od velike količine stroncija, silikata i aluminijia. Zaključak: Opisane sferične formacije mogle bi poboljšati kompresivne snage uočene kod starijih ispuna s konvencionalnim stakleno-ionomernim cementom.Objectives: The purpose of this study was to examine the effects of the water movement across dentin bonded to conventional glass-ionomer cements. Material and method: Class V cavities were prepared on extracted permanent third molar teeth, filled with conventional glass-ionomer cement Fuji IX and stored in artificial saliva for one and 18 months. After the storage time interval, the teeth were sectioned longitudinally and examined by SEM (in secondary and backscattered electron mode) and EDAX. Results: Spherical structures were noted in the material adjacent to the interface with the hard dental substances after 18 months. The air voids found next to the interface between the traditional glass-ionomer cements and dentin are mainly “egg-shell-like” (although, solid ones were also found). They are probably a result of the continuation of the setting reaction in the air voids of the original polyalkenoate matrix, which appears because of water diffusion from the humid dentin. The EDAX analysis proved that these formations consist of high quantity of strontium, silica and aluminium. Conclusions: The described spherical formations may lead to improvement of the compressive strength, which is found in old restorations with conventional glass-ionomer cements
