bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effect of Recombinant Human Bone Morphogenetic Protein‐4 on the Osteoblastic Differentiation of Mouse Calvarial Cells Affected by Porphyromonas gingivalis
Authors: Kim Chang‐Sung , Choi Seong‐Ho , Choi Bong‐Kyu , Chai Jung‐Kiu , Park Joon‐Bong , Kim Chong‐Kwan , Cho Kyoo‐Sung 
Published: February 2005

Background: A number of studies have shown effective bone regeneration induced by bone morphogenetic proteins (BMPs), but it is not clear whether the presence of periodontopathic bacteria has any significant modulation effect on the bone regeneration ability of BMPs. The present study examined whether pretreatment of mouse calvarial cells with Porphyromonas gingivalis extracts can make a difference in their osteoblastic differentiation exerted by recombinant human bone morphogenetic protein‐4 (rhBMP‐4).Methods: Primary mouse calvarial osteoblastic (MCO) cells were cultured until they reached confluence. At confluence, cells were untreated or pretreated with 1 µg/ml of sonicated P. gingivalis extracts (SPEs) for 2 days. After washing, the cells were further incubated in the presence of rhBMP‐4 (0 to 100 ng/ml) for 3 days. At the end of the treatment, the cells were harvested and lysed for measurement of the alkaline phosphatase (ALP) activity. Total RNA was extracted, and reverse transcription‐polymerase chain reaction (RTPCR) analysis for expression of ALP mRNA was conducted. The amount of prostaglandin E2 (PGE2) secreted into the culture supernatant was determined using an enzyme immunoassay.Results: The stimulatory effect of rhBMP‐4 on ALP activity was observed in both untreated MCO cells and in cells pretreated with 1 µg/ml of SPEs in a dose‐dependent manner. The ALP activities were signifi‐cantly reduced in the cells pretreated with SPEs at all concentrations of rhBMP‐4 used in the study when compared to untreated cells. Similar results were obtained in the RT‐PCR analysis for ALP mRNA. Cells pretreated with SPEs released significantly larger amounts of PGE2 than untreated cells, but the treatment with 100 ng/ml of rhBMP‐4 had no significant effect on the amount of PGE2 released. These results suggest that the stimulatory effect of rhBMP‐4 on osteoblastic differentiation might be significantly reduced by P. gingivalis, possibly through the endogenous PGE2 pathway, but rhBMP‐4 still has a stimulatory effect on osteoblastic differentiation of mouse calvarial cells affected by P. gingivalis.Conclusion: Our results suggest that supplemental BMPs would be beneficial for improved treatment of osseous defects, although their biologic effect might be significantly reduced by periodontopathic bacteria. J Periodontol 2002;73:1126‐1132.
Bone Regeneration of Localized Chronic Alveolar Defects Utilizing Cell Binding Peptide Associated With Anorganic Bovine‐Derived Bone Mineral: A Clinical and Histological Study
Authors: Barboza Eliane Porto , de Souza Rogério Oliveira , Caúla André Luis , Neto Luiz Geolás , de Oliveira Caúla Fernanda , Duarte Maria Eugênia Leite 
Published: February 2005

Background: Osteoinduction to treat osseous defects has been attempted by several means. Some clinical studies have demonstrated that a synthetic cell binding peptide (P‐15) with anorganic bovine derived bone matrix (ABM) has the ability to enhance bone regeneration. These studies suggest that more histological data are necessary to better understand this process. We have developed a Class III chronic alveolar defect animal model to investigate space‐maintaining regenerative materials. The objective of this study was to clinically and histologically evaluate the use of P‐15/ABM with or without a bioabsorbable membrane (M) to regenerate localized chronic alveolar ridge defects in dogs.Methods: Six adult, male mongrel dogs were used in this study. Bilateral, Class III, alveolar defects were surgically produced following extraction of the mandibular second premolar teeth and local reduction of the alveolar ridge. After an 8‐week healing interval, mucoperiosteal flaps were elevated. P‐15/ABM with or without bioabsorbable membranes were implanted into contralateral defects in 10 sites. Two sites received no biomaterial (controls). Mucoperiosteal flaps were advanced over the P‐15/ABM or P‐15/ABM/M constructs and sutured. Pre‐ and postaugmentation clinical evaluation was done utilizing periodontal probes and calipers. The animals were sacrificed 12 weeks postaugmentation and block specimens processed for histologic evaluation.Results: Clinical results showed no significant statistical augmentation on the control group (0.0 ± 0.6 mm). In all experimental sites utilizing P‐15/ABM or P‐15/ABM/M, relevant ridge augmentation was observed (3.6 ± 2.0 mm and 2.9 ± 1.9 mm, respectively). Histologically, all experimental sites showed active bone formation with plump osteoblast and osteoid matrix deposition in the treated area. Bone ingrowth filled the area of the defects treated with P‐15/ABM/M. Few P‐15/ABM particles were seen in the cellular fibrous tissue surrounding the new formed bone trabeculae.Conclusions: P‐15/ABM with or without membranes can produce a significant clinical ridge augmentation. Bone formation was histologically observed in all test areas. The association of a membrane with P‐15/ABM seemed to enhance the process of bone formation. J Periodontol 2002;73:1153‐1159.
The Effect of Shared Genetic and Environmental Factors on Periodontal Disease Parameters in Untreated Adult Siblings in Guatemala
Authors: Dowsett Sherie A. , Archila Luis , Foroud Tatiana , Koller Daniel , Eckert George J. , Kowolik Michael J. 
Published: February 2005

Background: Increasing evidence supports the role of genetic factors in susceptibility to infectious diseases, including chronic periodontitis. The role of genetic factors in phenotypic expression can be estimated from the degree of resemblance between relatives, as compared with that of unrelated members of a population. Heritability is an estimate of the proportion of total phenotypic variation of a quantitative trait, which is attributable to genetic factors, and is based on the variance within versus between family members. The aim of this study was to determine whether there is a familial basis for periodontal disease status in an untreated population in Guatemala using heritability estimates as a measure of familial clustering of disease.Methods: One‐hundred and thirteen adult subjects (including both siblings and spouse pairs), age range 35 to 60 years, participated in this study. Full‐mouth periodontal examinations were performed and heritability estimates were calculated for mean plaque score, mean gingival index (GI), probing depth (PD), and clinical attachment level (CAL). Intraclass correlation coef‐ficients (ICCs) were calculated using the same parameters for spouses to determine whether a common family environment in adulthood plays a role in disease expression.Results: Only in the case of mean plaque score and mean recession score were heritability estimates significantly above zero at α = 0.05. For spouse pairs, mean GI score, mean PD, and percentage of sites of PD ≥5 mm showed a statistically significant ICC.Conclusions: These results lead us to reject the hypothesis that there is substantial heritability for periodontal disease expression in this population. This may be due to an underlying lack of genetic variation within this sample or may indicate that, compared with the role of environmental factors, the genetic contribution to periodontal disease phenotypes is relatively minor. J Periodontol 2002;73:1160‐1168.
Microbiological Markers for Prediction and Assessment of Treatment Outcome Following Non‐Surgical Periodontal Therapy
Authors: Fujise Osamu , Hamachi Takafumi , Inoue Kenji , Miura Mayumi , Maeda Katsumasa 
Published: February 2005

Background: Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Bacteroides forsythus are considered major putative periodontal pathogens. However, it remains unclear what combinations or what levels of these bacteria influence treatment outcome. The purpose of the present study was to establish useful pathogenic markers for prediction and assessment of treatment outcome following scaling and root planing (SRP).Methods: A total of 1,149 sites in 104 chronic periodontitis patients were clinically examined at baseline. Three months after SRP, 606 sites in 56 of these patients were reexamined. Subgingival plaque samples taken from the examined sites at baseline and 3 months were analyzed for the detection and quantification of A. actinomycetemcomitans, P.gingivalis, and B. forsythus using a colorimetric polymerase chain reaction technique.Results: At baseline, high levels and a combination of P.gingivalis and B. forsythus were frequently detected in diseased sites (74%). SRP reduced the levels and the coexistence of P.gingivalis and B. forsythus (from 75% to 43%). However, in treated sites where there was less reduction of probing depth (<2 mm), or where bleeding on probing (BOP) or suppuration was detected, residual coexistence of P.gingivalis and B. forsythus and a high level of P.gingivalis after SRP were significantly more frequent. Furthermore, SRP did not improve BOP at sites exhibiting initially high levels of A. actinomycetemcomitans.Conclusions: These results suggest that the combination of P.gingivalis and B. forsythus, as well as the level of P.gingivalis, is useful in assessing treatment outcome. Furthermore, the high level of A. actinomycetemcomitans before SRP is a possible valuable predictor of treatment outcome. J Periodontol 2002;73:1253‐1259.
In Vitro Effect of Laser Irradiation on Cementum‐Bound Endotoxin Isolated From Periodontally Diseased Roots
Authors: Liu Cheing‐Meei , Shyu Yow‐Chyun , Pei Shao‐Chi , Lan Wan‐Hong , Hou Lein‐Tuan 
Published: February 2005

Background: In a previous study, we evaluated the in vivo effects of an Nd:YAG laser on periodontal disease by measuring crevicular interleukin (IL)‐1β levels before and after laser application. It was found that laser therapy was less effective than traditional scaling and root planing. These results might be due to incomplete removal of microbial residues and cementumbound endotoxin on root surfaces by the laser. In this study, we explored the in vitro effectiveness of an Nd:YAG laser for the elimination of cementum‐bound endotoxin by measuring IL‐1β changes in stimulated monocytes.Methods: Fresh human monocytes were harvested from adults without periodontitis and grown in RPMI 1640 medium. Diseased cementum particles were collected and prepared from teeth with untreated periodontitis and were irradiated with 5 levels of laser energy. Cementum particles were subjected to endotoxin testing by a limulus amebocyte lysate (LAL) assay and then were incubated with cultured monocytes. Production of IL‐1β in stimulated monocytes was measured by enzyme‐linked immunosorbent assay and quantified by spectrophotometry.Results: The endotoxin unit (EU) of diseased cementum was 18.4 EU/mg, which seemed to be remarkably lower than that of common periodontal pathogens including Porphyromonas gingivalis (381) at 15,300 EU/mg/ml, Prevotella intermedia (ATCC 25611) at 227 EU/mg/ml, and Fusobacterium nucleatum (ATCC 25586) at 1,987 EU/mg/ml. Monocytes subjected to stimulation by diseased cementum particles without laser irradiation produced 124 to 145 pg/ml IL‐1β, 9‐ to 18‐fold higher than that of unstimulated monocytes (7.07 to 15.95 pg/ml). Diseased cementum particles after irradiation with various energy levels of the Nd:YAG laser could still stimulate monocytes to secrete 89 to 129 pg/ml IL‐1β. No statistically significant difference was found in the production of IL‐1β induced by diseased‐bound cementum with or without laser irradiation.Conclusions: The Nd:YAG laser varying from 50 mJ, 10 pps to 150 mJ, 20 pps, for 2 minutes, did not seem to be effective in destroying diseased cementum endotoxin. J Periodontol 2002;73:1260‐1266.
An In Vitro Model of Ciprofloxacin and Minocycline Transport by Oral Epithelial Cells
Authors: Brayton James J. , Yang Qing , Nakkula Robin J. , Walters John D. 
Published: February 2005

Background: Fluoroquinolones and tetracyclines can penetrate epithelial cells, but the mechanism by which they cross the plasma membrane is unclear. In this study, a cell line derived from oral epithelium was used as a model to demonstrate a role for active transport.Methods: Transport of ciprofloxacin and minocycline by confluent cell monolayers was assayed by measuring the increase in cell‐associated fluorescence.Results: Uptake of both agents was saturable and was inhibited at low temperatures. At 37°C, the cells transported ciprofloxacin and minocycline with Km values of 351 and 133 μg/ml, respectively, and maximum velocities of 5.11 and 13.4 ng/min/μg cell protein, respectively. When ciprofloxacin and minocycline were removed from the extracellular medium, the intracellular levels of both agents decreased. Ciprofloxacin efflux from loaded cells occurred more rapidly than with minocycline. Cells accumulated intracellular drug levels that were at least 8‐fold higher than extracellular levels for ciprofloxacin and at least 40‐fold higher for minocycline. Transport of ciprofloxacin and minocycline was significantly influenced by pH and was most favorable at pH 7.7 and 7.2, respectively. While ciprofloxacin transport was Na+ independent, minocycline transport was strongly inhibited when sodium in the medium was replaced with choline. Transport of both agents was inhibited by a variety of organic cations, but the pattern of inhibition was different. Papaverine, phenylephrine, and doxycycline competitively inhibited minocycline transport, but inhibited ciprofloxacin transport by a non‐competitive mechanism.Conclusions: Epithelial cells take up ciprofloxacin and minocycline via different active transport systems. These transporters may play an important role in enhancing the effectiveness of these agents against invasive pathogens. J Periodontol 2002;73:1267‐1272.
The Pattern of Alveolar Crest Height Change in Healthy Postmenopausal Women After 3 Years of Hormone/Estrogen Replacement Therapy
Authors: Hildebolt Charles F. , Pilgram Thomas K. , Yokoyama‐Crothers Naoko , Vannier Michael W. , Dotson Mary , Muckerman Jane , Armamento‐Villareal Reina , Hauser Jay , Cohen Sheldon , Kardaris E. Eugenia , Hanes Philip , Shrout Michael K. , Civitelli Roberto 
Published: February 2005

Background: The loss of ovarian function at menopause is associated with loss of postcranial and oral bone. Hormone/estrogen replacement therapy (HRT/ERT) has a positive effect on both postcranial and oral bone. The objective of the study was to determine if the positive effect of HRT/ERT on alveolar crest height (ACH) is generalized or site specific.Methods: The sample consisted of 49 women who completed a 3‐year, HRT/ERT prospective study. Cemento‐enamel junction distances (ACH) were measured on digitized images of bitewing radiographs. Lumbar spine and proximal femur bone mineral densities (BMDs) were determined with dual‐energy x‐ray absorptiometric scans. Measurements were made at baseline and at the end of year 3. For the 3‐year study period, mean change in ACH was determined for each patient. In addition, the sites with the greatest, second and third greatest ACH changes were determined for each patient. Correlations between changes in ACH (as determined by the various methods) and postcranial BMD were determined.Results: Mean ACH changes had an average correlation (r) of −0.24 with femoral and lumbar spine BMDs. Although the largest site‐specific change in ACH resulted in a mean correlation of −0.21, the correlations for the second and third largest changes in ACH dropped to −0.15 and −0.12. Overall, the correlations for site‐specific changes were substantively smaller than those for generalized change.Conclusions: The data of this study indicate that ACH change attributable to HRT/ERT is generalized rather than site specific. Studies of the effect of HRT/ERT on ACH should employ multiple measurements to minimize measurement errors associated with site‐specific measurements. J Periodontol 2002;73:1279‐1284.
Bactericidal Effect of the Er:YAG Laser on Dental Implant Surfaces: An In Vitro Study
Authors: Kreisler Matthias , Kohnen Wolfgang , Marinello Claudio , Götz Hermann , Duschner Heinz , Jansen Bernd , D'Hoedt Bernd 
Published: February 2005

Background: The aim of the in vitro study was to examine the bactericidal effect of an Er:YAG laser on common dental implant surfaces.Methods: Seventy‐two titanium platelets with 3 different surfaces—sandblasted and acid‐etched (SA), titanium plasmasprayed (TPS), and hydroxyapatite‐coated (HA)—were incubated with a suspension of Streptococcus sanguinis (ATCC 10556). Irradiation at pulse energies of 60 and 120 mJ and a frequency of 10 pps was performed on a computer‐controlled XY translation stage. After laser treatment the specimens were sonicated and the bacterial growth examined by counting colony forming units on blood agar plates. Temperature elevations during irradiation were investigated using K‐type thermocouples. Laser treated implant surfaces were analyzed by means of electron microscopy.Results: Compared to non‐irradiated specimens, mean bacterial reductions of 99.51% (SA), 98.39% (HA), and 99.6% (TPS) at a pulse energy of 60 mJ and 99.92% (SA), 99.85% (HA), and 99.94% (TPS) at 120 mJ were calculated. At these laser parameters, no excessive temperature elevations or morphological implant surface alterations were detected.Conclusions: Even at low energy densities, the Er:YAG laser has a high bactericidal potential on common implant surfaces. Clinical studies are justified to evaluate the applicability and efficacy of the Er:YAG laser in the treatment of peri‐implantitis. J Periodontol 2002;73:1292‐1298.
The Relationship of Oral Malodor in Patients With or Without Periodontal Disease
Authors: Figueiredo Luciene Cristina , Rosetti Elizabeth Pimentel , Marcantonio Elcio , Marcantonio Rosemary Adriana C. , Salvador Sergio Luiz 
Published: February 2005

Background: Halitosis has been correlated with the concentration of volatile sulfur compounds (VSC) produced in the oral cavity by metabolic activity of bacteria colonizing the periodontal area and the dorsum of the tongue. The aim of this study was to determine whether there is some relationship between the presence of N‐benzoyl‐DL‐arginine‐2‐napthylamide (BANA)‐positive species Treponema denticola, Porphyromonas gingivalis, and Bacteroides forsythus and clinical and oral malodor parameters.Methods: Twenty‐one subjects (21 to 59 years old) with probing depths (PD) >3.0 mm and 20 subjects (21 to 63 years old) with PD ≤3.0 mm (controls) participated. The quality of the mouth air was assessed organoleptically, and a portable sulfide monitor was used to measure the concentration of VSC. Clinical parameters, plaque index (PI) and gingival index (GI), were obtained from 6 teeth. Samples for BANA test were taken from the dorsal surface of the tongue, saliva, and the 6 reference teeth.Results: The scores of PI, GI, subgingival samples that tested positive for BANA hydrolyzing species, organoleptic ratings, and VSC values were significantly higher in the subjects with PD >3.0 mm (P <0.01, Mann‐Whitney U test). There was a correlation between BANA hydrolysis by subgingival plaque bacteria and VSC values (r = 0.55, P <0.01), and between GI and VSC values (r = 0.48, P <0.05) in patients with PD >3.0 mm. There was no significant correlation between these parameters in the control group.Conclusion: These results confirm that the BANA hydrolyzing bacteria in the subgingival plaque are an important source of malodor production in the oral cavity. J Periodontol 2002;73:1338‐1342.
Predicting Tooth Loss During a Population‐Based Study: Role of Attachment Level in the Presence of Other Dental Conditions
Authors: Gilbert Gregg H. , Shelton Brent J. , Chavers L. Scott , Bradford Edward H. 
Published: February 2005

Background: Our objectives were to quantify: 1) the association between incident tooth loss and prior periodontal attachment level; and 2) the contribution to tooth loss made by nonperiodontal conditions in increasingly periodontally involved teeth.Methods: The Florida Dental Care Study was a prospective cohort study of persons who at baseline had at least 1 tooth and were 45 years or older. In‐person interviews and clinical examinations were conducted at baseline, and at 24 and 48 months, with telephone interviews at 6‐month intervals in between. A regression model was used to simultaneously quantify toothspecific predictors of tooth loss, with person‐level factors taken into account.Results: Of the 687 persons who participated for a 48‐month clinical examination, 36% lost 1 or more teeth during follow‐up, and 5.0% of all teeth were lost. Attachment level up to 2 years before tooth loss was strongly predictive of incident tooth loss, with increases in risk for each millimeter in attachment loss. Certain other tooth‐specific conditions (tooth mobility, bulk restoration fracture, decayed surfaces, filled surfaces, tooth type and arch location, root fragment) were strongly and independently associated with increased risk for tooth loss, while others were not (prosthetic crown coverage, cusp fracture, root surface defect). Propensity to choose extraction over other treatment alternatives, as reported by participants at baseline, was also strongly predictive of tooth loss.Conclusions: Increasingly severe attachment level was consistently associated with an increased risk for tooth loss in this sociodemographically diverse sample, with or without other tooth‐specific conditions taken into account. J Periodontol 2002; 73:1427‐1436.
Osseous Reconstruction Using a Membrane Barrier Following Marginal Mandibulectomy: An Animal Pilot Study
Authors: Peled M. , Machtei E.E. , Rachmiel A. 
Published: February 2005

Background: Invasive and malignant tumors of the oral soft tissues adjacent to the mandible are often treated with partial resection of the osseous structure adjacent to the lesion (marginal mandibulectomy). Autogenous bone graft and composite bone grafts are being used to fill the osseous defects with various degrees of success. The aim of the present study was to explore the utilization of membrane barriers and the principle of guided bone regeneration to negotiate these defects.Methods: Following the removal of P1, P2, and P3, experimental bilateral marginal mandibulectomy defects were created in 4 adult dogs. The bone segments (measuring 25 mm × 15 mm) were then removed. Each side was then randomly selected for either experimental (titanium‐reinforced expanded polytetrafluoroethylene membrane, [ePTFE‐TR]) or control (repositioning flaps) treatment. Postoperatively, the animals were put on soft diet, antibiotics, and analgesics. Sutures were removed under light sedation after 4 weeks, and the area was left to heal and mature for 4 to 6 months (mean 5.3 months). The animals were then sacrificed, and block sections of the mandible were obtained for macroscopic and histological evaluation.Results: The size of the residual defect (the vertical distance between the most apical depression in the ridge and the horizontal line connecting the free gingival margins of the proximal teeth) in the experimental sites (6.10 ± 1.00 mm) was much smaller compared to the controls (10.65 ± 0.82 mm), which was statistically significant (P = 0.0127). Histomorphometric measurements of new bone formation (NBF) revealed a similar pattern: for the experimental sites, NBF was 8.08 ± 0.85 mm compared to 4.99 ± 0.61 mm in the controls. These differences were also statistically significant (P = 0.0257).Conclusions: A regenerative approach to large mandibular osseous defects has been described. If this new treatment modality is further substantiated in other independent studies, it might prove a useful tool in restoring the lost osseous structure associated with marginal mandibulectomy procedures. J Periodontol 2002;73:1451‐1456.