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Biomedical subjects

W V Giannobile

Publications and source records attributed to W V Giannobile.

At least 19 recordsLinked to original sources
PubMed2006

Craniofacial tissue engineering by stem cells.

Craniofacial tissue engineering promises the regeneration or de novo formation of dental, oral, and craniofacial structures lost to congenital anomalies, trauma, and diseases. Virtually all craniofacial structures are derivatives of mesenchymal cells. Mesenchymal stem cells are the offspring of mesenchymal cells following asymmetrical division, and reside in various craniofacial structures in the adult. Cells with characteristics of adult stem cells have been isolated from the dental pulp, the deciduous tooth, and the periodontium. Several craniofacial structures--such as the mandibular condyle, calvarial bone, cranial suture, and subcutaneous adipose tissue--have been engineered from mesenchymal stem cells, growth factor, and/or gene therapy approaches. As a departure from the reliance of current clinical practice on durable materials such as amalgam, composites, and metallic alloys, biological therapies utilize mesenchymal stem cells, delivered or internally recruited, to generate craniofacial structures in temporary scaffolding biomaterials. Craniofacial tissue engineering is likely to be realized in the foreseeable future, and represents an opportunity that dentistry cannot afford to miss.

Absorbable Implants↗
PubMed2005

Current concepts in periodontal bioengineering.

Repair of tooth supporting alveolar bone defects caused by periodontal and peri-implant tissue destruction is a major goal of reconstructive therapy. Oral and craniofacial tissue engineering has been achieved with limited success by the utilization of a variety of approaches such as cell-occlusive barrier membranes, bone substitutes and autogenous block grafting techniques. Signaling molecules such as growth factors have been used to restore lost tooth support because of damage by periodontal disease or trauma. This paper will review emerging periodontal therapies in the areas of materials science, growth factor biology and cell/gene therapy. Several different polymer delivery systems that aid in the targeting of proteins, genes and cells to periodontal and peri-implant defects will be highlighted. Results from preclinical and clinical trials will be reviewed using the topical application of bone morphogenetic proteins (BMP-2 and BMP-7) and platelet-derived growth factor-BB (PDGF) for periodontal and peri-implant regeneration. The paper concludes with recent research on the use of ex vivo and in vivo gene delivery strategies via gene therapy vectors encoding growth promoting and inhibiting molecules (PDGF, BMP, noggin and others) to regenerate periodontal structures including bone, periodontal ligament and cementum.

Animals↗
PubMed2004

Noggin gene delivery inhibits cementoblast-induced mineralization.

Bone morphogenetic proteins (BMPs) are known to promote periodontal tissue regeneration, while noggin inhibits the biological activities of BMP-2, -4, and -7. To investigate the effect of BMPs and noggin gene transfer on cementogenesis, we used cloned murine cementoblasts (OCCM). Cells were transduced using adenoviruses encoding BMP-7 (Ad-BMP-7), noggin devoid of the heparin binding site (Ad-NOGDeltaB2), or a control adenovirus encoding green fluorescent protein (Ad-GFP). Cells were seeded into 3D polymer scaffolds and implanted into SCID mice to determine the in vivo mineral-inducing ability of the cells. Cells transduced with Ad-NOGDeltaB2 at 3 and 6 weeks postimplantation exhibited reduced mineral formation compared with all other groups. Although gene expression of osteocalcin and bone sialoprotein increased after Ad-BMP-7 transduction in vitro, following BMP-7 gene transfer in vivo, transcripts for OCN and BSP were not significantly different from controls, and mineral density was not significantly increased compared with Ad-GFP and NT groups. These results indicate that in mature cementoblast populations, gene transfer of noggin inhibits biomineralization induced by cementoblasts, whereas exogenous BMP has minimal effects on mineralization.

Animals↗
PubMed2004

Effect of systemic matrix metalloproteinase inhibition on periodontal wound repair: a proof of concept trial.

BACKGROUND: The adjunctive use of matrix metalloproteinase (MMP) inhibitors with scaling and root planing (SRP) promotes new attachment in patients with periodontal disease. This pilot study was designed to examine aspects of the biological response brought about by the MMP inhibitor low dose doxycycline (LDD) combined with access flap surgery (AFS) on the modulation of periodontal wound repair in patients with severe chronic periodontitis. METHODS: Twenty-four subjects were enrolled into a 12-month, randomized, placebo-controlled, double-masked trial to evaluate clinical, biochemical, and microbial measures of disease in response to 6 months therapy of either placebo capsules + AFS or LDD (20 mg b.i.d.) + AFS. Clinical measures including probing depth (PD), clinical attachment levels (CAL), and bleeding on probing (BOP) as well as gingival crevicular fluid bone marker assessment (ICTP) and microbial DNA analysis (levels and proportions of 40 bacterial species) were performed at baseline and 3, 6, 9, and 12 months. RESULTS: Patients treated with LDD + AFS showed more potent reductions in PD in surgically treated sites of >6 mm (P<0.05, 12 months). Furthermore, LDD + AFS resulted in greater reductions in ICTP levels compared to placebo + AFS. Rebounds in ICTP levels were noted when the drug was withdrawn. No statistical differences between the groups in mean counts were found for any pathogen tested. CONCLUSIONS: This pilot study suggests that LDD in combination with AFS may improve the response of surgical therapy in reducing probing depth in severe chronic periodontal disease. LDD administration also tends to reduce local periodontal bone resorption during drug administration. The use of LDD did not appear to contribute to any significant shifts in the microbiota beyond that of surgery alone.

Adult↗
PubMed2003

Cementum engineering with three-dimensional polymer scaffolds.

Cloned cementoblasts (OCCMs), periodontal ligament fibroblasts (SV-PDLs), and dental follicle (SV-F) cells obtained from mice were used as a tool to study periodontal tissue engineering. OCCM, SV-PDL, and SV-F cells were seeded onto three-dimensional poly lactic-co-glycolic acid (PLGA) scaffolds and cultured with the use of bioreactors or implanted subcutaneously in severe combined immune deficiency (SCID) mice for up to 6 weeks. We explored the behavior of these cells in porous PLGA sponges by cell growth, expression of mineral-associated genes using reverse transcriptase polymerase chain reaction, and mineralization by histologic analysis in vitro and in vivo. Results indicated that cells attached to PLGA scaffolds under either static or dynamic conditions in vitro. Only OCCM implants, retrieved from both in vitro bioreactors and SCID mice at 3-and 6-weeks post-cell implantation exhibited mineral formation. Types I and XII collagens, osteocalcin, and bone sialoprotein genes were detected in all implants retrieved from SCID mice. These results suggest that delivery of selected cells via PLGA scaffolds may serve as a viable approach for promoting periodontal tissue regeneration.

Animals↗
PubMed2003

Gene therapy of bone morphogenetic protein for periodontal tissue engineering.

BACKGROUND: The reconstruction of lost periodontal support including bone, ligament, and cementum is a major goal of therapy. Bone morphogenetic proteins (BMPs) have shown much potential in the regeneration of the periodontium. Limitations of BMP administration to periodontal lesions include need for high-dose bolus delivery, BMP transient biological activity, and low bioavailability of factors at the wound site. Gene transfer offers promise as an alternative treatment strategy to deliver BMPs to periodontal tissues. METHODS: This study utilized ex vivo BMP-7 gene transfer to stimulate tissue engineering of alveolar bone wounds. Syngeneic dermal fibroblasts (SDFs) were transduced ex vivo with adenoviruses encoding either green fluorescent protein (Ad-GFP or control virus), BMP-7 (Ad-BMP-7), or an antagonist of BMP bioactivity, noggin (Ad-noggin). Transduced cells were seeded onto gelatin carriers and then transplanted to large mandibular alveolar bone defects in a rat wound repair model. RESULTS: Ad-noggin treatment tended to inhibit osteogenesis as compared to the control-treated and Ad-BMP-7-treated specimens. The osseous lesions treated by Ad-BMP-7 gene delivery demonstrated rapid chrondrogenesis, with subsequent osteogenesis, cementogenesis and predictable bridging of the periodontal bone defects. CONCLUSION: These results demonstrate the first successful evidence of periodontal tissue engineering using ex vivo gene transfer of BMPs and offers a new approach for repairing periodontal defects.

Adenoviridae↗
PubMed2002

Effect of locally delivered minocycline microspheres on markers of bone resorption.

BACKGROUND: Gingival crevicular fluid (GCF) biomarkers associated with bone resorption may be useful to determine periodontal disease status and response to therapy. The pyridinoline cross-linked carboxy-terminal telopeptide of type I collagen (ICTP), a bone-specific degradation product, and interleukin 1-beta (IL-1), a potent bone-resorptive cytokine, have both been associated with periodontal disease activity. Minocycline is a tetracycline derivative possessing antimicrobial effects on periodontal pathogens and inhibitory properties on matrix metalloproteinases (MMPs) associated with tissue destruction. The aim of this study was to evaluate the effect of periodontal treatment in the form of scaling and root planing (SRP) and locally administered minocycline microspheres on the GCF levels of ICTP and IL-1. METHODS: Forty-eight chronic periodontitis patients were randomly assigned to 2 groups (SRP plus subgingival application of vehicle control [SRP + V], or SRP plus subgingival application of minocycline microspheres [SRP + M]) and monitored at 8 sites per subject at baseline and 1, 3, and 6 months. Four shallow (PD < or = 3 mm) and 4 deep (PD > or = 5 mm) sites were evaluated for both marker levels and for probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP). Eight periodontally healthy control subjects with no probing depths >3 mm and no loss of attachment were also monitored at the same time intervals. GCF levels of ICTP and IL-1 were determined using radioimmunoassay and enzyme-linked immunosorbent assay techniques, respectively. RESULTS: Significant differences (P<0.001) in GCF levels of ICTP and IL-1 were found between deep and shallow sites at all time points in both treatment groups. In addition, healthy subjects demonstrated significantly reduced levels of both markers compared to both shallow and deep sites in periodontitis patients (P <0.001). Only the SRP + M treated patients exhibited significant reductions (P <0.05) in both ICTP and IL-1 levels 1 month after treatment. Furthermore, the SRP + M group demonstrated significantly lower IL-1 levels (P <0.02) at 1 month compared to the SRP + V group. CONCLUSIONS: Results of this study indicate that GCF levels of ICTP and IL-1 correlate with clinical measures of periodontal disease and may aid in assessing disease status and response to periodontal therapy. Furthermore, local administration of minocycline microspheres led to a potent short-term reduction in GCF IL-1 levels. Additional studies are needed to address whether repeated administration of scaling and root planing along with minocycline microspheres will achieve long-term reductions in GCF ICTP and IL-1 levels.

Administration, Topical↗
PubMed2001

Gene transfer and expression of platelet-derived growth factors modulate periodontal cellular activity.

Platelet-derived growth factor (PDGF) is a potent stimulator of wound healing. PDGF gene therapy may promote greater periodontal regeneration than local protein application, due to sustained growth factor delivery to the target tissue. This investigation tested the ability of recombinant adenoviruses (rAds) encoding PDGF-A or PDGF-1308 (a PDGF-A dominant-negative mutant that disrupts endogenous PDGF bioactivity) to affect cells derived from the periodontium. Osteoblasts, periodontal ligament fibroblasts, and gingival fibroblasts were transduced with rAds, and gene expression, DNA synthesis, and cell proliferation were evaluated. The results revealed strong message for the PDGF-A gene for 7 days following gene delivery. Ad2/PDGF-A enhanced the mitogenic and proliferative response in all cell types, while Ad2/PDGF-1308 potently inhibited mitogenesis and proliferation. In conclusion, Ad2/PDGF can effectively transduce cells derived from the periodontium and promote biological activity equivalent to PDGF-AA. These studies support the potential use of gene therapy for sustained PDGF release in periodontal tissues.

Adenoviridae↗
PubMed2001

Treatment of periodontitis by local administration of minocycline microspheres: a controlled trial.

BACKGROUND: Periodontitis is an inflammatory condition of tooth-supporting tissues that is usually treated by mechanical removal of plaque and microorganisms that adhere to teeth. This treatment, known as scaling and root planing, is not optimally effective. Adjunctive therapy with locally delivered antimicrobials has resulted in improved clinical outcomes such as probing depth reduction. This article reports on the efficacy and safety of locally administered microencapsulated minocycline. METHODS: Seven hundred forty-eight (748) patients with moderate to advanced periodontitis were enrolled in a multi-center trial and randomized to 1 of 3 treatment arms: 1) scaling and root planing (SRP) alone; 2) SRP plus vehicle; or 3) SRP plus minocycline microspheres. The primary outcome measure was probing depth reduction at 9 months. Clinical assessments were performed at baseline and 1, 3, 6, and 9 months. RESULTS: Minocycline microspheres plus scaling and root planing provided substantially more probing depth reduction than either SRP alone or SRP plus vehicle. The difference reached statistical significance after the first month and was maintained throughout the trial. The improved outcome was observed to be independent of patients' smoking status, age, gender, or baseline disease level. There was no difference in the incidence of adverse effects among treatment groups. CONCLUSIONS: Scaling and root planing plus minocycline microspheres is more effective than scaling and root planing alone in reducing probing depths in periodontitis patients.

Administration, Topical↗
PubMed2001

Platelet-derived growth factor (PDGF) gene delivery for application in periodontal tissue engineering.

BACKGROUND: A challenge in the reconstruction of periodontal structures is the targeted delivery of growth-promoting molecules to the tooth root surface. Polypeptide growth factors such as platelet-derived growth factor (PDGF) stimulate both cementogenesis and osteogenesis. Recent advances in gene therapy offer the advantage of delivering recombinant proteins to tissues for extended periods of time in vivo. METHODS: Recombinant adenoviral vectors encoding for the PDGF-A gene were constructed to allow delivery of PDGF transgenes to cells. The recombinant adenoviruses were assembled using the viral backbone of Ad2/CMV/EGFP and replacing GFP (reporter gene encoding green fluorescent protein driven by the cytomegalovirus promoter [CMV] within adenovirus type 2) with the PDGF-A gene. Root lining cells (cloned cementoblasts) were transduced with Ad2/PDGF-A and evaluated for gene expression, DNA synthesis, and cell proliferation. PDGF-inducible genes, c-myc and osteopontin, were also evaluated following gene delivery of Ad2/PDGF-A. RESULTS: The results revealed high level transduction of cementoblasts by gene transfer for 7 days as evidenced by flow cytometry and Northern blotting. Cementoblast DNA synthesis and subsequent proliferation were stimulated by Ad2/PDGF-A at levels equal to or greater than continuous rhPDGF-AA application. Strong message for the PDGF-A gene and protein as evidenced by Northern blotting and immunocytochemistry was noted. Furthermore, the potent induction of c-myc and osteopontin mRNA was found after PDGF gene delivery to cementoblasts. CONCLUSIONS: These findings demonstrate that gene delivery of platelet-derived growth factor stimulates cementoblast activity that is sustained above that of rhPDGF-AA application. The use of gene therapy as a mode of growth factor delivery offers a novel approach to periodontal tissue engineering.

Adenoviridae↗
PubMed2001

Effect of non-surgical periodontal therapy on C-telopeptide pyridinoline cross-links (ICTP) and interleukin-1 levels.

BACKGROUND: Biochemical markers harvested from gingival crevicular fluid (GCF) may be useful to identify and predict periodontal disease progression and to monitor the response to treatment. C-telopeptide pyridinoline cross-links (ICTP), a host-derived breakdown product specific for bone, and interleukin-1beta (IL-1), a potent bone-resorptive cytokine, have been associated with periodontal tissue destruction. The aim of this study was to examine the effect of non-surgical periodontal therapy on GCF levels of ICTP and IL-1. METHODS: Twenty-five chronic periodontitis subjects were monitored at 8 sites per subject at baseline prior to scaling and root planing and 1, 3, and 6 months after therapy. Four shallow (probing depths < 4 mm) and 4 deep (probing depths > or = 5 mm) sites were monitored for both marker levels and clinical parameters. GCF was collected for 30 seconds on paper strips, and levels of ICTP and IL-1 were determined using radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA) techniques, respectively. Clinical measurements included probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP). RESULTS: Deep sites exhibited significantly (P<0.001) higher ICTP and IL-1 levels compared to shallow sites at all time intervals. ICTP demonstrated a stronger association to clinical parameters than IL-1 including a modest correlation (r = 0.40, P<0.001) between ICTP and attachment loss. Significant improvements in PD, CAL, and BOP were observed at 1, 3, and 6 months in all sites (P<0.01). However, non-surgical mechanical therapy did not significantly reduce ICTP and IL-1 levels over the 6-month period. Further examination of subjects based on smoking status revealed that ICTP levels were significantly reduced at 3 and 6 months and IL-1 levels reduced at 3 months among non-smokers only. CONCLUSIONS: A single episode of non-surgical mechanical therapy did not significantly reduce biochemical markers associated with bone resorption in patients exhibiting chronic periodontitis. Future longitudinal studies are warranted to specifically evaluate the relationship between C-telopeptide pyridinoline cross-links and periodontal disease progression.

Adult↗
PubMed2000

Growth factors regulate expression of mineral associated genes in cementoblasts.

BACKGROUND: Knowledge of the responsiveness of cells within the periodontal region to specific bioactive agents is important for improving regenerative therapies. The aim of this study was to determine the effect of specific growth factors, insulin-like growth factor-I (IGF-I), platelet-derived growth factor-BB (PDGF-BB), and transforming growth factor-beta (TGF-beta) on cementoblasts in vitro and ex vivo. METHODS: Osteocalcin (OC) promoter driven SV40 transgenic mice were used to obtain immortalized cementoblasts. Growth factor effects on DNA synthesis were assayed by [3H]-thymidine incorporation. Northern analysis was used to determine the effects of growth factors on gene expression profile. Effects of growth factors on cementoblast induced biomineralization were determined in vitro (von Kossa stain) and ex vivo (re-implantation of cells in immunodeficient (SCID) mice). RESULTS: All growth factors stimulated DNA synthesis compared to control. Twenty-four hour exposure of cells to PDGF-BB or TGF-beta resulted in a decrease in bone sialoprotein (BSP) and osteocalcin (OCN) mRNAs while PDGF-BB also increased osteopontin (OPN) mRNA. Cells exposed to IGF-I for 24 hours exhibited decreased transcripts for OCN and OPN with an upregulation of BSP mRNA noted at 72 hours. In vitro mineralization was inhibited by continuous application of PDGF-BB or TGF-beta, while cells exposed to these factors prior to implantation into SCID mice still promoted biomineralization. CONCLUSIONS: These data indicate IGF-I, PDGF-BB, and TGF-beta influence mitogenesis, phenotypic gene expression profile, and biomineralization potential of cementoblasts suggesting that such factors alone or in combination with other agents may provide trigger factors required for regenerating periodontal tissues.

Animals↗
PubMed1999

C-telopeptide pyridinoline cross-links. Sensitive indicators of periodontal tissue destruction.

C-telopeptides and related pyridinoline cross-links of bone Type I collagen are sensitive markers of bone resorption in osteolytic diseases such as osteoporosis and osteoarthritis. We have studied the release of C-telopeptide pyridinoline crosslinks of Type I collagen as measures of bone destruction in periodontal disease. Studies in preclinical animal models and humans have demonstrated the relationship between radiographic bone loss and crevicular fluid C-telopeptide levels. We have recently found that C-telopeptide levels correlate strongly with microbial pathogens associated with periodontitis and around endosseous dental implants. Host-modulation of bone-related collagen breakdown has been shown by studies in humans demonstrating that MMP inhibition blocks tissue destruction and release of C-telopeptides in patients with active periodontal disease.

Alveolar Bone Loss↗
PubMed1999

Evolution of periodontal regeneration: from the roots' point of view.

Tissues lost as a consequence of periodontal diseases, i.e. bone, cementum and a functional periodontal ligament (PDL), can be restored to some degree. Nevertheless, results are often disappointing. There is a need to develop new paradigms for regenerating periodontal tissues that are based on an understanding of the cellular and molecular mechanisms regulating the development and regeneration of periodontal tissues. As one approach we have developed strategies for maintaining cementoblasts in culture by first determining the gene profile for these cells in situ. Next, cells were immortalized in vitro using SV 40 large T antigen (SV40 Tag) or by using mice containing transgenes enabling cellular immortality in vitro. Cementoblasts in vitro retained expression of genes associated with mineralized tissues, bone sialoprotein and osteocalcin, that were not linked with periodontal fibroblasts either in situ or in vitro. Further, cementoblasts promoted mineralization in vitro as measured by von Kossa and ex vivo using a severely compromised immunodeficient (SCID) mouse model. These cells responded to growth factors by eliciting changes in gene profile and mitogenesis and to osteotropic hormones by evoking changes in gene profile and ability to induce mineral nodule formation in vitro. The ultimate goal of these studies is to provide the knowledge base required for designing improved modalities for use in periodontal regenerative therapies.

Animals↗
PubMed1999

The short-term effect of apically repositioned flap surgery on the composition of the subgingival microbiota.

The purpose of this investigation was to examine the short-term effect of apically repositioned flap surgery on clinical and microbiologic parameters in patients with adult periodontitis. A total of 11 patients with moderate to advanced periodontitis received apically repositioned flap surgery. Subjects were monitored during a 3-month pretreatment phase, the baseline surgical phase, and for 3 months post-surgery. Clinical assessments including plaque accumulation, gingival redness, suppuration, bleeding on probing, pocket depth, and attachment level were made at 6 sites per tooth. Subgingival plaque samples were taken from the mesial aspect of each tooth and the presence and levels of 29 subgingival taxa were determined using whole genomic DNA probes and checkerboard DNA-DNA hybridization. The mean levels and percentage of sites colonized by each species (prevalence) were computed for each subject at each visit. After surgery, there was a significant decrease in mean pocket depth and percentage of sites exhibiting gingival redness. Significant decreases were seen in the percentage of sites that had attachment levels < 4 mm, with a significant increase in the percentage of sites with attachment levels of 4 to 6 mm after therapy. The mean total DNA probe count for all bacterial species was significantly decreased by both scaling and root planing and surgical therapy. P gingivalis and B forsythus, 2 bacteria previously shown to be susceptible to mechanical therapy, exhibited statistically significant decreases in mean total DNA probe count. Because surgical therapy decreased levels of the suspected periodontal pathogens C rectus, P nigrescens, and C gracilis, it may be speculated that there was a potential added beneficial effect of surgery on the periodontal microbiota.

Actinomyces↗
PubMed1998

C-telopeptide pyridinoline cross-links (ICTP) and periodontal pathogens associated with endosseous oral implants.

Detection of periodontal or peri-implant sites exhibiting progressing disease or those at risk of deterioration has proven difficult. Pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP), a marker specific for bone degradation found in gingival crevicular fluid (GCF), has been associated with both bone and attachment loss in periodontitis and may be useful for predicting disease activity. The aim of this cross-sectional study was to examine the relationship between ICTP levels and subgingival species around implants and teeth from 20 partially and 2 fully edentulous patients. GCF and plaque samples were collected from the mesiobuccal site of each implant and tooth. Radioimmunoassay techniques were utilized to determine GCF ICTP levels. Plaque samples were analyzed utilizing checkerboard DNA-DNA hybridization. Traditional clinical parameters were assessed. Seventy-one implants and 370 teeth from 22 subjects were examined. ICTP levels and subgingival plaque composition were not significantly different between implants and teeth. Implant sites colonized by Prevotella intermedia, Capnocytophaga gingivalis, Fusobacterium nucleatum ss vincentii, and Streptococcus gordonii exhibited odds ratios of 12.4, 9.3, 8.1, and 6.7, respectively of detecting ICTP. These results suggest a relationship between elevated ICTP levels at implant sites and some species associated with disease progression. Longitudinal studies are necessary to determine whether elevated ICTP levels may predict the development of peri-implant bone loss.

Adult↗
PubMed1998

Relationship between C-telopeptide pyridinoline cross-links (ICTP) and putative periodontal pathogens in periodontitis.

Crevicular fluid pyridinoline cross-linked carboxyterminal telopeptide of type I collagen (ICTP) is predictive for future alveolar bone loss in experimental periodontitis in dogs. The present study sought to relate ICTP to a panel of subgingival species in subjects exhibiting various clinical presentations such as health (n=7), gingivitis (n=8) and periodontitis (n=21). 28 subgingival plaque and GCF samples were taken from mesiobuccal sites in each of 36 subjects. The presence and levels of 40 subgingival taxa were determined in plaque samples using whole genomic DNA probes and checkerboard DNA-DNA hybridization. GCF ICTP levels were quantified using radioimmunoassay (RIA). Clinical assessments made at the same sites included: BOP, gingival redness, plaque, pocket depth, and attachment level. Differences among ICTP levels in the 3 subject groups were sought using the Kruskal-Wallis test. Relationships between ICTP levels and clinical parameters as well as subgingival species were determined by regression analysis. The results demonstrated significant differences among disease categories for GCF ICTP levels for healthy (1.1+0.6 pg/site (mean+/-SEM)) gingivitis (14.8+/-6.6 pg/site) and periodontitis subjects (30.3+5.7 pg/site) (p= 0.0017). ICTP levels related modestly to several clinical parameters. Regression analysis indicated that ICTP levels correlated strongly with mean subject levels of several periodontal pathogens including B. forsythus, P. gingivalis, P. intermedia, P. nigrescens and T. denticola (p<0.01). The data indicate that there is a positive relationship between the putative bone resorptive marker ICTP and periodontal pathogens.

Adult↗