An in vitro evaluation of two resin-based sealers on proliferation and differentiation of human periodontal ligament cells.

AIM: To evaluate the effects of a polymethyl methacrylate resin-based sealer [Superbond sealer (SB)] on the proliferation and osteogenic differentiation of human periodontal ligament cells (HPDLCs) in vitro, compared with a methacrylate resin-based sealer [Epiphany SE sealer (EP)].

METHODOLOGY: Human periodontal ligament cells were obtained from of healthy third molar teeth of two participants with informed consent. To determine the effects of the eluent from set resin sealers on HPDLCs, the 7-day-washed (washed) or non-washed freshly prepared (fresh) set SB or EP discs were prepared. Cells cultured on these discs were evaluated by the WST-1 proliferation assay and scanning electron microscopy (SEM). The osteogenic differentiation of HPDLCs on washed SB discs was then evaluated by gene expression analysis of osteopontin (OPN) and osteocalcin (OCN) by using quantitative RT-PCR.

RESULTS: Human periodontal ligament cells exhibited growth on washed SB discs, whereas fresh SB and EP discs and washed EP discs inhibited proliferation of HPDLCs. SEM observation revealed that HPDLCs tightly attached and spread on the surface of washed SB discs, whilst no HPDLCs were observed on the surface of fresh and washed EP discs. Furthermore, HPDLCs significantly upregulated gene expressions of OPN and OCN when cultured on washed SB discs in osteogenic differentiation medium for 2 weeks.

CONCLUSIONS: Although Superbond sealer initially exerted cytotoxic effects on HPDLCs, these effects were reduced during washing for 7 days compared to EP, which continued to be cytotoxic even though the specimens were washed for the same period of time. Washed Superbond allowed HPDLCs to differentiate into osteogenic cells.