Marginal Adaptation and Cytotoxicity of Bone Cement Compared with Amalgam and Mineral Trioxide Aggregate as Root-end Filling Materials

IntroductionBone cements have a well-established place in the practice of orthopedic surgery. It has many characteristics that make it well-suited as a root-end filling material. The purpose of this study was to evaluate the marginal adaptation and cytotoxic effect of polymethylmethacrylate (PMMA) bone cement, mineral trioxide aggregate (MTA), and amalgam as root-end filling materials.MethodsThirty extracted human single-rooted teeth were cleaned, shaped, and obturated with gutta-percha and AH 26 sealer. The roots tips were removed; root-end cavities were prepared and filled with the 3 tested materials (bone cement, MTA, and amalgam). Impressions of retrofilled root ends were taken by polysiloxane impression material, and positive replicas were fabricated by using epoxy resin. The original roots were longitudinally sectioned into 2 halves; both the replicas and longitudinal sections were prepared for scanning electron microscope to measure the gaps at the material/dentin interface. Human periodontal ligament fibroblast tissue culture was used to assess the cytotoxicity of the 3 tested materials.ResultsThe obtained data revealed that both bone cement and MTA exhibited a better adaptation to the dentinal walls than that of amalgam. Also, the cytotoxicity testing showed that bone cement had a comparable cytotoxic effect on fibroblast cells with MTA; both root-end filling materials showed less cytotoxicity than that of amalgam.ConclusionsPMMA bone cement could be considered as a promising root-end filling material.