bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enamel Matrix Proteins and Guided Tissue Regeneration With Titanium‐Reinforced Expanded PolytetrafluoroethyleneMembranes in the Treatment of Infrabony Defects: A Comparative Controlled Clinical Trial
Authors: Zucchelli G. , Bernardi F. , Montebugnoli L. , De Sanctis M. 
Published: February 2005

Background: Several studies have documented the clinical efficacy of guided tissue regeneration (GTR) with non‐resorbable expanded polytetrafluoroethylene (ePTFE) membranes and enamel matrix proteins (EMP) in the treatment of infrabony defects. The objective of this controlled clinical study was to compare the clinical outcomes of 3 surgical modalities in the treatment of deep interproximal infrabony defects.Methods: Ninety (90) defects in 90 healthy subjects affected by chronic periodontitis were assigned to 1 of 3 treatment groups by blocking to prognostic variables. The test group was treated with the application of EMP and the simplified papilla preservation (SPP) technique; the second group was treated with titanium‐reinforced ePFTE membranes and the SPP technique; and the third group was treated with the SPP technique used as access flap control procedure. No differences were observed in terms of baseline oral hygiene and defect characteristics among the 3 groups, indicating that the blocking approach was effective. A stringent infection control program was adopted for 1 year.Results: The 1‐year results indicated that: 1) all treatment modalities resulted in clinically significant improvements in clinical attachment levels (CAL) and reduction in probing depth (PD); 2) a statistically significant treatment effect was demonstrated comparing the EMP test, the membrane control, and the flap control groups in terms of CAL gains; 3) both the EMP test and the membrane control groups showed significant CAL gains compared to the flap control group; 4) a statistically significantly greater amount of CAL gain was demonstrated in GTR‐treated compared to EMP‐treated patients; 5) deeper residual probing depths but smaller increases in gingival recession were demonstrated following EMP therapy; and 6) smoking habits reduced the clinical outcomes of both regenerative procedures.Conclusions: The use of a regenerative procedure is indicated in the treatment of deep vertical bony defects since both the regenerative techniques (GTR and EMD) in the present study resulted in clinically and statistically significant improvements in clinical parameters compared to the access flap procedure. The use of EMP can be helpful in esthetically‐sensitive sites and in reducing patient morbidity. J Periodontol 2002;73:3‐12.
Treatment of Gingival Recessions by Combined Periodontal Regenerative Technique, Guided Tissue Regeneration, and Subpedicle Connective Tissue Graft. A Comparative Clinical Study
Authors: Paolantonio Michele 
Published: February 2005

Background: Many surgical techniques have been shown to be effective in correcting gingival recessions by covering the exposed root with soft tissue; however, the thickness of the gingival tissue over the root surface probably plays an important role in preventing the recurrence of tissue recession. The aim of the present study was to compare the results of a mucogingival bilaminar technique (BT), guided tissue regeneration (GTR), and a combined periodontal regenerative technique (CPRT) in achieving root coverage and increasing the gingival thickness 1 year after surgical treatment.Methods: In 45 systemically healthy, non‐smoking patients aged 33.6 ± 4.3 years with no periodontal pockets >4 mm, a Miller's Class I or II gingival recession was treated for root coverage: 15 patients underwent BT (connective tissue with partial‐thickness double pedicle graft), 15 GTR by a bioabsorbable membrane, and 15 CPRT by a collagen membrane and collagen‐incorporated hydroxyapatite. Before and 1 year after surgical treatments, the following clinical parameters were recorded: gingival recession (GR), probing depth (PD), clinical attachment level (CAL), keratinized tissue width (KT), and gingival thickness (GT); the percentage of root coverage was also calculated and the data were statistically analyzed.Results: All 3 techniques yielded significant improvements in terms of GR decrease, CAL and KT gain, and GT increase compared to baseline values. Mean root coverage was 90.0%, 81.01%, and 87.12% in BT, GTR, and CPRT groups, respectively. Complete root coverage was observed in 60%, 40%, and 53.3% of subjects from the BT, GTR, and CPRT groups, respectively. No significant differences were observed among the 3 techniques in GR or CAL improvements; however, BT produced a significantly (P <0.01) greater increase of KT, and BT and CPRT groups showed a significantly (P <0.01) greater increase of GT compared to the GTR group.Conclusions: BT, GTR, and CPRT successfully treated gingival recession defects, obtaining comparable percentages of root coverage, but BT and CPRT created a thick gingival tissue significantly greater than that achieved with GTR. J Periodontol 2002;73:53‐62.
Effect of Recombinant Human Bone Morphogenetic Protein‐2/Absorbable Collagen Sponge (rhBMP‐2/ACS) on Healing in 3‐Wall Intrabony Defects in Dogs
Authors: Choi Seong‐Ho , Kim Chong‐Kwan , Cho Kyoo‐Sung , Huh Ji‐Sun , Sorensen Rachel G. , Wozney John M. , Wikesjö Ulf M.E. 
Published: February 2005

Background: Recombinant human bone morphogenetic protein‐2 (rhBMP‐2) in an absorbable collagen sponge (ACS) carrier is being evaluated as a candidate therapy for periodontal regeneration. The objective of this study was to evaluate regeneration of alveolar bone and cementum, and associated root resorption and ankylosis following surgical implantation of rhBMP‐2/ACS in a canine clinical model.Methods: Bilateral 3‐wall intrabony periodontal defects were surgically induced in the premolar region in the maxilla and mandible in 8 young adult Korean mongrel dogs. The defects in each animal received rhBMP‐2/ACS (rhBMP‐2 at 0.2 mg/ml, total implant volume/defect ~ 0.1 ml) or buffer/ACS, or served as sham‐operated controls. Surgeries were sequenced for each animal to provide postmortem observations following 8‐ and 24‐week healing intervals. Treatment outcomes were evaluated using clinical, radiographic, and histometric parameters.Results: Surgical implantation of rhBMP‐2/ACS resulted in accelerated enhanced bone formation in the 3‐wall intrabony periodontal defects but in no apparent enhancement of cementum regeneration. rhBMP‐2/ACS did not appear to be associated with aberrant healing events such as root resorption and ankylosis under these simulated clinical conditions.Conclusions: Surgical implantation of rhBMP‐2/ACS may be used safely to support regeneration of alveolar bone in intrabony periodontal defects in dogs without aberrant events such as root resorption or ankylosis complicating the regenerative procedure. rhBMP‐2/ACS does not appear to have a significant effect on cementum regeneration and formation of a functional periodontal ligament in this model. J Periodontol 2002;73:63‐72.
Systemic Release of Endotoxins Induced by Gentle Mastication: Association With Periodontitis Severity
Authors: Geerts Sabine O. , Nys Monique , De Mol Patrick , Charpentier Joseph , Albert Adelin , Legrand Victor , Rompen Eric H. 
Published: February 2005

Background: Periodontitis has recently been identified as a potential risk factor for systemic pathologies such as cardiovascular disease, the hypothesis being that periodontal pockets could release pro‐inflammatory bacterial components, for instance endotoxins, into the bloodstream. It is known that the oral cavity can be a source of circulating bacteria, but this has never been shown for bacterial endotoxins, and no evidence exists so far that the risk of systemic injury is related to the severity of periodontitis. The aim of the present study was to test the influence of gentle mastication on the occurrence of endotoxemia in patients with or without periodontal disease.Methods: A total of 67 subjects were periodontally examined and grouped according to their periodontal status. This classification was based on an original index of severity of periodontal disease (periodontal index for risk of infectiousness, PIRI) aimed at reflecting the individual risk of systemic injury from the periodontal niches. Thus, the patients were classified into 3 risk groups: low, PIRI = 0; n = 25; moderate, 1 ≤PIRI ≤5, n = 27; and high 6 ≤PIRI ≤10, n = 15. Blood samples were collected before and 5 to 10 minutes after a standardized session of gentle mastication for detection of circulating endotoxins. Blood samples were tested with a chromogenic limulus amoebocyte lysate assay.Results: Overall, blood levels of endotoxin after mastication were found to be significantly higher than before mastication (0.89 ± 3.3 pg/ml versus 3.0 ± 5.8 pg/ml; P = 0.0002). Likewise, the incidence of positive endotoxemia rose from 6% before mastication to 24% after mastication (P = 0.001). When accounting for the PIRI index, endotoxin levels and positive endotoxemia proved to be significantly higher in patients with severe periodontal disease than in the subjects with low or moderate periodontitis.Conclusions: Gentle mastication is able to induce the release of bacterial endotoxins from oral origin into the bloodstream, especially when patients have severe periodontal disease. This finding suggests that a diseased periodontium can be a major and underestimated source of chronic, or even permanent, release of bacterial pro‐inflammatory components into the bloodstream. J Periodontol 2002;73:73‐78.
An Organotypic In Vitro Model That Mimics the Dento‐Epithelial Junction
Authors: Oksanen Jaana , Hormia Marketta 
Published: February 2005

Background: The dento‐epithelial junction forms the primary periodontal defense structure against oral microbes. The cells of the junctional epithelium (JE) attach both to a basement membrane (BM) facing the connective tissue and to a hard dental tissue by structurally similar but molecularly distinct mechanisms. Here we describe a new organotypic cell culture model for the dento‐epithelial junction comprising not only epithelial and mesenchymally derived components, but also a tooth surface equivalent.Methods: Rat palatal keratinocytes were seeded on fibroblast‐collagen gels. A tooth slice was placed on top of the epithelial cells and the multilayer cultures were grown at the air‐liquid interface. Formation of the epithelial structures, BM components, and the epithelial attachment to the tooth surface were studied by immunofluorescence and light and electron microscopy. The findings were compared to the structure of the dento‐epithelial junction in vivo.Results: A well‐differentiated stratified epithelium was formed. Under the tooth slice the epithelium remained thin and non‐differentiated. Attachment of the epithelial cells to the tooth surface was mediated by hemidesmosomes (HDs) as in vivo. Laminin‐5 (Ln‐5) was present in the extracellular matrix (ECM) between the tooth and the epithelium as well as in the BM structure between the epithelium and the fibroblast‐collagen matrix. Instead, Ln‐10/11 was present only at the mesenchymal tissue side as is known to be the case in vivo.Conclusions: The organotypic model presented expresses the characteristic structural and molecular features of the dentoepithelial junction and may be applied for studying physiological and pathological processes in the epithelial attachment. J Periodontol 2002;73:86‐93.
Histological Comparison of Healing Extraction Sockets Implanted With Bioactive Glass or Demineralized Freeze‐Dried Bone Allograft: A Pilot Study
Authors: Froum Stuart , Cho Sang‐Choon , Rosenberg Edwin , Rohrer Michael , Tarnow Dennis 
Published: February 2005

Background: Various materials have been used immediately following tooth extraction to fill and/or cover the socket in an attempt to limit or prevent ridge resorption. The purpose of the present pilot study was to establish a reliable model to investigate the effect of various bone graft and bone replacement materials on extraction socket healing. This study also compared healing extraction sockets 6 to 8 months postimplantation of a bioactive glass (BG) or demineralized freeze‐dried bone allograft (DFDBA) to an unfilled socket control (C).Methods: Following tooth extraction, a total of 30 sockets in 19 patients were randomly divided into 3 treatment groups: 10 sockets received BG, 10 sockets DFDBA, and 10 sockets served as unfilled controls. Primary coverage was achieved by flap advancement over each socket. Six to 8 months postextraction at time of implant placement, histological cores of the treatment sites were obtained. These cores were processed, undecalcified sections prepared and stained with Stevenel blue/van Gieson's picric fuchsin, and histomorphometrically analyzed. Vital bone, connective tissue and marrow, and residual graft particles were reported as a percentage of the total core.Results: A model system was described in humans and used to evaluate the healing response in the 3 treatment groups. Results concluded that mean vital bone present was 59.5% for BG‐, 34.7% for DFDBA‐, and 32.4% for C‐treated sites. These differences were not statistically significant. However, the residual implant material was significantly higher in DFDBA‐treated (13.5%) versus BG‐treated sockets (5.5%).Conclusions: Although the differences in percent vital bone were not statistically significant among the 3 treatment groups in this pilot study, BG material was observed to act as an osteoconductive material which had a positive effect on socket healing at 6 to 8 months postextraction. Further research following implant placement in treated and control sockets is warranted to determine if bone implant contact is improved in BG‐filled versus unfilled sockets. J Periodontol 2002;73:94‐102.
Specific Fibronectin Fragments as Markers of Periodontal Disease Status
Authors: Huynh Quang Ngoc , Wang Shaohui , Tafolla Elizabeth , Gansky Stuart A. , Kapila Sunil , Armitage Gary C. , Kapila Yvonne L. 
Published: February 2005

Background: The diagnosis of progressing periodontal disease typically relies on retrospective methods that detect changes in the amount of periodontal breakdown. Fibronectin (FN) fragments are found in vivo in association with periodontal disease, and specific FN fragments compromise periodontal ligament cell functions in vitro. The overall goal of this crosssectional study was to determine whether specific FN fragments are present in gingival crevicular fluid (GCF) and can be used as markers for periodontal disease status. The eventual goal is to test these FN fragments in a longitudinal study as potential markers of disease activity.Methods: GCF was collected from 94 subjects with untreated periodontitis from clinically healthy, mild/moderate periodontitis, and severe periodontitis sites. Sites were defined on the basis of clinical criteria, including gingival bleeding index, probing depth, and clinical attachment level. Western immunoblotting was used to detect FN fragments in GCF using antibodies to specific FN domains, including the collagen/gelatin‐, central cell‐, and carboxyl terminal heparin‐binding domains, plus the CS‐1 site on the alternatively spliced V region and the EIIIA region. FN fragments identified by immunoblotting and analyzed by NIH image software were scored based on pixel intensity and an ordinal grade scale.Results: We identified several fragments highly associated with severe periodontitis sites, including 40‐kDa, 120‐kDa, and 68‐kDa fragments.Conclusions: This study demonstrates that specific FN fragments are markers for periodontal disease status and supports the role of FN fragments as potential components in the pathogenesis of periodontal disease. J Periodontol 2002;73:1101‐1110.
Influence of the Size of the Microgap on Crestal Bone Levels in Non‐Submerged Dental Implants: A Radiographic Study in the Canine Mandible
Authors: King Gaston N. , Hermann Joachim S. , Schoolfield John D. , Buser Daniel , Cochran David L. 
Published: February 2005

Background: Accumulating evidence suggests that alveolar crestal bone resorption occurs as a result of the microgap that is present between the implant–abutment interface in dental implants. The objective of this longitudinal radiographic study was to determine whether the size of the interface or the microgap between the implant and abutment influences the amount of crestal bone loss in unloaded non‐submerged implants.Methods: Sixty titanium implants having sandblasted with large grit, acid‐etched (SLA) endosseous surfaces were placed in edentulous mandibular areas of 5 American fox hounds. Implant groups A, B, and C had a microgap between the implant–abutment connection of <10 µm, 50 µm, or 100 µm, respectively, as did groups D, E, and F, respectively. Abutments were either welded (1‐piece) in groups A, B, and C or nonwelded (2‐piece screwed) in D, E, and F. All abutment interfaces were placed 1 mm above the alveolar crest. Radiographic assessment was undertaken to evaluate peri‐implant crestal bone levels at baseline and at 1, 2, and 3 months after implant placement whereupon all animals were sacrificed.Results: The size of the microgap at the abutment/implant interface had no significant effect upon crestal bone loss. At 1 month, most implants developed crestal bone loss compared with baseline levels. However, during this early healing period, the non‐welded group (D, E, and F) showed significantly greater crestal bone loss from baseline to one month (P <0.04) and 2 months (P <0.02) compared with the welded group (A, B, and C). No significant differences were observed between these 2 groups at 3 months (P >0.70).Conclusions: Crestal bone loss was an early manifestation of wound healing occurring after 1 month of implant placement. However, the size of the microgap at the implant‐abutment interface had no significant effect upon crestal bone resorption. Thus, 2‐piece non‐welded implants showed significantly greater crestal bone loss compared with 1‐piece welded implants after 1 and 2 months suggesting that the stability of the implant/abutment interface may have an important early role to play in determining crestal bone levels. At 3 months, this influence followed a similar trend but was not observed to be statistically significant. This finding implies that implant configurations incorporating interfaces will be associated with biological changes regardless of interface size and that mobility between components may have an early influence on wound healing around the implant. J Periodontol 2002;73:1111‐1117.
The Role of CD4+ Cells In Vivo on the Induction of the Immune Response to Porphyromonas gingivalis in Mice
Authors: Sosroseno Wihaskoro , Bird Philip S. , Gemmell Erica , Seymour Gregory J. 
Published: February 2005

Background: It has previously been suggested that CD4+ T cells play a pivotal role in regulating the immune response to periodontal pathogens. The aim of the present study therefore was to determine delayed type hypersensitivity (DTH), spleen cell proliferation, serum and splenic anti‐Porphyromonas gingivalis antibody levels, and lesion sizes following challenge with viable P. gingivalis in CD4‐depleted BALB/c mice immunized with P. gingivalis outer membrane proteins (OMP).Methods: Four groups of BALB/c mice were used. Groups 1 and 2 were injected intraperitoneally (ip) with saline for 3 consecutive days and then weekly throughout the experiment. Groups 3 and 4 were injected ip with rat immunoglobulin and a monoclonal rat anti‐mouse CD4 antibody, respectively. Two days later, group 1 mice were injected ip with saline only, while all the other groups were immunized ip with P. gingivalis OMP weekly for 3 weeks. One week later following the last immunization of OMP, 3 separate experiments were conducted to determine: 1) the DTH response to P. gingivalis OMP by measuring footpad swelling; 2) the levels of antibodies to P. gingivalis in serum samples and spleen cell cultures using an enzymelinked immunosorbent assay, as well as spleen cell proliferation after stimulation with OMP; and 3) the lesion sizes after a subcutaneous challenge with viable P. gingivalis cells.Results: In CD4+ T‐cell–depleted mice (group 4), the DTH response and antigen‐stimulated cell proliferation were signifi‐cantly suppressed when compared to groups 2 and 3. Similarly, the levels of serum and splenic IgM, IgG, and all IgG subclass antibodies to P. gingivalis OMP were depressed. Delayed healing of P. gingivalis‐induced lesions was also observed in the CD4+ T‐cell–depleted group.Conclusions: This study has shown that depletion of CD4+ T cells prior to immunization with P. gingivalis OMP led to the suppression of both the humoral and cell‐mediated immune response to this microorganism and that this was associated with delayed healing. These results suggest that the induction of the immune response to P. gingivalis is a CD4+ T‐cell–dependent mechanism and that CD4+ T cells are important in the healing process. J Periodontol 2002;73:1133‐1140.
The Effect of Duration and Force of Mechanical Toothbrushing Stimulation on Proliferative Activity of the Junctional Epithelium
Authors: Tomofuji Takaaki , Morita Manabu , Horiuchi Masazumi , Sakamoto Tomonori , Ekuni Daisuke , Yamamoto Tatsuo , Watanabe Tatsuo 
Published: February 2005

Background: Gingival bleeding is frequently accompanied by an ulcerated epithelium, with repair depending on the proliferative activity of the epithelial cells. The present study examined the proliferative activity of the junctional epithelium (JE) under several different methods of toothbrushing stimulation.Methods: Twelve dogs were used in this 3‐week experiment. Prior to the experiment, all teeth underwent daily removal of plaque and calculus using a scaler. Teeth were then divided into quadrants: 9 teeth in 3 quadrants (test, 3 per quadrant) were mechanically stimulated by toothbrushing for various time intervals (10, 20, or 40 seconds) and at various forces (100, 200, or 250 gf). The 3 teeth in the fourth quadrant served as controls. The proliferative activity of the basal cells of the junctional epithelium was evaluated for expression of proliferating cell nuclear antigen (PCNA). The numbers of PCNA‐positive basal cells and total basal cells were counted, and the width of the junctional epithelium was measured.Results: Toothbrushing force significantly affected the PCNApositive basal cell ratio (P <0.05). The 200 g toothbrushing force produced the highest PCNA‐positive basal cell ratio, which was significantly higher than that using the 100 g force (P <0.05).Conclusion: In junctional epithelium stimulated with a toothbrush, the PCNA‐positive basal cell ratio is more sensitive to toothbrushing force than to duration. J Periodontol 2002;73:1149‐1152.