Author :
Bennett, B. ; Puckett, A. ; Fitchie, J.
Author_Institution :
Univ. of Mississippi Sch. of Dentistry, Jackson, MS, USA
Abstract :
Summary form only given. The objective of this study was to evaluate the change in Barcol hardness of five different hybrid glass ionomers (GI) after storage in distilled H2O at 37°C. The materials were (A) Encapsulated and (B) Handmixed Variglass (Caulk Dentsply, Milford, DE), (C) Vitremer (3M, St. Paul, MN), (D) Fuji II (GC Corp., Tokyo, Japan) and (E) Photacfil (ESPE Premier, Norristown, PA). Barcol hardness measurements were taken on all the samples after twenty-four hours, 1 week and 1 month of aging. Comparison of the initial hardness using ANOVA (p<0.05) revealed no significant differences. However, materials A and B showed a decrease in hardness after 1 week of storage. In contrast, materials C, D and E showed a significant increase (p<0.05) in hardness after storage. Based upon these results, it may be concluded that materials C, D and E continue to react during aging resulting in a harder material. In contrast, the materials A and B do not continue to react but actually become softer due to plasticization by absorbed water. The additional reaction of materials C, D and E is most probably the result of further ionic crosslinking which may be facilitated by water absorption
Keywords :
ageing; glass; hardness; prosthetics; water; 1 month; 1 week; 24 hour; 37 degC; ANOVA; Barcol hardness; Fuji II; H2O; Photacfil; Vitremer; absorbed water; aging characteristics; distilled H2O; encapsulated variglass; four hybrid glass ionomers; handmixed variglass; hardness decrease; hardness increase; initial hardness; ionic crosslinking; plasticization; softer; storage; water absorption; Absorption; Aging; Analysis of variance; Dentistry; Glass; Manufacturing; Material storage; Steel; Strips;
