bluuebunny/crossref_metadata_2025 huggingface dataset:
Regeneration of surgically removed buccal alveolar bone in dogs
Authors: Nyman Sture , Karring Thorkild
Published: July 2006

The aim of the present study was to examine if the establishment of a new fibrous attachment to the root surfaces is accompanied by regeneration of surgically romoved buccal alveolar bone.

The experiments were carried out in two dogs with healthy periodontal conditions. The marginal 5–7 mm of the buccal alveolar bone between the mesial and distal line angles of each root of one maxillary second and one mandibular third premolar in both dogs was removed after elevation of a muco‐peristeal flap. During this procedure attempts were made to minimize the mechanica injury to the root cementum and the supraalveolar connective tissue attachment. A notch was prepared in the root surfaces at the level of teh surgically esablished bone crest. This notch served as a landmark for measurements to be made in histological sections. The flaps were repositioned and sutured with interrupted mattress sutures. During the entire experimental period, meticulous plaque control was maintained. In each dog. the contralateral teeth served as non‐treated controls. The animals were sacrificed 8 months after sugery and sections of all test‐and control areas prepared for light microscopic examination.

The results of the study demonstrated that in all experimental areas, new cementum formation and fibrous reattachment occurred in the supraalveolar area between the marginal bone crest and teh junctional epithlium. In only two out of eight test areas did the alveolar bone regenerate to or close ot the normal distance from the apical portion of the junctional epithelium whereas in the remaining six areas, a long supracrestal connective tissue attachment was present.
The structure and function of periodontal innervation
Authors: VAN Steenberghe D.
Published: July 2006

The histology of periodontal innervation in man and of the neural endings in the periodontal ligament in particular remains a controversial matter. Quantitative ultrastructural studies are needed and would help clarifying some functional characteristics of periodontal mechanoreceptors. Most of these characteristics are comparable to those of tegumental receptors elsewhere in the body. Some discrepancies exist however between the findings in perpheral afferent nerves and the findings in the intra‐crainal centres.

Concerning the functional significance of periodontal reeceptors, the jaw‐opening reflex and the silent period in jaw muscle activity are related to each other, and their importance is questioned. Although much work has been accomplished on the silent period, the concurrent monosynaptic reflex has been mostly neglected and it has not been demonstrated whether periodontal receptors are the only origin of these reflexes.

The perdominant role of periodontal receptors in detecting and discriminating forces acting on a tooth and in the control of the mandibular position when an occlusal contact is present has been proven.
Gingival matrix proteins
Authors: Dabbous M. Kh. , Seif M , Brinkley Sister B , Butler T , Braswell C. W.
Published: July 2006

Most of bovine gingival collagen is insoluble. CNBr treatment cleaved 85% of the insoluble material as soluble collagen peptides. Characterization of the CNBr peptides showed that gingival collagen is composed mainly of Types I and III in a ratio of 6:1 An additiona fraction, composed mainly of noncollagenous protein components (NCP) rich in acidic, hydroxy‐ and hydrophobic amino acids, accounted for approximately 15% of the insoluble matrix.
Studies on the relative binding affinities of chlorhexidine analogs to cationexchange surfaces
Authors: Slee Andrew M. , Tanzer Jason M.
Published: July 2006

An in vitro model system was employed ot dtermine the relative binding affinities fo a series fo sixteen chlorhexidine analogs to acidic funcitonal groups similar to those which are abundan in the oral cavity. The chlorhexidine analogs displayd a range ofbindign affinities and were dispalced subsequent ot binding from caboxylate and phosphonate substituted resins, although not from sulphnate substituted resins, by divalent cations or by saliva‐like divalent cation‐rich solutions. The agent were not displaced from such surfaces by monovalent cations there appears to be no correlation between the relative binding affinities fo agents to anionic groups and their previously observed in vitro antiplaque potencies.
Mitosis in epithelium of murine palatal mucosa in vivo and in vitro
Authors: Luke D. A.
Published: July 2006

Colchicine‐arrested metapheses were accumulated at half‐hourly intervals over a period of 5 hours in the palatal epithelium of adult male mice. From the rate of entry into mitosis, which was reasonably rectilinear, the mean cell cycle time of the basal layer in vivo was found to be 80.6 h and the duration of mitosis 1.4 h. When a similar accumulation of arrested metaphases was attempted over a period of 4 hours in palatal epithelium in vitro, the rate of entry into mitosis was not rectilinear and the mitotic activity was much lower than in vivo. It is concluded that this in vitro technique is not satisfactory for determining cell cycle characteristics in oral epithelium of the living animal.
Toothbrushing behaviour in relation to plaque and gingivitis in adolescent schoolchildren
Authors: Rugg‐Gunn A. J. , Macgregor I. D. M. , Edgar W. M. , Ferguson M. W.
Published: July 2006

Fifty seven 13‐year‐old children were asked to brush their teeth and were unaware that they were recorded on video tape. Gingival inflammation was measured (G.I.) before brushing and plaque levels (PI.I) after brushing. By viewing the films, each of 12 areas of the mouth were recorded as brushed or not brushed, together with the type and nummer of stokes used. For each area, plaque and gingivitis levels were related to the type of strokes used. The results showed the inability of these uninstructed adolescents to remove plaque, despite brushing for a mean time of 51s. For all of the areas no one stroke was consistently related to less plaque. In 3 out of the 4 buccal areas where the circular stroke was used, it was associated with the least plaque; in the remaining 2 buccal areas the long horizontal was associated with the least plaque. The relationship between gingival inflammation and brushing stoke mirrored that between plaque levels and brushing stroke.
The relationship between gingival inflammation and resistance to probe penetration
Authors: Robinson P. J. , Vitek R. M.
Published: July 2006

The present investigation was carried out to determine the location of the periodontal probe tip when various loads are applied. Additionally, the role of gingival inflammation to probe resistance was evaluated.

The sample consisted of 51 teeth scheduled for extraction. The Gingival Index (GI) was used to establish the degree of inflammation. A loading of 20,25,30 ponds was delivered by a spring loaded sleeve bearing probe fitted with a michigan 0 probe having a terminal diameter of 0.35 mm. The extracted teeth were fixed and then stained with 4% toluidine blue. Using a coronal reference groove and the apical margin of the connective tissue attachment (CTA) as reference points apical penetrtion of the probe was established.

The results of this study indicate that there is a linear relationship between the GI and the resistance of the gingival tissues to probe penetration. This is most apparent between a GI = 0 amd GI = 3. Wjereas with 30 ponds the mean penetration at GI = 0 was 0.30 mm. coronal to the CTA, the mean penetration was 1.25 mm apical to the CTA at GI = 3.
Evidence suggesting the presence of antigen‐antibody complexes on the surface of salivary leukocytes
Authors: Sonis S. T. , Mirando D. M. , Lamster I. B. , Stelos P , Wilson R.E.
Published: July 2006

Fc receptors of salivary leukocytes were studied in twelve patients using sheep red blood cell rosetting techniques. The number of salivary leukocytes having funcitonal Fc receptors was less than expected and was thought to be due to the presence of antigen‐antibody complexes on the surface of leukocytes.

Since immune complexes are known activators of neutrophils, we hypothesized taht glucose metabolism in the hexose monophosphate shunt by salivary neutrophils should be greater than a comparable cell population from peripheral blood. Using an assay to assess the metanolism of 14c‐labeled glucose, it was found that salivary leukocytes were more active than peripheral blood leukocytes and that the ability of salivary leukocytes to be extrinsically activated was less than peripheral blood leukocytes. The data suggests that immune complexes area probably present on the surface fo salivary leukocytes and that such complexes are able to modify the surface receptors and functional capacity of these cells.
Effects of repeated scaling and root planing and/or controlled oral hygiene on the periodontal attachment level and pocket depth in beagle dogs
Authors: Morrison E. C. , Lang N. P. , Löe H. , Ramfjord S. P.
Published: July 2006

This study was performed to evaluate the effect of initial and/or repeated subgingival scaling with or without controlled oral hygiene on the level of periodontal attachment and pocket depth in Beagle dogs. furthermore, the effect of repeated scaling on the progression of naturally developed periodontitis was to be determined.

At baseline, and at 1,6,12,24 and 36 months clinical parameters for plaquen deposits (PII), calculus (CI), gingival health (GI) periodontal attachment from the cementoenamel junction (CEJ) and pocket depth were recorded by the same examiner.

Eight healthy Beagles, 3 1/2–6 years of age with moderate naturally developed periodontal desease were divided into experimental and control animals. In the experimental group, 4 dogs received a thorough scaling and root planing at the start of the experiment. thereafter the experimental dogs were subjected to daily toothbrushing and a rubber cup and pumice prophylaxis every two weeks. The remaining 4 control dogs were not subjected to any oral hygience measures.

Two quadrants diagonally opposed in each animal (experimentaal and control) were scaled and root planed every six months.

In the experimental group a significant increase in attachment level was maintained throughout the study. Initial scaling followed by oral hygiene reduced pocket depth singificantly and pocket reduction was maintained over the three year period. Repeated scaling did not influence the mainternance of the attachment level or the reduction in pocket depth in the experimental group. The control animals continued to lose attachment and pocket depth increased during the study. Scaling every six months without oral hygience resulted in loss of attachment and increase in pocket depth, although the rate of attachment loss was retarded.

It is concluded that following initial scaling conticuous removal of bacterial plaque is essential for the maintenance of periodontal attachment. In moderate periodontal disease the levels of attachments may be maintained without surgical therapy.
Oral hygiene status of dental students as related to their personal and academic profiles
Authors: Bakdash M. Basher , Proshek John M.
Published: July 2006

This paper studied the correlation among a number of personal, pre‐dental and dental academic variables and sutdent's own personal oral hygiene. Oral hygiene status of 127 second year dental student was meadured accouding to O'Leary, Drake and Naylor (1972). The overall mean plaque score was 46.7% . Only 18.8 % of the students had excellent and good oral hygiene, while 63% of them had poor and very poororal hygiene. There were negative relationships approaching significance between the plaque score of students and their first year dental grade point avderage and second year dental grade point average. A significant negative correlation was observed between plaque score and test scores in Periodontology I. Students who had a better oral hyginene status tended ot obtain higher grades in periodontology I An analysis of the variance for the mean of each of the eleven variables as classified by oral hygiene status was performed. In general, students with better oral hygiene tended to achieve significantly gigher test scores than those students with less favorable oral hygiene in at least seven of the stated academic variables.
Improvements of in vitro cell‐material adhesion measurements
Authors: Fletcher Ronald D. , Adamiak John K. , Labant Maryann C. , Abertson John N.
Published: July 2006

The in vitro measurement of gingival cell‐bacto agar substratum adhesive‐bonding strength (γa) is described as it relates to cell‐ concentration, cell‐substratum contact time and serum concentration. These three factors are critical in obtaining reprocible γa's for gingival cell‐test substratum interactions.

Cell concentrations of less than 35 × 103 cells per cm2 gave low γa's (70–75 ergs/cm2) whereas 90–130 × 103 cells/cm2 resulted in γa's of 109–119 ergs/cm2, respectively. Maximum γa's (123 ergs/cm2) resulted after the cells had been in contact with the agar substratum for 24 hours. The adhesive‐bonding strenth after eight housrs of contact time, however, was not statistically different from the 24 housr readings and has the advantage of decreasing the test duration. Serum, and important factor for optimum adhesion measurements, produced a peak γa at the 10 % concentration.
The complementary structure of the superficial and deep surfaces of the cells lof the stratum corneum of the hard palate in the rat
Authors: McMillan M. D.
Published: July 2006

The supeerficial and deep surfaces of the cells of the stratum corneum from the hard palate of the rat were examined in the scanning electron mictroscope. The appearances were compared with those seen in thin sections. In the scanning electron microscope, the superficial surface of each epithelial cell, whether it was situated on the exposed surface or more deepley within the epithelium, had a honeycomb surface pattern of inteerconnecting ridges surrounding depressions. Lateral cell boundaries consisted of two ridges separated by a gap, and the imprints of the edges of the overlying cells were formed by single raised ridges which crossed on to adjacent cells. The deep surface of the cells was covered by microvilli, a deepo groove separated teh margins of adjacent cells, and the imprints of the cell boundaries of the underlying cells were formed by shallower grooves which also crossed on to adjacet cells, The sectionaal appearance of the stratum corneum, as seen in the transmissison electron microscope, confirmed that the cells at different levels overlapped. It also confirmed that the microvilli and grooves on teh deepo surface of the cells were truly complementary and intimately related to the depressions and ridges on the superficial surfaces of opposing cells.
The metabolism of proteoglycans and glycosaminoglycans in inflamed human gingiva
Authors: Embery G. , Oliver W. M. , Stanbury J. B.
Published: July 2006

Glycosaminoglycan (GAG)and proteoglycans (PG)were extracted from both relatively uninflamed and severely inflamed human gingiva. The constituent GAG, Hyaluronic acid, dermatan sulphate and chondroitin 4′ sulphate, were present in the same total amount and porportions in both tissues. In contrast the PG underwent substantial breakdown in the serverly inflamed tissue as judged by anion exchange chromatography and cellulose acetate electophoresis. The findings indicate theat whereas the GAG remain apparently unchanged during inflammation, the protein moiety of the PG is catabolised leading to a loss of structural integrity.
Periodontal repair after reduction o inflammation
Authors: Polson Alan M. , Kantor Michael E. , Zander Helmut A.
Published: July 2006

The purpose of this study was to clarify the relationship between alveolar bone repair and level of connective tissue attachment after reduction of inflammation in an experimental marginal periodontitis. Perodontitis was induced by tying plaque retentive silk ligatures around the mandibular second and third bicuspids in four squirrel monkeys. Ten weeks later the ligatures were removed. An oral hygiene regime of mechanical claning was started and continued three times a week for ten weeks. Induction of perodontitis around the same teeth of the contralateral side (control) of the jaw was timed so that the interproximal perodontium corresponded to the situation immediately prior to ligature removal. The coronal interproximal perodontium between the bicuspids was histometrically analyzed for level of connective tissue attachment, location of crestal alveolar bone, percentage of infiltrated supracrestal connective tissue. Before reduction of inflammation, apporximately 70% of the supracrestal connective tissue was infiltrated After oral hygiend, the infiltrate was loclized adjacent to the epithlium and occupied 20% of the connective tissue. Although the supracrestal connective tissue became organized, there was no coronal gain of connective tissue attachemnt and long junctional epithlia were present. However, singnificant bone repair occurred which increased bone volume and reduced periodoantal ligament width. Mechanism of bone resorption and reapair in periodontitis are discussed.
Cytoplasmic polarization of periodontal ligament fibroblasts
Authors: Garant Philias R. , Cho Moon‐Il
Published: July 2006

The fibroblasts of the periodontal ligament and especially those of the transseptal ligament are characteristically elongated with their long axes parallel to the principal fiber bundles. Their cytoplasmic orgamelles are polarized suggesting that secretory products are released from one end of the cell. The nucleus occupies the anterior pole of the cell. Cytoplasmic processes or lobopodia, containing numerous cytoplasmic filaments, extend from the anterior pole of the cell. The Golgi complex is situated in a large area of the cell between the nucleus and the distal end of the cell. Granular endoplasmic reticulum, mitochondria and numerous small vesicles are dispersed throughout most part of the cell. Intracellular collagen, akthough present in many areas of the cell, appears to be most abundant in the distal parts of the cell. Administration of colchicine in vivo, blocked collagen secretion and dereased cell elongation and polartity.

Results of and analysis of the orientation and polarization of the fibroblasts in the periodontal tissues appear to support the concept that these cells undergo active migration in vivo along existing substrata and that migration may be coupled to collagen secretion.
Autoradiographic evidence of the coordinaion of the genesis of Sharpey'a fibers with new bone formation in the periodontium of the mouse
Authors: Garant Philias R. , Cho Moon‐Il
Published: July 2006

Multiple injections of 3H‐proline over a period of ten days produced a series of radiolabelled appositional bands at sites of new bone formation. Appositional surfaces of periodontal alveolar bone not only contained parallel appositional bands but also a second series of bands oriented perpendicular to the appositional bands. The perpendicular bands were continuous with Sharpey's fibers of the adjacent periodontal ligament (PDL). Labelling over Sharpey's fibers frequently extended beyond the osteoblasts and into the PDL. This pattern of 3H‐Proline labelling suggests that new Sharpey's fiber are secreted simultaneouly with new bone deposition. The shape and polarity of adjacent PDL fibroblasts suggests that they may migrate away from the bone surface as they engage in Sharpey's fiber formation.
The in vitro differentiation of cat sulcular epithelium
Authors: Innes P.B.
Published: July 2006

The in vitro defferentiation of the sulcular epithelium from cats was studied. Gingival tissues were removed from the labial aspect of the canine teeth of 6 adult cats. These specimens were cultured on stainless steel rafts in organ culture dishes for 3 days. At the end of this period the specimens were examined in the light and electron mecroscopes. It was found that the sulcular epithelium, which at the time of explantation was a nonkeratinized epithelium, developed into a keratinized stratified squamous epithelium afer 3 days in vitro.

The results demontrated that sulcular epithelium possesses the potential to keratinize and it is suggested the that enviornmental factors are important in the in vivo differentiatio of this tissue.
Ultrastructural histochemistry of the dento‐epithelial junction
Authors: Kobayashi Kenichi , Rose George G.
Published: July 2006

Dento‐epithelial junctions (DEJ) of Rhesus monkeys were examined by electron microscopy after staining of for protein by the chloramine T‐silver methenamine (CT‐silger) technique. The dental cuticle characteristically reacted positively in contrast to the negative response of the basal lamina and therefore was regarded as a layer of highly condensedprotein. Degestion with the proteolytic enzymes, trypsin and protease resulted in a complete elimination of the dental cuticle material from the thin sections and thus confirked their proteinaceous nature demonstrated with the CT‐silver reaction to the CT‐silver stain.
Chemotaxis and vascular permeability produced by human periodontopathic bacteria
Authors: Lindhe J. , Socransky S. S.
Published: July 2006

The present investigation was carried out in an attempt to assess the chemotactic and vascular permeability inducing potential of some microorganisms which have been associated with gingivitis, advanced periodontitis and periodontosis. The four microorganisms studied in the present experiment, T. denticola, A. viscosus, B. melaninogenicus. and C. ochraceus were isolated from human periodontal disease. Bacterial samples were removed by means ofan oxygen‐free gas flushed syringe from specific sites within gingival pockets of humans displaying sings of varying degrees of gingivitis, rapidly advancing periodontitis or periodontosis. The bacterial cells were harvested from respective growth media by centrifugation, washed and sonicated. After lysis the resulting suspension was lyophilized, Prior to test the different lyophilized sonicates were dissolved in saline and the protein concentration of the solutions adjusted to 10 ug/ml. The chemotactic activity elaborated by the different bacterials test materials was studied by an in vitro technique originally described by Boyden (1962). Measurements of vascular exudation were performed in wound chambers implanted subcutaneously in the black of rats. The demonstrated that preparations obtained from microorganisms present in human dental plaques contain components which are chemotactic for neutrophil leukocytes and are capable of inducing or mediating increased vascular leakage in a granulation tissue. Material from Capnocytophaga ochraceus in comparison to substances from T. denticola, A. viscosus and B. melaninogenicus proved to be rather inactive in promoting neutrophil neutrophil chemotaxis and vascular exudation.
Pathological changes caused by the injection of lipids isolated from Gram‐positive organisms into the gingiva of rats
Authors: Irving J. T. , Heeley J. D. , Amdur B. H. , Socransky S. S.
Published: July 2006

Extractable lipids from Actinomyces naeslundii, strain I, and streptococcus mutans (6715) were injected in the oral mucosa of weanling rats. Whole lipid, neutral lipid, glycolipid and phospholipid fractions were compared with synthetic tripalmitolein. The animals were sacrificed at intervals, 6 hours to 14 days, and the tissues examined histologically.

Lipids from A. naeslundii resulted in an initial polymorphonuclear response, gradually replaced by lymphocytes with time. Effects on the underlying alvolar bone included disaaperance of osteoblasts, empty osteocyte lacunae, and in a few cases, bone resorption. An accumulation offibrillar debris was also seen as early as 18 hours, persisiting up to 96 hours. post‐injection.

Lipids from S. mutans resulted in a marked lymphocyte infiltration preceded by a very slight PMN response, similr changes in underlying bone, and no evidence of fribrillar debris. Recovery of osteoblasts along the underlying bone was slowest with the phospholipid fractions and fastest with neutral lipids seeming to correlate with their respective toxicity. The cell reaction to synthetic triplamitolien was similar to that elicited with the neutral lipid fractions but of shorter duration. In this system lipids from A. naeslundii were apparently more toxic than those from S. mutans.
A microbiological study of dental calculus
Authors: Sidaway D. A.
Published: July 2006

Deposits obtained from the in vitro calcificaqtion of vialble adn formalin killed microorganisms have been examined by Von Kossa staining and X‐ray diffraction analysis. 34 of the 35 species examined were isolated from, and represcented, the flora of human calculus.

Twenty‐one of the viable and 23 of the formalin‐killed cultures gave positive Von Kossa smears but idebntical results for live and dead preparations were obtained in only 25 of the 35 organisms examined. In viable cultres only, teh proportion of calcified organisms increased with time suggesting that degenrative change is probably a prerequistie for cellular calcification.

The X‐ray diffraction analysis shwed that in clacified viable cultures hydroxyapatitie was always found (22) and in the majority of cases (18) was the sole from of crystalline with octocalcium phosphate and/or brushite (10), gave a weaker pattern than that given by similar viable cultures.

In 9 deposits octocalcium phosphate and brushite were the only form s of calcium phosphate detected adn 6 of these gave positive Von Koss smears. The formation in vitro of these two forms suggests that, as previously recorded for hydroxyapatiti, the plaque microbiota may play a part in theri in vivo formation.
Leucocyte respones in the gingival crevice of the diabetic rat
Authors: Ramamurthy N. S. , Siegel M. , Iacono V. J. , Golub L. M.
Published: July 2006

Leucocyte chemotactic activity and the response of neutorphils, monocytes and lymphocytes in the gingival sulcus to surgery (during wound healing) was assesse in normal and alloxan diabetic rats. Before survery, the sulcular washes of both groups contained similar mubers of cell. One day post‐sugery, the normal sulci showed a marked increase in leucocytes due primarily to the presence of large numbers of neutrophis. Rapidly there after the leucocyte count decreased and approximated time 0 levels. The diabetic sulcus showed a 50% less intense reponse 1 day after sugery and a slower return to preopertive levels. The altered leucocyted response in the diabetic sulcus could reflect impaired chemotiactic activity, which was observed for periotoneal leucocytes, or other cellular or tissue abnormlities (eg. thickened basement membranes) that impede cell migration. Alloxan diabtes provides another model to study the relationship between lecocyte dysfunction and accelerated periodontal breakdwon.
Collagen phagocytosis by stimulated mouse periotoneal macrophages in vitro
Authors: Deporter D. A.
Published: July 2006

Thioglycollage‐stimulated mouse periotoneal macrophages were cultured in the presence of minced rat tail tendon collagen fibrils. Electron microscopic examination of the cultures after 24 hours revealed phagocytosis and intracellular degradation of collagen within phagocytic vacuoles. This ability of macrophages to phagocytose collagen may be an important mechanism in the destruction of collagen that occurs during chronic inflammation.
Comparative ultrastructure of Bacteroides melaninogenicus subspecies
Authors: Listgarten Max A , Lai Chern‐Hsiund
Published: July 2006

A total of 10 strains of Bacteroides melaninogenicus subspecies were examined by transmission electron kicroscopy after conventional processing, and staining with uranyl acetate and lead citrate. All strains examined had a cell periphery with a basic ultrastructure typical of that reprted for other Gram‐negative bacteria. However, only s.s. asaccharolytucus strins exhibited a moderately electron‐dense covering layer, 16–19 nm thick, in contact with the outer membrane of the cell wall, and numerous intercellular membranous vesicles. S.s. melaninogenicus strains, in contrast to those of those of other subspecies, had no extramural structures, and exhibited a distinct, intercellular, fibrillar matrix. S.s. intermedius cells featured a 9–14 nm thick, electron‐dense extramural layer which was separated by an electron‐lucent layer of similar thickness from the outer membrane of the wall. these morphological differences may be useful in differentiating these subspecies from one another. phological differences may be useful in differentiating these subspecies from one another.
Alkyl‐bisbiguanides as in vitro inhibitors of bacterial growth and dental plaque formation
Authors: Baker P.J. , Coburn R.A. , Genco R.J. , Evans R.T.
Published: July 2006

Nine anllogues of chlorhexidine, including Alexidine, in which the p‐chloroophenyl group had bneen replaced by straight or branched alkyl chains were found to be substantive ot saliva coated enamel. These alkyl bisbiguanides were also found to be antimicrobial in a tube dilution assay and tn prevent the formation of plaque in an in vitro plaque assay. Each of these compounds was found to be equal to or greater than chlorhexidine in antimicrobial or plaque inhibition activity against the periodontal organisms, Actinomyces viscosus and A. naeslundii. Against the cariogenic organism, Streptococcus mutans, each of these compounds was active but none had more active than several of the other analogues.
Connective tissue regeneration to periodontally diseased teeth
Authors: Cole R. T. , Crigger M. , Bogle G. , Egelberg J. , Selvig K. A.
Published: July 2006

A study was made to investigate the biological principle of new attachment of connective tissue to periodontally diseased root surfaces utilizing the previous finding that topical application of citric acid to the affected area may stimulate periodontal regeneration. Reconstructive surgery was performed on ten surfaces of nine teeth involved in advanced chronic periodontal disease. A muco‐periosteal flap was raised and the apical extent of existing subgingival calculus was demarcated by a notch made through the calculus and into the root. Following thorough instrumentation, a saturated solution of citric acid was applied to the root surface for five minutes and the flap repositioned and sutured. Four months later the teeth with attached periodontal tissues were removed and processed for histological analysis. Connective tissue regeneration characterized by deposition of new cementum, and more coronally, by tightly apposed soft connective tissue had occurred in all specimens. The junctional epithelium ended 1.2–2.6 mm coronal to the apical border of the notch in the various specimens. The results demonstrate that regeneration of periodontal tissues to a root surface that has become denuded as a result of chronic, destructive periodontal disease and that has been covered by calculus is, in fact, a biological possibility. This study does not establish whether or not acid conditioning of the root surface is a prerequisite for new attachment.
Preliminary characterization of material eluted from the roots of periodontally diseased teeth
Authors: Fine D. H. , Morris M. L. , Tabak L. , Cole J. D.
Published: July 2006

Eighteen periodontally diseased teeth and eleven normal teeth requiring surgical removal were each treated with one of four different solutions to elute potentially toxic material from their root surfaces. The solutions used were pyrogen‐free water, phenol‐water, trichloroacetic acid and citric acid. To define the composition of the eluted material, samples were analyzed for calcium, for ketodeoxyoctonic acid (KDO), a carbohydrate unique to Gram‐negative bacteria, and for limulus lysate activity. Limulus‐positive material was then analyzed for protein and nucleic acids and subjected to heat treatment, to the enzymes RNAse A and T1, and to lysozyme.

It was found that TCA and citric acid removed more calcium and more toxic material from the root surface and subsurface than did either water or phenol‐water.

The material extracted from 13 of the 18 diseased roots was limulus‐positive. Four of the limulus‐positive samples were also KDO‐positive, strongly indicating the presence of endotoxin in these samples. Neither these nor any of the other limulus‐positive responses were reversed or significantly reduced by exposure of samples to heat, to RNAse A and T1, or to lysozyme. In addition, limulus‐positive responses were unrelated to the amounts of protein and nucleic acids in the extracted material.

When considered together, these preliminary characterizations indicate the presence of endotoxin in the material eluted from periodontally diseased teeth.
Migration and division of progenitor cell populations in periodontal ligament after wounding
Authors: Gould T. R. L. , Melcher A. H. , Brunette D. M.
Published: July 2006

Connective tissue cells responding to wounding of the periodontal ligament of the lower first molar in mice were studied using the techniques of radioautography and grain counting. Animals were given an intraperitoneal injection of 2 uCi 1g 3H‐Tdr 1 hr before being killed at either 30, 72 or 120 hr after wounding. The ligament in 1 um plastic sections was divided into compartments on the basis of distance from the wound, and the relative number of labelled cells in each compartment was assessed at 30, 72 and 120 hours after wounding. The distance of each labelled cell from the closest blood vessel was also measured at each time to detect relative movement of labelled cells away from blood vessels. In a Parallel experiment, haematogenous progenitors of macrophages were depleted by irradiating the animals with 800rads prior to woundilng to determine if mistakes in identification between fibroblasts and marophages could significantly affect the results. The ultrastructural characteristics of 150 of the 3H‐Tdr labelled cells was examined in thin sections of wounded periodontal ligament prepared for elctron microcope radioautography, The majority of cells lebelled 30 hours after wounding were confirmed to be paravascular, and most of them were found to be located within 200 μ of the wound margin. Some of these cells appreared to have divided a number of times between 30 and 72 hours after wounding, and to have migrated into the wound between 70 and 120 hours after wounding. Examination of the irradiated material and the electron microscope radio‐autographs suggested that significant numbers of macrophages had not been included in the counts of labelled cells. The elctron microscope radioautographs also suggested that cells which exhibited different degrees of cytodifferentiation had incorporated 3H‐Tdr.
A study of the reformation of severed gingival fibers in aging mice using 3H‐proline autoradiography
Authors: Tonna Edgar A. , Stahl Sigmund S. , Asiedu Stephen
Published: July 2006

The present study monitored the healing responses at sites of attached but severed gingival fibers by following matrix production and turnover using 3H‐proline in mice of different ages. Fifty‐six BNL short‐lived mice of mixed sex to 78‐week‐old were used. A vertical gingival incision was made at the mesial papilla of the right maxillary first molar to the alveolar bone crest severing the gingival fibers. The left side was used as a control. Periodontal regions adjacent to the incision and some distance from the incision were studied. All mice were given a s.q. dose of 2μCi of 3H‐proline/gm. b. wt. and killed from 1 to 90 days later. Autoradiographs were prepared from routinely processed histologic sections for grain counting. The control crestal region exhibited the greatest matrical turnover of all sites tested regardless of age. With increasing age, however, the rates of uptake and turnover were significantly reduced in all regions. Post‐injury, additional peaks of activity occurred in young mice. In old mice, the injured cemental side exhibited significant uptake and prolonged matrical turnover. It was concluded that the matrix on the injured corium side was the most stable, while the cemental region was the least stable. Aging did not impede the tissue response to injury but increased the long term response.
Human gingival fibroblast cell lines in vitro
Authors: Rose George G. , Yajima Toshihiko , Mahan Charles J.
Published: July 2006

Eight human gingival fibroblast cell lines were cultivated on bovine collagen fibrillar mats thinly coated on over slips of tissue culture chambers. The responses of the cells to the collagen were studied by light and electron microscopy. It was shown that the collagenolysis was regional, occurring only in the immediate areas of the cells and resulted from the phagocytosis of collagen fibrils by the fibroblasts. There was no evidence by electron microscopy of an enzymatic lysis of the fibrils in the extracellular spaces. The fibrils were first seen within folds of the fibroblasts whose membranes contained multiple profiles of invaginating pinocytotic and/or membrane‐coated vesicles. The fibrils were then interiorized in slender cell processes and ultimately became enclosed within developing acid phsphatase positive lysosome‐like bodies. The process of phagocytosis and the sequences of development of the lysosomal enclosures are combined with the concept of “hydrolase secretion and recapture‐mediated endocytosis by fibroblasts” to derive a hypothesis for fibroblastic degradatin of cllagen.
Electron microscopic study of the regeneration of cementum and periodontal connective tissue attachment in the cat
Authors: Nalbandian John , Frank Robert M.
Published: July 2006

Regeneration of periodontal connective tissue attachment was studied at the ultrastructural level in cats following the removal of cementum and superficial dentin through a surgically created fenestration in the facial alveolar plate. Non‐decalcified specimens were examined 33, 45, 70, and 105 days after surgery. In early stages of healing, fibroblasts were aligned parallel, and immediately adjacent, to the cut, irregular dentin surface; subsequently, collagenous matrix formation was observed at this site. Some regions of the defects showed surface demineralization and extension of collagen into dentinal tubules. The first indication of cementum mineralization was the deposition of small crystallites along the irregularities of the dentin surface. After further development, a well‐defined zone containing c1osel packed crystallites was usually evident at the new dentin‐cementum junction. Peripheral to this, collagen orientation in the calcified cementum was primarily parallel to the tooth surface, with some perpendicular orientation suggestive of Sharpey's fiber formation. Collagen‐mineral patterns typical of the normal cementum surface were observed, and cementoblasts were seen in various stages of inclusion into the calcified matrix. Where the injury had not reached the dentin, collagen fibrils of new and old cementum were interwoven, and the junctional region demonstrated incomplete mineralization.
The concentration of proteins in human gingival crevicular fluid
Authors: Haitinoh J. , Ho E.
Published: July 2006

The amount and concentration of protein present in fluid obtained from individual healthy and inflamed gingival crevices have been examined. It was found that an artefactual hyperbolic relationship existed between protein concentration and fluid volume in fluid originating from healthy crevices, resulting in over‐estimation of protein content. In fluid originating from inflamed crevices, no statistically significant correlation existed between protein concentration and fluid volume, which is to be expected for an inflammatory exudate. The fluid dynamics of the crevicular region is therefore probably similar to that of the rest of the body.
Comparative analysis of gingival fluid and plasma by crossed immunoelectrophoresis
Authors: Tollefsen T. , Saltvedt E.
Published: July 2006

Samples of gingival fluid and plasma were taken from ten patients with varying severity of periodontal disease. Group I comprised seven patients with abundant plaque. Their mean pocket depth at the sampling sites was 5.6 ± 1.27 mm. Group II consisted of three patients with minimal plaque and a mean pocket depth of 1.8 ± 0.24 mm. A comparative analysis by crossed immunoelectrophoresis was carried out. Qualitatively evaluated orosomucoid and the complement factor C3 were degraded in all the gingival fluid samples, in contrast to those of plasma. A quantitative assay of 15 separate proteins in the two biological fluids showed reduced concentrations of alfa1‐antichymotrypsin, alfa2‐macroglobulin and haptoglobin in most gingival fluids. Orosomucoid, alfa1‐antitrypsin and C3 levels were decreased in all the gingival fluid samples. Reference ranges should be stated separately for the two biological fluids. The correlation coefficients between the plasma and the gingival fluid concentrations of each protein were calculated. The co‐variation was significant for 13 of the proteins studied. The ratio of the individual protein concentrations in the gingival fluid to that in the plasma was then calculated for each patient. A twoway analysis of variance of the variables patient groups and protein ratios showed that both effects were significant. Gingival fluid is an inflammatory exudate of serumal origin, but its protein profile is clearly modified by the local milieu.
Long term anti‐plaque gingivitis and calculus effects of benzethonium chloride in beagle dogs
Authors: Gaffar Abdul , Marcussen H. W. , Solls‐Gaffar M. C. , Rustogi K. N.
Published: July 2006

Beagle dogs were treated with 0.1 % aqueous solution of benzethonium chloride or with water for 27 weeks and for an additional three weeks to ascertain whether or not the plaque inhibiting effect of BTC was altered because of initial long‐term treatment. The results of this study show 0.1 % BTC significantly reduced plaque and gingivitis in beagles for 27 weeks, This plaque inhibitory effect of BTC was maintained in the subsequent three weeks, suggesting that its initial 27 weeks usage did not result in a change of “oral flora” that affected its efficacy.
The subgingival microbial flora during pregnancy
Authors: Kornman Kenneth S. , Loesche Walter J.
Published: July 2006

The subgingival bacterial flora from 2 gingival sites was cultured and characterized monthly in twenty periodontitis‐free women during pregnancy and again post‐partum. Monthly plaque samples were also cultured in eleven age and disease matched non‐pregnant women. Plaque was processed anaerobically on selective and nonselective media and the predominant colony types were characterized. A portion of each plaque sample was tested for bacterial uptake of C14‐estradiol and C14‐progesterone. Plasma levels of estrogens and progesterone were measured four times in each subject. The number of gingival bleeding sites, the Gingival Index and the Plaque Index were determined at each sampling period.

In the second trimester there was a significant increase in gingivitis, the ratio of anaerobic to aerobic bacteria, and the proportional levels of Bacteroides melaninogenicus ss. intermedius. In the third trimester both gingivitis and the levels of B. melaninogenicus ss. intermedius decreased. Plaque uptake of C14‐steroids increased significantly during pregnancy and paralleled the plaque levels of B. melaninogenicus ss. intermedius. In the second trimester, recovery of B. melaninogenicus ss. intermedius was strongly correlated with plasma levels of estrogens and progesterone. No changes were observed in clinical parameters or the subgingival flora of non‐pregnant subjects.

Pregnancy and specifically steroid hormones appear capable of influencing the normal bacterial flora and inducing alterations in the subgingival ecology.
The predominant cultivable dental plaque flora of beagle dogs with gingivitis
Authors: Syed S. A. , Svanberg M. , Svanberg G.
Published: July 2006

The predominant dental plaque flora of 15 female beagle dogs (1,3 and 6 year old) with naturally developed gingivitis was studied using a continuous anaerobic culturing technique. Supra‐ and subgingival plaque samples from the buccal aspect of the upper third premolar were cultured on various growth media and the organisms were partially characterized. The flora in all dogs was composed mostly of anaerobic Gram negative organisms. B. asaccharolyticus (B. melaninogenicus ss. asaccharolyticus) was found in both types of plaques in all animals and decomposed hydrogen peroxide suggesting catalase activity. F. nucleatum was found in higher proportions in the subgingival plaque as compared to B. asaccharolyticus and actinomycetes. Spirochetes were found in 10 of 15 supra‐ and in 1 of 15 subgingival specimens. S. mutans, S. mitior, S. salivarius, Veillonella, Selenomonas or vibrios could not be detected in any of the plaque samples. A combined data analysis showed, that the total viable CFU and the proportions of Gram positive organisms were significantly higher in the supra‐ than the subgingival plaque. Although the proportions of Gram negative bacteria were higher in subgingival plaque, the differences between the two types of plaques excluding F. nucleatum were not significant.
Local immunoglobulin synthesis in periodontal disease
Authors: Lally Edward T. , Baehni Pierre C. , McArthur William P.
Published: July 2006

The inflammatory lesions in advanced periodontal disease are characterized by a plasma cell infiltrate. In vitro synthesis of immunoglobulins (Ig) was detected by incorporation of 14C‐lysine and 14C‐isoleucine combined with immunoelectrophoresis and autoradiog‐raphy. IgG and IgA but not IgM synthesis was detected in chronically inflamed gingival tissues. No Ig synthesis was detected in histologically normal gingival tissue cultured under the same conditions or in predominantly fibrotic tissue. These results directly indicate that local synthesis does occur in diseased gingival tissues, suggesting that not all of the immunoglobulin in the gingival sulcus and gingival tissues are derived from the circulation.
The distribution of HLA‐A and ‐B antigens in patients and their families with periodontosis
Authors: Cullinan Mary P. , Sachs J. , Wolf E. , Seymour G. J.
Published: July 2006

To test the hypothesis of an association between periodontosis and the HLA‐complex, 30 unrelated patients and 8 families were tissue typed for HLA‐A and ‐B antigens. The patients were divided in two groups on an ethnic basis. Control groups consisted of unrelated individuals of the same ethnic origin. In the Negroid group I a statistically significant increase in the frequency of HLA‐BW35 was found. However, this significance was not apparent when compared to a control group matched for geographical location as well as ethnic origin. No statistically significant differences were observed in the Caucasoid group II. The segregation patterns of HLA and periodontosis in the families were not conclusive. Establishing whether unaffected younger siblings of the patients will develop periodontosis in the future complicated the analysis. More family studies are needed to assess whether the distribution of HLA haplotypes in affected siblings is indeed random as suggested by our data or not.
Salivary volatiles as indicators of periodontitis
Authors: Kostelc J. G. , Preti G. , Zelson P. R. , Stoller N. H. , Tonzetich J.
Published: July 2006

Volatile organic compounds in mouth air and saliva are useful in diagnosis of several systemic pathologies. Specific oral metabolites (ammonia, urea, volatile sulphur compounds) have been suggested as possible diagnostic and contributory factors to the etiology or pathogenesis of periodontitis. In this study, volatile organic compounds are characterized by gas chromatography/mass spectrometry from the headspace of incubated whole saliva from subjects with essentially normal oral health and subjects with moderate to severe periodontitis as rated by four oral health indices. Several compounds including aliphatic and aromatic alcohols, indole and dimethyl disulfide appear common to all subjects. Moreover, aromatic nitrogen containing compounds, i.e., pyridine and picolines, appear only in subjects with moderate to severe periodontitis. The occurrence of pyridine and picolines in the salivary volatiles of diseased subjects suggests that they are related to the disease process.