bluuebunny/crossref_metadata_2025 huggingface dataset:
The pattern of alveolar bone activity during development and eruption of the molar in the rat
Authors: Kameyama Yoichiro
Published: July 2006

The pattern of alveolar bone activity around the developing and erupting mandibular first molar of the rat was studied by autoradiography. The rats were hilled at 1 day and 1, 2, 3 and 4 weeks after birth. One hour prior to sacrifice, they were injected with 3H‐proline intraperitoneally. At one day after birth, the alveolar bone surfaces surrounding the tooth germ were unlabeled. At one week, the surface of the alveolar bone mesial to the developing tooth crown revealed heavy labeling, whereas the remaining surfaces surrounding the crown were unlabeled. The interdental septum between the first and second molars appeared at this stage. lts mesial surface was unlabeled troughout the four stages. Formation of the interradicular septum was ohserved at two weehs, and the future crestal area displayed very intense labeling. At three weeks, the crestal, mesial and distal surfaces of the interradicular septum showed heavy labeling. However, the apical one‐third of the mesial surface of the septum was unlabeled at four weeks. The surfaces of the fundic bone just beneath the primitive pulp chamber and beneath the open ends of the roots were unlabeled throughout the entire period. At three and four weeks, the interdental and interradicular crests exhibited very heavy labeling, more intense than that at the crest of the alveolar bone mesial to the first molar.
Plaque inhibition and distribution of chlorhexidine in Beagle dogs
Authors: Davies R. M. , Hull P. S.
Published: June 2006

Twelve Beagle dogs were allocated to three equal groups on the basis of existing plaque scores. Two gels, one containing 0.5 per cent chlorhexidine digluconate, the other a placebo, were applied once daily to the teeth of separate groups of animals, the third group serving as controls. The chlorhexidine gel inhibited the formation of plaque and reduced the severity of gingivitis. In a further study the distribution of 14C‐labelled chlorhexidine was determined in the oral and systemic tissues of dogs after a single or repeated oral dose. Labelled material was observed in the superficial epithelial layers of all oral tissues; higher levels, of activity were present on keratinized than non‐keratinized surfaces. This process of adsorption was apparently reversible and no accumulation of chlorhexidine was detected in the mouth after repeated dosing. No absorption of labelled material through the oral tissues was observed.
Different modes of chlorhexidine application and related local side effects
Authors: Fløtra L.
Published: June 2006

In this short paper some data from clinical use of chlorhexidine outside dental institutions are presented. In these trials chlorhexidine mouthwashes, chlorhexidine dentifrices and chlorhexidine gel in cap splints have been utilized. Some comments were made upon related side effects.
Some antibacterial properties of chlorhexidine
Authors: Hennessey T. D.
Published: June 2006

The use of the antiseptic chlorhexidine as a therapeutic or prophylactic drug in dental or periodontal hygiene is a departure from the usual fields of use for this agent. Therefore, a review of some of its antibacterial properties is desirable.

The bacteriostatic spectrum of chlorhexidine * was determined: there was a wide spectrum of activity with gram‐positive cocci being especially sensitive (MIC 0.19 to 2.0 μg/ml). Exposure of suspensions of various bacterial species to chlorhexidine (0.02%) for 10 minutes at room temperature, reduced the viable organisms by about 99.99% in most instances. Addition of serum to the test system reduced the bactericidal action markedly. A study with Streptococcus mutans revealed that the presence of sucrose (5%) in the growth‐medium used for preparing bacterial suspensions, profoundly influenced the bactericidal activity. This is presumed to be the result off adsorption of chlorhexidine to extracellular polysaccharides.

Attempts to select Escherichia coli and oral streptococci resistant to chlorhexidine by serial passage in subinhibitory concentrations in vitro, indicated that mutants were rare. In contrast, mutants of E. coli resistant to ampicillin or streptomycin were selected with ease. Predictions of what might happen under clinical conditions (where oral organisms might be exposed to sublethal concentrations for very long periods of time) cannot be made from such laboratory experiments. No changes were observed in the susceptibility of faecal organisms of hamsters given chlorhexidine (50 mg/kg) daily by gastric catheter for 28 days but 100 mg/kg rapidly caused a lethal enteritis which was assumed to be the result of gross disturbances of the alimentary microflora.

A small study in three human volunteers is reported. Use of a mouthrinse (twice a day for up to seven weeks) containing chlorhexidine digluconate (0.2%) resulted in a slight but transient change in susceptibility of salivary organisms to the bacteriostatic action of the agent. Whether resistance will prove to be an obstacle to the use of chlorhexidine in prophylaxis, in the mouth can be decided only with more clinical experience.
Oral leukocytes and gingivitis in the primary dentition
Authors: Cox M. O. , Crawford J. J. , Lundblad R. L. , McFall W. T.
Published: July 2006

A survey was performed to evaluate the relationships among orogranulocytic migratory rale, gingival index and plaque index in a group of systematically healthy preschool children.

The fifty children selected for study had only primary teeth, no pharyngeal or extragingival inflammation and were taking no medication. Each child was subjectively scored for the amount of bacterial plaque and gingival inflammation present. The rate of migration of leukocytes into the oral cavity per 30 second period was determined from the last three of ten 30 second consecutive oral saliva rinses as an objective measure of gingival inflammation.

A minimal amount of localized mild marginal gingivitis was observed in the presence of a rather large plaque accumulation. No significant correlation was observed between rates of oral leukocyte migration and the degree of gingival inflammation. However, the leukocyte migratory rates in this group were quite low as compared to those found in adults by other investigators.
A histochemical study of hydrolytic enzymes in human tooth ontogeny
Authors: Larmas Liisi , Larmas Markku
Published: July 2006

Arylaminopeptidase and glycosidase activities were studied by histochemical staining methods in human tooth and supporting tissue ontogeny in order to demonstrate the possible metabolic differences in the differentiated and undifferentiated cells of the formation, modelling and re‐modelling metabolism of the tissue involved. The enzyme activities were studied using various N‐L‐ aminoacyl‐2‐naphthylamines and 1‐ and 2‐naphthol glycosides and ‐esters as substrates. The arylaminopeptidase activity (EC 3.4.11) was observed (1) in the basal cell layer of oral epithelium in the stomodeum, (2) in the subjacent mesoderm, (3) in the outer and (4) inner enamel epithelium, (5) in the dental papilla, (6) in the dental lamina, and (7) in the primordium of permanent tooth. No arylaminopeptidase activity could be observed in ameloblasts. odontoblasts. enamel, dentin, stellate reticulum and pulp, and the inner enamel epithelium also lost its activity during the stage of apposition. The following glycosidases were observed in the same structures as the arylaminopeptidases: β‐N‐acetylglucosaminidase (EC 3.2.1.30), β‐glucosidase (EC 3.2.1.21), β‐galactosidase (EC3.2.1.23). β‐glucuronidase (EC 3.2.1.31), as well as arylsulphatase (EC 3.1.6.1) The whole thickness of oral epithelium revealed β‐galactosidase and arylsulphatase activity, not only the basal cell layer. These observations were‐ thought to give support to the suggestions that differeniation is a stage of highly active metabolism and thus at the stage of apposition the cells of the outer enamel epithelium are actively differentiating.
Periodontal conditions in patients treated with dental bridges
Authors: Silness John
Published: July 2006

The periodontal condition of 362 proximal abutment tooth areas facing bridge pontics were compared with that of 362 contralateral tooth surfaces which were in contact with the neighbouring teeth. The Plaque Index (Silness & Löe 1964). the Gingival Index (Löe & Silness 1963) and the Margin Index (Silness 1970a) were recorded. Pocket depths were measured according to Glavind and Löe (1967). The pontics seemed to increase the index values (PII., GI), but had apparently little influence on the pocket depths of the proximal abutment tooth surfaces in the case of non‐subgingival retainer margins. Proximal abutment tooth surfaces with subgingival retainer margins showed a marked increase of the index values (PII, GI) and the depth of the pockets seemed to have increased. The increase of the index values should probably be interpreted as being the accumulated effects of the presence of pontics and the subgingival margins. The increase in pocket depth seemed mainly to result from the subgingival retainer margins.
A comparative study of the buccal and lingual gingival tissues of the vervet monkey
Authors: Fleisch L.
Published: June 2006

The buccal and lingual gingival tissues in the vervet monkey were compared. Blocks of fresh tissue, consisting of mandible and associated soft tissues, were prepared for histological examination. Coronal and transverse sections, 7 and 25 μm thick, were cut through the full thickness of the mandible and stained with haematoxylin and eosin, picromallory and a variety of elastic stains. Photomicrographs of step serial sections were enlarged to standard magnification for histometric analysis. The buccal epithelium is thicker and shows a greater degree of keratinization than the lingual epithelium. The rete pegs are more prominent and penetrate deeper into the lamina propria on the buccal aspect. There appears to be two sets of elastic fibres in the submucosa on the buccal aspect and only one on the lingual. The buccal elastic fibres consist of a sub‐epithelial plexus of fine fibres and a longitudinal set of thicker fibres. The lingual fibres are situated sub‐epithelially only. The presence and orientation of the elastic fibres may be associated with the functional demands of flexibility and resiliency on the two epithelia.
Trauma and progression of marginal periodontitis in squirrel monkeys
Authors: Polson A. M. , Kennedy J. E. , Zander H. A.
Published: June 2006

This investigation was designed to test the co‐destructive factor hypothesis that a traumatic lesion subjacent to marginal periodontitis alters the progression of the periodontitis and produces angular bony defects. Marginal periodontitis was produced around 28 mandibular teeth in 7 squirrel monkeys by tying a silk ligature at the gingival margin to facilitate plaque accumulation. Six months after inducing periodontitis a severe traumatic lesion was produced subjacent to the marginal periodontitis in 15 of these teeth by thermal injury via the root canal. These specimens (Group I) were analyzed from 3 days to 6 months after injury subjacent to the periodontitis. The duration of periodontitis in the remaining 13 teeth (Group II) was the same as Group I allowing a comparison between the groups. It was concluded that the presence of a severe traumatic lesion and its sequelae subjacent to a marginal periodontitis did affect the progression of the periodontitis when evaluated by apical migration of the junctional epithelium and loss of alveolar bone. Angular bony defects occurred only when periodontitis was induced around isolated tooth surfaces and were related to the presence or absence of the traumatic lesion. Angular defects may be related more to location of etiologic agent than a combination of co‐destructive factors.
Growth of dental plaque on hydroxyapatite splints
Authors: Lie Tryggve
Published: July 2006

A technique was developed for growing dental plaque in vivo on an artificial surface which contains hydroxyapatite. Splints made of hydroxyapatite crystals embedded in an epoxy resin were adapted and cemented to the buccal surfaces of maxillary teeth in human test subjects. The splints were left in place for 24 or 48 hours. Observations in scanning and transmission electron microscopes revealed that plaque accumulated both in epoxy resin and hydroxyapatite areas of the splint surface. An extensive network of thread‐like structures connected the individual organisms to each other and to the underlying pellicle layer. This layer generally was somewhat thicker on the crystal surfaces than on the epoxy resin, possibly due to enhanced absorption of glycoproteins to the high energy surface of the hydroxyapatite crystals. Advantages of the splint method are: 1) Easy and rapid technique unrestricted by the presence of cavities or available teeth for extraction. 2) Plaque development may occur on hydroxyapatite surfaces which can be readily sectioned for transmission electron microscopy without decalcification. 3) Sequential colonization can be studied by removing segments of the splint at different time intervals.
Effect of inflammation on collateral circulation of the gingiva
Authors: Kennedy James E.
Published: July 2006

The effect of inflammation on collateral circulation of the gingiva and the vasculature of the periodontal ligament was studied in 12 squirrel monkeys. Gingival inflammation was induced by tying silk ligature at the cervical area of mandibular bicuspids and molars to encourage plaque accumulation. At 2, 10 and 26 weeks after ligature placement the animal's vasculature was perfused with India ink and calf serum. Nonligatured bicuspids and molars from the same animals served as controls. At all time points, on all experimental tooth surfaces examined, the vascularity (% grid intersections falling over vessel lumen) of the cervical portion of the periodontal ligament was significantly higher than the controls. The number of vessels connecting vessels of the periodontal ligament with supracrestal vessels was also significantly higher. There was a tendency for the number of vessels perforating either the alveolar bone proper or the alveolar crest to increase when inflammation was induced. The results of this study demonstrate the development of collateral circulation from the periodontal ligament to the gingiva in response to inflammation and help to explain the extension of inflammation into the deeper structures of the periodontium, including the periodontal ligament.
The effect of hyaluronidase upon epithelium in vitro
Authors: Innes P. B.
Published: July 2006

The effect of hyaluronidase on embryonic chicken skin and mouse oral mucosa has been studied in vitro. Autoradiographic studies showed that .05% hyaluronidase increased the epithelial mitotic index while liquid scintillation techniques demonstrated that hyaluronidase increased the uptake of tritiated thymidine in chicken skin in vitro. Further experiments demonstrated that .05% hyaluronidase interferes with the keratinization process in embryonic chicken skin and mouse oral mucosa in vitro.
Isocitric dehydrogenase activity in non–inflamed attached gingiva of rhesus monkeys
Authors: Bergquist J. J. , Organ R. , Nuki K.
Published: July 2006

Isocitric dehydrogenase activity was measured using ultramicrochemical techniques under optimum conditions in clinically non‐inflamed attached gingival tissue of Rhesus monkeys. Only gingivectomy specimens determined to be clinically non‐inflamed were used. Optimum assay conditions were determined in fresh gingival homogenates. Freeze‐dried sections were dissected into morphologically distinct fragments which ranged in weight from 14 to 240 nanograms (10−9 grams). Isocitric dehydrogenase activities were calculated for the various layers of epithelium, whole epithelium and connective tissue. Mean activities were reported in micromoles of substrate converted per gram of dry tissue weight per minute at 37°C. They were: surface layer 31.38, granular layer 30.97, spinous layer 29.17, basal layer 53.19, connective tissue 32.23 and whole epithelium 30.19. These results are compatible with, though somewhat higher than isocitric dehydrogenase activities reported in similar epithelial tissues, such as normal human and prosimian epidermis.
Insulin reversal of alloxan–diabetes induced changes in gingival collagen metabolism of the rat
Authors: Ramamurthy N. S. , Zebrowski E. J. , Golub L. M.
Published: July 2006

Adult, male Sprague‐Dawley rats were randomly divided into the following groups: control, control + insulin, alloxan‐diabetic, and diabetic + insulin. Diabetes was induced by a single dose of alloxan (200 mg/Kg body weight), administered i.p. in isotonic saline. Rats in the control + insulin group received 3 I.U. of insulin daily. The diabetic + insulin group were given sufficient insulin (3–5 I.U.) to maintain their urine glucose levels in a 0‐1/4 % range. Urinary glucose levels for each animal were determined daily. The animals were killed after 21 days and the fasting blood glucose concentration, serum and 24 hour urinary levels of hydroxyproline, gingival collagen and protein concentrations were determined. Collagenolytic activity of rat gingivae in tissue culture was also measured. The alloxan‐diabetic rats showed (1) a marked hyperglycemia and glycosuria, (2) decreased levels of water‐soluble protein and acid‐soluble collagen in gingivae, (3) an increased collagenase activity of gingival fragments in culture and (4) a marked increase in the serum concentration and urinary excretion of hydroxyproline. The administration of insulin to the diabetic rats partially or completely returned to normal levels each of the altered physiological parameters described above. These insulin sensitive changes appear, therefore, to have resulted from the diabetic condition of the rats rather than from any non‐diabetic effects of alloxan treatment. Similar changes in gingival collagen metabolism in humans, if present, could be related to the more rapid periodontal destruction observed in diabetic patients.
Absence of the localized Schwartzman reaction following 6‐OH dopamine sympathectomy
Authors: Shapiro L. , Cuevas P. , Stallard R. E. , Ruben M. P.
Published: June 2006

This investigation was undertaken to determine whether the presence of catechol amines was necessary for endotoxin to be operative in the production of a localized Schwartzman reaction. Seven rabbits were pretreated with 6–OH dopamine to produce a generalized chemical sympathectomy. An attempt was made to induce a localized Schwartzman reaction in these rabbits as well as in a control group. The rabbits in the experimental group did not develop the classical localized Schwartzman reaction, while those in the control group developed the localized Schwartzman reaction both clinically and histologically. The results of this present investigation indicate that catechol amines must be present for endotoxin to be operative in producing a localized Schwartzman reaction. A theory has been proposed for the possible relationship between catechol amines levels and endotoxin levels in the pathogenesis of the necrotizing gingivitis lesion.
Effect of anti‐thymocyte serum on chronic gingival inflammation in dogs
Authors: Nobréus Nils , Attström Rolf , Egelberg Jan
Published: June 2006

The role of cellular immunity in chronic gingivitis has been studied in beagle dogs. The mechanism of delayed hypersensitivity in the animals was suppressed by administration of rabbit anti‐dog‐thymocyte globulin (ATS). The immunosuppressive effect of the antiserum was evaluated from the inhibition of a delayed hypersensitivity reaction in the skin to l‐dinitro‐2.4‐chlorobenzene (DNCB). The level of gingival inflammation was determined before and after antiserum administration by measurements of crevicular leukocytes, gingival fluid and activity of acid phosphatase in crevicular samples.

Antiserum administration inhibited the hypersensitivity reactions in the skin towards DNCB. The gingival parameters were moderately reduced, but similar changes occurred in a group of control dogs injected with normal rabbit immunoglobulin. The results indicate that cellular immunity does not play a major role for the continuous maintenance of chronic gingivitis in the beagle dog.
Comparative metabolism of female sex steroids in normal and chronically inflamed gingiva of the dog
Authors: ElAttar T. M. A. , Hugoson A.
Published: July 2006

Normal and chronically inflamed gingival tissue of three beagle dogs were removed by means of gingivectomy for histological and biochemical studies on the in vitro metabolism of female sex steroids, progesterone and estrone. In normal gingiva no conversion of progesterone took place, while in the inflamed tissue 51974‐ and 51974‐pregnanediones were detected as the only conversion products. Esterone was converted to estradiol‐171974 in both normal and inflamed gingiva. The amount of estradiol‐171974 found in inflamed tissue was twice as much as that in the normal tissue. The increased conversion of female sex steroids in inflamed gingiva and the nature of their conversion products might be significant factors in the aggravation of gingival inflammation.
Effect of analogues of steroid and thyroxine hormones on wound healing in hamsters
Authors: Pirk Frederick W. , Elattar T. M. A. , Roth Genevieve D.
Published: July 2006

The effect of two anabolic hormones on wound healing was studied. Following the extraction of a lower first molar, ten normal hamsters received intraperitoneal injections of Durabolin, ten received Synthroid, and ten were given Durabolin and Synthroid. Ten controls received saline injections. Two animals from each group were sacrificed at 4, 8, 12, 16, and 20 days post extraction. Histological sections revealed the following changes: Animals treated with Durabolin exhibited fewer inflammatory cells, significant earlier bone fill and more accelerated reepithelization than the controls. The group receiving Synthroid produced bone replacement earlier than the controls. Epithelization occurred at essentially the same rate. When Durabolin and Synthroid were administered simultaneously, the animals demonstrated fewer inflammatory cells and less bone fill than the controls.
The formation of the vasculature of free gingiva in deciduous teeth of cats and dogs
Authors: Hock Janet
Published: July 2006

Vital microscopy, silicone rubber perfusion and histologic techniques were applied in a study of the development of the gingival vascular morphology in cats and dogs, during and following eruption of the deciduous canines and molars. It was found that vascular and histological events associated with the organisation of the capillaries in crestal gingiva predominated during the early stages of eruption. Vascular remodelling during the later stages of tooth eruption occurred in apical gingiva and was associated with apparent degeneration and loss of some vessels. A regular vascular network, comparable to that described by Hock and Nuki (1971), was found in all gingival specimens examined prior to the onset of clinical gingivitis.
Experimental allergic gingivitis
Authors: Sela J. , Ulmansky M. , Dishon T. , Rosenmann E. , Boss J. H.
Published: July 2006

One to eight injections of BSA or saline were given into the gingiva of sensitized or nonsensitized rats. The mucous membrane of untreated rats was found to be mildly inflamed. A single injection of BSA or saline caused moderate to severe gingivitis. The severity and incidence of gingivitis decreased with increasing number of injections of BSA or saline into the mucosa. This phenomenon of induced “local non‐reactivity” is similar to that observed in the parotid gland after multiple introductions of antigen.
A histochemical study of glycosidases in hydantoin induced hyperplastic, healthy and inflamed human gingiva
Authors: Larmas Liisi
Published: July 2006

Fresh samples of hydantoin induced hyperplastic, healthy and inflamed human gingiva were studied histochemically using various azo dyes for β‐glucuronidase (EC 3.2.1.31), for β‐ and β‐glucosidase (EC 3.2.1.20 and 3.2.1.21) as well as β‐galactosidase (EC 3.2.1.23) and for N‐acetylglucosaminidase (EC 3.2.1.30), in order to add support to the hypothesis that hydantoin induced hyperplasia is always connected with inflammation.

Moderate β‐glucuronidase activity was observed in healthy, inflamed and hydantoinhyperplastic gingiva. The distribution of the enzyme activity was similar in all types of the tissue except the stratum corneum. The healthy gingiva did not reveal this activity whereas the inflamed and hydantoinhyperplastic gingiva did. The stratum basale and spinosum of the epithelium, the fibroblasts and the inflammatory cells, especially the macrophages, revealed enzyme activity in all types of tissues. In the healthy tissue only a few inflammatory cells were seen and thus the β‐glucuronidase activity was low when compared to inflamed or hyperplastic gingiva.

Weak β‐galactosidase, N‐asetylglucosaminidase and β‐glucosidase activity was seen in all types of gingival samples. Enzyme activity was observed in the same structures as β‐glucuronidase with the exception of the stratum corneum, which revealed no activity.

The relatively strong β‐glucuronidase activity in the keratinized cell layer of the epithelium of inflamed and hydantoinhyperplastic tissue may be due to the microbial enzyme diffusion into the keratinized cell layer of the injured tissue.
The effect of various disclosants on plaque accumulation in human subjects
Authors: Goldman R. S. , Abelson D. C. , Mandel I. D. , Chilton N. W.
Published: July 2006

A clinical trial was designed to evaluate the effect of daily use of three disclosants, erythrosine, fast green and sodium fluorescein, compared to a saline control, on subsequent plaque deposition. Twenty subjects refrained from all oral hygiene for four consecutive 7 day periods. Each subject rinsed each night with a disclosing solution or saline as assigned and according to a design using 5 restricted Latin Squares of 4 subjects each.

At 7 day intervals, plaque score (modified Quigley‐Hein, J. Periodontology, 41:41, 1970), plaque weight and absorbance were evaluated and each subject received a rubber cup prophylaxis and another disclosant was assigned. The data revealed no significant differences between the groups of subjects using the various disclosants or saline, demonstrating that daily use of these agents has no effect on rates of plaque formation as determined clinically. There was a statistically significant increase in plaque accumulation (20 %) in all groups by completion of the experiment despite the weekly prophylaxis. All subjects had a moderate to severe gingivitis by the end of the fourth week.
Restricted latin square design in a plaque disclosant study
Authors: Varma A. A. O. , Fertig J. W. , Chilton N. W. , Mandel I. D.
Published: July 2006

Twenty subjects were used in a clinical trial of the effect of 3 disclosants (erythrosine, fast green, sodium fluorescein and normal saline) on plaque score, plaque weight and EDTA dispersion. Five 4×4 Latin Squares of a restricted type were employed, so that carryover effects can be estimated most efficiently. Each of the 20 subjects used each of the 4 test agents for a week at a time. The details of the design and of the statistical analysis are presented.

There were no significant carryover effects for any of the study solutions on plaque score, plaque weight or EDTA dispersion. The 4 disclosants did not differ significantly from each other in their effect on the 3 variables. In the case of plaque score, the fourth week gave significantly higher average values than the first three weeks. In the case of plaque weight, the values in the first week were significantly elevated.

The correlation coefficients between the 3 indices of plaque accumulation were only modest in size. The relatively low correlation between the 3 variables suggest that in a clinical trial the results with the 3 variables will not necessarily confirm each other.
Early formation of dental plaque on plastic films
Authors: Röunströum Anders , Attströum Rolf , Egelberg Jan
Published: June 2006

In human subjects with healthy gingiva thin transparent plastic films were applied to the buccal surfaces of premolars in the upper and lower jaws. The films were left in place for periods of 15, 30, 60, 120 and 240 minutes. The presence of coccoid bacteria, leukocytes and epithelial cells was investigated in an area adjacent to the gingival margin. The results showed that by 15 minutes coccoid bacteria had become attached to the artificial tooth surface. The number of microorganisms gradually increased during the time of the study. Large numbers of cocci and the formation of micro‐colonies were observed after 120 and 240 minutes. Increasing numbers of leukocytes and epithelial cells were also found during the period of observation.
Histopathologic features of the initial and early stages of experimental gingivitis in man
Authors: Payne WilliamA. , Page Roy C. , Ogilvie AlfredL. , Hall WalterB.
Published: July 2006

The pathologic alterations occurring in the gingival tissues of humans immediately following the beginning of plaque accumulation have not been elucidated previously. Seven males, 22–31 years of age, free of clinical manifestations of dental and periodontal disease, and exhibiting a Plaque Index score of zero for the previous 28 days served as subjects. Plaque control measures were discontinued for 8 days and biopsies, were taken from the buccal marginal gingiva of the first premolars on days 0, 2, 4, and 8. Paraffin‐ and Eponembedded sections, treated with a variety of histochemical stains were analyzed microscopically and cell counts were done on 1‐micron Epon sections. At 2 and 4 days following the beginning of plaque accumulation, the vessels subjacent to the junctional epithelium exhibited vasculitis and alterations in the perivascular collagen. There was a statistically significant increase in the number of neutrophils residing in the junctional epithelium. By the end of the 8‐day period, the number of small mononuclear cells, mostly lymphocytes, in the connective tissues had increased by 3‐fold and the area of collagen fiber alteration by 4‐fold. In addition, the number of fibroblasts per unit area of connective tissue decreased significantly. Thus, within the period of 8 days following the beginning of plaque accumulation, an early lesion exhibiting many features characteristic of delayed hypersensitivity develops.
Elevation of a serum component in periodontal disease capable of modulating chemotactic infiltration
Authors: Gothier Douglas E. , Richard Gaumer H. , Pihlstrom Bruce L. , Folke Lars E. A.
Published: July 2006

Serum from dental patients was examined for its capacity to affect migration of polymorphonuclear leukocytes toward a complement‐independent chemotactic factor, bacterial filtrate of Escherichia coli, (BF), Seven subjects with advanced periodontitis, documented with clinical measurements of pocket depth, loss of attachment, indices for gingival inflammation and oral hygiene, were paired with normal subjects of similar age and sex.

This study shows that patients whose only apparent clinical symptom was severe periodontal inflammation harbor a heat‐stable, serum component which neutralizes factors chemotactic for polymorphonuclear leukocytes. A role for this component in modulation of inflammatory infiltration is discussed.
In vitro cultivation of adult human gingiva
Authors: Mlinek A. , Buchner A.
Published: July 2006

The in vitro behavior of human gingiva was studied using a simple tissue culture technique. Gingival explants from adult patients undergoing periodontal surgery were cultivated in three different media for periods up to three weeks. It was demonstrated that primary epithelial cell cultures can be obtained under simple and predictable conditions. The migrating cells were compact and uniform in shape and resembled the spinous cell layer of a squamous stratified epithelium. Mitotic activity was regularly observed all over the outgrowth, which continued to grow throughout the entire experimental period.
The collagen content of skin and gingival tissues in ascorbic acid‐deficient monkeys
Authors: ØSstergaard E. , Löe Harald
Published: July 2006

Five green monkeys were used In this study. Three animals were fed a scorbutigenic diet and the remaining two served as controls. Biopsies were dissected from the vestibular gingiva and dorsal skin and polyvinyl sponges were implanted subcutaneously during 4 week periods throughout the experimental period. The animals were sacrificed after 12 weeks and the periodontal ligament was removed. Collagen extracts were prepared from the gingival and granulation tissues and treated with bacterial collagenase. Following acid hydrolysis the total amount of proline and hydroxyproline was determined in the various tissue preparations.

In the tissues examined, the content of hydroxyproline decreased in the scorbutic animals throughout the experimental period. The decrease in the hydroxyproline content of the gingiva started within the first 4 weeks and was faster than that of the skin, indicating that the extent of decrease is dependent of the turnover rate of the collagen in the tissues. The synthesis of hydroxyproline was almost totally impaired in the granulation tissue formed in the sponges implanted after the 8th week of experimentation. Collagenase treatment of collagen extracts resulted in a release of proline and hydroxyproline in a higher ratio in extracts from the experimental animals than in extracts from the controls. It is concluded that ascorbic acid is a prerequisite for the maintenance of the collagen pool in the tissues and that lack of this vitamin results in the formation of a collagenase degradable protein fraction with a low hydroxyproline content.
Afibrillar dental cementum in the rat and hamster
Authors: Listgraten M. A.
Published: June 2006

Afibrillar cementum “spurs” have been observed as a direct coronal extension of fibrillar root cementum near the cemento‐enamel junction of rat molars. It was also present as a localized deposit over the dentin surface of a hamster mandibular molar near the bifurcation. Adjacent cementicles in the periodontal ligament consisted of an intimate mixture of fibrillar and afibrillar cementum. It is suggested that afibrillar cementum may be due to failure of the collagen moiety to aggregate into fibrils or to a marked relative increase in the glycoproteoglycan content of the organic matrix.
Intracellular collagen fibrils in the periodontal ligament of man
Authors: Eley B. M. , Harrison J. D.
Published: June 2006

Periodontal ligament from 6 teeth extracted from patients was examined electron‐microscopically for the presence of intracellular collagen fibrils. These were occasionally found in fibroblasts in the tissue from 4 teeth, but were not otherwise seen.
A comparison of the glucose and protein content of gingival fluid from diabetics and nondiabetics
Authors: Ficara Anthony J. , Levin Marvin P. , Grower MarvinF. , Kramer George D.
Published: June 2006

The glucose and protein content of the gingival fluid and blood of 10 diabetic patients and 10 control subjects with gingival and plaque indices of 1–2 were compared. Both the control and diabetic groups had similar blood and gingival fluid protein levels as well as comparable gingival fluid volumes. The glucose content of both the gingival fluid and the blood of the diabetics was significantly elevated above those seen in the control group. The glucose content of the gingival fluid from the diabetics also showed a significant correlation to blood glucose levels found in each patient. The increased glucose content of the gingival fluid in diabetics may reflect metabolic changes in the gingival tissues as well as altered vascular permeability of the capillaries present in the gingival crevice.
Scanning electron microscopic study of human gingival epithelial cells on the surface of teeth and glass slides
Authors: Saglie Reinaldo , Johansen Jan R. , Tollefsen Tore
Published: July 2006

Scanning electron microscopy was used for a comparative study of gingival epithelial‐like cells grown on glass slides and epithelial remnants on extracted teeth. The micrographs showed that the shape, surface morphology, edges, intercellular contacts, light areas, and fibrous‐like products of the cells were quite similar. The method facilitated identification of epithelial cell remnants in the gingival pocket area of extracted teeth.
Antigens of Leptotrichia buccalis
Authors: Falkler William Alexander , Hawley Charles E.
Published: July 2006

A soluble antigen preparation (SALB), a water soluble lipopolysaccharide preparation, and a phenol soluble lipopolysaccharide preparation ofLeptotrichia buccaliswere used in a variety of serologic tests with human sera from periodontal patients. Sera from five of six periodontal patients reacted in hemolysis and indirect passive hemagglutination tests using SALB or water soluble lipopolysaccharide treated sheep red blood cells (SRBC). Only one of six individuals showed a titer to the phenol soluble lipopolysaccharide preparation in the same tests. The sera and antigens that gave positive results in the hemolysis test did not react in standard complement fixation or immunodiffusion tests. Using an indirect passive hemagglutination test with SALB treated tanned sheep red blood cells, five of six sera were again positive, however the titers were two to three fold lower. Adsorption of the SALB with SRBC removed the antigen reactive in the untanned cell test but had no effect on the antigen in the tanned cell test. On the basis of different antigen absorption characteristics to SRBC, these results suggest humans produce antibody reactive with both protein and lipopolysaccharide antigens ofL. buccalis.
Antigens of Leptotrichia buccalis
Authors: Hawley Charles E. , Falkler William Alexander
Published: July 2006

An ultrasonicate, a heat treated ultrasonicate, and a water soluble lipopolysaccharide preparation of Leptotrichia buccalis were used to sensitize sheep red blood cells. The sensitized cells were employed in a hemolysis test with guinea pig complement and the sera from human subjects undergoing therapy for periodontal disease. The tests revealed variable titers of hemolytic antibody in these patients to all antigens of L. buccalis studied. Hemolysis tests involving the use of Sephadex G‐200 immunoglobulin pools of the sera, anti‐μ heavy chain absorption of the sera, and the treatment of the sera with a sulfhydryl compound, ethanethiol, indicate that the antibody activity reactive with L. buccalis antigens seen in the hemolysis test is of the IgM class. An evaluation of the antigenic preparations used in the tests suggest that the hemolytic IgM activity is directed toward a lipopolysaccharide moiety of the organism. The finding of a complement fixing antibody in the sera of patients with periodontal disease to surface antigens of a normal resident of dental plaque is consistent with the concept of complex mediated immunopathology of periodontal disease.
Immunoradiometric assay for quantification of serum antibodies to dental plaque antigen in immunized dogs
Authors: Ahlstedt Staffan , Rylander Harald
Published: July 2006

An immunoradiometric assay (IRMA) was used for quantifying dog serum antibodies to antigens from dental plaque collected from full‐grown dogs. The antigens were adsorbed onto the inner surface of plastic tubes and then incubated with dog‐anti‐plaque serum. 125I‐labelled anti‐dog plasma‐immunoglobulin was used for quantification of the specific antibodies.

Four 10 months old Beagle dogs in excellent gingival health were immunized for 10 weeks with ultrasonicated dog dental plaque. The anibody levels in antisera sampled 6, 8, 10 and 11 weeks after the first antigen injection were 2 to 5 times as high as those recorded before the immunizing period.

The variability of the assay as judged from the difference between duplicate samples was found to be 18 %± 4 (p < 0.01) of the mean value and the variability between the same serum ran on different test occasions 13 %± 7 (p < 0.01). The specificity of the antigen‐antibody reaction in the immuno assay was tested by inhibition experiments, Preincubation of the antisera with dental plaque antigen significantly inhibited the antigen‐antibody reaction in the IRMA, while bovine serum albumin did not.
Plaque induced periodontal disease in beagle dogs
Authors: Lindhe Jan , Hamp Sven‐Erik , Löe Harald
Published: July 2006

The present investigation was carried out in order to study some aspects of the clinical, roentgenographical and histopathological alterations of periodontal tissues in dogs which during a 4‐year period were allowed freely to accumulate plaque.

Twenty inbred Beagle dogs, at the start of the study 10 months of age, were used. During a preparatory period of eight weeks the animals were once weekly subjected to a careful prophylaxis and had their teeth brushed twice daily. At the end of this period the dogs were divided into two groups of ten (test and control). From day zero of experimentation and onwards the teeth of the control dogs were twice daily subjected to meticulous toothbrushing, whereas the teeth of the test dogs were not cleaned. Examinations of the periodontal tissues were performed at days 0, 7, 14, 21, 28 and after 2, 4, 6, 8, 12, 18, 24, 36 and 48 months. Biopsies of different tooth regions were made on day zero and after 6, 12, 18, 24, 36 and 48 months of experiment. In the sections were measured (i) the distance from the cemento‐enamel junction (CEJ) to the most apical cells of the dento‐gingival epithelium, and (ii) the distance from CEJ to the level of the marginal alveolar bone.

The study demonstrated that it is possible in dogs to establish and maintain a normal gingiva simply by eliminating calculus and then subjecting the animals to daily repeated and carefully performed tooth cleanings. Dogs allowed freely to accumulate plaque rapidly developed signs of gingivitis and eventually also clinical, radiographical and histopathological signs of periodontal tissue breakdown. The observations show that at least one type of periodontal disease is induced by factors within the dental plaque.
Polymorphonuclear leukocyte chemotaxis in the absence of oxygen
Authors: Kraal J. H. , Kenney E. B.
Published: July 2006

Human polymorphonuclear leukocytes were tested for chemotactic migration in the Boyden Chamber system. The attracting agent was activated human plasma. Experiments were carried out in a strictly anaerobic environment in which all the suspensions assumed a very low redox potential. Control experiments were carried out in an aerobic environment. Chemotactic migration occurred equally well under both conditions.
Total viable count and differential count of vibrio (campylobacter) sputorum, fusobacterium nucleatum, selenomonas sputigena, bacteroides ochraceus and veillonella in the inflamed and non inflamed human gingival crevice
Authors: Van Palenstein Helderman W. H.
Published: July 2006

From 3 groups of individuals with non inflamed, slightly inflamed or moderately inflamed gingiva 3 to 4 paperpoint samples were taken from different buccal gingival crevices in each individual.

Samples were cultivated on a modified CBRCA medium which permitted the differential count of five groups of gram‐negative anaerobes. The total count per volume units was 9‐times higher in moderately inflamed than in non inflamed crevices. A significant increase in the proportion of Vibrio (Campylobacter) sputorum and Fusobacterium nucleatum occurred with inceasing gingival index score. Bacteroides ochraceus and Selenomonas sputigena, though present in low numbers also increased slightly. The proportion of Veillonella seemed independent of gingival index score. This added up to a significant increase in the proportion of cultivable gram‐negative organisms with increasing gingival index score.
The effect of endotoxin and human dental plaque on the respiratory rate of bone cells
Authors: Robinson P. J. , Shapiro I. M.
Published: June 2006

The effect of endotoxin and heat treat dental plaque on the respiratory activity of intact, viable bone cells was studied. cells were isolated from the zone of provisional calcification of chick epiphyseal plates. The mean rate of oxygen consumption was 20.7 × 10−9 per atom/min/cell. This was reduced by 36% in the presence of 0.1% endotoxin and by 16.1% when exposed to 0.1% heat treated dental plaque. The results suggest that endotoxin mediates bone resorption through stimulation of anaerobic metabolism.
In vitro cultivation of adult human gingiva
Authors: Buchner A. , Mlinek A.
Published: June 2006

Gingival tissue from adult patients undergoing periodontal surgery was used for in vitro cultivation. The explants were grown in three different media utilizing both tissue culture and organ culture techniques. Specimens were removed daily and processed for light and electron microscopic observation. The explants exhibited similar patterns with both culture techniques. Changes in the superficial epithelial layers were observed as early as 2 days after cultivation while the deeper spinous and basal cells maintained their integrity for as long as 5 days. Epithelial migration along the cut surface of the connective tissue resulted In complete encirclement of the explant followed by necrotic changes in the connective tissue.
Correlation between gingival fluid measurements and macroscopic and microscopic characteristics of gingival tissue
Authors: Daneshmand H. , BryanWade A.
Published: July 2006

Thirty interdental sites in 30 subjects having varying degrees of periodontal inflammatory disease were evaluated. A G.I. score was recorded, crevicular fluid collected and measured, pocket depths measured and biopsies undertaken. Two histological indices were developed, one based on the extent of inflammatory cell infiltration and epithelial breakdown (H.I.) the other on the number of extravasated inflammatory cells (I.C.I.). Low positive correlations of about the same strength (r = 0.3) were found between both histological indices and the G. I. and fluid measurements. No correlation at all was found between the histological index and pocket depth, but there was a slight correlation between the inflammatory cell index and the depth of the pockets. A moderate correlation was found between the amount of gingival fluid and G.I. scores. A low degree of correlation was found when the G.I. was compared with pocket depths. The strongest relationship was between the Histological Index and the Inflammatory Cell Index. It seems probable that different indices evaluate different aspects of the inflammatory response. In studies of small samples it may be wise to incorporate parameters which evaluate both macroscopic and microscopic characteristics as well as measurement of gingival fluid whenever practicable. For incidence and prevalence studies, however, a gingival index based on macroscopic criteria and measurements of pockets and loss of attachment are much simpler and quicker than the collection, staining and measurement of gingival fluid, whilst histological examination is usually impracticable.
The effect of alteration in the sulcular environment upon the movement of 14C‐diphenylhydantoin through rabbit sulcular tissues
Authors: Steinberg ArnoldD. , Steinberg June , Allen Pamela , Jeffay Henry
Published: July 2006

The kinetics of uptake and transport into blood after two hours of incubation of diphenylhydantoin (DPH) appears to be of the saturation type, (i.e. linear with the amount of DPH available for transport), but at higher DPH concentration the transport rate is markedly decreased. Insights into the properties of the transport system are gained by studying the effects of substances believed to alter cell membrane properties. The addition of 0.03 M potassium fluoride or 0.03 M sodium cyanide in gingival sulcus significantly alters the uptake of 14C‐DPH by serum. These findings and use of this methodology have important implications in the study of sulcular tissue physiology and pathology.