Crown retention with use of different sealing systems on prepared dentine.

The purpose of this in vitro study was to evaluate crown retention after using different sealing systems on prepared dentine. Ca(OH)2 suspension was used in comparison with three adhesive bonding systems (Gluma Desensitizer, Optibond FL, Prompt L-Pop). Extracted human premolars were uniformly prepared with the use of a special parallelometer (11 degrees taper, 4 mm axial length). Groups of 20 teeth each were treated with each sealing system. Then crowns were fabricated and temporarily cemented twice. Finally the abutments were cleaned and the crowns were cemented with a glass-ionomer cement Ketac-Cem. Subgroups of 10 crowns were removed with a universal testing machine following storage in distilled water either for 3 days or for 150 days. Prior to dislodging, the crowns of both groups were subjected to chewing simulation. The mean dislodgement stresses in MPa were between 4.9 and 6.9. A range test of Student-Newmann-Keuls revealed significant differences between Ca(OH)2 and Optibond FL (P < 0.05), while the storage time had no significant effect. The level of microleakage increased significantly with storage time (P < 0.05). It is concluded, that the use of Gluma Desensitizer and Prompt L-Pop did not affect crown retention as compared with Ca(OH)2, thus may be used in combination with glass-ionomer cement to desensitize prepared teeth.