bluuebunny/crossref_metadata_2025 huggingface dataset:
Subgingival plaque control by a simplified oral hygiene regime plus local chlorhexidine or metronidazole
Authors: Khoo J. G. L. , Newman H. N.
Published: July 2006

This study determined the effects of a simplified oral hygiene regime plus local applications of metronidazole or chlorhexidine on the subgingival microflora. Twenty‐one patients, with periodontal pockets 4 mm or deeper, underwent one session of scaling, root planing, and oral hygiene instruction (Bass method but without emphasis on interdental cleaning). Eight patients performed once daily subgingival irrigation with 0.2% chlorhexidine gluconate solution for 28 days. Thirteen patients had either 0.5% metronidazole in dialysis tubings or 40% metronidazole in acrylic resin strips inserted subgingivally once weekly, also for four weeks.

For each subject, subgingival plaque was obtained from two chemically treated (test) and one non‐chemically treated (control) pockets at days 0 (prior to scaling and root planing), 7, 14, 21, 28, 56, and 84. The subgingival microflora was assessed using darkfield microscopy. Bacteria were characterized as cocci, motile organisms, spirochaetes, and others (straight and curved rods, filaments and fusiforms).

Both chlorhexidine and metronidazole groups showed beneficial change still apparent at the end of the study (3 months). Great increases in proportions of cocci and reductions in spirochaetes and all other forms of bacteria were observed. Metronidazole reduced spirochaetes more but, unlike chlorhexidine, had a variable effect on motiles. Root planing alone had less effect. Generally, metronidazole and chlorhexidine appeared equally beneficial. It was concluded that in spirochaete‐dominated plaque, metronidazole may be preferred agent. Where motiles predominate, chlorhexidine may be the topical agent of choice.
Periodontal disease in three young adult populations
Authors: ÅNerud K. E. , Robertson P. B. , ÅNerud H. Löe, Å. , Boysen H. , Patters M. R.
Published: July 2006

The purpose of the present study was to assess periodontal destruction and related etiological factors in three young adult male populations in the U. S. A., Norway, and Sri Lanka. The clinical examination included the Plaque Index (Silness & Löe 1964), Retention Index for calculus, defective fillings, and gingival caries (Löe 1967), Gingival Index (Löe & Silness 1963), and Loss of Attachment (Ramfjord 1959).

Plaque accumulation, calculus deposition, and gingival inflammation were higher in interproximal than buccal areas. Plaque and Gingival Index scores remained constant over the entire age range in each population. The filling experience was high in Norway compared to the U. S. A. and Sri Lankan populations where few defective fillings were found. Caries related to the gingival margin were rare in all three populations. Loss of attachment increased with age and was greater on buccal surfaces than mesial surfaces. The distribution of attachment loss was similar in the three populations, and the greatest attachment loss involved maxillary first molars, maxillary and mandibular first premolars, and mandibular incisors. Rates of attachment loss in these young populations were low, averaging less than 0.06 mm per year.
Distribution of certain subgingival microbial species in selected periodontal conditions
Authors: Savitt E.D. , Socransky S.S.
Published: July 2006

Nine commonly encountered subgingival species were enumerated in subgingival plaque samples from periodontally healthy, gingivitis, and adult and juvenile periodontitis subjects employing two elective and three selective media. Samples were also obtained for darkfield microscopy. Results indicated that Eikenella corrodens and Fusobacterium nucleatum were usually elevated in proportions in sites with gingivitis or destructive periodontal disease. Capnocytophaga gingivalis was associated with gingivitis whereas Capnocytophaga ochracea was found in higher proportions in subgingival plaques of subjects with juvenile periodontitis. Previous association of Actinobacillus actinomycetemcomitans with juvenile periodontitis was confirmed. Spirochetes and other motile organisms were found more frequently and in higher proportions in the three disease states and were very strongly correlated with pocket depth. Motile organisms were also positively correlated with levels of plaque and redness in contrast to cocci which showed a strong negative correlation with all clinical parameters recorded.
Cytopathic effects of Actinobacillus actinomycetemcomitans on monkey blood leukocytes
Authors: Taichman N. S. , Shenker B. J. , Tsai C.‐C. , Glickman L. T. , Baehni P. C. , Stevens R. , Hammond B. F.
Published: July 2006

The suitability of cynomolgus monkeys (Macaca fascicularis) for studies concerned with the biologic properties of Actinobacillus actinomycetemcomitans is the subject of the present investigation. We found that normal monkeys harbored leukotoxic strains of A. actinomycetemcomitans in subgingival plaque samples. Monkey peripheral blood PMNs and monocytes were killed following in vitro exposure to sonic extracts of leukotoxic strains of A. actinomycetemcomitans. Monkey sera were capable of inhibiting the leukotoxic properties of A. actinomycetemcomitans sonic extracts due to the presence of IgG antibodies which neutralized the leukotoxin. Similarly, sera from patients with juvenile periodontitis (but not normal human sera) abolished leukotoxin‐mediated killing of monkey PMNs. Monkey peripheral blood lymphoid cells were not killed by A. actinomycetemcomitans but demonstrated depressed responses to mitogens following pre‐incubation with A. actinomycetemcomitans sonicates prepared from either leukotoxic or “non‐leukotoxic” human strains. These studies suggest that cynomolgus monkeys may serve as a suitable in vitro and in vivo model for delineating more about host‐A. actinomycetemcomitans interrelationships in the etiology of human periodontal disease.
Preliminary characterization of material eluted from roots affected by juvenile periodontitis
Authors: Fine D. H. , Oshrain R.
Published: July 2006

Initial efforts were undertaken to characterize material eluted from the roots of diseased teeth obtained from patients with juvenile (JP) and chronic periodontitis (CP). Material eluted from sixteen of nineteen diseased roots was limulus positive; out of five normal roots, only one yielded limulus‐positive material (X2= 7.90; p < 0.01). Moreover, heat treatment reversed the limulus positive response of material from seven of the eight limulus‐positive JP roots, but had no effect on six of the eight limulus‐positive extracts from CP roots (X2= 6.36; p < 0.02). Preliminary evidence suggests the presence of a heat‐sensitive, moderately acid‐stable, limulus‐activating protein in material eluted from roots affected by juvenile periodontitis.
Microscopic evaluation of root surface associations in vivo
Authors: Fine D. H. , Greene L. S.
Published: July 2006

These preliminary studies were undertaken to test the effectiveness of a new procedure for in vivo examination of interactions between bacteria and root surfaces. For this purpose, four patients with juvenile periodontitis, four with chronic periodontitis, and four normal subjects were selected. For this procedure, root segments 8 mm long, 2 mm wide, and 150–200 μm thick were prepared from normal teeth extracted for orthodontic reasons. These root segments were then sterilized with ethylene oxide. In each subject, one root segment was placed in direct apposition to the mesial surface of a previously scaled lower first molar and positioned to extend 4–5 mm supragingivally and 2–4 mm subgingivally. Root strips were removed after seven days, fixed, dehydrated, and embedded in Spurr's resin.

Light and electron microscopic examination of sections from the supragingival portion of root segments revealed bacteria within the root surface in all normal and chronic periodontitis subjects and in two juvenile periodontitis subjects. A nonpenetrating flora was associated with the supragingival portion of the root segments from the other two juvenile periodontitis subjects.

Subgingivally, root segments from normal subjects were colonized by junctional epithelium with hemidesmosomes and wide intercellular spaces in which bacteria and polymorphonuclear leukocytes were occasionally seen. In root segments from chronic periodontitis patients, the surface appeared to be occupied by Gram (+) bacteria that were morphologically similar to those seen supragingivally in samples from the same patients. Polymorphonuclear leukocytes and a sparse, loosely associated flora was present on the surface of the subgingival portion of the root samples from juvenile periodontitis patients.

The contrast between the presence of bacteria within the supragingival and subgingival portions of root segments obtained from chronic periodontitis patients and the absence of bacteria in root segments from all subgingival samples and two supragingival root samples in the juvenile periodontitis group was considered the most provocative result of the study. It was concluded, on the basis of these results, that the procedure used for the preparation and placement of root segments overcomes limitations inherent in other techniques for the study of subgingival events and permits clear discrimination between patterns of bacterial colonization of the root surface in different subject populations.
Relationship between linear and area measurements of radiographic bone levels utilizing simple computerized techniques
Authors: Jeffcoat M. K. , Williams R. C.
Published: July 2006

Three methods were used to measure the percent alveolar bone remaining about the premolar teeth in standardized perapical radiographs from eight female beagle dogs. The first method utilized straight‐line measurements of bone remaining along the tooth root, the second method used measurements which followed the curved path of the tooth root, and the third method measured the area of tooth root supported by alveolar bone as projected on a radiograph.

An inexpensive digitizer‐computer system was used to determine linear, curvilinear, and area measurements. The percent remaining alveolar bone determined by each of these three methods were compared in order to determine the simplest technique which most completely describes the bone remaining about each tooth root. There was no significant difference between the percent bone remaining determined by straight line and curvilinear measurements. Similarly, there was no significant difference between straight line and area measurements of percent remaining alveolar bone when there was little loss of alveolar bone (<15%). However, when there was moderate to severe bone loss on the radiograph (>15% loss), area measurements were significantly lower than linear measurements. The relationship between area measurement and linear measurement may be described by a quadratic equation. These data indicate that simple linear measurements of percent remaining alveolar bone on a radiograph may be transformed to the more complete area description of percent remaining alveolar bone using a quadratic equation. Thus, in beagles, simple linear measurements of percent remaining alveolar bone may be used to provide as complete a description of radiographic support as the more complex area measurements.
Histopathological effects in the palate of the rat induced by injection with different black‐pigmented Bacteroides strains
Authors: Roeterink C. H. , van Steenbergen T. J. M. , de Jong W. F. B. , de Graaff J.
Published: July 2006

The present investigation was carried out in order to study the histopathological effect and virulence of different black‐pigmented Bacteroides species on both soft and hard tissues in an animal model. Male Wistar rats were injected in the palate next to the first right molar with 30 μl of a bacterial suspension containing 5 × 1010 viable cells per ml. To determine the difference in virulence the histopathological effects were studied five days after injection.

All strains tested caused a submucosal infiltrate at the injection site, consisting of mononuclear cells, mainly lymphocytes, monocytes and fibroblasts. These inflammatory responses were accompanied by devitalization and resorption of bone. Simultaneously active osteoblasts and bone formation were observed. Strains of Bacteroides asaccharolyticus, Bacteroides melaninogenicus, Bacteroides corporis, and Bacteroides loescheii caused a less prominent devitalization of the palatinal bone than strains of Bacteroides gingivalis and Bacteroides intermedius. Strains of the latter species caused often a nasal infiltrate and abundant bone formation at the nasal side of the palatinal bone. B. asaccharolyticus and B. melaninogenicus scarcely caused signs of a reaction at the nasal side of the palatinal bone.

In a second longitudinal study the histopathological effects of B. gingivalis strain HG 66 were investigated. The inflammation was characterized by a rapid influx of polymorphonuclear cells within 2 to 4 hours. These cells gradually diminished and were replaced by a mononuclear infiltrate. One of the most characteristic features accompanying the inflammation was the disappearance of the periosteum. After two days a recovery of periosteum was observed and the osteoblasts became active in new bone formation. Devitalization from the palatinal bone started about 8 hours after injection and could be seen until 10 days after injection. No inflammatory reaction or devitalization of bone could be observed 15 days after injection.
Oral odors in early experimental gingivitis
Authors: Kostelc J. G. , Preti G. , Zelson P. R. , Brauner and L. , Baehni P.
Published: July 2006

Volatile chemicals were isolated from mouth air and from incubated whole saliva of 5‐matched pairs of male subjects who participated in a 30‐day experimental gingivitis protocol. Endogenous oral chemicals were monitored by GC/MS and GC/FPD during the test period. Malodorous sulfur compounds of mouth air were found to increase quantitatively in subjects with gingivitis as compared to control subjects. Salivary volatile production increased with deterioration in gingival health and, conversely, decreased with maintenance of optimal periodontal condition.
Reliability of volume measurements with the new Periotron® 6000
Authors: Bickel Matthias , Cimasoni Giorgio
Published: July 2006

A new device, the Periotron 6000®, has been proposed to estimate small amounts of gingival crevicular fluid. In the present investigation, small volumes of four different liquids (saline, saliva, plasma, and crevicular fluid) collected with small capillaries have been delivered on to Periopaper® strips. The amounts of liquids on the strips were determined with the Periotron.

High correlations between the fluid volumes and the Periotron readings were found. A calibration curve of the measurements made with crevicular fluid with its 5% tolerance and confidence limits is given. The slope of linear regression found in our investigation was at 3.5 nl per unit, thus significantly below that described by the manufacturer (5 nl/unit). Taking into account this fact, the Periotron, however, is a very reliable device to study gingival crevicular fluid in clinical investigations.
Whole cell agglutination and dextran binding in oral Actinomyces species
Authors: Kimura Shigenobu , Koga Toshihiko , Hamada Shigeyuki
Published: July 2006

Dextran‐induced agglutinability was studied with whole cells of 36 strains of oral Actinomyces species, including Actinomyces viscosus, Actinomyces naeslundii, Actinomyces israelii, and Rothia dentocariosa. Cells of seven A. viscosus strains of rodent origin were agglutinated upon addition of dextran T2000 (mean molecular weight, 2 × 106) and bound more [14C]‐dextran, which was synthesized by Leuconostoc mesenteroides dextransucrase from [14C]‐sucrose, than cells of A. viscosus of human origin.
The occurrence and activity of extracellular matrix vesicles in rat alveolar bone after the induction of local inflammation by bacterial products
Authors: Sela M. N. , Muhlrad A. , Bab I. , Deutsch D. , Setton A. , Sela J.
Published: July 2006

Periodontal inflammation was induced in rats by injection of bacterial sonic extracts isolated from Gram negative gingival pathogens: Capnocytophaga sputigena and Actinobacillus actinomycetemcomitans. The inflammatory reaction was characterized by a massive leukocytic infiltration, granulation tissue, and abscess formation. In addition, bone resorption and primary bone formation via extracellular matrix vesicles were observed. Matrix vesicle fractions obtained from the alveolar bone of rats with inflammation revealed an increase of acid phosphatase activity as compared to controls. Studies of alkaline phosphatase activity in the vesicular fractions revealed no differences between experimental and control groups. The possible role of bacterial products in alveolar bone remodeling in the light of the enzymatic alterations and morphological observations is discussed.
Effects of lathyrism on mouse molar migration
Authors: Dreyer C. W. , Sampson W. J.
Published: July 2006

Previous cursory reports of lathyritic alveolar bone activity prompted a histologic and radioautographic investigation of tooth migration patterns in normal and lathyritic mice. Using Sharpey's fiber patterns and the distribution of (3H)‐proline radioactive label as indicators, bone deposition was found on distal, occlusal, and buccal facing alveolar surfaces and revealed normal tooth migration to be in a distal, occlusal, and buccal direction. In addition, the radioautographic label confirmed the reliability of using Sharpey's fiber patterns as directional indicators. Over a forty‐day lathyritic period a progressive disturbance of Sharpey/principal fiber attachment at the bone surface plus radioautographic inactivity indicated that the distal and buccal vectors of migration had ceased. However, occlusal migration appeared to continue. These results were considered to be a likely consequence of the duration and severity of the lathyritic change and the difference in turnover times between the supracrestal and periodontal ligament collagen fibers, with further consideration to the occlusion, ultrastructural, and vascular changes being required.
Crevicular fluid prostaglandin E levels as a measure of the periodontal disease status of adult and juvenile periodontitis patients
Authors: Offenbacher S. , Odle B.M. , Gray R.C. , Van Dyke T.E.
Published: July 2006

The measurement of crevicular fluid PGE (CF‐PGE) as an indicator of periodontal disease status was investigated. The association between CF‐PGE levels and the PGE content of the adjacent periodontal tissues was found to be highly significant (P=5.3 × 10−6). The high correlation (r=0.925) between the log CF‐PGE level and the tissue PGE concentration indicates that CF levels can be used to reliably predict tissue levels. The CF‐PGE measurements at each periodontal site were found to be highly reproducible. Samples from adult and juvenile periodontitis patients demonstrated that the mean CF‐PGE levels were correlated with disease severity, as determined by mean attachment loss. The mean CF‐PGE level in juvenile periodontitis patients was almost three‐fold higher than that present in adult periodontitis (144.0 ± 28.0 ng/ml vs 57.5 ± 8.7 ng/ml, mean ± S.E., significant at P = 0.002). The use of CF‐PGE concentrations as an indicator of disease activity (i.e. longitudinal attachment loss) cannot be demonstrated by this cross‐sectional study. However, the CF‐PGE measurement has been demonstrated to be a non‐invasive, sensitive, reproducible, and reliable reflection of tissue levels of PGE2. The association of increasing levels of CF‐PGE with increased severity and aggressiveness of disease is consistent with PGE as an inflammatory mediator of tissue destruction.
Age and diet composition in relation to experimental periodontal destruction in hamsters
Authors: Mikx F.H.M. , Maltha J.C. , Wolters‐Lutgerhorst J.M.L. , Franken H.C.M.
Published: July 2006

Hamsters from 30 days upto 150 days of age were used to study the effect of different dietary regimens, including pellets, powdered pellets, and powdered purified diets with and without sucrose. The experimental period was 30 days. The periodontal destruction was measured macroscopically and histologically while bone remodelling was scored using Procion Brilliant Red® as a marker. Plaque amount, infiltrate, and osteoclasts were evaluated in the histological sections. Actinomyces, Propionibacterium, Veillonella, Fusobacteria, and Bacteroides were identified in most plaque samples. Spirochetes were never observed. The texture of the diet had neither an effect on the amount of dental plaque nor on the bone level measurements. The difference in bone level was related with the presence of sucrose in the diet and the age of the hamsters. Animals of 30 days old at the start of the experiment showed, in contrast to the older animals, no difference in bone level after the experimental period.

It is concluded that in hamsters on a 16% sucrose diet the growth of alveolar bone is diminished, or even the destruction of alveolar bone is induced. This process in hamsters is age related and might be analogous to that in man.
Evaluation of serum‐containing substrates for cultivation of oral spirochetes
Authors: Fiehn N.‐E. , Frandsen A.
Published: July 2006

The aim of this study was to evaluate eight different solid substrates with rabbit serum and ±5% blood for suitability to support growth of oral spirochetes in subgingival plaque samples from patients with advanced destructive periodontitis. In order to inhibit growth of other bacteria, nine antibiotics were added to the substrates singly or in combinations. Four of the tested substrates supported growth of oral spirochetes, BHIA‐SC and GM‐1 (both with blood), yielding the best results with a recovery of about 4%. The antibiotics best suited for the suppression of other bacteria were rifampicin, polymyxin B, and nalidixic acid.
Necrotizing ulcerative gingivitis in beagle dogs
Authors: Mikx F.H.M. , Hug H.U. , Maltha J.C.
Published: July 2006

The induction and transmission of Necrotizing Ulcerative Gingivitis (NUG) lesions in beagle dogs have been reported previously. In the present experiments the contagious nature of these NUG lesions was further investigated by studying the unilateral induction and the intraoral transmission of NUG lesions. Six beagle dogs were treated with Kenacort A40®. The control quadrants of their dentition were cleaned while the experimental quadrants were not. The experimental quadrants were inoculated with pooled dental debris from the same dogs. NUG lesions were induced in the experimental quadrants, but NUG lesions were observed also at some sites of the control quadrants. In the second part of the experiment, reinoculation of non‐affected experimental sites with debris from lesions of the same dog or cage companion increased the number of NUG lesions in both experimental and control quadrants.

The study of experimental intraoral transmission of NUG lesions was restricted to the non‐diseased sites in experimental and control quadrants. Topical application of debris of NUG lesions on the test sites did not spread the disease to these sites. Microscopic and cultural evaluation of subgingival microflora revealed no differences in the presence of Bacteroides, Fusobacteria, Spirocheata, and Spirillum in relation to the presence or absence of NUG. Three different types of black pigmental Bacteroides species were observed. It is concluded, that the morphology of the interdental sites is of great importance for the clinical occurence of NUG lesions and that the increase in number and severity of lesions after local reinoculation indicates that in the phase of primary infection, iatrogenic NUG lesions might be possible in a susceptible host.
Necrotizing ulcerative gingivitis in beagle dogs
Authors: Hug H.U. , Maltha J.C. , Mikx F.H.M.
Published: July 2006

Clinical studies in beagle dogs have indicated that NUG occurs at sites of predilection. The purpose of the present investigation was to compare the histologic characteristics of interdental sites exhibiting clinical NUG with those without clinical NUG in relation to the presence or absence of interproximal contacts.

In six beagle dogs, aged three years, NUG was experimentally induced. At the end of a longitudinal clinical study the dogs were sacrified and prepared for histological evaluation. The occurrence of ulcerations in the col epithelium and the adjacent epithelium is related to the clinical NUG scores as well as to the presence of interproximal contact. The same holds true for the presence of an inflammatory infiltrate in the subjacent connective tissue. Ulcerations of the col epithelium as well as the infiltrate subjacent to this area appears to be related to the clinical NUG scores, but the ulcerations in the sulcular and junctional epithelium are not, nor is the infiltrate subjacent to these epithelial areas.

The results suggest two possibilities. The first is that the clinical NUG score is insufficient to trace the sulcular expression of the disease, and the second possibility is the existence of two different periodontal diseases in these beagle dogs.
The effect of notching and citric acid on healthy root surfaces in dogs
Authors: Gara George G. , Adams Donald F.
Published: July 2006

The purpose of this study was to determine the following on healthy root surfaces: (1) the effect of placement of a notch within dentin on the formation of cementum and/or connective tissue attachment and (2) the effect of citric acid on the notched root surface on the formation of cementum and/or connective tissue attachment. Five young adult dogs were used in the study. Full thickness buccal flaps were reflected on canines, P3, P4, and M1, 4 mm of buccal bone was removed, and the roots carefully planed. One, two, or three parallel notches were placed in the exposed root surface of each tooth. The root surfaces were then treated with either citric acid or saline, and the flaps were replaced and sutured. Animals were sacrificed at intervals of 5 weeks, 9 weeks, 10 weeks, and 12 weeks. Block specimens were examined in step‐serial fashion via light microscopy. The data pool consisted of 19‐matched paired teeth, including 72 roots. Healing responses in a specific notch or on an isthmus varied, including epithelium‐root, connective tissue‐cementum‐root, bone‐connective tissue‐root, ankylosis, or any combination.

There was a statistically significant increase in the formation of connective tissue attachment, cementum, and bone toward the apical part of the notches and isthmuses. Epithelium interfaces were significantly higher in notches compared with isthmus surfaces (α= 0.05). The frequency of connective tissue attachment on isthmuses was statistically greater than in notches (α= 0.05). When citric acid was used, in comparison to saline, cementum was observed significantly more often in the coronal portion of the lesions (α= 0.05). This study indicates that citric acid applied to healthy root surfaces in dogs enhances cementum formation in areas farther coronally to the alveolar process than areas treated with saline. Notching per se does not enhance cementum and/or connective tissue attachment. There was no difference in the incidence of ankylosis between saline and citric acid treated specimens.
In vitro sorption of IgG to cementum
Authors: Fine D. H. , Wilton J. M. A. , Caravana C.
Published: July 2006

The nature of the interaction between root surfaces and gingival fluid proteins has not been studied. Therefore, a series of in vitro investigations were undertaken to develop an assay to determine sorption of prominent gingival fluid proteins to the cementum.

In initial studies extracted teeth were immersed in various concentrations of whole human serum and incubated with rabbit anti‐IgG, IgA, IgM, and C3 followed by anti‐peroxidaseperoxidase bridging reagents. Of the proteins analysed IgG sorbed to the highest degree in gross and microscopic evaluations. Remaining studies focused on quantifying IgG sorption, and thus root segments of known surface area were prepared and immersed in 125I‐IgG. Sorption of IgG was calculated as 21.5 ± 0.27 ng/mm2 when IgG was added at concentrations found in gingival fluid. Root fragments immersed in non‐IgG human serum reconstituted with specific amounts of 125I‐IgG, sorped only 3.4 ± 0.9 ng/mm2 of IgG, and direct measurement of IgG sorption in whole serum by the ELISA method gave comparable results. Moreover, pre‐coating of root segments with non‐IgG serum followed by incubation with 125I‐IgG resulted in 74% inhibition of IgG binding.

Results suggest that serum protein sorption to root surfaces can be quantitated and may be non‐specific and concentration dependent with respect to IgG.
Gingival sulcular leukocytes in periodontitis and in experimental gingivitis in humans
Authors: Thurre Carlos , Robert Marc , Cimasoni Giorgio , Baehni Pierre
Published: July 2006

Leukocytes may play an important defensive role against plaque microorganisms in the periodontium. The aim of the present study was to characterize some functional and morphological aspects of sulcular leukocytes in periodontitis and in experimental gingivitis in humans. In a cross‐sectional study, cells were collected from periodontal pockets or from gingivitis (control) sites of patients with periodontitis. In a longitudinal study, cells were obtained from experimental or from control sites during a split‐mouth experimental gingivitis. Leukocytes were examined for cell numbers, viability, phagocytic function, and morphology.

The cell numbers in periodontal pockets were higher than in control sites but the cell viability had a tendency to decrease. A significant decrease was also observed in the percent of leukocytes capable of phagocytizing Candida albicans in vitro in periodontitis sites compared to gingivitis sites. In the experimental gingivitis, the cell numbers showed a significant increase from day 0 to day 21 of the non‐brushing period in the experimental sites when compared to the control sites. However, the cell viability did not vary significantly between the experimental and the control sites during the experimental period. No significant variations were observed in the leukocyte in vitro phagocytic function during the same period. Polymorphonuclear leukocytes collected from the sulcus presenting different clinical situations showed various degrees of phagocytosis, loss of lysosomes, and cell lysis, but no correlation could be established between these observations and the clinical status.
Measurement of eight prostaglandins in human gingival and periodontal disease using high pressure liquid chromatography and radioimmunoassay
Authors: Ohm K. , Albers H.‐K. , Lisboa B. P.
Published: July 2006

Eight prostaglandins (PG) of biological importance, namely PGE,. PGE1 13,14‐dihydro‐15‐keto‐PGE, (DHK‐PGE2), PGF2α, PGF1α, 13, 14‐dihydro‐15‐keto‐PGF2α (DHK‐PGF2α, 6‐keto‐PGF1α, and thromboxane B2 (TxB2), were measured in the human gingiva in a healthy state, gingivitis. and periodontitis. High pressure liquid chromatography (HPLC) in combination with radioimmunoassay (RIA) was employed for quantitative analysis. The advantages of HPLC over the classic silicic acid column chromatography of prostaglandins were discussed. All prostaglandins considered were shown to increase during advancing periodontal destruction. The most quantitatively significant endoperoxide metabolites at every stage of inflammation were TxB2 and 6‐keto‐PGF1α followed by PGE2. DHIK‐PGE2, PGE1, PGF1α. PGF3α, and DHK‐PGF2α in decreasing order.
Effects of bone remodeling on continuity of transalveolar fibers of the mouse periodontium
Authors: Johnson Roger B.
Published: July 2006

The effects of physiologic bone remodeling on the continuity of transalveolar fiber bundles of the interdental bone septum is a subject of controversy. The present study demonstrated that these fiber bundles transversed resting and reversal lines of the crestal and middle third of the interdental septum of the mouse. In some areas of the apical third of the septum, transalveolar fiber bundles terminated at reversal lines. Channels surrounding these fiber bundles terminated at reversal lines but transversed resting lines. Thus, the present study suggested that remodeling of alveolar bone has little effect on the continuity of transalveolar fiber bundles of the crestal and middle thirds of the interdental septum of the mouse.
Orientation of cells in the experimental periodontal wound
Authors: Aukhil I. , Schaberg T. V. , Lutins N. D.
Published: July 2006

This pilot study was designed to examine the cellular orientation when a second substratum was placed close to the surgically denuded root surface in an experimental periodontal wound. Using mucoperiosteal flaps, windows of standard dimensions were cut on the buccal aspect of mandibular premolars in two beagle dogs. In the experimental wound, a sheet of decalcified bone matrix (DBM) was placed adjacent to the surgically denuded root surface to serve as the second substratum. Both experimental and control wounds were then covered with millipore filters and the flaps were replaced and sutured. Histologic results at 4 and 7 days suggest that a second substratum placed close to the denuded root surface may favorably affect cellular orientation.
The effect of topically applied fluorides on the surface free energy of human dentin
Authors: de Jong H. P. , de Boer P. , van Pelt A. W. J. , Busscher H. J. , Arends J.
Published: July 2006

The surface free energy γs of human dentin treated with sodium fluoride, acidulated phosphate fluoride, and aminfluoride solutions has been determined by means of contact angle measurements. Application of an aminfluoride solution slightly increased the total surface free energy from 75 to 80 erg. cm−2. The γs values of dentin after a neutral sodium fluoride application decreased to 62 erg. cm−2. APF solutions hardly influenced the surface free energy γs. This study showed that fluoride applications change the surface free energy of human dentin.

Extrapolation of the results of this study and the in vitro results on cell spreading indicated that aminfluoride applications might be favorable for the reattachment of periodontal tissues.
Alteration of fimbriation and cell hydrophobicity by sublethal concentrations of tetracycline
Authors: Peros W. J. , Etherden I. , Gibbons R. J. , Skobe Z.
Published: July 2006

The effect of growth in the presence of sublethal concentrations of tetracycline on the extent of fimbriation and surface hydrophobicity of strains of Actinomyces viscosus and Bacteroides gingivalis, two species frequently isolated from patients with rapidly progressing periodontitis, was determined. Negatively‐stained cells of A. viscosus strains LY7 and S2 and B. gingivalis strain 381 showed a dramatic reduction in the number of fimbriae on their surface when grown in the presence of 50% of the minimum inhibitory concentration of tetracycline as compared to untreated controls. Similar observations were made with fixed, lanthanum‐stained thin sections. In addition to long fimbriae, the A. viscosus strains possessed stubby, densely staining tufts on their surface which were not affected by tetracycline. The hydrophobicity of antibiotic‐grown A. viscosus and B. gingivalis cells was also found to be significantly reduced. The decrease in fimbriation and surface hydrophobicity of A. viscosus and B. gingivalis when grown in the presence of low concentrations of tetracycline may explain their reduced ability to attach to experimental pellicles. These observations suggest that part of the efficacy of tetracycline therapy for destructive forms of periodontal diseases may be mediated by an alteration of the adhesive properties of subgingival bacteria which affected their colonization.
The pH of human crevicular fluid measured by a new microanalytical technique
Authors: Bickel Matthias , Cimasoni Giorgio
Published: July 2006

In physiological and pathological conditions, the pH of the crevicular fluid may play a significant role on the structure and function of the gingival crevice. In the present investigation the pH of human crevicular fluid was determined by a new microanalytical technique. The fluid was collected in 32 sites (19 patients) with capillary tubes. The tip of a double barreled, neutral carrier based microelectrode, highly selective for H+ ions was introduced directly into the capillary tubes containing either the samples or the reference solutions. In each sampling site, the GI and the crevicular fluid volume were recorded and correlated with the pH. As the inflammation increased, an elevation of pH from 6.90 to as much as 8.66 was observed. These values have been measured at 20°C in absence of CO2.

Whether this increase is due to the bacterial flora or to any metabolic activity in the crevice area is not clear at the moment.
Labelling of gingival and dermal mast cells with and without degranulation by 48/80
Authors: Farnoush Ali , Nuki Klaus
Published: July 2006

To investigate the mode of proliferation of mast cells in non‐inflamed gingiva and skin of Swiss Webster mice, single and multiple pulses of 3H‐thymidine and autoradiographic procedures to detect DNA synthesis were used in conjunction with selective staining techniques. A labelling index was found indicating a rate of turnover so low that kinetic studies on normal tissue would be impractical. It was found that the histamine releaser compound 48/80 could alter mast cell populations and thus provide a suitable model in which to further examine the kinetics of mast cells.

Studies of experimentally altered gingival and skin mast cells produced a pattern of mast cell labelling which suggested derivation of new mast cells by local setfreplication. Evidence was obtained that labelled mast cells observed one hour after labelling had divided to produce two daughter cells and that the rate of increase in the number of labelled mast cells following repeated pulse labelling for up to 20 days was linear and did not suggest major recruitment of mast cells from a distant source during this period.
Root resorption following periodontal flap procedures in monkeys
Authors: Magnusson I. , Claffey N. , Bogle G. , Garrett S. , Egelberg J.
Published: July 2006

The effect of a periodontal flap procedure, that included citric acid root conditioning and closure of the wounds by suturing of coronally elongated flaps, was studied in mandibular premolars and molars in monkeys. Three months in advance, to prepare for this regenerative procedure, every other tooth in the mandibular posterior segments was extracted and the alveolar bone level reduced to a level approximately 5 mm apical to the cemento‐enamel junction around the remaining teeth. Histologic observations of biopsies removed 6 months after the regenerative surgery disclosed resorption of the treated root surfaces in the majority of specimens. Citric acid treatment of the root surfaces cannot have been primarily responsible for the resorption, as control surfaces, on which acid was not used, also displayed resorption. Resorption occurred most commonly on surfaces in which the junctional epithelium showed limited apical migration and was located 2 mm or more coronal to the apical extent of root planing.
Assessment of inter‐examiner agreement in scoring periodontal disease
Authors: Mann Jonathan , Goultschin Joseph , Call Richard L.
Published: July 2006

A study population of 20 patients exhibiting a wide range of severity of inflammation were examined using the Periodontal Index (PI) and the Gingival Index (GI). Two examiners, an epidemiologist and a periodontist were provided with a reading list of the relevant literature on the two indices and ample discussion time, but were not allowed to engage in clinical calibration sessions prior to the beginning of the examinations. The results showed higher GI and PI scores obtained by the epidemiologist when compared with the scores obtained by the periodontist. High correlation coefficients were found between the GI and PI scores for both examiners. The results obtained indicate that with limited calibration between examiners, a high correlation was found when the Periodontal Index or the Gingival Index were used, even though the absolute results fluctuate widely. In order to avoid misinterpretation of tissue appearance by a second examiner, the order of examination in pilot studies conducted to assess inter‐examiner agreement should be randomly switched between examiners.
The relationship of probing depth and total microscopic counts to differential subgingival plaque morphology
Authors: Pihlstrom B. L. , Liljgemark W. F. , Schaffer E. M. , Wolff L. F. , Smith J. A. , Bandt C. L.
Published: July 2006

The goal of this study was to investigate the relationship between probing depth, total microscopic counts, and specific microbial forms in subgingival plaque from young adults. Subgingival plaque samples were collected and probing depth recorded from 415 mesial surfaces of maxillary first molars in 266 individuals aged 20–40. Using dark field microscopy in a Petroff‐Hausser chamber, total organisms in each sample were estimated, as well as proportions of spirochetes, motile and non‐motile rods, cocci, and total motile organisms. Limits for decile ranks based on total organisms were determined and the mean percentage of each microbial form within each decile rank was calculated. Correlation coefficients (r) were computed between the dependent variables of microbial forms and the independent variables of total organisms, probing depth, and the combination of total organisms and probing depth. The percentage variability of microbial forms that could be explained by the regression of each dependent variable on each independent variable or combination of independent variables was estimated by r2. The results indicate: (1) differences in bacterial composition of subgingival plaque are associated with differences in total subgingival microorganisms and in probing depths, (2) approximately 15–20% of the variability in the proportions of microbial forms in subgingival plaque can be explained by differences in total subgingival microorganisms, (3) two to four times more variability in the proportions of microbial forms in subgingival plaque can be explained by differences in total subgingival microorganisms than can be explained by differences in probing depths, and (4) considerable variability in proportions of microbial forms in subgingival plaque remains that cannot be explained by either differences in total subgingival microorganisms or by differences in probing depths.
Human antibody‐dependent cellular cytotoxicity and natural killer cytotoxicity in periodontal disease
Authors: Tsoumis G. S. , Singh Gyan , Dolby A. E.
Published: July 2006

Spontaneous cell mediated cytotoxicity (SCMC) and antibody‐dependent cell mediated cytotoxicity (ADCC) were examined in 25 patients with periodontal disease and a group of 25 age and sex matched control subjects. SCMC and ADCC were evaluated from the 51Cr activity released when peripheral blood lymphocytes were cultured with 51Cr labelled K562 and L929 cells, respectively. Four lymphocyte: target cell ratios were used, 50: 1, 25: 1, 12.5: 1, and 6.25: 1 in triplicate. There was no significant difference (p>0.05) in the SCMC and ADCC between the two groups. However, a very significant positive correlation (p < 0.001) was found between the degree of periodontal disease (Russell 1956) and SCMC.
Ultrastructural and immunohistochemical similarities in the attachment of human oral epithelium to the tooth in vivo and to an inert substrate in an explant culture
Authors: Salonen Jukka , Santti Risto
Published: July 2006

Laminin and type IV collagen were localized in the mucosal and vascular basement membranes in sections of human deciduous and permanent teeth with the junctional epithelium still in situ. These essential basement membrane constituents were also demonstrable at the epitheliumconnective tissue interface under the stationary and migrating epithelium (epibolus) of cultured palatal mucosa. The contact of the epithelium with the cementum or enamel in vivo and with a Millipore® filter in vitro, instead of connective tissue, influenced the chemical composition of the epithelial attachment apparatus. Laminin was found both in the epithelial attachment on the tooth and within the Millipore® filter under the migrating epithelium. Type IV collagen was not, however, localized in the attachment apparatus on the tooth nor in the epithelium‐filter interface despite the presence of a unit attachment apparatus with basal lamina, hemidesmosomes, and anchoring filaments along the filter.

These findings support the idea of the tooth as an inert substrate for epithelial cells and provide further grounds for the application of the described in vitro model to the study of the chemical constituents of the epithelial attachment.
The periodontal status of prospective and renal transplant patients
Authors: Tollefsen Tore , Johansen Jan R.
Published: July 2006

The periodontal condition of 33 prospective and 26 renal transplant recipients was compared with that of systemically healthy subjects, matched for age, teeth present, social status, and sex. One group comprised 21 patients with uremia while the second group consisted of 12 other patients treated with hemodialysis. Ten patients later underwent renal allotransplantation and were also included in the third, immunosuppressed group. The three renal patients groups had significantly (p<0.05) higher mean plaque scores than the control groups. By contrast, the hemodialysis and immunosuppressed patient groups showed significantly (p<0.05) fewer gingival bleeding points than their respective controls. Progressive uremia and immunosuppression by drugs thus entailed less clinical gingivitis. The mean pocket depths and alveolar bone loss, as judged from intra‐oral roentgenograms, were similar among the paired groups. Regression lines of the amount of bone loss by age were computed for the combined renal patients (49 subjects) and the control persons, respectively. The regression slopes were heterogenous (F=6.3; p<0.05). Renal patients above 49 years of age (39% of the group examined) showed significantly (p < 0.05) less bone loss than the control persons. The uremic state and immunosuppression by drugs may retard periodontal breakdown in humans.
Periodontal status in patients before and after renal allotransplantation
Authors: Tollefsen Tore , Johansen Jan R.
Published: July 2006

Sixty‐five dentate prospective and renal transplant patients, aged 17 to 68 years, were examined. Thirty‐two patients had uremia, while 16 patients were on hemodialysis. The transplant group comprised 32 patients maintained on an immunosuppressive regimen, of whom 15 persons were recruited from the first two groups. The number of bleeding gingival units (GI=2) was significantly (p<0.05) associated with the presence of dental plaque in all groups. The transplant recipients had significantly (p<0.05) less dental plaque than the other two groups. The mean gingivitis score was highest among the uremic patients (p<0.05). The groups were similar regarding the number of existing teeth, pocket depth, and radiographic alveolar bone height. However, groups formed according to systemic diseases showed that patients with diabetes had suffered from significantly (p<0.05) more alveolar bone loss than the other patients. Eleven prospective and 18 transplant recipients were re‐examined from 1/2 to 6 years later. Within groups, pocket depths, plaque, and gingivitis scores had not changed significantly. Twenty‐six such patients had been followed for 81±34 months. The mean yearly rate of radiographic bone loss did not change significantly during chronic renal failure. The results indicate that periodontal disease is not aggravated under reduced immunocapacity.