bluuebunny/crossref_metadata_2025 huggingface dataset:
Periodontal Pathogens Stimulate CC‐Chemokine Production by Mononuclear and Bone‐Derived Cells
Authors: Jiang Yanling , Graves Dana T.
Published: February 2005

Background: Chemokines are chemotactic cytokines that stimulate recruitment of leukocytes. Monocyte chemoattractant protein‐1, macrophage inflammatory protein‐1α, and RANTES (regulated on activation, normal T cell expressed, and secreted) are 3 well‐characterized CC‐chemokines that regulate mononuclear cell recruitment. The recruitment of inflammatory cells is of particular importance in the oral cavity because of the likelihood that cells will be challenged with bacteria either during acute infection or following surgical procedures. Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans are putative periodontal pathogens that may be harbored in subgingival and supragingival plaque. The capacity of the host to respond to these bacteria by the elaboration of chemoattractants may represent an important defense mechanism.

Methods: In the present study, we examined CCchemokine production by human mononuclear cells and bone‐derived cells in response to P. gingivalis, A. actinomycetemcomitans and lipopolysaccharides (LPS) stimulation in vitro. The chemokines produced were measured by ELISA.

Results: The results demonstrate that P. gingivalis and A. actinomycetemcomitans induce high levels of MIP‐1α in mononuclear cells. P. gingivalis and A. actinomycetemcomitans stimulated high levels of MCP‐1 in bone‐derived cells and induced moderate levels of RANTES production in both mononuclear and osteoblastic cells. In mononuclear cells, LPS induced high levels of MIP‐1α and RANTES and moderate levels of MCP‐1; in osteoblasts LPS only induced MCP‐1.

Conclusions: The capacity of bacteria to induce a given chemokine depends upon the cell type stimulated. That different cell types would exhibit differences in the CC‐chemokines produced under the same stimulus provides a mechanism to explain tissue‐specific recruitment of leukocytes. J Periodontol 1999;70:1472‐1478.
The Accuracy of Radiographic Methods in Assessing the Outcome of Periodontal Regenerative Therapy
Authors: Toback Gregory A. , Brunsvold Michael A. , Nummikoski Pirkka V. , Masters Lisa B. , Mellonig James T. , Cochran David L.
Published: February 2005

Background: The study of regenerative therapy in the periodontal intrabony defect has relied upon surgical re‐entry as the gold standard of outcome assessment. The search for a non‐invasive method has led to the application of various radiographic techniques in evaluating post‐treatment bone fill.

Methods: The purpose of this study was to determine the ability of 2 forms of radiographic analyses (linear measurement and computer assisted densitometric image analysis, CADIA) to assess postsurgical bone fill as measured at a re‐entry procedure. A method that incorporates linear measurements and CADIA (linear‐CADIA) was developed and tested as well. Forty‐five intrabony defects in 15 patients were treated with open flap debridement, demineralized freeze‐dried bone allograft (DFDBA), or a combination of DFDBA and tetracycline. Standardized radiographs were obtained at baseline and at 1‐year postsurgery.

Results: A 12‐month surgical re‐entry provided clinical measurements for post‐treatment bone fill. All radiographs were digitally scanned and analyzed on a computer. Fifty‐three percent of the defects were excluded from the study due to poor standardization or poor defect quality. Forty percent of all pairs of radiographs were judged to have poor standardization. In the first analysis, standardized images were subtracted and quantitatively analyzed utilizing CADIA. It was found that CADIA had the highest correlation with clinical bone fill when a region of interest (ROI) was examined in the middle portion of the defect. This quantitative evaluation provided very little clinically relevant information regarding actual bone fill. For the second analysis, pre‐ and post‐treatment linear radiographic measurements were obtained. In only 43% of the sites, did linear radiographic measurements determine post‐treatment bone fill within 1.0 mm of the clinical measurements. Overall, linear measurements underestimated bone fill by 0.96 mm (±1.2). These differences were statistically significant (paired Student t‐test, P = 0.0023). A method, which incorporates the use of both CADIA and linear radiographic measurements (linear‐CADIA), was tested. The linear‐CADIA method underestimated bone fill by 0.26 mm (±1.4), but these differences were not statistically significant (paired Student t‐test, P = 0.41).

Conclusion: Linear radiographic measurements significantly underestimate post‐treatment bone fill when compared to re‐entry data. The linear‐CADIA method provided the highest level of accuracy of the 3 methods tested. This study also emphasizes the importance of developing a consistent method of radiographic standardization. J Periodontol 1999;70:1479‐1489.
Periodontal Disease in Patients With cleft Palate and Patients With Unilateral and Bilateral Clefts of Lip, Palate, and Alveolus
Authors: Gaggl Alexander , Schultes Günter , Kärcher Hans , Mossböck Rudolf
Published: February 2005

Background: Long‐term health of the stomatognathic system, as well as esthetics, is the therapeutic goal in patients with facial clefts. The aim of this study was to analyze the periodontal situation of patients with cleft palate (CP) and cleft alveolus (CLPA) to elicit the differing degrees and localization of periodontal disease.

Methods: In 30 patients with unilateral cleft lip, palate, and alveolus (UCLPA), 30 patients with cleft palate (CP), and 20 patients with bilateral cleft lip, palate, and alveolus (BCLPA), the gingival situation was identified and classified according to the sulcus bleeding index (SBI). Periodontal attachment loss and pathological loosening of teeth were noted for identification of periodontal lesions. The state of oral hygiene was recorded by the approximal plaque index (API).

Results: In general, poor oral hygiene was found in all patients. The SBI showed a high incidence of gingivitis in patients with cleft lip, palate, and alveolus. Patients with cleft palate had a minor extent of sulcus bleeding, Periodontal disease was found to a similar extent to that in the general population in patients with cleft palate, whereas patients with cleft lip, palate, and alveolus had a predisposition to deep periodontal destruction of teeth adjacent to the cleft. The registration of pathological loosening of, a result of attachment loss, corresponded to the degree of periodontal disease shown by the attachment loss.

Conclusions: A critical periodontal situation was found in patients with unilateral and bilateral cleft lip, palate, and alveolus. ultimately leading to tooth loss in the front tooth region. In contrast, patients with cleft palate exhibited periodontal situations similar to that found in the general population with additional damage, which may be attributed to orthodontic treatment. J Periodontal 1999;70:771‐178.
Polyamines Found in the Inflamed Periodontium Inhibit Priming and Apoptosis in Human Polymorphonuclear Leukocytes
Authors: Ratasirayakorn Waraporn , Leone Peter , Leblebicioglu Binnaz , Walters John D.
Published: February 2005

Background: Polymorphonuclear leukocytes (PMNs) are exposed to high concentrations of polyamines in the inflamed periodontium and possess a transport system for taking up these compounds. Previous studies suggest that polyamines are involved in priming of the PMN respiratory burst by tumor necrosis factor‐α (TNF‐α) and can stabilize DNA against degradation. The purpose of this study was to determine whether exogenous polyamines can modulate priming by TNF‐α or delay nuclear changes associated with PMN apoptosis (programmed cell death). Methods: Isolated human PMNs were incubated with putrescine or spermidine in vitro. Superoxide generation was measured with a cytochrome C reduction assay, and apoptotic changes were assessed by fluorescence microscopy (after cell staining with acridine orange and ethidium bromide).

Results: Incubation with 1 mM putrescine for 1 hour inhibited superoxide production by TNF‐primed PMNs by 20%, but enhanced the production of superoxide by unprimed cells by 38%. Both effects were dose dependent and statistically significant (P <0.03, repeated measures ANOVA and Dunnett's test). Spermidine had no significant effects on PMN oxidative function. With regard to apoptosis, 1 mM putrescine or spermidine produced a statistically significant reduction in the proportion of apoptotic PMNs within 6 to 9 hours (P <0.05). In cells incubated for 7 hours with 300 µM putrescine or spermidine, the proportion of apoptotic cells was approximately 30% lower than in untreated controls (P <0.05, Dunnett's test). The delay of apoptosis by spermidine was less profound than that produced by TNF‐α and was not additive to the effects of this cytokine.

Conclusions: Polyamines could potentially impair the priming of PMN oxidative function by TNF‐α at sites where this cytokine is present. In the absence of TNF‐α, polyamines could enhance PMN superoxide release and enhance the maintenance of PMN function in the periodontal pocket. J Periodontol 1999;70:179‐184.
Effects of Cyclosporin A on Alveolar Bone: An Experimental Study in the Rat
Authors: Fu Earl , Hsieh Yao‐Dung , Nieh Shin , Wikesjö Ulf M.E. , Liu Demeral
Published: February 2005

Background: There have been several investigations on the role of cyclosporin A (CSA) in gingival hyperplasia in both animals and humans. However, less attention has been given to the drug's effect on alveolar bone. This study used light microscopy to histologically and histometrically evaluate the effects of CSA on alveolar bone in the rat.

Methods: Sixty, 6‐week‐old Sprague‐Dawley rats were separated into test and control groups. Animals in the test group received CSA in mineral oil (30 mg/kg body weight) daily by gastric feeding over the 6‐week study. Control animals received only mineral oil. Ten animals from each group were sacrificed at weeks 2, 4, and 6. After histologic processing, the labial crest of the alveolar bone in the anterior mandible was evaluated by light microscopy.

Results: A distinct pattern of increased osteoclasia and reduced bone formation was observed in the CSA‐exposed animals compared to the controls. Increased osteoclasia was observed in periodontal sites and decreased bone formation was observed in symphyseal sites.

Conclusions: The results suggest that CSA has distinct effects on alveolar bone. J Periodontol 1999;70:189‐194.
A Long‐Term Evaluation of Composite‐Bonded Natural/Resin Teeth as Replacement of Lower Incisors With Terminal Periodontitis
Authors: Quirynen Marc , Mongardini Claudio , Lambrechts Paul , De Geyseleer Caroline , Labella Roberto , Vanherle Guido , van Steenberghe Daniel
Published: February 2005

Background: In patients with svere peridontitis, lower incisors are prone to terminal reakdown. This study assessed the longevity of composite‐bonded resin/natural teeth (reinforced only with a stainless steel mesh) as replacements for periodontally lost lower incisors.

Methods: Besides the longevity of the restoration, the periodontal condition of the abutment teeth, and the general satisfaction of the patient were evaluated retrospectively via a phone interview, in combination with an analysis of the patient's clinical dental file.

Results: The cumulative proportion of survival rate of these composite restorations was 80% after 5 years of function. No statistically significant difference was found between the survival distribution of one‐ and two‐pontic bridges (P = 0.66). The abutment teeth demonstrated stable probing depths and a negligible loss in attachment (0.1 mm/year). The satisfaction ratings were also favorable.

Conclusions: The data seem to suggest that composite bonding of 1 or 2 teeth can be considered a semi‐permanent rehabilitation for the replacement of 1 or 2 periodontally lost lower incisors. J Periodontol 1999; 70: 205‐212.
Periodontal Bacteria in Adult Twins
Authors: Michalowicz Bryan S. , Wolff Larry F. , Klump David , Hinrichs James E. , Aeppli Dorothee M. , Bouchard Thomas J. , Pihlstrom Bruce L.
Published: February 2005

Background: Both environmental and genetic factors are known to influence clinical measures periodontal disease. The purpose of this study was determine whether genetic factors similarly influence the presence of specific periodontal bacteria in subgingival plaque.

Methods: Reared‐together and reared‐apart monozygous (MZ) and dizygous (DZ) adult twins were examined clinically. Demographic and behavioral information was obtained from each subject by questionnaire. Subgingival plaque samples were obtained from the index teeth, and the presence of P. intermedia, P. gingivalis, A. actinomycetemcomitans, E. corrodens, and F. nucleatum was determined using an immunoassay.

Results: Microbiological and clinical data were available for 169 twin pairs. The subject‐based prevalences of the bacteria in the twin groups ranged from 11% for Porphyromonas gingivalis to 40% for F. nucleatum. For all species examined, the concordance rates were not significantly different (P > 0.05) between MZ and DZ twin groups. These findings were apparent despite similar smoking histories, self‐reported oral hygiene practices, and antibiotic use in the twin groups. Furthermore, MZ twins reared together were not more similar than MZ reared‐apart twins with respect to any bacterial species examined.

Conclusions: These findings suggest that in a population with access to routine dental care, any effects that host genes and the early family environment have on the presence of specific bacteria in subgingival plaque are not apparent in adulthood. Most twins with disease in this study had early periodontitis. Results from this study may not necessarily be extrapolated to more advanced disease states. J Periodontol 1999;70:263‐273.
The Effect of Stress on the Inflammatory Response to Porphyromonas gingivalis in a Mouse Subcutaneous Chamber Model
Authors: Shapira Lior , Houri‐Haddad Yael , Frolov Igor , Halabi Amal , Ben‐Nathan David
Published: February 2005

Background: The impact of emotional stress on the outcome of infectious diseases was studied in animal models and humans, but data related to the effect of stress on periodontal infection are limited. Using the subcutaneous chamber model in mice, the present study was carried out to investigate the effect of stress on the host response to Porphyromonas gingivalis.

Methods: Mice with subcutaneous chambers (2 per animal) were divided into 4 treatment groups: cold‐stress; isolation‐stress; corticosterone (CS)‐injected; and controls. On the third day of stress conditions, heat‐killed P gingivalis were injected into the chambers. The chambers were sampled 1 and 5 days later and analyzed for leukocyte number, tumor necrosis factor (TNF)‐ α levels, and interferon (IFN)= γ levels.

Results: injection of P gingivalis induced the migration leukocytes into the chambers and increased the intrachamber levels of IFN‐ γ and TNF‐ α . There were no significant differences in cell number and IFN‐ γ levels between the different treatment groups, but the levels of TNF‐ α were significantly lower in the isolation‐stress and cold‐stress groups compared to control animals. CS‐injected animals were not different from controls. In addition, the levels TNF‐ α in the stressed animals were lower on the fifth day post‐injection than on the first day, but not in the CS and control group.

Conclusions: The results suggest that the levels of TNF‐ α induced by P. gingivalis in the infection site are downregulated in stressed animals, and CS is not the sole mediator responsible. The stress‐induced reduction in TNF‐ α levels might have an impact on the pathogenesis of periodontal disease in humans experiencing emotional stress. Periodontol 1999;70:289‐293.
Cyclosporin A Regulates Interleukin‐1ßand Interleukin‐6 Expression in Gingiva: Implications for Gingival Overgrowth
Authors: Myrillas Theofilos T. , Linden Gerard J. , Marley John J. , Irwin Chris R.
Published: February 2005

Background: Gingival overgrowth is a common side effect following the administration of cyclosporin A (CsA); however, the cellular mechanisms remain poorly understood. CsA's immunosuppressant properties involve the regulation of synthesis and cellular response to cytokines. A CsA‐induced alteration in the cytokine profile within gingival tissue could provide a mechanism for gingival hyperplasia. The aim of this study was to investigate the effects of CsA on the production of 2 cytokines — interleukin‐1ß(IL‐1ß) and interleukin‐6 (IL‐6) — by both gingival fibroblasts and peripheral blood mononuclear cells (PBMC).

Methods: Cells were stimulated for 24 hours in the presence of CsA over a concentration range of 100 to 2,000 ng/ml and the resultant cytokine production determined by ELISA. In addition, levels of both cytokines within normal, inflamed, and overgrown gingival tissue were determined.

Results: CsA inhibited IL‐6 production by gingival fibroblasts in a dose‐dependent manner. In contrast, at a concentration of 2,000 ng/ml, CsA stimulated IL‐6 production by PBMC ( P< 0.05). Fibroblasts derived from overgrown gingiva produced significantly higher levels of IL‐6 than their normal counterparts ( P <0.05). CsA inhibited IL‐1ßproduction by PBMC over the whole concentration range ( P <0.05). IL‐1ßwas not found in measurable quantities in any of the fibroblast cultures. Levels of IL‐6 extracted from overgrown gingival tissue were significantly higher than in inflamed or normal tissue. In contrast IL‐1ßlevels in overgrown tissue were not statistically significantly greater than those in inflamed tissue.

Conclusions: These results show that CsA does regulate cytokine expression in gingival tissue. This effect may play an important role in the pathogenesis of CsA‐induced gingival overgrowth. J Periodontol 1999;70:294‐300.
Site‐Specific Attachment Level Change Detected by Physical Probing in Untreated Chronic Adult Periodontitis: Review of Studies 1982‐1997
Authors: Breen Harry J. , Johnson Newell W. , Rogers Pauline A.
Published: February 2005

Background: Site‐specific attachment level change, detected from sequential physical probing measurements, is currently the most common method of determining the progression/regression or stability of disease status in subjects with chronic adult periodontitis. The sensitivity and accuracy of detection is dependent on the type of probe used, the recording method, the measurement error, and the method of data analysis. In recent years, there has been world‐wide interest in developing instruments and methods to minimize measurement error. Published data report disturbingly wide variation in the prevalences and rates of site‐specific attachment level change which are difficult to reconcile with biological likelihood. The present paper aims to summarize the salient points from the key studies and to compare the results.

Methods: The literature between 1982 and 1997 was reviewed for studies in which site‐specific attachment level change was detected by physical probing methods in patients with chronic adult periodontitis. Results: The review documents 23 studies by probe generation, to the thresholds and probe type used. The 23 studies used an array of probe types from the 3 probe generations. compares methods and results and summarizes the results according

Results: The review documents 23 studies by probe generation, to the thresholds and probe type used. The 23 studies used an array of probe types from the 3 probe generations. compares methods and results and summarizes the results according

Conclusions: From this review, we conclude that: 1) There are surprisingly few papers which have addressed the question of site‐specific attachment level change in untreated chronic adult periodontitis. 2) There are considerable differences in the probes used, in the thresholds achieved, in the number of measurements taken, in the number of subjects and sites studied, and in the duration of the studies. Valid comparisons between studies are, therefore, rarely possible. 3) Only out of 23 papers from 1982 to 1997 have adequate data. Most papers report only losing sites and therefore ignore many of the measurements recorded. Only one paper describes losing sites, gaining sites, and sites showing exacerbation/remission patterns of change. 4) The range of changes described show such variation that it has to be concluded that we cannot reliably detect site‐specific attachment level change by physical probing and thus, at the end of the 20th century, we have no clear idea of the natural history of this disease. J Periodontol 1999;70:312‐328.
Palatal Tubercles, Palatal Tori, and Mandibular Tori: Prevalence and Anatomical Features in a U.S. Population
Authors: Sonnier Keith E. , Horning Gregory M. , Cohen Mark E.
Published: February 2005

The prevalence and features of 3 types of exostoses commonly encountered during periodontal surgery were studied in a sample of 328 modern American skulls drawn from the collection at the American Museum of Natural History. Measurements were made of the height, width, and breadth of exostoses. The relationship to teeth or other skeletal structures was also recorded. Palatal tubercles were observed in 56% of all skulls (69% of all dentate skulls), with higher prevalences among males and African‐Americans. Palatal tubercles were commonly associated with second and third molars, and were usually directly lateral to and a mean of 11.4 mm from the greater palatine foramen. Mandibular tori were observed in 27% of all skulls (42% of dentate skulls), with higher prevalences seen among African‐Americans and males. The importance of these findings relates to the frequent need for exostosis removal to permit proper flap adaptation, especially in the posterior maxilla, and to the potential use of the mandibular and palatal tori as sources of autogenous cortical bone. J Periodontol 1999;70:329‐336.
Bacteriostatic Effects of Hyaluronic Acid
Authors: Pirnazar Payman , Wolinsky Larry , Nachnani Sushma , Haake Susan , Pilloni Andrea , Bernard George W.
Published: February 2005

Background: This investigation is one of a series of projects seeking to ascertain whether hyaluronic acid (HA) is therapeutically effective in tissue regeneration procedures. The rationale for these investigations is to test the hypothesis that HA can serve as a bioabsorbable carrier for other substrates as well as itself actively promote the regeneration of tissue.

Methods: In this paper, we report on the bacteriostatic and bactericidal properties of 3 molecular weight formulations of recombinant HA (low, 141 kD; medium, 757 kD; and high, 1,300 kD) on selected oral and non‐oral microorganisms in the planktonic phase. Three concentrations of each HA formulation were screened, 0.5, 1.0, and 2.0 mg/ml, using a standard broth culture assay.

Results: Recombinant HA exerted varied bacteriostatic effects on all the bacterial strains tested depending on its molecular weight (MW) and concentration. The high concentrations of the medium MW HA had the greatest bacteriostatic effect, particularly on the Actinobacillus actinomycetemcomitans, Prevotella oris, Staphylococcus aureus, and Propionibacterium acnes strains. The 1.0 mg/ml concentration of high MW HA had the greatest overall bacteriostatic effect, inhibiting the growth of all 6 bacterial strains tested. Among the bacterial strains studied, HA was found to have no bactericidal effects, regardless of concentration or molecular weight.

Conclusions: The results of this study suggest that HA in the MW range of 1,300 kD may prove beneficial in minimizing bacterial contamination of surgical wounds when used in guided tissue regeneration surgery. J Periodontol 1999;70:370‐374.
A New Injectable Calcium Phosphate Biomaterial for Immediate Bone Filling of Extraction Sockets: A Preliminary Study in Dogs
Authors: Gauthier Olivier , Boix Damien , Grimandi Gaël , Aguado Eric , Bouler Jean‐Michel , Weiss Pierre , Daculsi Guy
Published: February 2005

Background:
Many different bone substitutes, such as autografts, allografts or synthetic biomaterials have been proposed to restore alveolar bone loss and support efficient placement of dental implants. This experimental study evaluated the osteoconductive properties of an injectable bone substitute (IBS) composed of a polymeric carrier and a calcium phosphate mineral phase, used to fill mandibular and maxillary canine extraction sockets.

Methods:
The polymer was a cellulose derivative (methyl‐hydroxy‐propyl‐cellulose, MHPC), and the mineral phase consisted of granules of biphasic calcium phosphate (BCP) ceramics 200 to 500 μm in diameter. Mandibular and maxillary premolars extracted from 3 dogs (a total of extraction sites) were immediately treated with the IBS left unfilled as control sites. Animals were sacrificed months after implantation and all extraction sockets were prepared for histological evaluation.

Results:
Qualitative histological studies showed that the IBS was able to support the extensive apposition of wellmineralized newly formed lamellar bone over the entire socket surface and appeared to prevent alveolar ridge bone loss in treated extraction sites. Quantitative evaluation showed that the amount of newly formed bone was significantly higher in mandibular than maxillary extraction sockets for both treated and control sites.

Conclusions:
An injectable bone substitute composed of a polymeric carrier and calcium phosphate was effective in enhancing the bone fill of extraction sockets. This approach may prove promising for periodontal lesions. The material expressed osteoconductive capacities, and the biological properties of the mineral phase were conserved. J Periodontol 1999;70:375‐383.
Monoclonal Antibodies Against Integrin Subunits α6 and β1 Inhibit Migration of Gingival Epithelium in Organ Culture
Authors: Gräber Hans‐Georg , Wilharm Jens , Conrads Georg
Published: February 2005

Background: The main problem in the posterior instrumental treatment of periodontitis is the re‐epithelization of the periodontal defects, leading to the formation of an unphysiological, long junctional epithelium inhibiting the regeneration of periodontal attachment. A precondition for the re‐epithelization is the interaction between epithelial cells and their extracellular matrix mediated by integrins. Integrins are cellular adhesion molecules (CAM), binding to different structures of the extracellular matrix, e.g., collagen, laminin, or fibronectin.

Methods: Biopsy specimens of marginal gingiva, composed of epithelium and subepithelial connective tissue, were cultivated on microporous membranes in tissue culture plates. The culture medium was supplemented with monoclonal antibodies directed against human integrin subunits. The period of cultivation was 6 days and the medium was replaced daily. After cultivation, the tissue development was analyzed by histological and immunohistochemical methods.

Results: We found that the combination of antibodies directed against the integrin subunits α6 and β1 inhibited the migration of epithelium completely in 9 out of 10 cultures, whereas control cultures containing none or only irrelevant antibodies demonstrated connective tissues completely covered by epithelium.

Conclusions: Influencing the regeneration of periodontal tissue on a molecular basis by using antibodies directed against integrin subunits may be of future interest in postsurgical treatment of periodontal diseases. J Periodontol 1999;70:388‐393.
Increase of Urokinase‐Type Plasminogen Activator Receptor Expression in Human Gingival Fibroblasts by Porphyromonas gingivalis Lipopolysaccharide
Authors: Ogura Naomi , Nagura Hideaki , Abiko Yoshimitsu
Published: February 2005

Background: Urokinase‐type plasminogen activator receptor (uPAR) presenting on the cell surface with glycosylphosphatidylinositol (GPI) anchor is a key component in the plasminogen activator (PA)‐plasmin system and plays a critical role in extracellular matrix degradation. It is believed that uPAR serves to localize and accelerate this generation system. In this study, we examined the levels of both uPA and uPAR in human gingival fibroblasts treated with Porphyromonas gingivalis lipopolysaccharide (LPS).

Methods: Human gingival fibroblasts from the seventh to tenth doubling passages were plated at 5 x 104 cells per well in 24‐well plates. The confluent‐stage cells were cultured for 24 hours in α‐MEM medium containing 2% fetal calf serum, after which they were incubated with P. gingivalis LPS. PA activity was measured using plasminogen and plasmin substrate S2251.

Results: PA activity in the cell lysate was increased by LPS and reached maximum at 1 μg/ml LPS after being incubated for 8 hours. PA activity released by phosphatidylinositol‐specific phospholipase C, which detaches the GPI anchor, was also increased by LPS. The activity was inhibited by amiloride, which is a specific inhibitor for uPA. LPS increased the protein and mRNA levels of both uPA and uPAR in gingival fibroblasts.

Conclusions: These findings suggest that increase of the uPAR level by LPS may play an important role in the progression of periodontal diseases through pericellular proteolysis. J Periodontol 1999;70:402‐408.
Retained Free Gingival Graft Rugae: A 9‐Year Case Report
Authors: Breault Lawrence G. , Fowler Edward B. , Billman Michael A.
Published: February 2005

In the oral cavity, masticatory mucosa covers the hard palate and gingiva. The epithelium of masticatory mucosa is relatively thick compared to other oral tissues. This results in firmness and immobility necessary to withstand the forces of mastication. In the anterior aspect of the hard palate, long papillae within the lamina propria and thick dense collagenous tissue are found under the transverse ridges or rugae. Though palatal rugae are generally avoided during soft tissue grafting, there are few literature references detailing the consequences of transplanting tissue from the anterior palate which contains rugae. The following case report describes retained palatal rugae in a free gingival graft, which had been transplanted to an edentulous ridge 9 years earlier. J Periodontol 1999;70:438‐440.
Gingival Metastasis From a Prostate Adenocarcinoma: Report of a Case
Authors: Piattelli A. , Fioroni M. , Rubini C.
Published: February 2005

Prostate cancer is the cause of 10% of cancer‐related deaths in males in the United States. Metastases are found late in the course of the disease. Metastatic tumors of the oral cavity are rare, representing about 1% of oral tumors and affect jaws much more frequently than soft tissues. Metastatic pr ostate cancer tends to involve the bones of the axial skeleton. In a recent review, 22 cases of metastases to the jawbones from prostate cancer were found in 390 cases. On the other hand, only 1 case of a metastasis to the oral soft tissues was reported. The authors describe the second case of oral soft tissue metastasis from a prostate cancer. The metastatic lesion was located in the gingiva. Clinicians should be aware of oral soft tissue metastases since they can be the first sign of a not yet diagnosed malignant tumor and they can be very easily confused with several dif ferent benign lesions. J Periodontol 1999;70:441‐444.
Single Tooth Replacement of Missing Molars: A Retrospective Study of 78 Implants
Authors: Schwartz‐Arad Devorah , Samet Naama , Samet Nachum
Published: February 2005

As experience with osseointegrated implants has grown, greater use has been made of placement in the posterior jaw. The aim of this study is to present the survival rate of 78 osseointegrated single implants, inserted in the molar area and to evaluate the prosthetic rehabilitation on these teeth. This retrospective study presents findings of 55 consecutive patients with 78 restored single osseointegrated implants in the molar area. The patients went through a clinical and radiological evaluation. The same maxillofacial surgeon inserted all implants. Three of the implants were inserted into the maxilla and 75 into the mandible; 4 of the 78 implants were immediate implants. The cumulative survival rate after one year was 93.6%. Follow‐up was up to 80 months, with an average of 27 months. Out of all the implants, 6 failed (7.7%): 5 failed in the surgical stage, and 1 after prosthetic loading. The main implant failures were among the titanium screw implants. Prosthetic complications occurred in 11 cases (14%), which included loosening of the abutment and/or the crown (9 cases), fracture of the abutment (1 case), and porcelain fracture (1 case). No incident of implant fracture occurred. Within the limits of this study, replacement of a single molar by a single implant is a valid and successful surgical treatment modality, with a high survival rate. J Periodontol 1999;70:449‐454.
The Relationship Between Oral Malodor, Gingivitis, and Periodontitis. A Review
Authors: Ratcliff Perry A. , Johnson Paul W.
Published: February 2005

Volatile sulfur compounds (VSC) are a family of gases which are primarily responsible for halitosis, a condition in which objectionable odors are present in mouth air. Although most patients perceive this condition as primarily a cosmetic problem, an increasing volume of evidence is demonstrating that extremely low concentrations of many of these compounds are highly toxic to tissues. VSC may, therefore, play a role in the pathogenesis of inflammatory conditions such as periodontitis. Since these compounds result from bacterial putrefaction of protein, investigations have been conducted to determine whether specific bacteria are associated with odor production. Two members of this family, hydrogen sulfide (H2S) and methyl mercaptan (CH3SH), are primarily responsible for mouth odor. Although many bacteria produce H2S, the production of CH3SH, especially at high levels, is primarily restricted to periodontal pathogens. Direct exposure to either of these metabolites adversely affects protein synthesis by human gingival fibroblasts in culture. However, methyl mercaptan has the greatest effect. Other in vitro experiments have demonstrated that cells exposed to methyl mercaptan synthesize less collagen, degrade more collagen, and accumulate collagen precursors which are poorly cross‐linked and susceptible to proteolysis. CH3SH also increases permeability of intact mucosa and stimulates production of cytokines which have been associated with periodontal disease. VSC, and in particular methyl mercaptan, are therefore capable of inducing deleterious changes in both the extracellular matrix and the local immune response of periodontal tissues to plaque antigens. This article reviews these data and emphasizes the potential importance of VSC in the transition of periodontal tissues from clinical health to gingivitis and then to periodontitis. J Periodontol 1999;70:485‐489.
Persistence of Oral Colonization by the Same Actinobacillus actinomycetemcomitans Strain(s)
Authors: Saarela Maria H. , Doğan Başak , Alaluusua Satu , Asikainen Sirkka
Published: February 2005

Background: The Gram‐negative facultatively anaerobic coccobacillus Actinobacillus actinomycetemcomitans is the major pathogen in localized juvenile periodontitis (LJP) and some forms of adult periodontitis (AP). A. actinomycetemcomitans can be grouped into 5 serotypes (a through e) based on differences in the carbohydrate moiety of cell surface lipopolysaccharide. The A. actinomycetemcomitans population is genetically heterogeneous. Since the studies on A. actinomycetemcomitans colonization have mostly applied only culture techniques, the clonality of the follow‐up isolates has not been established. Thus, it is possible that, although A. actinomycetemcomitans could be repeatedly isolated from an individual, the intitial colonizing strain was replaced by another strain. The aim of the study was to determine whether oral A. actinomycetemcomitans strains change spontaneously over time or after periodontal treatment.

Methods: A total of 922 A. actinomycetemcomitans isolates were recovered from 115 subjects. From each subject A. actinomycetemcomitans isolates were obtained from 2 to 9 follow‐up samples 0.5 to 11.5 years apart. After the first sampling occasion, 99 subjects were treated for either LJP or AP, whereas the 16 non‐periodontitis subjects received no treatment. All A. actinomycetemcomitans isolates were serotyped and 235 isolates from 52 subjects genotyped with AP‐PCR and/or with ribotyping.

Results: Isolates of only one serotype, or non‐serotypeable isolates alone, were repeatedly found in 104 subjects; serotype a occurred in 25%, b in 33%, c in 23%, d in 5%, e in 7%, and non‐serotypeable isolates in 8% of these subjects. Two serotypes (or serotypeable isolates together with non‐serotypeable isolates) occurred simultaneously in 9 subjects and in each of these subjects at least one of the serotypes was detected at each sampling occasion. In one subject the initial serotype reappeared although a different serotype was once seen alone, whereas in another subject the initial serotype could not be recovered later. Identical genotypes of A. actinomycetemcomitans were repeatedly detected in each of 52 subjects with follow‐up isolates of the same serotype.

Conclusions: The results showed that spontaneous or treatmentinduced change in the oral A. actinomycetemcomitans strain(s) is extremely rare and that colonization with the same strain(s) seems to be remarkably persistent. J Periodontol 1999;70:504‐509.
Effects of Tobacco Products on the Attachment and Growth of Periodontal Ligament Fibroblasts
Authors: James Jacqueline A. , Sayers Nicola M. , Drucker David B. , Hull Peter S.
Published: February 2005

Background: Cigarette smoking is one of the most significant risk factors in the development and further advancement of inflammatory periodontal disease, however, the role of either nicotine or its primary metabolite cotinine in the progression of periodontitis is unclear. This study aimed to investigate the effects of nicotine and cotinine on the attachment and growth of fibroblasts derived from human periodontal ligament (PDL).

Methods: Primary cultures were prepared from the roots of extracted premolar teeth. Cells were used at both low (P3 to P5) and high (P11 to P13) passage. Cell numbers were determined over 14 days using either the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2, 5‐diphenyl tetrazolium bromide (MTT) assay or with a Coulter counter. Cultures were exposed to culture medium supplemented with 1) 15% fetal calf serum (FCS) only; 2) 1% FCS only; 3) 1% FCS and nicotine (concentration range 5 ng/ml to 10 mg/ml); or 4) 1% FCS and cotinine (concentration range 0.5 ng/ml to 10 µg/ml).

Results: Nicotine significantly (P <0.05, by ANOVA) inhibits attachment and growth of low passage cells at concentrations >1 mg/ml and high passage PDL fibroblasts at concentrations >0.5 mg/ml. Cotinine, at the highest concentration used (10 µg/ml), appeared to inhibit attachment and growth of both low and high passage fibroblasts but this was not statistically significant (P >0.05, by ANOVA).

Conclusions: Tobacco products inhibit attachment and growth of human PDL fibroblasts. This may partly explain the role of these substances in the progression of periodontitis. J Periodontol 1999;70:518‐525.
CREST Syndrome and Periodontal Surgery: A Case Report
Authors: Stanford Thomas W. , Peterson Jill , Machen Robert L.
Published: February 2005

CREST syndrome is a slowly progressive form of systemic scleroderma. It is characterized by calcinosis cutis, Raynaud's phenomenon, esophageal involvement, sclerodactyly, and telangiectasia. There are limited reports of dental treatment for patients with this syndrome, and no reports of periodontal surgical procedures. This paper presents a case report of periodontal surgical treatment in a 38‐year‐old female patient with CREST syndrome, and a discussion of the clinical manifestations of the syndrome as they relate to dental treatment. J Periodontol 1999;70:536‐541.
Polymer‐Assisted Regenerative Therapy: Case Reports of 22 Consecutively Treated Periodontal Defects With a Novel Combined Surgical Approach
Authors: Rosen Paul S. , Reynolds Mark A.
Published: February 2005

This report describes the clinical application of an in situ formed barrier of poly(DL‐lactide) used in combination with a composite graft of demineralized freezedried bone allograft (DFDBA) mixed with calcium sulfate and tetracycline in a ratio of 7:2:1 and citric acid root conditioning for the treatment of intrabony and furcation defects. The clinical outcome was assessed by changes in clinical attachment level (CAL) and probing depth (PD) in 18 consecutively treated patients with 17 intrabony and 5 furcation lesions. After patients demonstrated acceptable oral hygiene, the lesions were surgically treated with combination therapy using an in situ formed barrier over a DFDBA composite graft. Patients followed a stringent postoperative protocol and were evaluated at 6 months postsurgery. CAL improved for all sites from a presurgical average of 8.8 ± 2.3 mm to 4.4 ± 1.6 mm at 6 months postsurgery (4.4 ± 1.5 mm gain), while PD was reduced from an average of 8.3 ± 2.1 mm presurgery to 3.3 ± 1.1 mm at 6 months postsurgery (5.0 ± 1.8 mm reduction). Five furcations were treated, of which 4 were Class II and 1 was Class III. Of these furcation lesions, 3 had complete clinical closure, while 1 improved by 1 grade. The Class III furcation remained the same. Results suggest that DFDBA composite graft covered by an in situ formed barrier on root surfaces treated with citric acid can enhance the prognoses of teeth with periodontal lesions as measured by CAL gains and PD reductions. Further studies are warranted to compare this treatment to other more traditional forms of regenerative therapy to determine its comparative efficacy. J Periodontol 1999;70:554‐561.
Expression of p53 Protein and Ki‐67 Antigen in Gingival Hyperplasia Induced by Nifedipine and Phenytoin
Authors: Saito Keiichi , Mori Shiro , Tanda Naoko , Sakamoto Seizaburo
Published: February 2005

Background: Although it has been thought that drug‐induced gingival hyperplasia is not related to tumorigenesis, recent case reports have shown that squamous cell carcinomas may arise in gingival hyperplasia induced by cyclosporin and phenytoin. The possible implications between the pathogenesis of this disease and tumorigenesis have not been elucidated and remain to be studied.

Methods: We immunohistochemically examined the expression of tumor‐related markers such as p53 protein and Ki‐67 antigen in 11 hyperplastic gingival tissues induced by nifedipine and phenytoin, as well as 5 control tissues using an avidin‐biotin‐peroxidase complex method.

Results: Two specimens out of 4 nifedipine‐induced and 4 out of 7 phenytoin‐induced hyperplastic gingival tissues revealed the expression of p53protein in the nuclei of epithelial cells, while no expression of p53 protein was observed in the epithelia of the 5 non‐hyperplastic control tissues. The immunoreactions against p53 protein showed sporadic distribution in the suprabasal layers of hyperplastic epithelia. The mean percentage of epithelial cells expressing Ki‐67 antigen in the hyperplastic gingival tissues was more than 10% higher than that in the controls. The expression of Ki‐67 antigen was suppressed in the typical rete pegs deeply elongated into lamina propria of hyperplastic gingival tissues. Intense immunostaining of Ki‐67 antigen was found in fibroblasts of hyperplastic gingival tissues, while that of the control tissues was negligible.

Conclusions: The expression of p53 protein in gingival hyperplasia suggests that the pathogenesis of this disease is involved with impaired DNA, while the growth arrest observed in the hyperplastic epithelia with typically elongated rete pegs as expressed with Ki‐67 antigen may prevent the invasive expansion of epithelial cells undergoing DNA damage within gingival tissues and may consequently suppress tumorigenic progression. J Periodontol 1999;70:581‐586.
In Vitro Stimulation of Human Gingival Epithelial Cell Attachment to Dentin by Surface Conditioning
Authors: Vanheusden Alain J. , Goffinet Gérhard , Zahedi Sharam , Nusgens Betty , Lapiére Charles M. , Rompen Eric H.
Published: February 2005

Background: Chemical root conditioning is widely used to improve the outcome of regenerative periodontal therapies by favoring the attachment of the regenerated periodontal structures. Although the effect of root conditioning on periodontal mesenchymal cells is well documented, very little is known about its potential effect on the re‐formation of the junctional epithelium, a crucial event for the protection of the wound. The goal of the present study was to test in vitro the consequences of dentin conditioning with citric acid or minocycline on the attachment kinetics and morphology of human gingival keratinocytes (HGK).

Methods: The attachment kinetics of HGK to samples of powdered human dentin (particle size 44 to 76 µm) were examined by use of 3H‐labeled cells. The morphology of attached epithelial cells was then determined by scanning electron microscopy (SEM).

Results: When the initial adhesion kinetics of cells on untreated dentin were tested, the percentage of attached HGK proved to be dependent on the number of plated cells and the time of incubation from 0 to 12 hours). Conditioning the dentin by 3% citric acid or by minocycline‐HCl (at 0.01, 0.1, or 2.5%) significantly increased (P <0.005) keratinocyte attachment beyond 6 hours, without notable differences between the 2 substances at any concentration. The attachment kinetics of HGK preincubated for 24 hours by 10 µg/ml minocyline‐HCl on untreated dentin was found to be similar to that observed for non‐preincubated cells. These results are in agreement with the SEM observations: indeed, the surface conditioning of dentin significantly modified the morphology of attached HGK, whereas the preincubation of these cells with minocyline‐HCl did not.

Conclusions: These results suggest that minocycline‐HCl does not exert a direct effect on human gingival epithelial cells. In contrast, conditioning the dentin by citric acid or by minocycline stimulates the attachment of HGK, which could lead to a rapid periodontal healing by favoring the re‐formation of a junctional epithelium. J Periodontol 1999;70:594‐603.
Androgens Modulate Interleukin‐6 Production by Gingival Fibroblasts In Vitro
Authors: Gornstein Russell A. , Lapp Carol A. , Bustos‐Valdes Sergio M. , Zamorano Pedro
Published: February 2005

Background: Pregnancy and puberty gingivitis have been attributed to increased concentrations of circulating sex hormones. This inflammatory gingival condition is accompanied by the local production of cytokines. The aims of this in vitro study were to assess, in the presence or absence of testosterone (T) or dihydrotestosterone (DHT), the production of interleukin‐6 (IL‐6) by human gingival fibroblasts (hGF), and to evaluate the effects of flutamide (a common anti‐androgen) in this system.

Methods: The effects of the androgens, T and DHT, on IL‐6 production were measured in vitro in serum‐free, phenol red‐free medium. Cells were incubated with or without androgens for 72 hours; the concentration of IL‐6 secreted into the medium after an additional 24‐hour challenge with IL‐1β plus hormones was estimated by radioimmunoassay. The reverse transcription polymerase chain reaction was used to examine hGF and periodontal ligament cells (PDL) for the presence of androgen receptor.

Results: In serum‐free medium, T and DHT at concentrations of 5 x 10‐8 to 10‐7M significantly (P <0.05) inhibited IL‐6 production by hGF. Flutamide, up to concentrations of 2 x 10‐5M, did not reverse this inhibition. The androgen receptor was identified in both hGF and PDL.

Conclusions: We concluded that elevated levels of androgens, specifically testosterone and dihydrotestosterone, could affect the stromal cell response to an inflammatory challenge by downregulation of IL‐6 production. This in vitro study lends support to the hypothesis that increased hormones during pregnancy or puberty could modulate the development of localized inflammation. J Periodontol 1999;70:604‐609