SEM observations of the attachment of human periodontal ligament fibroblasts to non-demineralized dentin surface in vitro.

PURPOSE The purpose of this investigation was to study in-vitro the attachment behavior of human periodontal ligament (HPDL) fibroblasts to nondemineralized dentin surface using scanning electron microscope. STUDY DESIGN Thirty root slices of freshly extracted human teeth of 4 mm thickness as well as six 5x5 mm glass slides used as a control were used in this study. The dentin surface of the root slices was not treated with any chemicals to remove the smear layer. The root slices and the glass slides were placed in tissue culture clusters and an amount of 1 ml of HPDL fibroblast cell suspension was placed over the dentin surface of the root slices and the glass slides. They were then placed into an incubator at 37 degrees C and 100% humidity for 4, 24, and 72 hours. At the end of the incubation, the cells were fixed with glutaraldehyde and examined microscopically. RESULTS Different shapes of fully spread cells were seen. The cells were attached firmly to the dentin surface by the cytoplasmic extension of the lamellipodia and microvilli which were seen extending inside the opening of the dentinal tubules. CONCLUSION It was concluded that the human dentin surface provided an excellent surface for attachment of periodontal ligament fibroblasts. In addition, the smear layer did not affect the cell attachment.