Tissue formation on cementum surfaces in vivo.

The purpose of the present investigation was to study cell colonization of and tissue formation on denuded (anorganic) cementum surfaces as well as denuded demineralized cementum surfaces. The most conspicuous finding was the distinctly different pattern of cell colonization and subsequent tissue formation on etched and non-etched denuded cementum surfaces. Non-etched cementum surfaces displayed a limited number of resorbing cells and resorption lacunae, while etched cementum surfaces displayed an abundance of fibroblast-like cells in varying stages of activity in a meshwork of fibres, probably collagenous. These fibres were organized in a layer parallel to the root surface. This appearance of a fibrous capsule-like structure has previously been associated with periodontal healing with a non-functional repair-tissue. It may be concluded, based on the present results that, a cementum surface in which collagen fibers have been exposed presents a suitable surface for colonization by mesenchymal cells. However, if collagen fibers are not exposed in the cementum surface leaving mineralized surface, mesenchymal cells appear not to be able to attach.