Microleakage of different temporary luting agents used for cementing provisional restorations on custom cast posts and cores

Abstract

Background: This study aimed to compare the effect of four temporary luting agents on preventing
the coronal microleakage of teeth restored with custom cast post and core.
Materials and Methods: In this in vitro original study, after removing 9 mm of gutta percha from
root canals of 32 single‑canaled premolars, the acrylic resin patterns of the post and core were
fabricated. Patterns were cast with Ni‑Cr metal alloy and then cemented with glass ionomer. Using
self‑curing acrylic resin, provisional restorations were made. Then, teeth were randomly allocated
to four groups for each temporary cement including zinc oxide eugenol (Temp Bond), zinc oxide
noneugenol (Temp Bond NE), noneugenol resin‑based temporary luting agent (Temp Bond Clear),
and noneugenol urethane methacrylate polymer‑based temporary luting agent (Dento temp). Teeth
were subjected to thermocycling, immersed in silver nitrate for 6 h and then sectioned. The amount
of dye penetration in the margin of provisional crown and into the coronal part of the root canals
was measured using a stereomicroscope. Data were analyzed using the Kruskal–Wallis and Dunn
tests with significance level of 0.05.
Results: All the luting agents showed some degree of microleakage (Group 1 showed the most
microleakage). According to the pair comparison between the groups, Group 1 revealed a significant
difference with others (P < 0.05). Furthermore, Group 2 showed more microleakage as compared
to Group 4 (P = 0.037).
Conclusion: Temp Bond showed the highest microleakage as compared to other luting agents.
Furthermore, Temp Bond NE revealed a weaker sealability as compared to Dento temp.
Key Words: Dental cement, nonvital tooth, temporary dental restoration