Aim: To evaluate the dentin microhardness of primary teeth undergoing indirect pulp capping (IPC) after partial caries removal.
Materials: Primary molars were treated with IPC, restored with self-etching primer (Clearfil SE Bond; CSE), and filled with composite resin (Filtek Z250) with (n = 10) or without (n = 7) a calcium hydroxide base liner (Dycal; Dy). After tooth exfoliation, the microhardness of the demineralized dentin remaining under the restoration (n = 17) was analyzed and compared with that of sound and carious primary dentin (n = 20). Microhardness measurements were obtained from the deepest portion of the cavity until the roof of the pulp chamber. Data were analyzed by Kruskal-Wallis test (p < 0.05).
Results: There was no difference in microhardness values at all depths between the treated groups (DY and CSE), but when the exfoliated carious teeth were included, the CSE had significantly higher values at 35-microm depth. This difference was only detected in the DY group after a depth of 200 microm. At 700 microm, there was no difference in microhardness values between all 4 groups.
Conclusions: Primary teeth that underwent IPC showed the same microhardness, regardless of the capping material used.