bluuebunny/crossref_metadata_2025 huggingface dataset:
Immunosuppression and periodontal disease in man
Authors: Tollefsen T. , Strömme Koppang Hanna , Messelt E.
Published: July 2006

Gingival biopsies were taken from three main categories of patients. One group (IS) comprised 19 patients of whom 16 had received renal allografts. All were treated with immunosuppressive agents. A second group (UH) consisted of 19 patients who suffered from chronic renal failure. Control specimens were obtained from 30 systemically healthy subjects with plaque‐free teeth and healthy gingiva. Samples were also taken from 30 other systemically healthy persons with less efficient oral hygiene. Their gingival index was 1. All specimens were examined by light microscopy. In addition, eleven selected biopsies were processed for electron microscopy. Beneath the dento‐gingival epithelium the control group with plaque had a significantly higher number of cells than the other groups (p < 0.05). Residual cell infiltrates were always found in the samples from the plaque‐free healthy subjects and the uremic patients, whereas scaling and an adequate plaque control virtually eliminated inflammatory cells from the IS specimens. Lymphocytes predominated in the lesions of the UH and IS patients with clinical loss of attachment and persistent inadequate oral hygiene. It is concluded that immunosuppression does not abolish the host reaction to dental plaque, but the inflammatory and/or immune responses are different from those in otherwise healthy persons.
The routine isolation, growth, and maintenance of the intermediate‐size anaerobic oral spirochetes from periodontal pockets
Authors: Cheng Shie‐Li , Chan E. C. S.
Published: July 2006

By the combined use of membrane filters and the antibiotic rifampin, intermediate‐size anaerobic spirochetes from periodontal pockets were routinely selected and separated from other oral bacterial contaminants. Electron microscopy of six newly isolated strains showed that they belong to the genus Treponema. The organisms had generation times of about twelve hours; they produced only acetic acid when glucose was used as the carbohydrate in the medium Serum, volatile fatty acids, and thiamine pyrophosphate could be omitted individually as supplements from the growth medium, but sodium bicarbonate was absolutely essential for growth. These treponemes could be maintained by monthly transfers into fresh medium, by freezing in glycerol‐broth medium or by lyophilization.
Pulpal reactions to the application of citric acid to root‐planed dentin in beagles
Authors: Nilvéus Rolf , Selvig Knut A.
Published: July 2006

The purpose of this study was to examine histological reactions in the dental pulp incident to the application of citric acid to a root‐planed tooth surface. Full thickness flaps were raised and the labial alveolar bone removed over maxillary and mandibular incisor roots in six beagles. The exposed root surfaces were subjected to either superficial or deep root planning. On either the right or left side in each dog, citric acid (pH 1) was applied to the root surfaces for 3 min. The flaps were then repositioned at their original level. Block sections of mandibular teeth were obtained at one week and of maxillary teeth at fifteen weeks after experimental procedures. Histological examination of the short‐term specimens showed a reduced width of the predentin corresponding to the instrumented root surface, but no cellular reactions in the odontoblast layer or the pulp. At 15 weeks, varying amounts of reparative dentin had formed in all specimens. More reparative dentin had formed after deep root planing than after superficial, while the difference between acid‐conditioned and non‐acid conditioned teeth was nonsignificant. The results indicate that root planing may result in the formation of reparative dentin but does not cause inflammatory cellular reactions in the pulp. The application of citric acid to the root planed surface does not significantly change the character of the histological pulpal response.
The effect of Octapinol on dento‐gingival plaque and development of gingivitis
Authors: Willard Lars‐Olof , Edwardsson Stig , Attström Rolf , Matsson Lars
Published: July 2006

A substituted amino‐alcohol (Octapinol) with lipophilic‐hydrophilic properties and with a surface tension in water. Solution of about 40 dynes per cm and a comparatively low antibacterial effect against aerobes was tested with respect to its ability to inhibit plaque formation on extracted human molars in an Experimental Plaque System (EPS). A complete plaque inhibition was seen in the teeth treated with Octapinol during the experimental periods varying from 3 to 12 days, while a heavy plaque accumulation was seen in the control teeth during the same periods of time. In addition, Octapinol prohibited further plaque development when tested on established plaque, which also was partly disolved in the presence of the compound.

Octapinol was also tested in a short‐term study in beagle dogs and demonstrated an ability to reduce plaque formation and the development of gingivitis during an experimental period of 28 days.
Orientation of gingival fibroblasts and newly‐synthesized collagen fibers in vitro
Authors: Pitaru S. , Melcher A. H.
Published: July 2006

One hundred and fourteen pairs of transversally cut root sections ∼150 μm thick were obtained from porcine premolars and were attached to the floor of 35 mm culture dishes leaving an interdental space (IDS) of ∼500 μm between their cemental surfaces. Following partial demineralization of half of the samples, human gingival fibroblasts (HGF) were seeded in each dish and supplemented daily with 50μg/ml of vitamin C. The cultures were observed daily using phase microscopy. Demineralized and non‐demineralized specimens were obtained at each of 12 h, 24 h, 5, 10, 20, and 30 days, stained with van Gieson's picro‐fuchsin for identification of collagen or processed for examination by scanning electron microscopy (SEM). Two of the 30‐day‐old cultures were processed for examination by transmission electron microscopy.

Sheets of oriented cells anchored to the cemental surfaces of the root sections and the floor of the dish were evident at 5 days. After 10 days of culture, a multilayered bridge‐like structure of oriented cells and fibrils (50–100 nm thick) was seen to connect the opposing cemental surfaces bordering the IDS at one or more sites. Oriented fine fibrillar structures were observed at this time using van Gieson's staining. The IDS was completely filled with oriented cells and fibers after 20 days of culture. Similar structures extending between the cemental surfaces and the floor of the dish developed around the rest of the circumference of the root sections. The appearance of this material at 30 days as observed by van Gieson's staining was reminiscent of transseptal and dento‐gingival fibers in vivo. The staining by van Gieson's method, the size of the fibrils, and the banded fibrils observed by TEM in cultures 30 days old suggest that the fibrillar material was predominantly collagen.

The system was significantly more reproducible when demineralized rather than mineralized sections of root were used. It is suggested that attachment, migration, and contraction of the HGF are crucial for the orientation of the cellular and endogeneously produced fibrillar components in vitro and that these processes may operate in the development and healing of oriented fiber systems in vivo. Further, partial demineralization may facilitate these processes in wound healing.
Spontaneous lymphocyte proliferation and the periodontal status of young adults
Authors: Tew J. G. , Burmeister J. A. , Palcanis K. G. , Ranney R. R.
Published: July 2006

The objective of this study was to determine if the level of incorporation of 3H‐thymidine in unstimulated cultures of peripheral blood lymphocytes obtained from young adults differs as a function of their periodontal status. Kinetic studies using normal PBL indicated that the rate of 3H‐thymidine uptake in unstimulated cultures began to increase markedly by day 5 of culture, peaked about day 7, and then declined. When this spontaneous lymphocyte proliferative response in young adults with a healthy periodontium (HP) was compared with the response obtained from young adults with severe periodontitis (SP) and individuals with juvenile periodontitis (JP), it was observed that responses in the SP group were markedly depressed at day 5 and day 7. In contrast, responses in the JP group were nearly identical to the HP controls. Periodontal treatment of the SP group appeared to restore normal responsiveness. We believe the most likely bases for these responses to be autologous mixed lymphocyte culture reactions. The suppression of the spontaneous response in the untreated SP group may reflect changes in regulatory T‐cell function induced by a state of active disease.
T cell responses of periodontal disease patients and healthy subjects to oral microorganisms
Authors: Stashenko P. , Resmini L. M. , Haffajee A. D. , Socransky S. S.
Published: July 2006

The relationship between T cell proliferative responses to oral microorganisms and periodontal disease status was studied utilizing a standardized T cell/monocyte mixture previously shown to generate maximal proliferative responses in vitro. T cells from periodontally healthy and diseased subjects were found to respond equally well to all oral microorganisms tested. When subjects were grouped according to their T cell response profile by cluster analysis, a generalized high responder and generalized low responder group was defined. Low responders were found to have significantly more redness and bleeding on probing than high responders. No differences were found between the two groups with respect to suppuration, plaque, attachment level, pocket depth, or bone loss. Patients not falling into the high or low responder groups had intermediate proliferative responses and moderate amounts of inflammation. These findings indicate that T cell proliferative responses to oral microorganisms may identify subgroups of individuals with unique clinical features.
Observation of fimbriae and flagella in dispersed subgingival dental plaque and fresh bacterial isolates from periodontal disease
Authors: Scannapieco Frank A. , Kornman Kenneth S. , Coykendall Alan L.
Published: July 2006

The interbacterial matrix of subgingival plaque obtained from 12 individuals was examined by agar‐filtration negative stain electron microscopy. Flagellated bacteria were abundant in all samples from patients having periodontal disease. In addition, the plaques of all patients having periodontal disease, with the exception of two children diagnosed as having localized severe periodontitis, had varying amounts of long thin filamentous extracellular bacterial appendages morphologically identical to bacterial fimbriae. These appendages seemed to form into bundles to which bacterial membranes, blebs, and debris appeared to attach. Further studies examined the cell surface structures of bacteria freshly isolated from several of these plaque samples. Of 113 bacterial colonies examined, 49 (43.3%) had surface fimbriae like appendages. Actinobacillus actinomycetemcomitans, Bacteroides gracilis, Actinomyces odontolyticus, Capnocytophaga species, Fusobacteria species, and Haemophilus species had fimbriae. Only 4 of 113 colonies bore flagella. It was concluded that bacterial extracellular appendages resembling fimbriae are common morphologie components of plaque interbacterial matrix and may pay play a significant role in adhesive interactions within plaque. Although flagellated bacteria were commonly seen within subgingival plaques, few fresh isolates were observed to produce these structures.
Gingival crevicular fluid antibody to oral microorganisms
Authors: Ebersole Jeffrey L. , Taubman Martin A. , Smith Daniel J. , Max Goodson J.
Published: July 2006

A rapid method for collection of static crevicular fluid (SCF) on filter papers is described. Standardization of a Periotron® for volume quantitation of the SCF allowed accurate collection of crevicular fluid samples from periodontal disease patients. A method for elution of SCF was developed and was shown to provide nearly total recovery of antibody activity from the filter papers. Analysis of specific antibody to suspected periodontal pathogens in eight individuals indicated a site‐to‐site variation in antibody levels within the oral cavity. Also, SCF from certain sites exhibited antibody levels that were significantly greater than serum, supporting the concept of specific local antibody synthesis in gingival tissues.
Effects of phosphoric acid on root dentin surface
Authors: Héaritier M.
Published: July 2006

Roots of freshly extracted human teeth, planed up to the dentin in order to remove the cementum, were treated with a 50% solution of phosphoric acid (pH 1.3) for 1, 2, and 3 minutes. Specimens were processed for scanning (SEM) and transmission (TEM) electron microscopy. The acid application for 1 min resulted in the exposure of collagen fibrils emerging from a 4.5 μm wide demineralized layer which covered the surface of the treated root; with increasing time of etching, this layer widened and its typical collagen structure disappeared. It was concluded that a 60 s application of phosphoric acid on root dentin in vitro created the conditions which could be exploited in vivo to facilitate the reattachment (or new attachment) of healing connective tissues on root surface.
Metabolic change in cultured gingival fibroblasts exposed to bacterial extracts
Authors: Larjava Hannu
Published: July 2006

Hyaluronic acid synthesis was studied in human gingival fibroblast cultures exposed to bacterial extracts from dental plaque, Bacillus cereus, and Escherichia coli (lipopolysaccharide, LPS). Dental plaque extract was the best stimulant of hyaluronic acid synthesis. B. cereus extract was almost as effective, but the effect of LPS was insubstantial. This indicates that gram‐positive microorganisms of dental plaque, as well as gram‐negative bacteria, may be involved in the stimulation of hyaluronic acid synthesis in gingival fibroblasts.

The effect of indomethacin, cortisol, and cycloheximide on hyaluronic acid synthesis were studied in control and plaque extract treated cultures. Indomethacin had no effect whereas cortisol inhibited the synthesis both in control and treated cultures. Cycloheximide prevented the stimulation of hyaluronic acid synthesis in treated cultures. This suggests that protein synthesis is required for the stimulation of hyaluronic acid synthesis in the presence of plaque extract. The altered metabolism of connective tissue cells due to dental plaque may be important in the development of periodontal disease.
Transport pathway and uptake of microperoxidase in the junctional epithelium of healthy rat gingiva
Authors: Tanaka Teruo
Published: July 2006

Junctional epithelial uptake and transport of microperoxidase (MP, heme‐undecapeptide) was investigated in the healthy gingivae of 24–26 day old rats. MP products were observed from the blood vessels in the junctional epithelium to the internal basement lamina (IBL) close to enamel surface via the intercellular spaces of junctional epithelial (JE) cells. The IBL was strongly stained with MP, but there was an abrupt stoppage of MP at the external basement lamina (EBL). The EBL seemed to act as a barrier against transport of MP from the gingival connective tissue into the junctional epithelium. MP was also found in the micropinocytotic vesicles and phagocytotic vacuoles of innermost JE cells. Neutrophils located in the intercellular spaces of JE cells showed positive reaction for both MP and/or endogenous peroxidase. These results suggest that gingival fluid is probably transuded from the blood vessels into the junctional epithelium, reaches the IBL via the intercellular spaces, and diffuses into the oral environment along the IBL, and that toxic and foreign materials are taken up by the micropinocytotic vesicles and phagocytotic vacuoles of JE cells and the neutrophils on their way to the oral environment.
Juvenile periodontitis – no linkage with HLA‐antigens
Authors: Saxén Leena , Koskimigs Saija
Published: July 2006

Juvenile periodontitis is a severe though relatively rare inflammatory periodontal disorder of young individuals. Its etiopathogenesis is not known, but an altered immune response has been suggested. Strong indications for an autosomal recessive mode of inheritance of the disease has been shown. As full penetrance excludes association to histocompatibility antigens, the possibility of linkage to the HLA antigens was Studied. Three families, each with 2 siblings expressing juvenile periodontitis, were tissue‐typed for HLA A, B, and C locus antigens and 2 families for Dr locus by using the standard two‐stage microcytotoxicity test. It was concluded that it is very unlikely that there would be a linkage between the juvenile periodontitis gene and the HLA antigens.
Film‐holder device for radiographic assessment of periodontal tissues
Authors: Nery E. B. , Olson J. W. , Henkin J. M. , Kalbfleisch J. H.
Published: July 2006

A method, combining the standardization of radiographs with consistent radiopaque marker placement using a controlled force, is presented. Ten adult volunteers with healthy mouths were selected. Customized radiographic film holders were fabricated consisting of a plastic stent of the maxillary or mandibular arches to which a radiographic bite‐block was attached. An orthodontic stainless steel tube was added and placed so that the radiographic marker could be guided repeatedly to the base of the sulcus in the same position. The radiographs were exposed using a self‐adhesive grid on the periapical film. To document repeatability, measurements using the device were obtained at different time intervals: twice‐a‐week for the first, third, and fifth week for a total of six measurements for each volunteer. Results showed that the mean vertical and horizontal dimensions were nearly constant across the study period. The device had been shown to be accurate and enabled placement of a radiographic marker to repeatedly reach the same position in the sulcus with a good degree of precision.
Distribution and ultrastructure of subgingival plaque in beagle dogs with gingival inflammation
Authors: Theilade Jørgen , Attström Rolf
Published: July 2006

The present study was designed to describe the distribution and ultrastructure of subgingival plaque in beagle dogs in an attempt to establish a correlation between these deposits and some aspects of the adjacent soft tissue destruction. Biopsies comprising one premolar with adjacent buccal gingiva were obtained from six beagle dogs approximately two years old with clinically diagnosed chronic gingivitis. After prefixation and decalcification the biopsies were cut axially to yield 0.5 mm thick slices, after which the tissue was postfixed and embedded in Epon. From each dog one slice was randomly selected for the study. Each block was semi‐serially sectioned to provide axial sections. From the blocks of five dogs one semithin section for light microscopy and an adjacent thin section were obtained for every 50 μm in mesiodistal direction. From one dog only semithin sections for light microscopy was cut, and a section retrieved for each 10 μm interval. Light microscopy revealed that in three of the biopsies examined no subgingival plaque colonies were present on the tooth. In three biopsies, varying numbers of subgingival plaque colonies were present. Electron microscopy revealed that in one of the biopsies Gram‐negative cocci or rods predominated in all subgingival colonies observed. In the other biopsy in which subgingival colonies were present, spirochetes predominated. In all five biopsies examined in the electron microscope a few single bacteria or small groups of microorganisms were observed either between the tooth and the junctional epithelium or between the most superficial cells of the latter. Evidence of phagocytosis of microorganisms was seen, but to a limited extent. Single organisms were regularly encountered adjacent to the tooth surface in the region between the most apically established plaque colony and the first intact hemidesmosome. The distance from the gingival margin to the most apical subgingival plaque averaged 0.25 mm (S.D. ± 0.05 mm). The distance from the gingival margin to the most coronal hemidesmosome was 0.43 mm (S.D. + 0.06 mm), and this distance did not seem to be influenced by the presence or absence of subgingival plaque colonies in the section or in the biopsy slice.
Phospholipase A activity of extracellular products from Bacteroides melaninogenicus on epithelium tissue cultures
Authors: Bulkacz Jaime , Schuster George S. , Singh Baldev , Scott David F.
Published: July 2006

Seven‐day‐old cultures of epithelial outgrowths from hamster cheek pouch were incubated with 3H‐arachidonic acid for 24 hours and then subjected for 60 and 90 minutes to partially purified preparations of phospholipase A obtained from a strain of Bacteroides melaninogenicus subspecies melaninogenicus and from a strain of the subspecies intermedius, both isolated from periodontal pockets. In the cultures incubated with enzyme there was a significant release of radiolabel into the medium. A lipid analysis of the tissue cultures indicated that incubation with the enzymes produced a loss of the cells' phosphatidyl choline and phosphatidyl ethanolamine and a concomitant release of free fatty acids. These results describe for the first time a possible mechanism for epithelial cell injury mediated by an extracellular product of bacteria from the periodontal environment with phospholipase A activity.
Morphological studies on periodontal disease in the cynomolgus monkey
Authors: Brecx M. C. , Nalbandian J. , Ooya K. , Kornman K. S. , Robertson P. B.
Published: July 2006

Histological observations were made on ligature‐induced periodontitis in two adult female monkeys (Macaca fascicularis). Silk ligatures were placed around posterior teeth and the shift from gingivitis to periodontitis was followed radiographically and bacteriologically for eight and nine weeks, respectively. Fifteen tissue blocks with ligatures in situ were obtained. Following decalcification with EDTA and epon embedding, sections one micron in thickness were prepared in the mesio‐distal plane to study the interproximal regions. Two additional blocks were processed for routine histology.

Radiographically, progressive bone loss was observed in the interproximal regions that had a ligated tooth surface. Histologically, prominent features included supragingival and subgingival plaque (with dense accumulations of bacteria around and within the ligature), apical migration of the junctional epithelium, loss of collagen and connective tissue attachment, and osteoclastic bone resorption. A chronic inflammatory reaction was evidenced by a dense infiltration of leukocytes in the connective tissue, with a high proportion of plasma cells. Numerous polymorphonuclear leukocytes were seen in pathways between epithelial cells and in a zone around the plaque‐laden ligature. These morphological observations, similar to descriptions of human periodontitis, lend support for the usefulness of this model in the study of human periodontitis.
Connective tissue attachment formation following exclusion of gingival connective tissue and epithelium during healing
Authors: Magnusson Ingvar , Nyman Sture , Karring Thorkild , Egelberg Jan
Published: July 2006

The present investigation was designed to evaluate the potential for reformation of connective tissue attachment on exposed and planed root surfaces by preventing the dentogingival epithelium and the gingival connective tissue from interfering with healing following periodontal surgery.

Following the elevation of soft tissue flaps, the buccal and proximal alveolar bone of 24 teeth (48 roots) was removed to mid‐root level in 6 monkeys and the exposed root surfaces were carefully planed in order to remove the root cementum. Before the flaps were repositioned and sutured, a membrane (Millipore® filter) was placed over the denuded part of the root surfaces of 16 teeth (test teeth) in order to prevent the epithelium and the gingival connective tissue from interfering with healing. The membrane was adjusted to cover the tooth surfaces from midcrown level to approximately l mm apical to the bone crest. No membranes were placed around the remaining 8 teeth (control teeth) before flap repositioning. The animals were sacrificed 6 months after surgery. The jaws were removed and histological sections of test and control teeth including their buccal periodontal tissues were produced. Nine of the test teeth had to be excluded from examination due to technical failures in the surgical procedure or tissue preparation.

New cementum with inserting collagen fibers was observed on all remaining 14 test roots. The length of this newly formed fibrous attachment corresponded to approximately 50% of the distance from the apical extension of root planing to the cemento‐enamel junction. In the majority of the control teeth no new attachment had formed but a “long” junctional epithelium was lining the root surfaces to the apical extension of root planing. In 3 control roots a small amount of new cementum with inserting collagen fibers was found in the most apical area of root planing.

The results showed that the reformation of a connective tissue attachment was considerably favored by the placement of membranes which prevented the dentogingival epithelium and the gingival connective tissue from interfering with healing.
The effectiveness of a fluoride varnish and a desensitizing toothpaste in treating dentinal hypersensitivity
Authors: Clark D. C. , Hanley J. A. , Geoghegan S. , Vinet D.
Published: July 2006

A desensitizing toothpaste (Sensodyne) alone and toothpaste and a fluoride varnish (Duraphat) together were tested in a controlled clinical trial to determine their effectiveness in treating dentinal hypersensitivity. Twenty‐one patients were allocated into either a Control, Toothpaste‐Only, or a Toothpaste‐Varnish Group. After one month or the final treatment session, the Control Group demonstrated a 28 percent reduction in the mean group pain score, the Toothpaste‐Only Group a 2 percent reduction, and the Toothpaste‐Varnish Group a 70 percent reduction. These data indicate that professionally applied treatments with the fluoride varnish and the home use of the desensitizing toothpaste with strontium chloride are more effective than using a toothpaste alone for treating hypersensitive teeth.
Gingival crevicular fluid antibody to oral microorganisms
Authors: Ebersole J. L. , Taubman M. A. , Smith D. J.
Published: July 2006

The level and distribution of static crevicular fluid (SCF) antibody was studied in periodontal disease patients. Elevated levels of SCF antibody were demonstrated in approximately 9% of 1292 sites. The elevated responses were shown to be limited to particular bacterial specificities at any one site. Additional comparisons indicated that the frequency of elevated antibody levels in SCF were most closely related with responses to A. actinomycetemcomitans, B. gingivalis, and B. intermedius rather than clinical categorization.
Disturbances in bone remodeling during the progress of hamster periodontitis
Authors: Makris G. P. , Saffar J. L.
Published: July 2006

This study was undertaken to follow the changes in bone remodeling during the progress of periodontitis in the hamster. The comparison of quantitative and morphological data showed that the disease is associated with an important disturbance of the remodeling process. The development of bone resorption. preceded by the arrest of the physiological bone formation, is associated with an increase in the extent in reversal (=empty) lacunae. Bone formation refilled only a small number of these lacunae, although in some cases the formation reaction could be vigorous. These events coexisted and reoccurred with marked variations in space and in time, regardless of the time of exposure to the disease. Moreover, the onset at the bone level of the disease was characterized by an initial and precocious increase in bone volume, immediately subjacent to the inflammed gingival tissues.
Gas‐liquid chromatography of the gingival fluid as an aid in periodontal diagnosis
Authors: Botta G. A. , Radin L. , Costa A. , Schito G. , Blasi G.
Published: July 2006

There is increasing evidence that rod‐shaped Gram negative anaerobic bacteria, as those belonging to black‐pigmented Bacteroides, may play a role in the pathogenesis of periodontal diseases. Anaerobic bacteria are known to produce, as end‐products of their metabolism, several volatile fatty acids, whose detection in clinical specimens by direct gas liquid chromatography (GLC) has been usefully utilized to demonstrate their presence in the infected site. The results obtained analyzing by GLC the gingival fluid collected from patients suffering from periodontal diseases are reported here. A good statistical correlation of the GLC profile has been found with the gingival index and the colonization by gram‐negative bacteria at each selected site.

The data obtained strongly suggest that butyric acid may be considered a reliable marker of the severity of the disease, and its quantitative changes may be useful in following the clinical course of the process. The data correlate well with the biological activities of butyric acid, which have been reported to be abundant in plaque and to exert a cytotoxic activity on a variety of cells including gingival fibroblasts.

No correlation has been found between gingival fluid flow rate and fatty acids profile in GLC. It can be concluded that GLC measures the overall metabolic activity of the bacterial population colonizing the subgingival area, while the rate of gingival fluid flow reflects the degree of the inflammatory response of the host. The combined use of the two laboratory tests should provide the clinician with more quantitative and reproducible parameters for monitoring the disease activity.
Distinct categories of microbial forms associated with periodontal disease
Authors: Wolff L. F. , Pihlstrom B. L. , Liljemark W. F. , Schaffer E. M. , Bandt C. L.
Published: July 2006

The purpose of this study was to determine if a classification of subgingival plaque into distinct categories of microbial forms would be beneficial for detecting differences in the severity of periodontal disease. Three thousand and thirty‐two subgingival plaque samples were collected and evaluated from three different populations having 284, 160, and 180 individuals. Plaque and gingival indices, probing depth, and attachment level were measured at each sampling site. Overall, the results indicated that mean plaque index, probing depth, and loss of attachment were successively higher at sites classified into four distinct microbial categories in the order (1) “Low Motile Organism ‐ High Cocci,” (2) “Low Motile Organism ‐ Low Cocci.” (3) “High Motile Organism ‐ High Motile Rods,” and (4) “High Motile Organism ‐ High Spirochetes.” The consistent pattern of differences in severity of periodontal disease between these microbial categories suggest that microscopic interpretation of plaque may be improved by this classification.
Abnormalities of leukocyte chemotaxis in patients with various forms of periodontitis
Authors: Altman L. C. , Page R. C. , Vandesteen G. E. , Dixon L. I. , Bradford C.
Published: July 2006

Prior studies have documented that a majority of patients with juvenile periodontitis have suppressed polymorphonuclear leukocyte (PMN) chemotaxis. However, in other forms of earlyonset periodontitis, PMN migration has been studied only to a limited extent or not at all, and monocyte (MN) chemotaxis has not been extensively studied in patients with any of the forms of periodontitis. Accordingly, PMN and MN chemotaxis was studied in 7 patients with prepubertal, 37 with juvenile, and 35 with rapidly progressive periodontitis. In addition, PMN chemotaxis was studied in 8 patients with adult periodontitis. In the prepubertal group, 5 patients had abnormal PMN chemotaxis, 5 had depressed MN chemotaxis, and one had reduced serum chemotactic activity. All patients in this group had at least one form of leukocyte chemotaxis abnormality. In the juvenile periodontitis group, 17 patients had abnormal PMN responses, 16 of these were depressed while 1 was enhanced. MN chemotaxis was depressed in 4 of these patients and elevated in 2. Five patients had reduced serum chemotactic activity and one manifested a serum chemotactic inhibitor. In total, 65% of juvenile patients had some form of abnormality. In the rapidly progressive group, 15 had abnormal PMN chemotaxis, 7 had aberrant MN chemotaxis, 4 had reduced serum chemotactic activity, and 8 had a serum inhibitor of chemotaxis. No abnormalities were found in the PMNs or sera of patients with adult periodontitis. Overall, 66% of the early‐onset patients manifested some form of cell or serum‐related leukocyte chemotactic abnormality. Thus, abnormalities of leukocyte chemotaxis were present in all patients with prepubertal periodontitis and in a majority of those with juvenile and rapidly progressive disease, while no abnormalities were found in 8 patients with adult periodontitis.
Serum antibodies in young adult humans reactive with periodontitis associated treponemes
Authors: Tew J. G. , Smibert R. M. , Scott E. A. , Burmeister J. A. , Ranney R. R.
Published: July 2006

The present study was undertaken to determine whether young adults with generalized severe periodontitis (SP) or the more localized juvenile periodontitis (JP) have serum antibody reactive with a panel of periodontitis associated treponemes more frequently or at higher titer than a group of young adults with a healthy periodontium (HP). The human subjects consisted of 52 SPs, 47 JPs, and 52 HPs. The panel of treponemes included three strains of Treponema denticola and several strains of newly described treponemes, Treponema socranskii ss. socranskii, Treponema socranskii ss. buccale, and Treponema socranskii ss. paredis. The frequency and magnitude of serum antibody titers were determined using a sensitive radioimmunoassay. Subjects with JP were more frequently seropositive than were HP subjects to several strains of the treponemes tested (p<0.01 for Treponema socranskii ss. buccale [D40PE2], Treponema denticola [D3A9], and Treponema socranskii ss. paredis [D28C3]). However, the most surprising result was the low level and frequent lack of antibody in SP sera reactive with these periodontitis‐associated treponemes. Excluding data where only two points above the cut off were required for seropositivity, neither the frequency of seropositivity nor the magnitude of antibody titers of SP subjects exceeded those respective values for HP subjects. The frequency of seropositivity in SP subjects to T. socranskii ss. socranskii (D43BR1) was significantly depressed as compared to HP subjects (p<0.01). In short, it appeared that SP subjects either failed to mount a significant anti‐treponemal antibody response or those responses were specifically suppressed.
Cytochemical identification of lysosomal system of the rat junctional epithelium
Authors: Yamasaki Akira , Nikai Hiromasa , Ijuhin Naokuni , Takata Takashi , Ito Hiroshi
Published: July 2006

Structures taking part in the lysosomal system of rat junctional epithelium (JE) were evaluated by means of ultrastructural enzyme cytochemistry. Acid phosphatase (AcPase) and trimetaphosphatase (TMPase), both the representative lysosomal marker enzymes, were frequently detected in dense bodies which contained the homogeneous matrix and showed pleomorphic appearance. These activities were also often localized to the phagosomes with heterogeneous contents, the reaction of TMPase being much more intense than that of AcPase. Cisternal structures, most probably corresponding to GERL, also displayed AcPase activity and exhibited the close morphologic relationships with lysosomal structures. On the other hand, the localization of thiamine pyrophosphatase activity was almost limited to the innermost cisterna of the Golgi complex. Neither AcPase nor TMPase activity could be detected in the cytoplasmic vacuoles, which were characteristically numerous in rat JE and the multivesicular bodies.

From the present findings, it is suggested that the lysosomal system in rat JE is composed of dense bodies (primary lysosomes), phagolysosomes (secondary lysosomes), and GERL and that some of those lysosomes are apparently derived from GERL. Different localization patterns of marker enzymes examined might reflect the enzymatic heterogeneity of various lysosomal elements.
Subtraction radiography and computer assisted densitometric analyses of standardized radiographs
Authors: Ortman L. F. , Dunford R. , McHenry K. , Hausmann E.
Published: July 2006

A standardized radiographic series of incrementally increasing alveolar crestal defects in skulls were subjected to analyses by subtraction radiography and computer assisted quantitative densitometric analysis. Subjects were able to detect change using subtraction radiography in alveolar bone defects with bone loss in the range of 1–5 percent as measured by 125I absorptiometry. Quantitative densitometric analyses utilizing radiographic pairs adjusted for differences in contrast (gamma corrected) can be used to follow longitudinal changes at a particular alveolar bone site. Such measurements correlate with change observed by 125I absorptiometry (r= 0.82–0.94).
Gingival blood flow measured with a laser Doppler flowmeter
Authors: Baab David A. , ÖBerg P. Ake , Holloway G. Allen
Published: July 2006

Previous studies of gingival blood flow have used techniques that were discrete, invasive, or only applicable to animals. The present study assessed this parameter in 10 healthy humans using a noninvasive laser Doppler flowmeter (LDF), Blood flow rate was determined in the interdental papillae. Free and attached gingival, and alveolar mucosa, Measurements were made continoulsy at four sites per patient and discontinoulsy at 21 sites per arch representing the four locations. The effects of heat, cold, pressure, and occlusal force on blood flow were measured.

Blood flow wave patterns differed consistently by tissue type, Mean blood flow was singnifiantly hinger (p < 0.001) in alveolar mucosa than in the gingival. Both heat and cold produced initial hyperemia, followed by a rapid return toward baseline. Localized pressure caused ischemia followed by reactive hyperemia in all tissue types, Transient ischemia was seen during occlusal force at the free gingival margin of test teeth, but blood flow in adjacent interdental papillae and attached gingival remained unaltered. A significant difference (p < 0.001). The LDF offeres promise as a noninvasive method to study gingival blood flow.
The use of crevicular fluid prostaglandin E2 levels as a predictor of periodontal attachment loss
Authors: Offenbaceer S. , Odle B. M. , van Dyke T. E.
Published: July 2006

Longitudinal data were collected over a period of at least 18 months and up to 3 years on 41 adult periodontitis patients (AAP Type III and IV). Ramfjord attachment level measurements and sampling of crevicular fluid (CF) at each tooth were repeated every 3 months. A mean full mouth CF prostaglandin E2 (MCF‐PGE) value was determined for each patient at each visit. The three‐month monitoring was continued until a single site demonstrated a statistically and clinically significant attachment loss (ALOSS) episode. Results indicated that in ALOSS patients the MCF‐PGE was significantly elevated at the ALOSS visit as compared to previous levels. Furthermore, the sites which had the ALOSS had elevated levels as compared to the contralateral no ALOSS control sites (305.6±56.5 vs. 65.7±6.89 ng/ml, mean ± SEM). One month following treatment the CF‐PGE level dropped to 16.9±3.4 ng/ml at the ALOSS sites. Since the MCF‐PGE level increases preceding the attachment loss episode, reaches a maximum at the sites which actually undergo ALOSS, and subsides following treatment, the possibility of using the MCF‐PGE level to predict an oncoming future ALOSS episode was examined. The ALOSS patients had a MCF‐PGE level of 113.4±9.0 ng/ml 6 months prior to the ALOSS episode, which was significantly higher than the no ALOSS patients’MCF‐PGE level of 50.1±7.1. Analysis of MCF‐PGE levels as a screening test indicate that this measurement has a high degree of sensitivity, specificity, and a predictive value of 0.92–0.95. Thus, this method has significant merit as a diagnostic tool to determine if a patient is in a state of remission or about to undergo an attachment loss episode.
In situ characterization of mononuclear cells in human chronic marginal periodontitis using monoclonal antibodies
Authors: Johannessen A. C. , Nilsen R. , Knudsen G. E. , Kristopfersen T.
Published: July 2006

Acetone fixed cryostat sections from 25 patients with adult chronic marginal periodontitis were characterized using an indirect immunofluorescence technique with monoclonal antibodies. The amount of B lymphocytes (Leu‐12 positive) varied considerably between the specimens and were usually seen in largest numbers in the most apical parts of the cellular infiltrates beneath the pocket epithelium (PE). Varying amounts of T lymphocytes (OKT 3 positive) were demonstrated in all specimens. The amount of T helper cells (OKT 4a positive) exceeded that of T suppressor/cytotoxic cells (OKT 8 positive) in the cellular infiltrates beneath the PE (OKT 4a/ OKT 8 =1.13). There was a more even distribution of these cell types beneath the oral gingival epithelium (OGE). Langerhans cells were observed within and occasionally subjacent to the OGE. Scattered macrophages (Leu‐M3 or OK Ia 1 positive) were observed in the inflammatory cell infiltrates and on the connective tissue papillae beneath the OGE. HLA‐DR antigen reacting with OK Ia 1 was present on cells corresponding to OKT 6 positive cells in the OGE and subjacent to the OGE as well as in the inflammatory cell infiltrates beneath the PE and in the perivascular infiltrates. In some specimens HLA‐DR antigen was also found to be associated with keratinocytes in the outer parts of the OGE. Occasional NK cells (Leu‐7 positive) were localized inside and subjacent to the OGE. There was a considerable variation with respect to the number and distribution of the various mononuclear cells between specimens and from section to section from the same specimen.
Morphological studies on periodontal disease in the cynomolgus monkey
Authors: Brecx M. C. , Nalbandian J. , Kornman K. S. , Robertson P. B.
Published: July 2006

Electron microscopic observations were made on naturally occurring gingivitis, on gingivitis at non‐ligated sites of an experimental animal, and on ligature‐induced periodontitis in a periodontal disease model using female cynomolgus monkeys.

For both types of gingivitis specimens, a plaque associated chronic inflammatory reaction was observed, comparable to that described for the human established lesion. Bacterial accumulations on tooth surfaces were separated from the epithelium by neutrophils which exhibited variations in fine structure and extent of bacterial phagocytosis related to their proximity to the plaque. In the inflamed connective tissue of the papillae, collagen was reduced to strands extending between the cellular elements. The plasma cell was the most common inflammatory cell and had three major variations in form.

With ligature‐induced periodontitis, similar inflammatory features were observed in the gingiva. A complex flora like that encountered in human periodontitis was observed around and within the ligature as well as more apically in the pocket. As compared to the flora in gingivitis, more spirochetes were encountered, a larger proportion of the microorganisms appeared to be in a living state, and bacteria were in contact with the epithelial surface, rather than being walled off by the neutrophils. This seemingly more aggressive plaque was associated with an advanced lesion characterized by changes that indicated sequential destruction of the collagenous attachment to cementum and concommitant apical migration of the epithelial attachment. No bacteria were observed in the soft tissues, even in the wide intercellular spaces between the epithelial cells.
A biochemical approach to periodontal regeneration: Tetracycline treatment of dentin promotes fibroblast adhesion and growth
Authors: Terranova Victor P. , Franzetti Louis C. , Hic Susanne , Diflorio Roberta M. , Lyall Raymond M. , Wikesjö Ulf M. E. , Baker Pamela J. , Christersson Lars A. , Genco Robert J.
Published: July 2006

One objective of periodontal therapy after resolution of the infectious process is to facilitate a new connective tissue attachment to the root dentin surface. Here we report that a selective advantage for attachment and growth can be conferred on human gingival fibroblasts by biochemical manipulation of the dentin surface. Tetracycline HCL treatment of the dentin surface increases binding of fibronectin. The adsorbed fibronectin stimulates fibroblast attachment and growth, while suppressing epithelial cell attachment and growth. This biochemical manipulation may provide a useful approach for the treatment of periodontally involved teeth.
The effect on the composition of subgingival plaque of a simplified oral hygiene system including pulsating jet subgingival irrigation
Authors: Roy Macaulay W. J. , Newman H. N.
Published: July 2006

The aim of this study was to investigate the effect on subgingival plaque of a simplified oral hygiene regime consisting of instruction in Bass brushing without stress on interdental cleaning, scaling and root planing, in combination with subgingival pulsated jet irrigation with dilute solutions of chlorhexidine, metronidazole or placebos. Twenty‐five patients, 14 women and 11 men, each with periodontal pockets ≥ 4 mm, participated in a randomized, double‐blind, placebo‐controlled study. The patients were assigned to 4 groups: 2 test groups (0.02% chlorhexidine and 0.05% metronidazole) and 2 placebo groups (0.01% quinine sulphate and 0.09% sodium chloride). Subgingival plaque samples were obtained from at least 4 sites in each subject on days 0 (prior to scaling and root planing), 7, 28, 56 and 84. Subgingival irrigation was terminated on d 28. Darkfield microscopy was used to assess the effects of treatment on the subgingival microflora by observing 4 morphologic groups: cocci, motile organisms, spirochetes and others (i.e. non‐motile rods and filaments). All the groups showed marked beneficial changes at the end of the 28‐d irrigation period, with increases in cocci and decreases in motile forms and spirochetes to less than baseline values. These beneficial effects were maintained for at least 8 weeks after irrigation was stopped. Metronidazole was more effective in reducing motile forms, but the reduction was not significant at d 84. It was concluded that pulsating monojet subgingival irrigation as part of a simplified oral hygiene program, with or without an active antimicrobial agent at low concentration, is effective in reducing the motile and spirochete portions of the subgingival microflora. These effects might be enhanced and prolonged if suitable antimicrobial solutions of higher concentration were used.