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Cell migration, attachment, and orientation of cultured human gingival fibroblasts (HGF) were measured in relation to four types of specimens: Ti-6Al-4V alloy discs with either ground surfaces or porous structured surfaces, and Zr alloy discs (Zircalloy 2) with either ground surfaces or surfaces modified by being heated to form a thicker oxide cover. Surface-demineralized and non-demineralized root slices were used as controls. Initial cell attachment was measured by means of a 51Cr assay, and cell attachment and orientation following migration by an assay that measures development of the resulting refractile material in relation to the specimen. No significant difference between initial cell attachment to Ti alloy and control demineralized root slices could be detected after one hr using the 51Cr assay. However, with the second assay, cell attachment and orientation at three, seven, 10, and 14 days were significantly higher in relation to surface-demineralized root slices than to all of the metal discs and the non-demineralized root slices. While cell attachment to the surface-ground Ti alloy discs appeared to be higher than that to the porous-surfaced Ti alloy discs at three days and seven days, cell orientation to the porous-surfaced Ti alloy discs and the non-demineralized root slices at days 7, 10, and 14 was greater than that to all of the other metal discs. These data suggest that surface geometry could affect attachment and orientation of cells in vitro. [ABSTRACT FROM AUTHOR]

Surface demineralization of tooth root surfaces has been shown to improve re-attachment of cells and to promote tissue reconstruction following periodontal surgery. Exposure of collagen fibers has been thought to facilitate migration, attachment, and orientation of fibroblasts on the root surface. However, using an in vitro assay, we have found that both attachment and orientation of human gingival fibroblasts on demineralized dentin surfaces are further improved following digestion of the exposed collagen with bacterial collagenase. In contrast, pronase and trypsin digestion of the surface collagen had no significant effect, whereas heat denaturation had an inhibitory effect. Dissociative extraction of the demineralized dentin slices with 4 Mol/L guanidine hydrochloride (GuHCl) also improved attachment and orientation, and when undemineralized dentin was subjected to dissociative extraction, cell attachment was comparable and orientation superior to that on demineralized surfaces. These studies in dictate that demineralization is not a prerequisite for facilitating attachment, and that enhanced attachment and orientation of cells are not dependent upon a collagenous substratum. [ABSTRACT FROM AUTHOR]

Initial attachment and longer-term cell migration, attachment, and orientation of cultured human gingival fibroblasts to untreated, collagen-coated, and demineralized root slices were measured. Cells pre-labeled with 51chromium were used to measure initial attachment. Refractile material in relation to the root slices, observed using phase contrast optics and known to result from orientation of cell sheets, was measured to assess cell migration, attachment, and orientation. No significant difference in initial cell attachment of 51Cr-labeled cells to demineralized, collagen-coated, or untreated root slices was detected tip to one hr of incubation. However, after 72 hr of culture, cell attachment, migration, and orientation were significantly greater in relation to demineralized and collagen-coated root slices than to untreated root slices. Analysis of the data suggests that collagen-coating could enhance cell migration, attachment, and orientation, but not initial attachment, to surfaces that cannot be demineralized. [ABSTRACT FROM AUTHOR]