The distribution of fibronectin in rat tooth and periodontal tissues: an immunofluorescence study using a monoclonal antibody.

The distribution of fibronectin (FN) in longitudinal, buccolingual sections of decalcified adult rat periodontium and teeth was studied by indirect immunofluorescence using a monoclonal antibody. FN was present in virtually all regions of the periodontium, including the gingiva, periodontal ligament, many blood vessel walls, alveolar bone, incisor and molar predentine and dentine, and molar acellular and cellular cementum. The cementum of the incisor, ameloblasts, stratum intermedium and stellate reticulum, and the connective tissue of the pulp and the surface of ondontoblasts facing the pulp in the incisor and molar were not labeled for FN. FN distribution was not always uniform either within a given connective tissue or between different connective tissues of the same organ.

Specific immunohistochemical localization of type III collagen in porcine periodontal tissues using the peroxidase-antiperoxidase method.

Specific antibodies to porcine gingival type III collagen were raised in sheep. After purification on collagen affinity columns the antibodies were used for immunohistochemical localization of type III collagen in porcine periodontal and dental tissues employing the peroxidase-antiperoxidase (PAP) procedure. The extent of staining of the periodontal tissues was found to approximate the amount of type III collagen measured biochemically. A fairly uniform distribution of type III collagen was observed in the periodontal ligament and gingiva with more intense staining often being associated with blood vessels. A regular pattern of weakly staining fibers could be demonstrated throughout the cementum and in parts of the alveolar bone tissue. In addition, occasional sites in the cementum having a different morphological appearance from the rest of the cementum exhibited bundles of positively stained fibers. Although the bone tissue was essentially unstained, fibers in the endosteal spaces stained strongly. Sharpey's fibers passing from the soft connective tissues into alveolar bone and cementum also stained strongly. Three distinct arrangements of collagen fibers stained by the type III collagen antibodies could be identified: first, a reticular pattern, which was seen at the junction of the gingival epithelium and connective tissue, and in the endosteal spaces and dental pulp; second, a more diffuse pattern of fibers intermingled with type I collagen in the soft connective tissues; and third, a coating of some Sharpey's fibers, having a core believed to be type I collagen, and of fibers in the cementum inclusions.

Comparative collagen biochemistry of bovine periodontium, gingiva, and dental pulp.

Cross-linking patterns of the collagen from bovine gingiva, periodontium, and dental pulp were analyzed chromatographically. The ratios of two main cross-links, dihydroxylysinonorleucine to hydroxylysinonorlecuine, were 0.18, 0.31, and 0.49 for the bovine gingiva, periodontium, and dental pulp collagen, respectively. These ratios are similar to that of skin collagen rather than that of bone and dentin collagen.

Study of the noncollagenous components of the periodontium.

Periodontal ligament and gingivae of bovine and porcine periodontium were analyzed for relative amounts of carbohydrates, collagen, and acid mucopolysaccharides. The sugar content was 3.6% and 3.4% of dry weight in bovine and porcine periodontal ligament, respectively. The values were lower in the gingivae being 2.34% and 2.30%, respectively. Approximately 50% of hexosamine in gingivae was present in acid mucopolysacchrides as compared to 36% in periodontal ligament. Relative to collagen there was a considerable amount of non-collagenous glycoproteins present in the periodontium as judged by carbohydrate content of the tissue.

The ontogeny of substance P--containing nerve fibres in the developing mouse dentition.

The putative neurotransmitter, substance P, was localised in the developing teeth and periodontium of mice by indirect immunofluorescence. Substance P-containing fibres were visible in the incisor dental follicle eighteen days post-conception and entered the pulp two days after birth. The first molar pulp was innervated four days after birth and the second molar six days after birth. Innervation of the teeth by substance P fibres was delayed compared with the mucous and cutaneous innervation of adjacent areas and correlated with the stage of development of the teeth rather than the chronological age of the animal. The innervation of developing dental structures by substance P probably represents the establishment of a sensory supply prior to function of the tooth.

Immunoglobulins in periodontal tissues. II. Concentrations of immunoglobulins in granulation tissue from pockets of periodontosis and periodontitis patients.

In recent years evidence in the literature has indicated that the immune response may play an important role in the initiation and progression of the periodontal diseases. A study was initiated to determine the IgA, IgG, and IgM concentrations in the granulation tissue removed from deep infrabony pockets of patients with periodontosis and advanced periodontitis. Comparison of mean immunoglobulin levels between the periodontosis and periodontitis groups revealed a statistically significant increase (P less than 0.05) for IgG in the granulation tissue from the periodontosis group. The possible implications of these findings are discussed.

A longitudinal study of peridontal status comparing osseous recontouring with flap curettage. I. Results after 6 months.

The purpose this study was to test for short-term clinical differences in periodontal status after treatment with osseous recontouring and flap curettage in humans. Twelve systemically healthy patients with bilaterally similar marginal periodontal destruction received a standardized regime of presurgical therapy. The posterior segments of these patients were then treated with osseous recontouring and flap curettage. The investigators assigned the segments in one jaw at random to osseous recontouring and flap curettage, and then reversed the sides receiving surgical treatment in the opposing jaw. Postsurgical photographs and measurements for supragingival plaque, tooth mobility, gingival inflammation and periodontal attachment levels relative to the cemento-enamel junction were made for 6 months. Statistical analysis revealed that: (1) osseous recontouring and open flap curettage equally reduced plaque and gingival inflammation; (2) each surgical procedure equally increased attached gingiva; (3) pocket reduction achieved with osseous recontouring was maintained over 6 months, pockets recurring after open curettage; (4) open curettage did not induce bone regeneration; (5) osseous recontouring did not result in irreversible tooth mobility; (6) osseous recontouring resulted in a net loss of attachment; open curettage producing a net gain, especially in deeper pockets; and (7) both procedures improved periodontal health.

Site-specific variations in the biochemical composition of healthy sheep periodontium.

A topographical biochemical analysis of the periodontal soft tissues was carried out. The protein distribution in the tooth-supporting structures was determined from site by amino acid analysis and was compared with the collagen distribution in tissue protein, based upon hydroxyproline content. The biochemical composition of the periodontal ligament was heterogeneous but some specific patterns of protein and collagen distribution emerged. Protein concentration was highest at the gingival epithelium and adjacent to the cementum. Collagen concentrations were highest at the alveolar bone and below the junctional epithelium adjacent to the tooth. Such patterns may influence the way in which periodontal disease is propagated through the tissue.

Immunofluorescence localization of type I and type III collagen and fibronectin in mouse dental tissues in late development and during molar eruption.

Affinity-purified antibodies produced intense staining for type I collagen in alveolar bone matrix and predentine, and moderate staining in the dentine matrix, lamina propria, connective tissue invaginating into papillary layer of the enamel organ, dental sac and periodontal ligament. No staining occurred in oral epithelium, stellate reticulum, stratum intermedium, ameloblasts and odontoblasts. Fibronectin was distributed similarly except at the interface between the epithelial diaphragm and pre-odontoblasts where type I collagen was absent but fibronectin was present. In contrast, type III collagen showed strong staining in the periodontal ligament and lamina propria but no staining in bone matrix, predentine, dentine and at the interface between the epithelial diaphragm and pre-odontoblasts. The staining pattern for type III collagen was similar to that of type I and fibronectin in other tissues including endosteal reticular tissue, the connective tissue invaginating into papillary layer and the extracellular matrix of the pulp.

A quantitative ultrastructural study of the extracellular matrix of the sheep incisor periodontium.

The ultrastructure of the matrix of the sheep central incisor periodontium was quantitatively analysed. Ewes with healthy mouths were selected. The distribution of collagen fibril diameters was bimodal in the lower dental pad with a population standard deviation significantly larger than the unimodal distribution of fibril diameters found in the periodontal ligament. The lower dental pad connective tissue also contained significantly more oxytalan fibres, some of which resembled mature elastin. These results are consistent with the view that the sheep central incisor is supported primarily by tension within the fibres of the lower dental pad.