bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bacterial Diversity in Necrotizing Ulcerative Periodontitis in HIV‐Positive Subjects
Authors: Paster Bruce J. , Russell Meaghan K. , Alpagot Tamer , Lee Alice M. , Boches Susan K. , Galvin Jamie L. , Dewhirst Floyd E. 
Published: February 2005

Background: Necrotizing ulcerative periodontitis (NUP) is a painful and potentially debilitating affliction that affects about 2% to 6% of HIV‐positive subjects. NUP may be caused by specific microorganisms that are presently unknown or by microbial species not usually thought to cause periodontal infections. The purpose of this study was to define the bacterial species associated with NUP in HIV‐positive patients.Methods: 16S rRNA bacterial genes of DNA isolated from subgingival plaque of 8 HIV‐positive subjects with NUP were amplified by polymerase chain reaction (PCR) and cloned into Escherichia coli. The sequences of cloned inserts were used to determine species identity or closest relatives by comparison with known sequences. The microbial profiles in subgingival plaque of subjects with NUP, chronic periodontitis, and periodontal health were compared using a battery of over 200 oligonucleotide probes in a PCR‐based, reverse‐capture, checkerboard DNA‐DNA hybridization assay.Results: Sequence analysis of over 400 clones revealed 108 species; 65 were “uncultivable” phylotypes, of which 26 were novel to NUP subjects. Species or phylotypes most commonly detected were Bulleidia extructa, Dialister, Fusobacterium, Selenomonas, Peptostreptococcus, Veillonella, and the phylum TM7. Based on sequence analysis and checkerboard analysis, NUP did not possess the classical periodontal pathogens such as Porphyromonas gingivalis.Otherwise, the microbial profiles of NUP and periodontitis had many similarities. The microbial profiles of subgingival plaque from periodontally healthy subjects were different and less complex in comparison to the profiles of both disease groups.Conclusions: Certain species appear to be associated with health and periodontal diseases. The putative pathogens associated with periodontal disease in HIV‐negative subjects are not associated with NUP in HIV‐positive subjects. Ann Periodontol 2002;7:8‐16.
Cellular Responses to Oral Pathogens
Authors: Kuramitsu Howard K. , Miyakawa H. , Qi M. , Kang I.C. 
Published: February 2005

Background: Several previous epidemiological studies, along with the results of more recent animal model approaches, have suggested a role for periodontitis in atherosclerosis. Such an association could be mediated by direct interactions of periodontopathic bacteria with host vascular tissues.Methods:The interactions of Porphyromonas gingivalis with endothelial cells and macrophages in vitro were investigated relative to modification of low‐density lipoproteins (LDL).Results: P. gingivalis 381, its outer membrane vesicles, and the lipopolysaccharide (LPS) derived from these organisms were all shown to induce modification of LDL in the presence of the murine macrophage J774.A.1. Such alterations led to an increase in the migration of the particles through agarose gels. In addition,u direct modification of LDL by strain 381 was demonstrated in the absence of macrophages. This latter property appears to be related to the potent protease activities of the bacterium. These properties may contribute to modification of LDL to forms which have been strongly implicated in cholesterol lipid accumulation in vascular tissues. P. gingivalis 381 also appears to induce cyclooxygenase‐2 expression in endothelial cells as determined with human umbilical vascular endothelial cells (HUVEC).Conclusions: These in vitro results with vascular cells in culture suggest a molecular basis for a potential role for periodontopathic bacteria such as P. gingivalis in augmenting foam cell formation characteristic of atherosclerotic lesions. Ann Periodontol 2002;7:90‐94.
Guided Tissue Regeneration for the Treatment of Periodontal Intrabony and Furcation Defects. A Systematic Review
Authors: Murphy Kevin G. , Gunsolley John C. 
Published: February 2005

Background: Many clinical studies have demonstrated that guided tissue regeneration (GTR) is a successful treatment modality of periodontal reconstructive surgery and it has become an accepted procedure in most periodontal practices.Rationale: The purpose of this structured review was to assess the efficacy of guided tissue regeneration (GTR) procedures in patients with periodontal osseous defects compared with surgical controls on clinical, radiographic, adverse, and patient‐centered outcomes. It extends the scope of previous GTR systematic reviews, which were limited to randomized controlled studies, by the scope of outcome measures examined, and the duration of the study.Focused Question: In patients with periodontal osseous defects, what is the effect of physical barriers compared with surgical controls on clinical, radiographic, adverse, and patient‐centered outcomes?Search Protocol: An electronic search of the Cochrane Oral Health Group Trials Register and MEDLINE databases was performed. Manual searching of journals included Journal of Clinical Periodontology, Journal of Periodontology, and Journal of Periodontal Research up to January 2002. This manual search also included review of relevant bibliographies. Two manufacturers of GTR devices were contacted regarding unpublished data.Selection CriteriaInclusion criteria: Studies were selected for review if the evidence level was 3B (cohort) or above, at least 6 months duration, and compared a test GTR intervention with a surgical control.Exclusion criteria: Studies with experimental design problems; histologic or microbiological investigations; or those with outcome measurements, study populations, or study duration not consistent with the inclusion criteria were excluded. Primary outcome measures for intrabony defects were: clinical attachment level (CAL) gain, probing depth reduction (PD), gingival recession (REC) reduction; for furcation defects: vertical probing attachment level (VPAL) gain, vertical probing depth reduction (VPD), horizontal probing depth reduction (HPD), horizontal open probing attachment level gain (HOPA), and vertical open probing attachment level gain (VOPA). Meta‐analysis was performed to compare GTR procedures to other surgical treatments and to examine the resulting clinical outcomes.

Main Results

For the primary outcome variables, in both intrabony‐defect and furcation‐defect studies, GTR was favored over open flap debridement (OFD) therapies (P 0.0001).

No differences were detected among barrier types, but barrier types could explain some heterogeneity in the results

Augmentation of the GTR barrier with a particulate graft enhanced VPD (P <0.05), VPAL, and HOPA, but none of the intrabony outcomes.

Reviewer's Conclusions: Overall, GTR is consistently more effective than OFD in the gain of clinical attachment and probing depth reduction in the treatment of intrabony and furcation defects.Ann Periodontol 2003;8:266‐302.
A Six‐Month Comparison of Three Periodontal Local Antimicrobial Therapies in Persistent Periodontal Pockets
Authors: Kinane D.F. , Radvar M. 
Published: February 2005

Background: Currently, several local antimicrobial delivery systems are available to periodontists. The aim of this 6‐month follow‐up parallel study was to evaluate the efficacy of three commercially available local delivery systems as adjuncts to scaling and root planing in the treatment of sites with persistent periodontal lesions.Methods: Seventy‐nine patients with 4 pockets ≥ 5 mm and bleeding on probing and/or suppuration were randomized into 4 treatment groups which included: scaling and root planing alone (S) (20 patients), or in conjunction with the application of 25% tetracycline fibers (S+Tet) (19 patients), or 2% minocycline gel (S+Min) (21 patients), or 25% metronidazole gel (S+Met) (19 patients). Clinical measurements were taken at baseline, 6 weeks, 3 months, and 6 months after antimicrobial application. Treatments were applied using the distributors' recommended protocols.Results: All 4 therapies resulted in significant improvements from baseline in probing depth, attachment level, bleeding on probing, and the Modified Gingival Index (MGI) scores. The improvements in clinical parameters were greater in all 3 adjunctive treatment groups than scaling and root planing alone. The mean probing depth reductions at 6 months were: scaling + tetracycline = 1.38 mm; scaling + metronidazole = 0.93 mm; scaling + minocycline = 1.10 mm; and scaling alone = 0.71 mm. The probing depth reduction at all time points was significantly greater in the scaling plus tetracycline fiber group than the scaling and root planing alone group (P<0.01). There was also a significant improvement for scaling plus tetracycline fiber application over scaling and metronidazole at both 6 weeks and 3 months, although this did not remain significant at the 6‐month visit. While the frequency of sites with suppuration was markedly reduced following all antimicrobial treatments, the most effective reductions were seen in the scaling plus tetracycline fiber group, followed by the minocycline group.Conclusions: Although all 3 locally applied antimicrobial systems seem to offer some benefit over scaling and root planing alone, a treatment regimen of scaling and root planing plus tetracycline fiber placement gave the greatest reduction in probing depth over the 6 months after treatment. J Periodontol 1999; 70: 1‐7.
Prognosis Versus Actual Outcome. IV. The Effectiveness of Clinical Parameters and IL‐1 Genotype in Accurately Predicting Prognoses and Tooth Survival
Authors: McGuire Michael K. , Nunn Martha E. 
Published: February 2005

Background: Recently, a genetic marker (IL‐1 genotype) that identifies individuals at higher risk for developing severe periodontal disease was discovered. A subgroup of the population reported on earlier was evaluated to determine if knowledge of the patient's IL‐1 genotype would improve accuracy in assignment of prognoses and prediction of tooth loss.Methods: This subgroup consisted of 42 patients (1,044 teeth) in maintenance care for 14 years; 16 tested IL‐1 genotype‐positive (IL‐1GP). Nine were smokers, and 30 had a history of smoking, with an average of 29.44 pack years. A multiple Cox regression model and Kaplan‐Meier survival plots were fit to the subset of patients to evaluate tooth loss.Results: Both IL‐1GP and heavy smoking were significantly related to tooth loss. A positive IL‐1 genotype increased the risk of tooth loss by 2.7 times, and heavy smoking by 2.9 times. The combined effect of IL‐1GP and heavy smoking increased the risk of tooth loss by 7.7 times. The value of clinical parameters traditionally used to assign prognosis was found to be dependent on IL‐1 genotype and smoking status. In the model that included IL‐1 genotype and heavy smoking, none of the clinical parameters added significantly to the model for tooth loss while mobility, probing depth, crown‐to‐root ratio, and percent bone loss added significantly to the model, which included IL‐1 genotype in non‐smokers. IL‐1GP patients and patients who smoked heavily demonstrated a much worse tooth survival rate when compared to IL‐1 genotype‐negative patients and non‐smokers, respectively.Conclusions: Knowledge of the patient's IL‐1 genotype and smoking status will improve the clinician's ability to accurately assign prognosis and predict tooth survival. Clinical implications are as follows. Investigators were unable to judge which patients would be IL‐GP or negative based on their clinical presentation or family history of tooth loss due to periodontal disease. Since periodontal diseases are multifactorial, knowledge of the patient's genotype is more important in predicting future risk than explaining past disease. Knowledge of IL‐1 genotype status would be important in developing a treatment plan and predicting tooth survival for a new patient who smokes and presents with periodontal disease, especially if restorative care is needed. Knowledge of a maintenance patient's IL‐1 status would help target therapy for non‐responding areas; one would be less likely to take a “wait and see approach” with IL‐1GP patients. IL‐1 positive non‐smokers can be successfully treated and maintained over long periods of time. J Periodontol 1999;70: 49‐56.
Full‐Arch Restoration of the Jaw With Fixed Ceramo‐Metal Prosthesis: Late Implant Placement
Authors: Chaushu Gavriel , Schwartz‐Arad Devorah 
Published: February 2005

Background: The completely edentulous patient has few treatment options in conventional dentistry. When implants are considered, treatment plans range from a 2‐implant overdenture to a completely implant‐supported prosthesis. Fixed prosthesis is often the preferred selection of the edentulous patient. This study assesses the 5‐year cumulative survival rate of implants placed to support full‐arch fixed restoration.Methods: During 1990 to 1995, 171 implants were placed in 22 completely edentulous jaws of 20 patients. All patients were discharged wearing immediate dentures. The implants were analyzed as to the number of implants per jaw, implant location, length, and diameter.Results: The 5‐year cumulative survival rate was 89.9%. The mean number of implants per jaw was 7.7 for the maxilla and 8 for the mandible. In the maxilla, the preferred implant locations were the canines, centrals, laterals, and first premolars; in the mandible, they were the canines, laterals, and first molars. The mean implant length was 14.2 mm for the mandible and 13.2 mm for the maxilla. The mean implant diameter was 3.6 mm for the maxilla and 3.8 for the mandible.Conclusions: The results of the present study indicate that fixed full‐arch ceramo‐metal restorations can be a predictable implant treatment modality for the edentulous patient. J Periodontol 1999; 70: 90‐94.
Selecting a Practice Location: Factors That Periodontists May Consider
Authors: Waldman H. Barry 
Published: February 2005

Background: The decision to locate a periodontal practice is based upon a complex series of interrelated variables. An understanding of this process is essential if planning for the distribution of periodontists is to be considered.Methods: Non‐parametric statistical tests were used to determine the relationships between the rankings of states by periodontist‐to‐population ratios and 1) the availability of a periodontal training program, and 2) selected population demographic characteristics.Results: A statistically significant positive relationship was found between the ranking of states by periodontist‐to‐population ratios and 1) the availability of a periodontal training program; 2) per capita income; 3) per capita spending for health services; 4) availability of health insurance; and 5) the percentage of the population that is African‐American, Hispanic, and Asian‐American.Conclusions: This study provides a broad analysis of some of the factors in the practice location decision process. Further analysis at the local level (and for individual practitioners) is needed to better understand the decision process in the selection of a practice site. J Periodontol 1999; 70: 95‐99.
Effects of Occlusal Loading on Ankylosis, Bone, and Cementum Formation During Bone Morphogenetic Protein‐2‐Stimulated Periodontal Regeneration In Vivo
Authors: King Gaston N. , Hughes Francis J. 
Published: February 2005

Background: The purpose of this study was to investigate the influence of occlusal loading on recombinant human bone morphogenetic protein‐2 (BMP‐2)‐induced bone and cementum formation in a previously established rat model of periodontal regeneration during the early and late stages of wound healing.Methods: 64 Wistar rats were divided into 8 groups and had surgically created fenestrated defects on the right side of the mandible involving the removal of bone and exposure of the first and second molar roots. Four groups had their right maxillary molars extracted 2 weeks prior to surgery. Ten μl of 100 ug/ml BMP‐2 in a collagen membrane was placed in extracted (hypofunctional) and non‐extracted (functional) groups (BMPe and BMPf, respectively) while control groups had collagen membrane only (CONe and CONf). Groups were sacrificed at 10 (BMPe, BMPf, CONe, CONf) or 35 days (BMP35e, BMP35f, CON35e, CON350 postoperatively and tissues processed for histological examination. Transverse 5 μm sections were stained for identification of new bone, ankylosis and cementum formation.Results: At 10 days, CONe developed greater bone growth compared with CONf (P <0.05), while both BMP groups developed greater bone compared with controls, However, BMPe developed more ankylosis compared with both CONe and CONf while BMPf was significantly greater than CONf only (P < 0.05 ) . BMPf only developed significantly greater new cementum compared with controls. At 35 days, BMP35f developed greater bone growth compared with all other groups including BMP35e (P <0.05) and unlike results at 10 days, no differences were apparent between CON35f and CON35e. Unwanted bone growth beyond the defect margin anteriorly was significantly greater in BMP35f.Conclusions: Results suggest hypofunction stimulates early bone formation. Furthermore, hypofunction and BMP‐2 increase the development of transient ankylosis. However, after wound healing is complete, function augments the early effects of BMP‐2‐induced new bone growth indicating remodeling to physiological levels does not occur. Finally, occlusal loading is both an important stimulus for remodeling and establishment of the periodontal ligament space during early wound healing a s well a s enhancing BMP‐2‐induced cementogenesis. J Periodontol 1999;70:1125‐1135.
Human Periodontal Ligament Fibroblast Behavior on Chemically Conditioned Dentine: An In Vitro Study
Authors: Rompen Eric H. , Goffinet Gerhard H. , Nusgens Betty 
Published: February 2005

Background: Chemical root conditioning is widely used in an attempt to improve the outcome of regenerative periodontal surgery, but its effect on connective tissue cell proliferation and biosynthetic activity has been poorly studied. The goal of the present study was to test in vitro the consequences of conditioning human dentine by citric acid or minocycline on the behavior of attached human periodontal ligament (HPDL) cells in terms of proliferation, protein synthesis and morphological appearance.Methods: HPDL cells were seeded on powdered human dentine, either untreated or conditioned for 3 minutes with 3% citric acid or 2.5% minocycline HCl. Scanning (SEM) and transmission (TEM) electron microscopic observations were performed, and 3H‐thymidine and 3H‐proline incorporation tests were used to evaluate the proliferative and the biosynthetic activities.Results: Cell spreading was already evident and the penetration of cytoplasmic processes into dentinal tubules were frequently observed on all dentine types after 2 hours of attachment. After 24 hours of incubation, citric acid conditioning promoted an intense spreading of the cells, while minocycline HCl conditioning induced the formation of a dense feltwork of cellular processes. HPDL fibrolasts adherent to both types of surface‐conditioned dentine exhibited a significantly higher rate of proliferation (P <0.01) as well as a significantly higher level of total protein and of collagen synthesis (P <0.01) than on untreated dentine.Conclusions: These data suggest that during periodontal surgery a conditioning of the root surface by citric acid or by minocycline HCl could promote the attachment, the proliferation, and the biosynthetic activity of HDPL, prerequisites to periodontal regeneration. J Periodontol 1999;70:1144‐1152.
Antisense Oligonucleotide of Tissue Inhibitor of Metalloproteinase‐1 Induces the Plasminogen Activator Activity in Periodontal Ligament Cells
Authors: Shibata Yasuko , Takiguchi Hisashi , Abiko Yoshimitsu 
Published: February 2005

Background: Matrix metalloproteinases (MMPs), produced by both infiltrating and resident cells of the periodontium, play a role in physiologic and pathologic events. It is recognized that an imbalance between activated MMPs and their endogenous inhibitors leads to pathologic breakdown of the extracellular matrix during periodontitis. Although it is known that pro‐MMPs are activated by the plasminogen activator (PA)/plasmin system, and that the activated MMPs are inactivated by tissue inhibitor of metalloproteinases (TIMPs), participation of TIMPs in the PA/plasmin system has not been defined.Methods: We investigated the effects of the antisense oligonucleotide, consisting of a 21‐base sequence from the human TIMP‐1 gene including the first ATG initiation codon, on PA/plasmin activities in the cultured medium of periodontal ligament (PDL) fibroblastic cells. Antisense or sense oligonucleotides were directly added into cell‐cultured medium, and enzyme activities from the PDL cells were measured.Results: Antisense TIMP‐1 oligonucleotide specifically stimulated the PA activity dose‐dependently. Other oligonucleotides, sense TIMP‐1 or antisense TIMP‐2, did not affect PA activity in PDL cells. The PA activity increased by antisense TIMP‐1 oligonucleotide was due to an increase of urokinase‐type PA (uPA) protein, but not that of tissue‐type PA by means of immunoblotting. Furthermore, the stimulation of PA activity in the conditioned medium by adding antisense oligonucleotide for TIMP‐1 was not due to the decreasing levels of PA inhibitor‐1, an inhibitor of PA.Conclusions: TIMP‐1 controls the synthesis of uPA in the PDL cells. Control of the TIMP‐uPA system is important in inflammatory periodontal ligament healing. J Periodontol 1999;70:1158‐1165.