bluuebunny/crossref_metadata_2025_split huggingface dataset:
Porous Bovine Bone Mineral in Healing of Human Extraction Sockets. Part 1: Histomorphometric Evaluations at 9 Months
Authors: Artzi Zvi , Tal Haim , Dayan Dan 
Published: February 2005

Background: Extraction socket wound healing is characterized by resorption of the alveolar bone at the extraction site. This produces a decrease in ridge volume, deformations of ridge contours, and, thus, difficulties in delayed placement of root‐form implants in an ideal position. Cancellous porous bovine bone mineral (PBBM) applied to fresh extraction sockets has recently been proposed to minimize the reduction in ridge volume. The aim of this study was to investigate the influence of PBBM grafted particles on the histopathologic pattern of the intrasocket regenerated bone and to evaluate histomorphometrically the healed PBBM grafted extraction socket site at 9 months' post‐extraction.Methods: PBBM particles (250 to 1,000 µ in size) were grafted in 15 fresh human extraction sockets in 15 patients. Socket wall bone height was measured from the crestal ridge level before the mineral particles were inserted. Primary soft tissue closure was performed to protect the grafted particles via a pediculated split palatal flap. At 9 months, socket bone walls were remeasured and cylinder bone samples of the previously PBBM‐grafted sites were obtained. Decalcified specimens were sectioned at a cross‐horizontal plane and stained with hematoxylin and eosin for histopathologic and histomorphologic examination. Tissue area percentage of bone, PBBM, and connective tissue (CT) was calculated for each specimen from the crestal to the apical region and changes in values compared.Results: Average clinical overall bone fill of the augmented socket sites was 82.3%. Histologically, PBBM particles were observed in all specimens. Newly formed bone was characterized by abundance of cellular woven‐type bone in the coronal area, while lamellar arrangements could be identified only in the more apical region. New osseous tissue adhered to the PBBM. Histomorphometric measurements showed an increase of mean bone tissue area along the histological sections from 15.9% in the coronal part to 63.9% apically (average 46.3%). CT fraction decreased from 52.4% to 9.5% (average 22.9%) from the crestal to the apical region. PBBM area fraction varied from 26.4% to 35.1% (average 30.8%). Statistical analysis of the comparison between areas of bone, CT, and PBBM was performed in different points along the coronal‐apical axis. Differences were significant (P <0.01) at the most crestal, middle, and apical section cut areas, but not at the cervical section cuts. Bone area fraction increased in the apical direction as much as CT correlatively decreased. Unlike CT and bone, PBBM retained constant relative volume (approximately 30%), regardless of the depth of the specimen cores.Conclusions: PBBM particles are an appropriate biocompatible bone derivative in fresh extraction sockets for ridge preservation. The resorbability of this xenograft could not be recognized in a 9‐month period. Further investigation is needed to clarify the resorptive mechanisms of PBBM. J Periodontol 2000;71:1015‐1023.
“Checkerboard” Assessments of Periodontal Microbiota and Serum Antibody Responses: A Case‐Control Study
Authors: Papapanou Panos N. , Neiderud Anne‐Marie , Papadimitriou Alexandra , Sandros Jens , Dahlén Gunnar 
Published: February 2005

Background: We explored the association between subgingival microbial profiles and serum IgG responses to periodontal microbiota in relation to clinical periodontal status.Methods: One hundred thirty‐one (131) periodontitis patients aged 29 to 74 years (mean 51.8) were ageand gender‐matched with 74 periodontally intact controls (range 26 to 77, mean 49.3). Smoking habits and health history were recorded and assessments of plaque, bleeding on probing, probing depth, and attachment level were performed at 6 sites per tooth on all present teeth, excluding third molars. Subgingival plaque samples were obtained from each tooth in one upper and one lower quadrant (maximum 14 samples/subject; 2,440 samples total) and analyzed with respect to 19 species by means of whole genomic DNA probes. Serum IgG antibodies against the same 19 species were assessed by an immunoassay.Results: Cases displayed an average of 22.7 teeth, 20.3 sites with probing depth ≥6 mm, and 18.9 sites with attachment loss ≥6 mm. Corresponding figures for controls were 27.1, 0.1, and 1.0, respectively. Heavy smoking was 3 times more frequent among cases than controls (32.1% versus 9.6%). Higher levels of Porphyromonas gingivalis, Porphyromonas endodontalis, Prevotella intermedia, Prevotella nigrescens, Prevotella melaninogenica, Bacteroides forsythus, Fusobacterium nucleatum, Treponema denticola, Eubacterium nodatum, Peptostreptococcus micros, and Campylobacter rectus were found in cases and higher levels of Eikenella corrodens, Veillonella parvula, and Actinomyces naeslundii in controls. Cases displayed higher IgG levels against P. gingivalis and Actinobacillus actinomycetemcomitans, while controls displayed higher levels against F. nucleatum, T. denticola, E. nodatum, and Capnocytophaga ochracea. Positive correlations between bacterial colonization and antibody responses were identified for 9 species in controls. In cases, however, statistically significant correlations were observed for only 3 species out of which only one was positive (V. parvula). Both bacterial levels and antibody responses declined in ages over 55 years. A logistic regression employing selected elements of bacterial colonization and antibody responses as independent variables resulted in 81.1% correct diagnosis, with sensitivity of 83.1%, specificity of 77.8%, positive predictability of 86%, and negative predictability of 73.7%. Smoking did not reach statistical significance in this model.Conclusion: A combined microbial colonization/antibody response profile can effectively discriminate between periodontitis patients and periodontally intact controls. J Periodontol 2000;71:885‐897.
Evidence for the Role of Highly Leukotoxic Actinobacillus actinomycetemcomitans in the Pathogenesis of Localized Juvenile and Other Forms of Early‐Onset Periodontitis
Authors: Haraszthy Violet I. , Hariharan Govind , Tinoco Eduardo M.B. , Cortelli Jose R. , Lally Edward T. , Davis Elaine , Zambon Joseph J. 
Published: February 2005

Background: Actinobacillus actinomycetemcomitans leukotoxin is thought to be an important virulence factor in the pathogenesis of localized juvenile and other forms of early‐onset periodontitis. Some highly leukotoxic A. actinomycetemcomitans strains produce 10 to 20 times more leukotoxin than other minimally leukotoxic strains. The distribution, clonality, and intrafamilial transmission of highly leukotoxic A. actinomycetemcomitans were examined in order to determine the importance of leukotoxin in the pathogenesis of periodontitis.Methods: The polymerase chain reaction (PCR) was used to differentiate highly leukotoxic from minimally leukotoxic strains in examining 1,023 fresh A. actinomycetemcomitans isolates and strains from our culture collection. These were obtained from 146 subjects including 71 with localized juvenile periodontitis (LJP), 4 with early‐onset periodontitis, 11 with post‐localized juvenile periodontitis, 41 with adult periodontitis, and 19 periodontally normal subjects. The arbitrarily primed polymerase chain reaction (AP‐PCR) analysis of 30 oral isolates from each of 25 subjects was used to determine the intraoral distribution of A. actinomycetemcomitans clones. AP‐PCR was also used to examine the transmission of A. actinomycetemcomitans in 30 members of 6 families. The clonality of 41 highly leukotoxic A. actinomycetemcomitans strains was evaluated by both AP‐PCR and ribotyping.Results: Highly leukotoxic A. actinomycetemcomitans was found only in subjects with localized juvenile and early‐onset periodontitis. Fifty‐five percent of the LJP subjects harbored highly leukotoxic A. actinomycetemcomitans isolates. Seventy‐three percent of the A. actinomycetemcomitans isolates in these subjects were highly leukotoxic. Highly leukotoxic A. actinomycetemcomitans infected younger subjects (mean age 13.95 years, range 5 to 28 years) than minimally leukotoxic (mean age 35.47 years, range 6 to 65 years). Most subjects were infected with only one A. actinomycetemcomitans genotype. However, PCR of whole dental plaques and subsequent analysis of up to 130 individual oral isolates suggested a possible shift in A. actinomycetemcomitans over time in that a few subjects harbored both highly leukotoxic and minimally leukotoxic strains. AP‐PCR analysis was consistent with intrafamilial A. actinomycetemcomitans transmission. Ribotyping and AP‐PCR analysis confirmed a previous report that highly leukotoxic A. actinomycetemcomitans consists of a single clonal type.Conclusions: This study suggests that localized juvenile and other forms of Actinobacillus‐associated periodontitis are primarily associated with the highly leukotoxic clone of A. actinomycetemcomitans. J Periodontol 2000;71:912‐922.
Prospective Study on the Augmentation of the Maxillary Sinus With Calcium Sulfate: Histological Results
Authors: De Leonardis Dario , Pecora Gabriele E. 
Published: February 2005

Background: The main goal of the sinus elevation procedure is the formation of vital bone to allow the tissue integration of endosseous implants to support prosthetic restorations in the edentulous posterior maxilla. The ideal graft material is yet to be found. The present study investigated the histologic results of a sinus augmentation procedure performed with calcium sulfate as the grafting material.Methods: The clinical trial consisted of 2 groups: a first (control) group of 12 patients (15 sinuses) in which the material was carefully placed but not stratified. In the second (test) group, 45 patients (50 sinuses) were treated by modifying the application. The calcium sulfate was putty‐like in consistency and placed as it hardened in layers, avoiding fluid contamination. The histologic samples were collected, either at 9 months, at the uncovering procedure (for implants placed simultaneously with grafting material), or at 6 months at the time of implant insertion (for implants placed at a later stage).Results: The augmentation procedure resulted in good, new tissue formation within the sinuses when clinically and radiographically evaluated. The technique used in the test group produced a reduction in the graft shrinkage during healing, therefore slowing down the material resorption rate. Histologically, new bone formation with progressive lamellar maturation was found in both groups. Some particles produced by calcium sulfate resorption were still present after 6 months in the test group specimens, but no longer detectable after 9 months. Samples from the control group showed a mean histomorphometric bone density of 34.25% ± 10.02, while samples from the test group showed a mean value of 55.54% ± 19.82.Conclusions: The results of this study indicate that calcium sulfate appears to be an effective material for sinus augmentation, yielding vital bone suitable for implant integration. In addition, the technique used in the test group seemed to improve the quality and quantity of bone formation. J Periodontol 2000;71:940‐947.
Occurrence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia in Progressive Adult Periodontitis
Authors: López Néstor J. 
Published: February 2005

Background: Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, and Prevotella intermedia are the major periodontal bacteria species in most forms of progressive periodontitis in Scandinavia and the United States. The occurrence of periodontal pathogens appears to be different in subjects of different ethnic origin, and geographical factors may influence the distribution of these species.Methods: The occurrence of A. actinomycetemcomitans, P. gingivalis, and P. intermedia was determined using a DNA probe in progressive adult periodontitis in Chileans. Sixty patients (mean age 43.6 ± 8 years) who had not previously received any type of periodontal therapy were selected. Bleeding on probing, probing depth, and clinical attachment level measurements were made with an automated probe. Patients were monitored at 2‐month intervals until at least 2 sites exhibited ≥2 mm attachment loss. Two subgingival plaque samples from active sites were taken in 56 subjects and matched with 2 plaque samples from inactive sites in the same individuals.Results: P. gingivalis was found in 75% of active sites and in 59.7% of inactive sites in 96% of the patients (P = 0.022). P. gingivalis at high levels of detection was significantly more frequent in active sites (48.2%) than in inactive sites (31.2%) (P = 0.014). A. actinomycetemcomitans was detected in 6.25% of active sites and in 12.5% of inactive sites in 11.6% of patients. P. intermedia was found in 33% of patients and at a significantly higher proportion in active sites (49.1%) than in inactive sites (30.3%) (P = 0.006). There was a significantly higher proportion of inactive sites (34.8%) than active sites (19.6%) without any of the 3 pathogens (P = 0.016). Bleeding on probing was significantly more associated with active sites with high levels of P. gingivalis and with active sites with P. intermedia than with inactive sites.Conclusions: A high prevalence of P. gingivalis and P. intermedia was found in adult periodontitis, and the occurrence of these bacteria appears to be higher in Chileans than in other populations. No apparent association exists between A. actinomycetemcomitans and progressive adult periodontitis in Chileans. J Periodontol 2000;71:948‐954.
Phenytoin and Cyclosporin A Suppress the Expression of MMP‐1, TIMP‐1, and Cathepsin L, But Not Cathepsin B in Cultured Gingival Fibroblasts
Authors: Yamada Hisa , Nishimura Fusanori , Naruishi Koji , Chou Hsin‐Hua , Takashiba Shogo , Albright George M. , Nares Salvador , Iacopino Anthony M. , Murayama Yoji 
Published: February 2005

Background: Fibroblasts are known not only to synthesize and secrete extracellular matrix proteins, but also to degrade them for connective tissue remodeling. Drug‐induced gingival overgrowth is characterized by a massive accumulation of extracellular matrix components in gingival connective tissues. Although some previous reports suggested that causative drugs stimulated the fibroblast proliferation, the results are not conclusive yet. In this study, we hypothesized that drug‐induced gingival overgrowth could be a consequence of impaired ability of matrix degradation rather than an enhanced proliferation of gingival fibroblasts induced by these drugs.Methods: Normal human gingival fibroblasts were cultured with or without either 20 µg/ml of phenytoin or 200 ng/ml of cyclosporin A. Total RNA and cellular proteins were collected every day for RTPCR analyses and for measuring lysosomal enzyme activity. In addition, an immunohistochemical study was performed to detect lysosomal enzymes in cells from enlarged gingiva of the patients with phenytoin‐induced gingival overgrowth.Results: RT‐PCR analyses revealed that these drugs suppressed the expression of MMP‐1, TIMP‐1, and cathepsin L, but not that of cathepsin B in a time‐dependent manner. Then, we measured the activity of lysosomal enzymes and cathepsin B and L. The results indicated that although cathepsin B activity was not observed to be impaired, regardless of the drugs used in these cells, both total and active forms of combined activity of cathepsins B and L were suppressed in a time‐dependent manner.Conclusions: The results indicate that, besides suggested effects of these drugs on gingival fibroblasts and/or on accumulated cells in the gingival tissues, extracellular matrix‐degrading ability, particularly that by cathepsin L, is also suppressed by cyclosporin A and phenytoin in gingival fibroblasts, and that lysosomal enzyme plays an important role in the pathogenesis of drug‐induced gingival hyperplasia. J Periodontol 2000;71:955‐960.
Ultrastructural and Immunoelectron Microscopic Studies of the Peri‐Implant Epithelium‐Implant (Ti‐6Al‐4V) Interface of Rat Maxilla
Authors: Ikeda Hidehiro , Yamaza Takayoshi , Yoshinari Masao , Ohsaki Yasuyoshi , Ayukawa Yasunori , Kido Mizuho A. , Inoue Takashi , Shimono Masaki , Koyano Kiyoshi , Tanaka Teruo 
Published: February 2005

Background: The role played by the internal basal lamina (IBL) and hemidesmosomes between an implant and the periimplant epithelium (PIE) in the adherence of the epithelium to the implant is controversial. This study used rat maxilla implantation models to clarify the ultrastructure of the PIE‐implant interface.Methods: Ti‐6Al‐4V implants were inserted either immediately or 2 weeks after the extraction of the upper left first molar of 6‐ or 4‐week‐old rats, respectively. The junctional epithelium (JE) of the upper right molars in the same animals was used as a control. Four weeks after implantation, the animals were sacrificed to prepare specimens for light and immunoelectron microscopy.Results: Under light microscopy, the PIE appeared to attach to the implant surface. Ultrastructurally, IBL, consisting of the lamina densa and lamina lucida, and hemidesmosomes were formed only in the lower region, and rarely in the middle region, of the PIE‐implant interface. In control teeth, the IBL and hemidesmosomes formed throughout the dento‐JE interface. Laminin‐1 was found in the IBL and also in the vesicles and vacuoles of the PIE and JE cells. Statistical analysis showed that there was also a significant difference in the amount of IBL between the PIE‐implant and dento‐JE interfaces.Conclusions: PIE attached to the implant via hemidesmosomes and IBL in the lower region of the PIE‐implant interface. Although PIE cells may secrete laminin‐1, which contributes to epidermal cell adhesion, the PIE which attaches to implants only in the lower region of the interface is considered to be the poorly adhered epithelium. J Periodontol 2000;71:961‐973.
Inverse Dose‐ and Time‐Dependent Effect of Basic Fibroblast Growth Factor on the Gene Expression of Collagen Type I and Matrix Metalloproteinase‐1 by Periodontal Ligament Cells in Culture
Authors: Palmon A. , Roos H. , Edel J. , Zax B. , Savion N. , Grosskop A. , Pitaru S. 
Published: February 2005

Background: Growth factors are known to play a major role in the regeneration of the periodontium. Basic fibroblast growth factor (bFGF) is a polypeptide growth factor considered to have a role in chemotaxis and mitogenesis of periodontal ligament cells (PLC). The aim of this study was to assess the dose‐dependent effect of bFGF administration on the levels of gene expression of collagen type I (a1) (col I), collagen type III (col III), and collagenase‐1 (MMP‐1) in PLC.Methods: PLC were cultured in different concentrations of bFGF (0.1 to 10 ng of bFGF) for 14 and 21 days. At each time point, the gene expression of the examined molecules was assessed semi‐quantitatively by reverse transcription‐polymerase chain reaction (RT‐PCR) assay.Results: The results indicated that bFGF exhibits an inverse time‐ and dose‐dependent effect on the gene expression of col I and MMP‐1: it simultaneously downregulates the gene expression of col I and upregulates the gene expression of MMP‐1. On the other hand, bFGF had no dose‐dependent effect on col III gene expression. The effect of bFGF on the expression of the three genes was modulated by the time of incubation with bFGF.Conclusions: These results suggest that bFGF is one of the important regulators involved in the active remodeling of col I in the periodontal ligament and possibly in other connective tissues. J Periodontol 2000;71:974‐980.
Human Herpesviruses and Porphyromonas gingivalis Are Associated With Juvenile Periodontitis
Authors: Michalowicz Bryan S. , Ronderos Mauricio , Camara‐Silva Reneé , Contreras Aldofo , Slots J⊘rgen 
Published: February 2005

Background: Although herpesviruses have been associated with adult periodontitis, their relationship with juvenile periodontitis (JP) has not been established. This case‐control study examined possible associations between JP and pathogenic bacteria, the human cytomegalovirus (HCMV), and the Epstein‐Barr type 1 virus (EBV‐1).Methods: Subjects were participants in a larger survey of schoolchildren in North‐Central Jamaica. Subgingival plaque samples from 15 subjects with JP, 20 with incipient periodontitis (IP), and 65 randomly‐selected healthy controls were assayed for Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans using a 16S rRNA polymerase chain reaction (PCR) identification method, and for HCMV and EBV‐1 using nested PCR identification.Results: Strong bivariate associations were found between JP and P. gingivalis (odds ratio [OR] = 12.7; 95% CI = 2.6, 61.4), HCMV (OR = 10.0; 95% CI = 2.7, 36.3), and A. actinomycetemcomitans (OR = 8.0; 95% CI = 2.3, 27.5), but not EBV‐1. In multivariate analyses, P. gingivalis remained a significant explanatory variable (OR = 7.8; 95% CI = 1.5, 40.9); however, the associations were marginal for HCMV (OR = 4.6; 95% CI = 0.9, 22.7), and non‐significant for A. actinomycetemcomitans (OR = 2.0; 95% CI = 0.4, 9.7). The associations with JP and the extent of attachment loss were even stronger when both P. gingivalis and HCMV were detected together. P. gingivalis (OR = 3.9; 95% CI = 1.3, 12.0) and EBV‐1 (OR = 3.3; 95% CI = 1.0, 10.3) were the only significant explanatory variables in the multivariate analysis of IP.Conclusions: P. gingivalis is the strongest and most stable indicator of periodontitis in Jamaican adolescents. Co‐infection with P. gingivalis and HCMV appears to be particularly deleterious to periodontal health. J Periodontol 2000;71:981‐988.