Abstract
Purpose
To
evaluate the effect of temporary cement cleaning methods on the
retention of cemented crowns using zinc phosphate cement and
resin-modified glass ionomer cement.
Materials and Methods
Forty
titanium specimens were fabricated to simulate prepared molars with
minimally retentive taper. The Ni-Cr cast crowns were fabricated,
temporarily cemented, and separated. The specimens were divided into
four groups according to the temporary cement cleaning method (n = 10)
as follows: control group (no temporary cementation), orange solvent
group, ultrasonic cleaning group, and air-abrasion group. After the
cleaning procedures, the specimens were cemented with definitive cements
(zinc phosphate cement and resin-modified glass ionomer, RMGI, cement)
and subjected to thermocycling (5000 cycles, 5-55°C, dwell time, 10
seconds). The tensile bond strength of each specimen was measured using a
universal testing machine, and the results were analyzed using the
Kruskal-Wallis and Mann-Whitney U test (α = 0.05).
Results
When
cemented with zinc phosphate cement, the statistical analysis showed
that the value of the air-abrasion group was significantly higher than
those of the other groups (p < 0.01). There was no
statistically significant difference among the other groups. When
cemented with RMGI cement, the air-abrasion group showed the lowest
value, and the control group showed the highest value (p <
0.01). The difference between the ultrasonic cleaning group and the
orange solvent group was not statistically significant.
Conclusion
The
use of temporary cement did not have a significant influence on
retention of permanently cemented crowns when zinc phosphate cement was
used for permanent cementation. Airborne-particle abrasion after
provisional cementation improved retention of crowns cemented with zinc
phosphate cement; however, the use of temporary cement significantly
decreased retention of permanently cemented crowns when RMGI cement was
used regardless of the temporary cement cleaning method.
Comments