bluuebunny/crossref_metadata_2025_split huggingface dataset:
Epithelial changes in gingivitis
Authors: Thilander Holger 
Published: July 2006

The changes in epithelial structure due to inflammation were studied with the electron microscope. The material comprised biopsies from inflamed gingivae in 12 adult patients. The first change noticed in the epithelium was a widening of the intercellular spaces. When the widening was of moderate degree intermediate junctions, tight junctions and desmosomes were still observed. With increased widening the intermediate junctions disappeared first, then the tight junctions and, as a subsequent change there was a reduction in the number of the desmosomes. Leucocytes of different types were often present between the epithelial cells. In some areas, the lamina densa was diffuse or completely absent. Whether this was a real breakdown or an artefact is difficult to decide. In the cytoplasm of the epithelial cells there were numerous glycogen granules and swollen mitochondria with reduced numbers of cristae.More advanced changes consisted of localised disintegration of cytoplasm and other changes of the type that precede cell death. The possible effects of these morphological changes upon epithelial permeability are discussed.
An in vitro study of anti‐calculus agents
Authors: Mukherjee S. 
Published: July 2006

A number of chemicals that could dissolve the organic part of the dental calculus or its inorganic salts were tested in vitro as possible anti‐calculus agents. Several of them were tried in combination. The effect was studied for five and ten minutes on finely meshed calculus, dentine and enamel.None of the chemicals tested, either alone or in combination with another chemical, had a selective effect on calculus. On the basis of total weight, dentine was often dissolved to a greater extent than calculus, although the percentage of total phosphorus dissolved was greatest for calculus. Organic solvents always showed a low dissolution effect. However, Ascoxal at pH 4.5–5 showed a much greater effect on calculus than on dentine and enamel.
The effect of deficiencies of calcium, vitamin D or calcium and vitamin D and of variations in the source of dietary protein on the supporting tissues of the rat molar
Authors: Oliver W. M. 
Published: July 2006

An histological investigation has been carried out on the periodontal tissues of young rats fed for eight weeks on diets deficient either in calcium (calcium content 0.026 per cent; calcium to phosphorus ratio 0.058), vitamin D, or calcium and vitamin D, in which protein was supplied either as blood albumen or egg albumen.When the diet contained blood albumen, the deficiency of calcium resulted in alveolar changes resembling osteoporosis and in a reduction in the number and diameter of the fibres of the periodontal ligament. When the diet contained blood albumen, the deficiency of calcium and vitamin D caused alveolar changes resembling osteoporosis and a reduction in the number and diameter of the fibres of the periodontal ligament. The deficiency of vitamin D had no obvious effect on the periodontal tissues of the rat. The substitution of egg albumen for the blood albumen in the diets intensified the osteoporotic changes caused by the deffciency of calcium. In rats deficient in calcium and vitamin D it superimposed an osteomalacic change, resulting in a condition of the alveolar process which resembled a combination of osteomalacia and osteoporosis. It also increased the incidence of areas of resorption of primary cementum in all dietary groups. The cementoid on the surface of secondary cementum behaved under these conditions of dietary stress in the same way as the osteoid. The manner in which the dietary deficiencies may produce these changes is discussed.
The molecular size of enzymes from dental plaque material
Authors: Söder Per‐Östen 
Published: July 2006

Amylase, proteases and hyaluronidases were separated from dental plaque material with the aid of gel filtration on Sephadex G‐100 and G‐200. The filtration values of these enzymes were compared to those of proteins of known molecular weight. Good agreement was found between the values estimated from gel filtration and the known values.The calculated values for the different enzymes in the dental plaque are:The hyaluronidase, H1 > 300.000, H2∼200.000, H3∼150.000 and H4∼100.000. The proteases, PIIa∼40.000, PIIb∼23.000 and PIIc∼18.000. The amylase∼16.000.
The primary immune response of mice to two submucosal antigens
Authors: Young W. G. , Dick H. M. , Trott J. R. 
Published: July 2006

Within the limits of these experiments there appeared to be a difference in quality of the immune response of mice to Bovine Serum Albumin and Horse Ferritin. A primary injection of Bovine Serum Albumin in the mandibular labial sulcus was followed by cell replication and plasma cell differentiation in the cervical lymph nodes and a rise in serum antibody.No similar quantitatively measurable cellular response was found in the cervical lymph nodes to a primary injection of Horse Ferritin in the same site, although detectable quantities of serum antibody were present in the same animals.
The effects of diets of different physical consistencies on the periodontal proliferative activity in young adult rats
Authors: Weiss R. , Stahl S. S. , Tonna E. A. 
Published: July 2006

Twenty young adult male rats were divided into two groups of ten rats each and fed either a powder or pellet diet of identical content for a thirty day experimental period. One hour prior to sacrifice, each rat was given an intraperitoneal injection of 0.5uc of tritiated thymidine per gram of body weight. After sacrifice, the maxillae were dissected out and prepared for autoradiographic and histologic study.Proliferative cellular activity was determined in the periodontal tissues of the maxillary first molars. Significantly higher activity was noted in the crestal epithelium and in the fibroblasts at the interradicular septum of the pellet fed rats when compared to powder fed animals. These elevated values may reflect tissue responses to the coarser consistency of the pellets.
Dietary influences on the formation of dental calculus in rats
Authors: Shannon Ira L. , Carroll Edward C. , Madsen Kenneth O. 
Published: July 2006

Eleven diets were evaluated for their ability to produce dental calculus in albino rats. A diet containing 50 % cornstarch, 32 % nonfat dry milk, 3 % liver powder, 5 % celluflour, 1 % cottonseed oil, 5 % powdered sucrose, 1 % calcium chloride dihydrate, 2.7 % sodium dihydrogen phosphate monohydrate, and 0.3 % magnesium sulfate (Francis and Briner 1969) was remarkably effective. On the basis of a 0–3 calculus scoring system, an average score of 2.36 (S.D. = 0.65) resulted after 4 weeks' exposure to the above diet and, after 8 weeks, the average score was 2.59 (S.D. = 0.56).While it was found that, in general, high cornstarch and milk powder diets were associated with higher calculus scores, no other diet remotely approached the above diet in calculogenicity.
An electron microscopic study of the regeneration of gingival epithelium following gingivectomy in the dog
Authors: Innes P.B. 
Published: July 2006

Regeneration of dog gingival epithelium following gingivectomy was studied electron microscopically. The wounds were sampled at 24 hour intervals until 14 days following the operation. From a relatively undifferentiated migrating epithelium the process of differentiation resulted in the following sequence of events. In areas where the cells made contact with the fibrin of the blood clot, a basal lamina and hemidesmosomes appeared, the number of cytofilaments increased as did the number of desmosomes and free ribosomes. Further differentiation in the masticatory epithelium was related to keratinization. The cytofilaments in the cells of the upper layers became grouped into bundles, membrane‐coating granules and keratohyalin granules appeared, the intercellular spaces in the superficial layers became narrowed and finally a stratum corneum was formed by the seventh day. In the epithelium lining the crevice a stratum corneum was not formed, the intercellular spaces in all the layers remained wide and the cells in the upper layers developed a relatively prominent Golgi apparatus and numerous membrane‐bound granules throughout their cytoplasm.The result of the differentiation in the regenerated gingiva was the formation of masticatory and crevicular epithelium which were ultrastructurally similar to the two epithelia originally present.
The influence of time of examination, eating, smoking and frequency of brushing on the oral debris index
Authors: McKendrick A.J.W. , Barbenel L.M.H. , McHugh W.D. 
Published: July 2006

The effect of time of day, eating since the teeth were last brushed, and the number of stained teeth in smokers, on the Oral Debris Index (Greene and Vermillion 1960) was examined. The effects were found to be non‐significant.Increased frequency of toothbrushing was found to produce a statistically significant reduction in oral debris.
Specific antibody in gingiva and submandibular nodes of monkeys with allergic periodontal disease
Authors: Ranney Richard R. 
Published: July 2006

Gingiva and submandibular lymph nodes from 12 squirrel monkeys that had been sensitized to ovalbumin, and from 4 unsensitized monkeys, were studied for the presence of cells containing specific antibody after intracrevicular challenge with ovalbumin‐soaked thread. Immunofluorescent methods were used to identify antibody to ovalbumin in cells in these tissues.The chronic allergic response in the gingiva of sensitized animals that had been challenged three times per week for three months did include cells containing antibody to the antigen used for sensitization and challenge. Such cells were not found in gingiva from similarly treated unsensitized monkeys, or from sensitized monkeys challenged for a shorter time.A few antibody‐containing cells were found in the submandibular lymph nodes ipsilateral to chronic intracrevicular placement of antigen in unsensitized animals, indicating active sensitization by gingival absorption of antigen. Antibody formation by cells in submandibular nodes, induced by systemic sensitization, was continued in nodes ipsilateral to gingival challenge, but tended to disappear in contralateral nodes.
Attachment of plaque and calculus to tooth surfaces
Authors: Selvig Knut A. 
Published: July 2006

The ultrastructural nature of the interface between dental hard tissue and soft and calcified deposits was studied in undecalcified and decalcified thin sections from 28 extracted human teeth. Uncalcified plaques contained clusters of densely packed microorganisms which adhered to cuticular structures or directly to the tooth surface. In calcified deposits, on the other hand, larger amounts of intercellular material generally separated the cells from each other and from the tooth surface. An intimate relationship existed in most instances between the intercellular matrix of calculus and the organic matrix of the dental hard tissue as well as between the mineral crystals of calculus and those of the underlying tooth surfaces.Mechanical locking of the deposits in cracks, resorptions, carious lesions, and other defects of the tooth surface was frequently observed. Moreover, calculus was closely adapted to the sub‐microscopic irregularities which were present even on “smooth” tooth surfaces. At the ultra‐structural level, the predominant mode of attachment appeared to be the adhesion of organic interbacterial substance to the tooth surface, in addition to intercrystalline forces of inorganic nature acting between crystals of calculus and underlying tooth substance. The relative importance of the latter factor presumably increases as the concrement matures.
Presence of leukocytes in crevices of healthy and chronically inflamed gingivae
Authors: Attström Rolf 
Published: July 2006

The presence of leukocytes within the crevices of clinically healthy and chronically inflamed gingivae has been studied in human and dog. Cellular samples were obtained from the gingival crevices by the “Styroflex” technique. The area on the styroflex film showing the presence of leukocytes was determined and a differential count of the cells performed. Biopsies were also taken from dogs with clinically healthy gingivae.Neutrophils, lymphocytes and monocytes were regularly found in samples from clinically healthy gingivae even when histological sections failed to show any inflammatory infiltrates in the gingival connective tissue. The differential counts showed 95–97 % neutrophils, 1–2 % lymphocytes and 2–3 % monocytes. Increased numbers of leukocytes were found in the crevices of chronically inflamed gingivae. However, the proportions of the various leukocytes were the same as those found in the crevices of clinically healthy gingivae. The results of the present investigation support the view that only quantitative differences exist between clinically healthy and chronically inflamed gingivae.
Periodontal conditions in patients treated with dental bridges
Authors: Silness John 
Published: July 2006

The investigation was undertaken to evaluate the effect on the periodontal conditions of fixed unilateral bridges which had been in the mouth 1 to 3 years. Seventy‐three bridges in 73 patients (50 women, 23 men) were examined. One group of 35 individuals had been instructed in methods for improving their oral hygiene, whereas another group (38 individuals) had not.In all, 146 abutment teeth were examined. An equal number of homologus teeth in the same patients served as controls. The gingival state and oral hygiene were recorded according to index systems proposed by Löe and Silness (1963) and Silness and Löe (1964). Pocket depth measurements were made as explained by Glavind and Löe (1967). The location of the crown margins of the bridge retainers was recorded according to a Margin Index System proposed by the author. The distribution of soft deposits and the location of gingivitis were similar around the abutment teeth and the homologous teeth. The average pocket depth of the abutment teeth was not deeper than that of the controls. In areas with crown margins below the gingival crest, more severe gingivitis was registered than in the control areas. The periodontal conditions were better in the individuals who had been instructed to practice oral hygiene measures as compared to the non‐instructed individuals. Possible reasons why soft deposits remain undetected on clinical examination of subgingival restorations are discussed. It is suggested that the gingival inflammation around the abutment teeth and the homologous teeth is caused by the usual bacterial mechanisms.
In vitro experiments on gingival exudate mesurements
Authors: Leirskar Jakob 
Published: July 2006

Different test solutions moved 2.5–2.9 times faster on Munktell's filter paper no. 3 than on Whatman filter paper no. 1. The paper quality may thas be an important factor when measuring gingival exudatc by the filter paper method, and results obtained with different types of paper may not be comparable.Upon descending chromatography a 30–50 per cent increase was found in mobility as compared to ascending chromatograpiiy, indicating that gingival exudate measurements may be influenced by the flow direction.
A vital microscopy morphology of study of normal the and inflamed gingiva
Authors: Hock Janet , Nuki Klaus 
Published: June 2006

Using a specially constructed microscope and transilluminating the intact free gingiva of ferrets, opossums, cats, dogs and rhesus monkeys, blood flow and vascular morphology were observed. Recordings were made on motion picture film at speeds up to 300 frames per second. The state of health of the gingiva was assessed clinically, histologically and by vital microscopy and the three assessments compared.The results indicate that free gingiva which have never been involved in inflammation exhibit a vascular morphology which can be described as a network. With the onset of histopathologic inflammatory changes, the network transforms to a characteristic loop appearance. Five stages of morphologic change are described, based upon the vascular topography seen at various stages of the cellular inflam‐ matory response.It is concluded that the vascular changes of inflammation in the free gingiva of the species studied, precede clinical and epithelial changes.
The interdental gingivae
Authors: McHugh W. D. 
Published: July 2006

Material from 20 young rhesus monkeys was prepared for study of the interdental gingival epithelium. An additional four young monkeys were injected with tritiated thymidine and radioautographs prepared for analysis of cell turnover.It was found that the interdental gingiva between recently erupted teeth in proximal contact has a col form. The appearance of the col can be simulated by vertical sections close to the roots of single teeth. Analysis of sections through the actual col showed that it is always lined by squamous epithelium, five or more cell‐layers thick, without any recognizable ameloblasts. The radioautographs showed consistent evidence of thymidine uptake, indicating cell‐division, in all epithelia lining the col. It was concluded that the histological features and turnover‐rate of epithelium in the interdental region are closely analogous to those of epithelium on other aspects of the teeth.Clinical studies of the presence and amount of plaque and gingivitis in 1,075 intact interdental areas in 48 young adults showed a high degree of correlation between the presence and amount of plaque and the presence and severity of gingivitis, and lend support to the hypothesis that gingivitis starts interdentally because plaque accumulates there.
The ultrastructure of clinically normal sulcular tissues in the beagle dog
Authors: Garant P. R. , Mulvihill J. E. 
Published: July 2006

The ultrastructure of clinically normal beagle sulcular epithelium and underlying connective tissue has been studied in order to obtain base line information for comparison with similar studies of overtly inflamed gingiva. Normal sulcular epithelium in the beagle was observed to undergo a cytodifferentiation from typical keralinocytes of the stratum basale and stratum spinosum to flattened superficial cells which contained a relatively prominent endoplasmic reticulum and Golgi system. These cells also contained many dense granules of an unknown function. Narrow intercellular spaces filled with a material of moderate electron density were observed between flattened superficial cells. Moderate numbers of neutrophils were found in the epithelium along with “clear cells” of an unknown type.The underlying connective tissue was characterized by a preponderance of well organized collagen libers and numerous fibroblasts. No unusual findings were noted in either blood vessels or peripheral nerves. Macrophages were prominently located in the lamina propria and in perivascular locations. Lymphocytes, neutrophils and plasma cells were seen in moderate numbers, usually located in the lamina propria portion of the sulcular wall. These cells when present in moderate numbers do not appreciably alter the integrity of the tissues and should be considered as components of a normal defense system.
Freeze‐etching and dental research
Authors: Newman H. N. 
Published: July 2006

Dental plaque is the aetiologie factor common to caries and chronic periodontitis. Understanding of the structure of this microbial film has been hindered by the fact that conventional methods of fixation and embedding are more or less disruptive in their effects. Freeze‐etching provides a means of examining plaque at an ultrastructural level in a state more closely approximating to that existing in vivo than is possible with other methods. The technique has been applied to the study of several oral commensal bacteria. Nocardia, Bacillus subtilis and Streptococcus viridans species have been shown to possess particulate cytoplasmic membranes, more particles being present on outer than on inner aspects. The previously described pattern of the spore coat of B. subtilis is confirmed, and, as in other non‐oral species, the organisms examined appeared to possess regularly structured cell walls. The banded appearance of S. viridans is similar to that in S. mutans recently seen using scanning electron microscopy.Similar features of cell wall and cytoplasmic membrane have been observed in samples of dental plaque. Specimens resembling outer (salivary) surface plaque as prepared for conventional electron microscopy were found to contain numerous types of organism, principally coccal, in a fairly homogeneous matrix. Many cells possessed intracytoplasmic organelles. In the deeper layers, extracellular bodies were sometimes visible in the interbacterial matrix. Several types of fibrillar component were observed, passing between adjacent bacterial membrane layers, extending from the cell wall into the plaque matrix and connecting adjoining organisms. It is suggested that such fibrillar structures may be as significant in maintaining attachment of micro‐organisms to one another and to the tooth surface as any inherent stickiness of polysaccharides. Some organisms were found to be joined to one another by broad, structureless junctional zones. Many organisms possessed intracytoplasmic inclusions and cells were frequently septate.
A histochemical study of arylaminopeptidases in hydantoin induced hyperplastic, healthy and inflamed human gingiva
Authors: Larmas L. A. , Mäkinen K. K. , Paunio K. U. 
Published: July 2006

Arylaminopeptidase activity in hydantoin induced hyperplastic, inflamed and healthy human gingiva was studied using various N‐L‐aminoacyl‐2‐naphthylamines as substrates. The activity was seen to be located in the basal cell layer of the epithelium in the entire connective tissue, but it was strongest just below the epithelium in all tissues. High enzymic activity was also observed in the inflammatory cells as well as in the capillary walls of hydantoinhyperplastic and inflamed gingiva. Strong enzymic activity was obtained when N‐L‐alanyl‐, N‐L‐methionyl‐ and N‐L‐leacyl‐2‐naphthylamine were used as substrates. Moderate activity was observed with N‐L‐arginyl‐2‐naphthylamine and N‐Llysyl‐2‐naphthylamine in other tissues except in healthy gingiva where the enzymic activity was low or nil. To test the possible involvement of aminopeptidase B in the material the reactions were performed both in the presence and absence of 0.2 M sodium chloride, which specifically activates this enzyme. There was no observable enzymic activity in any slices when N‐L‐prolyl‐2‐naphthylamine was used as substrate.The role of different arylaminopeptidases in connection with gingival hyperplasia caused by diphenylhydantoin and the evident absence of enzymes specific to N‐L‐prolyl‐2‐naphthylamine are discussed.
Studies of mast cells in the human gingiva
Authors: Angeloploulos A. P. 
Published: July 2006

The morphology of mast cells was studied in specimens from clinically normal and inflamed gingiva of 15 patients and from the tongues of two albino rats.Two types of mast cells were described, the typical and atypical. Only the typical mast cells were used to study size and shape of human gingival and rat tongue mast cells. Their shape varied considerably from spherical to ovoid and elongated. Only 7·6% of the mast cells in the human gingiva were found to be spherical, while about 70% had a lenghtlwidth ratio from 1·1 to 2·0. Their area also varied; about 80% of the gingival mast cells had an area from 20 to 100 μm2, with an average of 68·05 μm2No difference was found in the shape of mast cells between human gingiva and rat tongue, although the mast cells of the rat tongue were larger in size than those of the human gingiva.