Transdentinal cytotoxicity of resin-based cements on odontoblast-like (MDPC-23) and human dental pulp cells.

Statement of problem: The variety of resin cements available for cementing fixed prostheses raises concerns regarding their cytotoxicity as the components of these materials may interact with pulp cells and induce adverse biological responses. Therefore, assessing the biocompatibility of these cements is essential to ensure their clinical safety.

Purpose: The purpose of this in vitro study was to evaluate the transdentinal cytotoxicity of resin-based materials used for cementation of prosthetic components on odontoblast-like cells (MDPC-23) and human dental pulp cells (HDPCs).

Material and methods: Dentin disks obtained from 60 intact human third molars were adapted to fit into artificial pulp chambers (APCs). Then, resin-based cements were applied to the occlusal surface of these disks (n=6/treatment) to establish the groups: negative control - no treatment (NC); Single Bond Universal (positive control - PC); RelyX Luting 2; RelyX U200; and RelyX Ultimate. After 24 hours, the extracts (culture medium containing components of the materials diffused through the disks) were collected and applied to MDPC-23 cells and HDPCs previously seeded (1×10⁴ cells/compartment) in 96-well plates. Cells were assessed for viability (VI; AlamarBlue and Live or Dead), adhesion and spreading (A/S F-actin), alkaline phosphatase (ALP) activity, and mineralization nodule (MN) deposition (ANOVA/Tukey; α=.05).

Results: Reduction in VI, A/S, ALP, and MN occurred in the groups in which resinous materials were used, except for the RelyX U200 group. The RelyX Luting 2 group showed the most pronounced negative effects compared with the NC group. The cytotoxicity of the materials tested was more intense for MDPC-23 cells than in HDPCs.

Conclusions: RelyX U200 was the only dental material among the resin-based cements tested that caused no transdentinal toxicity to MDPC-23 cells and HDPCs.