A study of epithelial odontogenic residues in the pig.

Formation of the junctional epithelium was studied by routine light microscopy in the molar teeth of commercially slaughtered pigs. It was found that the process whereby the reduced enamel epithelium (REE) contributed to the junctional epithelium formation corresponded largely with changes in man previously described by Schroeder and Listgarten (Monographs in Developmental Biology, Vol. II, Basel, S. Karger, 1971). The configuration of the marginal rests of Malassez (ROM) and their relationship to the junctional epithelium and REE was similarly studied by means of true serial sections. It was found that the ROM in that portion of the periodontium below the alveolar crest formed a well defined network of epithelial strands, but the network became more poorly defined and diverged away from the surface of the cementum as the cementoenamel junction was approached. The coronal border of this network ultimately became continuous with the REE by means of a relatively few vertical strands of epithelium. The possibility that the presence of epithelial residues in the periodontium may contribute to pocket formation and the potential effects of its configuration and continuity with the junctional epithelium are speculatively considered.