In-vitro formation of a new fibrous attachment to human dental roots in the presence of autologous serum.
Recent studies have accomplished the establishment of a collagenous fiber-fringe matrix upon dental root surfaces in vitro. The present study was undertaken to follow the development of such a matrix in vitro and to test the possible effects of root surface treatments upon this matrix. Periodontal ligament cells, 0.1 to 0.2-mm thick dental root discs, and alveolar bone cells were derived after extraction from four partially erupted third molars and the accompanying interradicular bony septa of 1 male patient. Autologous serum was obtained by venipuncture. Cultures were initiated by delivering a 1-ml suspension of 50,000 tritiated thymidine-labeled periodontal ligament cells and 50,000 alveolar bone cells onto each of 42 culture sets. The following day, demineralized or non-demineralized root discs treated with autologous serum, fibronectin or complete medium were placed in pairs, separated by a 0.1-1.0 mm gap, upon the initial cell layer. Representative cultures were terminated after 2, 3, 4, 5 and 6 weeks, and processed for light- and electron microscopy, morphometric analysis and autoradiography. An outstanding feature of the early cultures (2, 3 and 4 weeks) was a patchwise, random distribution of matrix making a precise developmental study impossible, although collagen fibrils were produced within the first 2 weeks. Some 3-week cultures already demonstrated a mature fiber-fringe characterized electron-microscopically as oriented, densely packed collagen fibrils closely abutting the cementum-lined root discs. The treatments (including autologous serum) used in this study had no appreciable morphologic or morphometric effect upon the fiber-fringe formed. Because none of the cultures in the present or past studies have demonstrated a true cementoid matrix, this model may not be suitable for the in-vitro study of cementum formation.
Bernstein
A B
AB
Department of Oral Structural Biology, University of Zürich, Switzerland.
Preisig
E
E
Pajarola
G
G
Schroeder
H E
HE
D000328:Adult; D000539:Alveolar Process / Q000166:cytology; D001345:Autoradiography; D001769:Blood; D002478:Cells, Cultured; D003094:Collagen / Q000648:ultrastructure; D003739:Dental Cementum / Q000648:ultrastructure; D003804:Dentin / Q000648:ultrastructure; D005109:Extracellular Matrix / Q000648:ultrastructure*; D006801:Humans; D008297:Male; D010513:Periodontal Ligament / Q000166:cytology; D013997:Time Factors; D014092:Tooth Root / Q000648:ultrastructure*
D003094:Collagen