Immunohistochemical localization of collagenous components in healthy periodontal tissues of the rat and marmoset (Callithrix jacchus).

Abstract
The distribution of collagen types I and III was demonstrated in healthy periodontal tissues of the rat and marmoset using immunofluorescent localization after decalcification of the maxillae and mandiblae in 0.2 N HCl. An intense fluorescence in the alveolar bone and cementum matrix, as well as in the soft periodontal tissue, was demonstrated with anti-collagen type I antibodies. In the gingival connective tissue and in the periodontal ligament thick fibers of collagen type I could be observed. The fluorescent reaction in the rat periodontal ligament was not strong in comparison to the marmoset periodontal ligament. Sharpey's fibers, inserting into the cementum and alveolar bone, were also stained. On the other hand, collagen type III could not be demonstrated in the hard periodontal tissues, but could be in the bone marrow stroma and the incremental lines as well as around the Sharpey's fibers of the cementum, in accordance to previous studies. In the gingival connective tissue a strong staining was evident, especially near the basement membrane. The periodontal ligament showed an intense fluorescence that was, in some areas, continuous with Sharpey's fibers inserting into the cementum. The distribution of collagen types I and III was demonstrated with immunohistochemical techniques in the rat and marmoset periodontium. These results provide necessary information on healthy tissues that will be required for future studies on the effects of pathological, reparative and regenerative processes.