# Effect of Indirect Pulp Capping Materials On Regional Dentin Seal

## TL;DR

This study tested how different pulp capping materials affect the bond strength to dentin, finding that most materials do not harm the surrounding dentin seal.

## Contribution

The study provides new empirical evidence on the regional dentin seal effects of various indirect pulp capping materials.

## Key findings

- Only Kerr Life significantly reduced peripheral dentin seal.
- All materials showed increasing bond strength from the IPC area to the periphery.
- Hydraulic cements do not negatively affect the peripheral dentin seal.

## Abstract

Purpose: The aim of this in-vitro study was to evaluate the effect of different indirect pulp capping (IPC) materials on bond strength to surrounding dentin.

Fifty-six human third molars were used in this study. Occlusal dentin of 42 teeth was exposed. Dentin surfaces (n = 6) were left uncovered (control) or received a 1 × 1 mm central IPC (KL: Kerr life, DY: Dycal, TC: Theracal LC, CL: Calcimol LC, BD: Biodentine, and PR: ProRoot MTA) and were then bonded with Scotchbond Universal adhesive and restored with a composite resin build-up (Filtek™ Z250). After 24 h of water storage, the specimens were cut into sticks, which were marked red (1 mm distance from IPC spot), green (2 mm distance), and blue (3 mm distance). Consequently, µ-TBS tests were performed and analyzed using one-way ANOVA (P < 0.05) for normal distributions and Mann–Whitney U-test (P < 0.05) for non-normal distributions. Pretesting failures were recorded as 0 MPa. Fracture modes were analyzed under a fluorescence microscope, and interfaces and surfaces of 14 additional specimens were visualized under a scanning electron microscope (SEM).

A significant reduction in peripheral seal was only observed for KL (Mann–Whitney U-test, P < 0.05). All groups showed increasing bond strengths from the IPC area to the periphery, indicating a certain contamination potential of IPC materials.

IPC materials being applied in very deep cavity areas except Kerr Life do not harm peripheral seal to dentin. Especially, hydraulic cements can be used without a negative effect on the peripheral dentin seal.