bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrastructural histochemistry of the dento‐epithelial junction
Authors: Kobayashi K. , Rose G. G.
Published: July 2006

The dento‐epithelial junctions (DEJ) of Rhesus monkeys were studied by electron microscopy for their histochemical responses to colloidal thorium and ruthenium red. Both of these cationic dyues are useful markers for the detection of acidic carbohydrates. With colloidal thorium, deposits occurred on the intercellular cell surfaces but not on the surfaces facing the tooth. The basal lamina, dental cuticle, desmosomes and hemidesmosomes reacted negatively. With ruthenium red, cell surfaces, desmosomal junctions, the peripheral densities and the spaces between the peripheral densities and the cell membranes of hemidesmosomes stained intensely. The lamina densa was also stained, but the lamina lucida and dental cuticle were negatively reacting. The negative reactions of the basal lamina and dental cuticle after colloidal thorium demonstrate the lack of acidic carbohydrates in both layers. With ruthenium red and periodic acid‐oxidation, the dental cuticle was denoted again to be negative for acidic carbohydrates. As for the reaction positive basal lamina with ruthenium red, we interpreted that the reaction was not due to acidic carbohydrates but potentially attributed to a protien moiety.
Ultrastructure of elestic and oxytalan fibres in dog gingivae
Authors: Soames J. V. , Davies R. M.
Published: July 2006

Fibres possessing the ultrastructural features of elastic tissue were located within the central area of the gingival connective tissue. They comprised an amorphous core surrounded by microfibrils 8–12 nm. in diameter. Beneath the junctional epithelium loose bundles of microfibrils of similar size, but lacking an amorphous component, corresponded to oxytalan fibres. Many of these inserted into the lamina densa of the basal lamina.
Evaluation of resultant tissue type following the intraoral transplantatin of various lyophilized soft tissues
Authors: Yukna Raymond A. , Sullivan William M.
Published: July 2006

Epithelial regeneration was studied in Rhesus monkeys following the placement of fresh autogenous and lyophilized allogeneic soft tissue grafts in alveolar mucosa recipient sites. Two months postoperatively, histologic evaluation of biopsied graft areas showed that the autogenous free gingival graft controls, lyophilized allogeneic skin, and lyophilized allogeneic gingiva generally demonstrated a keratinized surfrace and other attributes of gingival‐type tissue. Lyophilized allogeneic mucosa universally yielde a non‐ or para‐ keratinized surface and a mucosa‐like corium. These findings reinforce the principle of dermal dictation of epithelial covering, demonstrate that lyophilized tissues retain their dermal specificity, and support the use of lyophilized allogeneic skin and gingiva in mucogingival surgery.
Influence of age on the location of the maxillary mucogingival junction
Authors: Ainamo Anja
Published: July 2006

The aim of the study was to determine the influence of age on the location of the maxillary mucogíngíval junction. The material comprised orthopantomograms of 20 male and 20 female students aged 21–30 years and 20 male and 20 female adults aged 39–51 years. The mucogingival junction was revealed with Schiller's iodine solution and marked with short pieces of metal wire, attached to the teeth and gingivae with Squibb's Orahesive Dental Bandage in the midline of the facial surface of ech ototh. Orthopantomograms were taken to the marked dentitions with the X‐ray beam passing the horizontally positioned occlusal level at a –5° angle. From the radiographs the distance from the floor of the nasal cavity to the mucogingival junction was measured separately for each tooth to the nearest millimeter. The distance between the floor of the nasal cavity and the mucogingival junction was found to be the same in both age groups. Since thre is no reasons to believe that the floor of the nasal cavity would move downwards and certainly not upwards with advancing age, it was suggested that the mucogingival junction also remains at a constant location through adult life.
Oxytalan fibre response to tooth intrusion and extrusion in normal and lathyritic mice
Authors: Sims Milton R.
Published: July 2006

Springs were applied to the mandibles of normal mice to produce intrusion of one first molar and extrusion of the opposite first molar. Treatments were randomly allocated to the right and left sides of the jaw. The experiment was repeated in lathyritic mice. Hostologic sections demonstrated that major oxytalan fibres underwent marked changes in their angle of attachment to the cementum when comparing an intruded tooth with its extruded counterpart in either normal or lathyritic animals. A sample of 10 angular readings was tken from each tooth. A mixed model analysis of variance showed a significant difference at the 1% level in the angle attributed to the type of treatment applied. The data lend support to the hypothesis that oxytalan fibres are capable of independent function within the normal and also the pathologically affected periodontal ligament of mice.
Extraction of collagenase from human gingiva
Authors: Uitto Veli‐Juka , Turto Heikki , Saxén Leena
Published: July 2006

Collagenase that cleaves the native collagen molecule into two fragments was extracted from a homogenate of human gingiva obtained from subjects with periodontal disease. Collagenase activity was measured using radioactive type I collagen in solution as substrate and separating the reaction products by SDS acrylamide gel electrophoresis. Extraction of collagenase was performed with a neutral salt solution and the extract was fractionated using either ammonium sulfate or dioxane. Gel filtration was necessary for detection of collagenase activity in the extract. Considerable amounts of collagenase apparrently remained in the insoluble fraction of gingival homogenate bound to collagen fibers as indicated by digestion of gingival collagen during incubation at 36°C. Tissuebound collagenase was relased by heating the insoluble homogenate at 60° with calcium. Collagenase extracted either with saline or by the heat‐treatment was mainly in a latent form and was activated by brief exposure to trypsin.
Subcellular distribution and partial characterization of gingival mitochondrial and soluble malate dehydrogenases
Authors: Fine A. S. , Egnore R. W. , Scopp I. W. , Stahl S. S.
Published: July 2006

Partial purification and characterization by polyacrylamide gel electrophoresis of human and rodent malate dehyrogenase revealed the presence of two distinct isoenzymes, one associated with the mitochondrial fraction (M‐MDH) and one with the soluble fraction (S‐MDH). Electrophoretic mobilities of the isoenzymes obtained from human and rodent gingiva wre similar.

Malate dehyrogenase distribution patterns of the subcellular fractions suggest that the S‐MDH isoenzyme may be more active than the M‐MDH isoenzyme in rodent gingiva.

Malate dehydrogenase distribution patterns in mild to moderately inflamed human gingiva were similar to those seen in dilantin hyperplastic gingiva. S‐MDH and M‐MDH isoenzyme distribution patterns could not be fully evaluated because of the high activity of the M‐MDH isoenzyme seen in the soluble fraction. However, the subcellular distribution patterns and electrophoretic mobility in human gingiva showed trends similar to those seen in rodent gingiva. Malate dehydrogenase specific activities in total homogenates of human inflamed and dilantin hyperplastic gingiva were similar.
Acid mucopolysaccharides in porcine gingiva
Authors: Hiramatsu M. , Abe I. , Minami N.
Published: July 2006

Acid mucopolysaccharides (AMPS) were extracted from porcine gingiva. The concentration of the uronic acid extracted was 0.23% of the ry‐defatted issue. The AMPS were fractioned with a Dowex 1‐X2 column.

The individual AMPS components of the various fractions obtained were determine on the basis of the contents of the hexosamine, unsaturated disaccharides, and chondroitin sulfate isomers. It was suggested from the results that the AMPS of porcine gingiva consisted of large amounts of chondrotin sulfates A and B, moderate amounts of hyaluronic acid and heparan sulfate, and a small amount of chondroitin sulfate C.
Subcutaneous implants for assessements of dental materials with emphasis on periodontal dressings
Authors: Haugen Ellen , Mjör Ivarr A.
Published: July 2006

Polyethylene tubes filled with various dental materials were placed as subcutaneous implants in rats. A scoring system for no, slight, moderate and severe reaction was established on the basis of the tissue response to a variety of materials for the evaluation of long term implants (30 or 90 days). Short term implants (7 or 14 days) were evaluated by deciding whether or not an effect from the material could be found in addition to the operative trauma.

The scoring system was used to evaluate the reactions to three periodontal dressings. Tissue from the short term implantation periods exhibited marked reactions to most implants. Long term implantation revealed that a difference in the tissue response to the three dressings was present, For two of the materials the initial irritation was followed by an innocuous state, but from the third dressing a continuous irritation of the tissue was observed.
The influence of local anaesthesia and occlusal surface area on the forces developed during repetitive maximal clenching efforts
Authors: Van Steenberghe D. , de Vries J. H.
Published: July 2006

With local anaesthesia seven out of nine volunteers developed increased clenching forces during successive efforts with two antagonistic teeth. The magnitude of the increase could not be evaluated, as most subjects had to be prevented from clenching any harder, in order to avoid damage.

When a dynamometer was adapted bilaterally to several premolar and molar teeth, greater forces were developed than with the dynamometer adapted to two antagonists. This could be a result of decreased periodontal and/or pulpal receptor stimulation. In the former case, maximum clenching value was reached immediately, and the force remained almost constant during following clenching efforts.

Both experiments substantiate the hypothesis that periodontal and/or intradental receptors have a negative feed‐back on the activity of jaw closing muscles.
The effect of chlorhexidine and cetylpyridine on the binding of amaranth to saliva‐coated hydroxyapatite
Authors: Jensen Jørn Erik , Tustian Donald G.
Published: July 2006

The effects of chlorhexidine (CHX) and cetylpyridine (CPC) on the binding of an acidic food‐dye (amaranth) to hydroxyapatite treated with salivary proteins were studies. Apatite treated with proteins and CHX or CPC bound considerable amounts of amaranth, whereas protein‐coated apatite did not. The dye binding capacity of untreated apatite was dependent on the amount of CHX or CPC absorbed. CHX displayed much greater efficiency than CPC in promoting binding of dye. A mechanism of bisbiguanide‐ or quaternary ammonium‐mediated tooth stain formation is discussed.
Radiolabeled microsphere measurements of alveolar bone blood flow in dogs
Authors: Kaplan M. L. , Jeffcoat M. K. , Goldhaber P.
Published: July 2006

Radiolabeled microspheres were injected into the left cardiac ventricle in healthy adult dogs to quantify blood flow in maxillary and mandibular alveolar bone. Heart rate, arterial blood pressure and pulse contour were monitored throughout each experiment.

Blood flow in maxillary alveolar bone was more than 30 % greater (p < .001) than in mandibular alveolar bone. Alveolar bone blood flow (mean ± S.D.) measured as ml/min per gram was 0.12 ± .02 in the maxilla compared to 0.09 ± .02 in the mandible. The cardiovascular paramenters monitored were constant immediately prior to the injection of microspheres and remained unchanged during and following injection.

It is possible that radiolabeled microspheres can be used to quantify the circulatory changes in alveolar bone during the development of destructive periodontal disease in dogs.
A quantitative study of bone remodeling during experimental periodontal disease in the golden hamster
Authors: Baron Roland , Saffar Jean‐Louis
Published: July 2006

The aim of this study was to determine whether periodontal disease in the golden hamster, induced by a six‐month feeding of Keyes 2000 hyperglucidic diet, resulted in altered bone remodeling activity. The results show a significant increase in Howship's lacunae without changes in the extent of resorbing surface along the alveolar walls; this increase is associated with a significant decrease in the extent of bone formation surface. The same pattern is observed along the endosteum in the septa but is associated with a significant increase in the extent of actively resorbing surface. These results therefore indicate that there is a significant decrease in bone formation associated with the previously oberved increase in bone resorption during experimental periodontal disease.
Interaction of inflammatory cells and oral microorganisms
Authors: Baehni Pierre , Tsai Chi‐Cheng , Taichman Norton S. , Mcarthur William
Published: July 2006

The mechanisms of PMN lysosome release in response to dental plaque were investigated in virto. Human peripheral blood PMNs were exposed to pools of homologous supragingival and subgingival plaque. Under these condition, cells actively responded by releasing lysosomal markers (lysozyme, β‐glucuronidase, myeloperoxidase and lactorferrin) but bot lactate dehydrogenase, a non‐lysosomal enzyme, into the culture medium. Although phagocytosis of plaque. bacteria may be one mechanism to account for PMN lysosomal discharge, evidence is presented to support the concept that PMNs may be relevant in explaining the role of PMNs and lysosomes in the pathogenesis of periodntal disease.
A microbiological study of dental calculus
Authors: Sidaway D. A.
Published: July 2006

The flora of 16 supragingival and 11 subgingival calculus samples from 20 patients was studies using both selective media incubated aerobically and anaerobically. 767 representative isolates, from a total of 1,320 were charaterised and 653 assigned to genera or species.

Gram‐positive organisms present in >50% of all samples were Streptococcus sanguis (96%), Streptococcus mitior (93%), Actinomyces naeslundii (78%), Actinomyces israelii (72%), Rothia dentocariosa and Bacterionema matruchotii (70%) and Actinomyces viscosus (67%). the most prevalent Gram‐negative species were Neisseria pharyngis (89%), Selenomonas (80%), Fusobacterium nucleatum (78%), Bacteriodes melaninogenicus and Leptotrichia buccalis (70%), Camylobacter (60%), Veillonella alcalescens and an unidentified Gram‐negative rod (59%) and Eikenella corrodens (56%).

The calculus flora was more complex than histological studies had previously suggested, with up to 22 species found in a single sample. there was qualitative similarity with the flora of dental plaque formed at the margin of the gingivae, the chief difference being the absence of Streptococcus mutans and the increased prevalence of Str. sanguis serotype I/II.

A. naeslundii, A. viscosus and V. alcalescens were more prevalent in subgingival samples and N. pharyngis, B. melaninogenicus in supragingival. In view of the small number of samples examined these differences may not be highly significant.
Detachment od cells in vitro with culture fluids from stimulated human mononuclear cells
Authors: Neiders Mirdza E. , Horton John E.
Published: July 2006

Supernatants of cultured mononuclear cells (S‐MNL) were tested for their ability to separate cells from their substrates. Adherent L‐cells were exposed for up to 3 hr to culture fluids from MNL with and without PHA stimulation. A reproducible shearing force was then applied to the L‐cells which tests for loss of cohesiveness at the cell periphery. We found a significant increase of 3‐fold or greater in the number of detached L‐cells receiving stimulated S‐MNL when compared with culture fluids from unstimulated MNL. The detachment‐enhancing activity was present in culture fluids within 24 hours following stimulation. Examination of MNL culture fluids revealed no differences in the quantities of lysosomal enzymes to explain the increased cell detachment. We suggest the detachment of cells seen in vitro by products released from mononuclear cells may provide an explanation for the in vivo ability of these cells to infiltrate tissue.
Ultrastructural study of early dental plaque formation
Authors: Lie Tryggve
Published: July 2006

Initial Colonization and early plaque formation were studied using hydroxyapatite splint segments attached to buccal surfaces of maxillary molar and premolar teeth in six young adults given a low‐sucrose diet. Segments were removed at intervals of 2, 4, 6, 12, 24 and 48 hr. Bacteria were first regularly seen in 4 or 6 hr specimens where they occurred as individual cells or as small groups of cells. No structures resembling preformed aggregates or hemispherical bacterial “globules” could be demonstrated. The bacteria most frequently attached to the pellicle surface diectly by their cell wall and gram‐positive cocci were most abundant. Another mode of bacterial attachment to pellicle was by means of fine bifbrils or coarser thread‐like structures. Occasionally organisms were seen attaching to apatite surfaces without interjacent pellicle material and sometimes they appeared to be completely embedded in the pellicle. Bacteria colonizing on epithelial cells regularly displayed a “fuzzy coat”. Extensions of organic material from the pellicle surface sometimes made it difficult to distinguish between pellicle and plaque matrix. No clear indication of bacteria metabolizing the pellicle was seen. Trilaminar vesicles probably originating from the surface of degenerating cells were especially abundant in areas with Gramnegative bacteria. In areas with Gram‐positive cells the amount of plaque matrix was greater and a number of cells displayed surface threads. The outer surface of the plaque ordinarily did not show a layer of extracellular organic material although a granular laer could be seen in local areas. These findings lend support to a concept of plaque formation as a sequential build‐up resulting from selective attachment and growth of individual organisms rather than resulting from attachment of aggregates of bacteria or a passive entrapment of organisms in a matrix.
The effects of local immunization with periodontopathic microorganisms on periodontal bone loss in gnotobiotic rats
Authors: Crawford John M. , Taubman Martin A. , Smith Daniel J.
Published: July 2006

Experiments were performed to study the effect of stimulation of salivary antibody on the progress of periodontal bone loss in monoinfected rats. Animals were immunized with formalin‐killed S. mutans, A. naeslundii or A. viscosus in the region of each major salivary gland and then inoculated orally with live homologous organism. Salivary and serum antibody activities were measured by microagglutination. The contribution of IgA to the activity in saliva was further assessed by antiglobulin augmentation with class specific antiglobulin eagents directed to rat immunoglobulins. In certain experiments the presence of delayed hypersensitivity was investigated by skin testing. Periodontal bone loss was assessed by measurement of both horizontal and vertical bone loss. Estimation of the number of bacteria colonizing the teeth at the termination of each experiment was also made. Inexperiments with S. mutans or A. naeslundii, when relatively high levels of salivary antibody directed to the homologous organism were elicited by local injection, definite trends toward reductions in periodontal bone loss occurred. Serum antibody was also present in immunized animals. Fewer bacteria were generally recovered from immunized rats than from sham‐immunized rats. Delayed hypersensitivity to A. viscosus was accompanied by an increase in vertical bone loss. It is suggested that inflammatory lesions contributing to periodontal disease might be modified by manipulation of the host's immune system.
Citation records of papers published in the journal of periodontology and the Journal of Periodontal Research
Authors: Brunette D.M. , Simon M.J. , Reimers M.A.
Published: July 2006

The citation records of the papers published in the Journal of Periodontology vols. 31–45 and Journal of Periodontal Reserch vols. 1–9 have been examined and lists of most cited papers ranked by total number of citation and citations per year compiled. Several diverse approaches to periodontal research are represented in these lists including microbiology, histology, immunilogy. and surgery.

The patterns of periodontal literature usage with time resembles that found for biomedical lliterature and other bibliographic indices such as Price's Index and the number ro references per paper place periodontal research in or close to the range of values found for “normal” sciences.

The distribution of citations among individual papers resembles that found in other sciences in that the majority of papers have very little impact. In the first five years following publication, 18% of papers published in J. Periodontol. were not cited while less than 10% were cited ten times or more. The record for papers published in J. Periodontal Res. is slightly better, 9.5% were not cited and 12.6% were cited ten times of more in the five years following publication. In this study. there were no instances of papers that failed to be cited in the first five years achieving ten or more citations in any subsequent five year period. One class of research publication, case reports, was associated with a very low citation frequency. It appears that the influence fo case reports on subsequent research is small.
Interaction of inflammatory cells and oral microorganisms
Authors: Tsai C.‐C. , Hammond B.F. , Baehni P. , McArthur W.P. , Taichman N.S.
Published: July 2006

The purpose of this study was to asceertain if representative Gram‐negative microorganisms isolated form human dental plaque could stimulate the relesase of lysosomal constituents from human peripheral blood or rabbit peritoneal polymorphonuclear leukocytes(PMNs). All microorganisms tested in this study can act as periodontal pathogens in experimental animals. With the exception of Y4, a Bacteroides‐like Gram‐negative mkicroorganism, all bacteria triggered PMN lysosome release in absence of serum components. Electron microscopic observations indicated that degranulation and release of PMN lysosomes were associated with phagocytosis of Gram‐negative bacteria. Serum had modulating effects on PMN release, generally enhancintg release reactions to all bacteria including Y4. These data suggest that PMN interactions with Gram‐negative bacteria may be one important mechanism in the pathogenesis of gingival and periodontal inflammation.
Experimental cellular immune reactions in the gingiva of beagle dogs
Authors: Rylander H. , Attstroöm R. , Lindhe J. , Nobreus N.
Published: July 2006

Four Beagle dogs were sensitized to 1‐dinitro‐2.4 chlorobenzene (DNCB) during a preexperimental period of three months. The animals were fed a hard diet and subjected to plaque removal three times weekly throughout the study. During the experimental period of 75 days DNCB was applied to the gingiva three times weekly on one side of the jaws and the vehicle (Orabase) was applied on the other. Gingival biopsies were taken on day 75 of the experiment. Semithin sections were subjected to light microscopic analysis using morphometric point counting procedures. The mor0phometic data showed that the gingiva on the experimental (DNCB) side contained leukocyte inflitrates dominated by mononuclear inflammatory cells, in the marginal oral epithelium, junctional epithelium as well as in the connective tissue immediately below these epithelia. The oral epithelium was the site of severe alterations such as intercellular edema and lack of a stratum corneum. In the diseased portion of the connective tissue the establishment of a lymphocyte‐macrophage dominated infiltrate was secured simultaneously with a drastic reduction of the collagen content.

The results of the study indicate that the reaction elicited in the tissues was related to delayed hypersensitivity and that the establishment of an experimental cellular immune reaction caused damage to the gingival structures.
The effect of autogenous cancellous bone grafts on gealing of experimental furcation defects in dogs
Authors: Nilvféus Rolf , Johansson Owe , Egelberg Jan
Published: July 2006

Chronic, through‐and‐through, furcation defects were created in mandibular premolars of six beagle dogs. These defects were surgically treated without autogenous, cancellous, bone grafts. Healing sockets in the maxilla serged as donor sites. Block specimens were removed after eight weeks. All teeth from all dogs showed some reattachment after treartment as evidenced by newly formed cementum. None of the specimens showed complete regeneration, i.e.a periodontal membrane with new cementum all aroune the fornix of the furcation. Histometric measurements showed that the use of osseous grafts did not improve the results in the present experimental model.
The effect of topical citric acid application on the healing of experimental furcation defects in dogs
Authors: Crigger Max , Bogle Gary , Nilvéus Rolf , Egelberg Jan , Selvig Knut A.
Published: July 2006

Periodontal furcation pockets were created in the mandibular premolar teeth in eight Labarador retriever dogs. Six months later, a surgical debridement procedure aimed at closing the furcation defects was carried out. On either the right or left side in each dog, a cotton pledget saturated with citric acid (pH 1) was inserted into the furcation for 3 minutes. One tooth in each animal was left untreated. Block biopsies were removed after 6 weeks and processed for histological evaluation. All of the non‐acid treated and the unoperated teeth revealed a patent, epithelialized furcation defect, whereas 21 of 23 acid‐treated furcations showed closure of the furcation in mesio‐distal sections. The instrumented root surface was covered with a thin layer of cementum to which periodontal fibers were attached. The bone level was significantly higher in the acid‐conditioning of the root surface may increase the rate of success of new‐attachment procedures and does not seem to have an adverse dffect o soft tissue healing or bone regeneration.
The natural history of periodontal disease in man
Authors: Löe Harald , ÅNerud ÅGe , Boysen Hans , Smith Martyn
Published: July 2006

The meaterial presented in this report was derived from an longitudinal studt of the development and progress of periodontal disease and resultant tooth loss. The first population group was established in Oslo, Norway in 1969 and consisted of 565 male, non_dental students and academicians between 17 and 30+years. a nad second group was established in Sri Lanka in 1970 and consisted of 480 male tea loborers between the first and fourth examination was in Oslo 6 years and 3 months, in Sri Landka 7 years and 6 months. Each participant was scored for various disease parameters and the number of permanent teeth (third molars excluded) was recorded at each examination. The results show that in these randomly sampled groups no one was edentulous. The 17 year old Norwegian had 27.4 teeth present out of 28 possible and no major loss of teeth occurred during the twenties and thirties. As the participants approched 40 years of age, the mean number of teeth present was 27.1 and the mean mortality rate was 0.01 teeth per year. The Sri Lankan 15 year old had 27 teeth present and the 40 year old had 25.6 teeth. The mean mortality rate ranged between 0.1 and 0.3 teeth per year. Teeth with deep periodontal lesions started to exfoliated in Sri Lankans as they approached 40 years of age.
Impaired neutrophil chemotaxis in patients with juvenile and rapidly progessing periodontitis
Authors: Lavine W. S. , Maderazo E. G. , Stolman J. , Ward P. A. , Cogen R. B. , Greenblatt I. , Robertson P. B.
Published: July 2006

Polymorphonuclear leukocyte chemotactic studies were performed in young patients with juvenile periodontitis/periodontosis and adult patients with aggressive periodontitis. In the juvenile periodontitis/periodontosis group, 86% showed modest leukotactic defects, the majority of which were due to intrinsic abnormality of cells. In the older patients with rapidly progressing periodontitis 48% had detectable leukotactic defects; the majority of which were serum associated. The results indicate that some forms of periodontitis are associated with impaired polymorphonuclear leukocyte chemotaxis and suggest that a failure of a major host protective mechanism to dental plaque may increase susceptibility to periodontal disease.
Ultrastructural studies of infalmmation induced in rats by injection of antigen‐antibody precipitates
Authors: Garant P. R.
Published: July 2006

Single intramucosal injectins of ferritin‐antiferritin into the palate adjacent to the 1st molar produced a dense neutrophil infiltration within perivscular tissue adjacent to the palatal bone. Neutrophil degranulatin related to the phagocytosisi of antigen‐antibody (Ag‐Ab) precipitates occurred during the 1st 24 hours post injection. Rapidly developing bone damage was characterized by periosteal disruption, osteoblast and osteocyte necrosis and occasional swquestration of necrotic bone. Cytoplasmic changes such as dilated endowere observed inosteoblasts within 2 hrs of Ag‐Ab injection. Wound healing with regeneraionof periosteal tissue at the margins of the lesion was observed to begin at 4 days post injection. New bone was formed directly over the older necrotic bone without any intervening bone resorption. Extracellular matrix vesicles were observed adjacent ot newly differentiated bone cells.
The effect of systemic antimicrobial therapy on plaque and gingivitis in dogs
Authors: Listgarten M. A. , Lindhe J. , Parodi R.
Published: July 2006

Six dogs with varying degrees of gingivitis wer divided into 3 groups of 2 dogs each. One pair of dogs received tetracycline HCI 250 mg, 2 times/day, for 4 weeks. The controls reveived no medication during the experimental period of 4 weeks. The results showed a decrease in the proportions of coccoid cells and straight rods in the periodontal flora with increasing gingival inflammation, while the proportions of spirochetes and motile bacteria were markedly reduced. Metronidazole appeared to be somewhat more effective in eliminating spirochetes than tetracycline. Treatment with the antimicropbial drugs tended to derease the size of th infiltrated connective tissue as well as the proportion of junctional epithelium occupied by inflammatory cells, but did not succeed in eliminating the inflammatory reaction entirely. At the initial examination around 60% of the leukocyte volume in junctional epthelium consisted of neutrophilic granulocytes. At the final examination less than 30 % of the leukocyte volume consisted of neutrophis. It was not clear from the results if the improvement in the clinical and histological parameters was due to the specific suppression of ertain organisms or to an overall. non‐specific reduction in volume of the periodontal flora.
An in vitro study of factors affecting the development of staining associated with the use of chlorhexidine
Authors: Prayitno S. , Addy M.
Published: July 2006

A previously developed spectrophotometric measurement technique was employed to study factors which may affect the development of tea staining on chlorhexidine treated perspex specimenas. Thus the effects of the frequency of exposure of the specimens to, and the concentration of, the chlorhexidine gluconate solution on the development of staining, was assessed. Furthermore, the staining of test and control specimens previously esposed to pooled humna saliva was measured. All three parameters investgated had a significant effect upon tea staining of chlorhexidine treated specimens. Thus, there was a direct relationship between staining and the frequency of exposure to chlorhexidine. With increasing chlorhexidine concentration staining increased to an optimum at 0.1%. Pretreatment of specimens with saliva increased significantly the staining of both test and control specimens. however, the staining of test specimens remained significantly greater than the control specimens.
An in vitro study of the role of dietary factors in the aetiolgy of tooth staining associated with the use of chlorhexidine
Authors: Addy M. , Prayitno S. , Taylor L. , Cadogan S.
Published: July 2006

A spectrophotometric measurment technique was employed to investigate the role of dietary factors in the aetiology of chlorhexidine staining. Standard solutings were prepared form a range of dietary components. Test perspex specimens were maintained n the standard solutions throughout a five day period being removed from the solutions three times a day and soaked in a 0.2% chlorhexidine gluconate solution. Control specimens were similarily treated but not exposed to chlorhexidine gluconate. Daily optical density recording demonstrated some staining of specimens by all dietary components. However of most there was no significant difference between test and control specimens and in visual terms such staining was very minimal. Navertheless, tea, red wine and port produced rapid and heavy staining on test specimens which was highly significantly increased when compared to control specimens. Coffee similarly produced more staining of test specimens compared to contrl specimens; however, the intensity of staining was coniderably less. Employing the sake experimental method, both cigarette smoke and cigarette smoke in colution Produced significantly more staining of control specimens compared to test specimens.
Sialic acid concentration in the attached gingival tissue of rates realted to age and sex
Authors: Nicolau Jose , Paiva Yvonne A.S.
Published: July 2006

Determination of N‐acetylneuraminic acid concentration in the attached gingival tissue of rats related to the age and sex of the animals was carried out. The concentration of the sialic acid decreased with increasing age. Differences between male and female animals were noted.
An ELISA for measuring serum antibodies to Actinobacillus actinomycetemcomitans
Authors: Bersole Jeffrey L. , Frey Deirdre E. , Taubman Martin A. , Smith Daniel J.
Published: July 2006

An adaptation of the indirect enzyme‐linked immunosorbent assay (ELISA) is described for the determination of isotype specific antibodies directed to intact Actinobacillus actinomycetemcomitans and bacterial sonicates. Sera from nine individuals, with or without diagnosed periodontal disease, have been examined for IgG antibodies to the microorganism. The conditions for the assay have been studied and the ELISA has been compared to bacterial agglutination, indirect immunofluorescence or passive hemagglutination. A positive correlation is noted among the analyses in separating the sera into high, moderate and low antibody activities. However, based upon the highest dilution of the sera that gave positive reactions in the assays, the modified ELISA is 5–50 fold more sensitive than either the microagglutination, indirect immunofluorescence or passive hemagglutination techniques as performed. The ELISA is a sensitive assay that uses small quantities of biological materials to determine isotype specific antibody levels. This assay can provide a means for rapid screening of large numbers of biological samples for antibodies to intact microorganisms.
Interactions between bacterial endotoxin and other stimulators of bone resorption in organ culture
Authors: Raisz Lawrence G. , Nukj Klaus , Alander Cynthia B. , Craig Ronald G.
Published: July 2006

Four agents which have been implicated in the pathogenesis of alveolar bone loss. In periodontaI disease, endotoxin, prostagandin E2 (PGE2), parathyroid hormone (PTH) and osteoclast activating factor (OAF), were studied for their effects on bone resorption as measured by the release of previously incorporated 45Ca from long bone shafts of 19 day fetal rats. Endotoxin at concentrations of 4 to 25 ng/ml caused little increase in 45Ca release but was able to enhance the response to submaximal concentrations of PGE2, PTH, and OAF. The response appeared synergistic, that is, it was greater than the sum of the individual responses when the agents were added singly. PTH and PGE2 do not show such apparent synergism when added together. The effects of endotoxin were not inhibited by three structurally unrelated inhibitors of prostaglandin synthesis, indomethacin, flufenamic acid and RO 20–5720, and synergistic responses were similar when PGE2 and endotoxin were added in the presence of indomethacin. We conclude that interactions between endotoxin and other bone resorbers can produce unexpectedly large resorptive responses and suggest that these interactions may be important in the pathogenesis of bone loss in periodontaJ disease and other forms of pathologic osteolysis.
Pilot clinical studies on the effect of topical citric acid application on healing after replaced periodontal flap surgery
Authors: Cole Rick , Nilveus Rolf , Ainamo Jukka , Bogle Gary , Crigger Max , Egelbekg Jan
Published: July 2006

The effect of citric acid conditioning of the root surfaces during periodontal surgery was studied in 12 patients with residual pockets ≥ 5 mm two months following oral hygiene instruction and initial root planing. Full thickness, replaced flap procedure (“modified Widman”) was performed with or without topical citric acid application using a split mouth approach. Six months post‐operatively, improvement of the periodontal conditions was observed as evidenced from reduction of probing pocket depth, gain of probing attachment level and gingival recession. A mean probing attachment level gain for pooled acid treated surfaces of 2.1 mm was obtained as compared to 1.5 mm for the non‐acid treated control surfaces.

Our previous dog and human studies have demonstrated new connective attachment after acid conditioning of root surfaces as contrasted to readaplation of a junctional epithelium in the non‐acid treated controls. However, the results of the present study indicate that from a clinical standpoint, the use of citric acid application might only provide a small improvement in probing attachment levels.
The progress of the periodontal syndrome in the rice rat
Authors: Gotcher J. E. , Jee W. S. S.
Published: July 2006

The effects of a diphosphonate, dichloromethylene diphosphonate (C12MDP) were studied using the rice rat as a model of periodontal bone loss. C12MDP was given in daily subcutaneous injections at dosages of 0 (control), 0.1, 1.0, or 10.0 mg/kg/day; these treatments were continued for periods of 6, 12, or 18 weeks. The amount of alveolar bone was increased over age matched controls at the 1.0 and 10.0 mg/kg/day doses at 6 weeks; at 12 and 18 weeks, all doses including 0.1 mg/kg/day showed increases in bone over controls. Due to increased connective tissue fibrosis, the CI2MDP treated animals had fewer vascular spaces. Also, the amount of destroyed tissue in the interdental test site was increased in animals given 10.0 mg/kg/day of C12MDP. The number of fibroblasts per mm of bone surface decreased slightly at 6 weeks, but was otherwise not different from controls in treated animals at 12 and 18 weeks. Numbers of osteoblasts decreased greatly at all doses at both 12 and 18 weeks time. There were no significant differences between treated and control animals in the number of osteoclast nuclei per mm bone surface. Also, the numbers of inflammatory cells residing at the bone surface increased at all time periods in the 10.0 mg/kg/day dose group. Finally, the proliferative activity of PDL fibroblasts decreased dramatically at all time periods in the 10.0 mg/kg/day dose group. The response of the proximal tibia to C12MDP was compared to the alveolar bone response in these animals by measuring amounts of bone in respective areas. While the dose response curves are similar, the tibiae showed greater increases in bone mass.
The relationship between degree of development of tooth isografts and the subsequent formation of bone and periodontal ligament
Authors: Barrett Anthony P. , Reade Peter C.
Published: July 2006

Incompletely formed teeth isografted to the renal subcapsular site in mice demonstrated alveolar bone and periodontal ligament formation when examined by histological methods 60 days after transplantation. On the other hand bone and periodontal ligament formation was not observed in relation to isografts of fully formed teeth at the same site and time after transplantation. It is possible that surviving remnants of Hertwig's root sheath and the dental follicle play a part in the development of the periodontium of isografts partially developed at the time of transplantation although the mechanisms and source of cells involved are not yet clear.
The lag phase factor in bone healing
Authors: Amler Melvin H.
Published: July 2006

An analysis of the age and lag phase factor in human bone healing has been conducted utilizing histological and histochemical techniques, based on an effective number of sixtyfive biopses from subjects screened to eliminate medical disorders or nutritional deficiencies that might have interferred with normal healing. The time required for most active regeneration appeared to depend on the subject's age: a mean of approximately 10 days for subjects in the second decade of life and a mean of approximately 20 days for individuals in the sixth decade or older. It is postulated on the basis of this study and from interpolation from previous, preliminary studies in the rat, that it would be more advantageous to transplant marrow at its most actively regenerating stage rather than at its maturity and that the most actively regenerating time period depends on the age of the individual.
Specificity of gingival plasma cells for bacterial somatic antigens
Authors: Schonfeld Steven E. , Kagan Jonathan M.
Published: July 2006

Human gingival tissue biopsies were classified as “initial or early” or “established or advanced” periodontal lesions on the basis of the histopathological criteria of Page and Schroeder (1976). The percentage of plasma cells in each specimen that could recognize somatic antigens associated with one of four bacterial strains was then determined by incubating frozen sections of the gingiva with rhodamine‐labeled bacterial cells. The sections were also briefly incubated with a fluorescein‐labeled antibody to human immunoglobulins to facilitate plasma cell detection. Of the bacterial strains tested (Bacteriodes gingivslis, Actinomyces viscosus strains ATCC 27044 and T14–V, and Actinobacillus actinomycetemcomitans). only B. gingivalis was found to bind to a significantly higher percentage of plasma cells in the more advanced lesions as compared with the earlier lesions (16.3 % versus 3.7 %). These results suggest an important role for somatic antigens associated with B. gingivalis in the immunopathogenesis of human periodontitis.
Bacteroides gingivalis antigens and bone resorbing activity in root surface fractions of periodontally involved teeth
Authors: Patters M. R. , Landesberg R. L. , Johansson L.‐A. , Trummel and C. L. , Robertson P. B.
Published: July 2006

Bone resorbing activity and the presence of antigens of Bacteroides gingivalis were assessed in plaque, calculus, cementum, and dentin obtained from roots of teeth previously exposed to periodontitis. Each fraction was obtained by scaling the root surface. The fractions were extracted by stirring and sonication, and the soluble extracts centrifuged, sterilized, dialyzed, and adjusted to equivalent protein concentrations. Cementum and dentin extracts from impacted teeth were prepared similarly and served as controls. Stimulation of bone resorption by each extract was assessed in organ cultures of fetal rat bones by measurement of release of previously‐incorporated 45Ca from the bone into the medium. In some groups of teeth, calculus and cementum were treated with citric acid prior to scaling. Citric acid washes were recovered and dialyzed. An enzyme‐linked immunosorbent assay (ELISA) was used to assess the extracts for the presence of antigens reactive with an anti‐serum to B. gingivalis.

Significant stimulation of bone resorption was found in all calculus and periodontally‐involved cementum preparations. ELISA showed significant levels of B, gingivalis antigens in plaque, calculus, and cementum of periodontally‐involved teeth, but not in involved dentin nor in cementum or dentin of impacted teeth. Treatment with citric acid removed essentially all B. gingivalis antigens from cementum but not calculus.

The results suggest that substances which stimulate bone resorption and substances which react with B. gingivalis antiserum are present in surface plaque, calculus, and cementum of periodontally‐involved teeth. These substances are not present in cementum and dentin of impacted teeth nor in dentin of periodontally‐involved teeth. Treatment by both scaling and citric acid demineralization will remove most of these substances from cementum of teeth previously exposed to periodontitis.
Detection of elevated serum antibodies to Treponema denticola in humans with advanced periodontitis by an enzyme‐linked immuno‐sorbent assay
Authors: Jacob Elliot , Meiller Timothy F. , Nauman Robert K.
Published: July 2006

The enzyme‐linked immunosorbent assay (EL1SA) was used for the detection of circulating antibodies in human sera to antigens of three serotypes ofTreponema denticola. The antigens used in the assay were obtained by a sodium deoxycholate extraction procedure. Sera obtained from totally edentulous patients, patients with advanced periodontitis, as well as dental students who were in good to excellent periodontai health were tested for antibodies to these antigens by ELISA. Significantly elevated antibody levels were detected in 10/11 patients with advanced periodontitis towards the antigens of all 3 serotypes. In contrast, ll/ 13 edentulous patients were negative for antibodies to serotypes W and TT and 9/13 were negative against serotype 11. In the mild gingival inflammation group, 11/14 individuals were negative against serotypes W and 11, and all were found to be negative against serotype TT. Adsorption studies carried out with 4 highly reactive sera indicated that the IgG antibodies detected by ELISA were specific for these antigens ofT. denticola.The results of these studies are at variance with those of previous investigators who reported the total absence of detectable antibodies to T. denticola in sera from patients with advanced periodontai disease.
Alveolar bone destruction in the immunosuppressed rat
Authors: Sallay K. , Sanavi F. , Ring I. , Pham P. , Behling U. H. , Nowotny A.
Published: July 2006

The placement of a ligature around the second maxillary molar of the conventional rat caused osteoclastic bone resorption and simultaneously, alveolar bone formation. The number of peripheral mononuclear cells in the blood and lymphoblastic transformation of spleen cells in response to concanavalin A increased. Cyclophosphamide (CY), an immunosuppressive agent, given shortly after placing the ligature suppressed the lymphoid reactions, spleen size, and bone formation and enhanced bone destruction. CY given in higher doses also suppressed the number of PMN cells. Septicemia developed in several of these animals. Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli were isolated from the blood and/or ligature. Antibiotics prevented bone destruction. Without placing a ligature, the high dose of CY did not result in bone loss.

These findings suggest that 1) bone destruction of the ligature‐treated rat is of bacterial origin, 2) CY suppresses proliferation of osteoblasts but does not seem to interfere with the activity of osteoclasts, and 3) suppression of the host defenses greatly facilitates bone destruction.