Evaluation of periodontal status and cytokine response in children with familial Mediterranean fever or systemic juvenile idiopathic arthritis.

OBJECTIVES: Familial Mediterranean fever (FMF) and systemic juvenile idiopathic arthritis (sJIA) are chronic inflammatory diseases and anti-inflammatory agents are used in their treatment. This study evaluates the periodontal status and cytokine response in pediatric patients with FMF or sJIA. MATERIALS AND METHODS: Forty-eight FMF/sJIA patients were under treatment/control and in attack-free period; 20 systemically healthy children participated in the study. FMF/sJIA patients were divided into two subgroups based on the treatment they received: receiving anti-IL-1 therapy (anti-IL-1 ( +)) and not receiving anti-IL-1 therapy (anti-IL-1 ( -)). The clinical periodontal indices were recorded. Gingival crevicular fluid (GCF) and serum samples were collected. Cytokine levels (IL-1ß, IL-1α, TNF-α, IL-6, IL-8, IL-10, IL-17, IL-33) in GCF and serum were measured using ELISA kits. RESULTS: There was no significant difference between the groups in terms of GCF IL-1ß and IL-1α levels although, BoP and GI were significantly lower in the anti-IL-1 ( +) group compared to the control group. GCF IL-10 level was higher in the anti-IL-1 ( -) group than in the control group; GCF IL-8 levels were lower in both FMF/sJIA subgroups versus controls. There was no significant difference between serum cytokine levels of FMF/sJIA subgroups. CONCLUSIONS: Considering the significant decrease in GI, BoP, and GCF IL-8 levels in the anti-IL-1 ( +) group, it can be concluded that anti-IL-1 medications may suppress periodontal inflammation clinically and immunologically. CLINICAL RELEVANCE: Anti-IL agents are not currently used in periodontal therapy. However, this study demonstrated the positive effect of anti-IL-1 medications on periodontal inflammation in pediatric patients with FMF or sJIA.

Sex-specific analysis in Behçet's disease reveals higher genetic risk in male patients.

OBJECTIVES: Behçet's disease tends to be more severe in men than women. This study was undertaken to investigate sex-specific genetic effects in Behçet's disease. METHODS: A total of 1762 male and 1216 female patients with Behçet's disease from six diverse populations were studied, with the majority of patients of Turkish origin. Genotyping was performed using an Infinium ImmunoArray-24 BeadChip, or extracted from available genotyping data. Following imputation and extensive quality control measures, genome-wide association analysis was performed comparing male to female patients in the Turkish cohort, followed by a meta-analysis of significant results in all six populations. In addition, a weighted genetic risk score for Behçet's disease was calculated and compared between male and female patients. RESULTS: Genetic association analysis comparing male to female patients with Behçet's disease from Turkey revealed an association with male sex in HLA-B/MICA within the HLA region with a GWAS level of significance (rs2848712, OR = 1.46, P = 1.22 × 10-8). Meta-analysis of the effect in rs2848712 across six populations confirmed these results. Genetic risk score for Behçet's disease was significantly higher in male compared to female patients from Turkey. Higher genetic risk for Behçet's disease was observed in male patients in HLA-B/MICA (rs116799036, OR = 1.45, P = 1.95 × 10-8), HLA-C (rs12525170, OR = 1.46, P = 5.66 × 10-7), and KLRC4 (rs2617170, OR = 1.20, P = 0.019). In contrast, IFNGR1 (rs4896243, OR = 0.86, P = 0.011) was shown to confer higher genetic risk in female patients. CONCLUSIONS: Male patients with Behçet's disease are characterized by higher genetic risk compared to female patients. This genetic difference, primarily derived from our Turkish cohort, is largely explained by risk within the HLA region. These data suggest that genetic factors might contribute to differences in disease presentation between men and women with Behçet's disease.

In vivo efficacy of low-level laser therapy on bone regeneration.

PURPOSE: In clinical use of low-level laser therapy for bone regeneration (LLLT), application protocol (dose, duration, and repetitions) has not been established. This study aimed to depict a reliable dosage of LLLT by evaluating the efficacy of different dosing of LLLT (diode) on the healing of rabbit cranial defects. METHODS: Critical size defects were prepared in calvarias of 26 New Zealand White Rabbits in such each animal containing both test and control groups. Test groups were irradiated with 4 Joule/cm2 (j/cm2), 6 j/cm2, and 8 j/cm2. The rabbits were subjected to six times of laser treatments in 10 days. At the end of the second week, 5 rabbits were sacrificed for histopathological and immunohistochemical analyses. At the 4th and 8th weeks, 20 rabbits (10 each) were sacrificed for micro-CT and histopathological analyses. RESULTS: Micro-CT evaluation revealed improved new bone formation in all test groups compared to the control group. 6 j/cm2 group demonstrated the highest bone formation. The highest bone morphogenic protein -2 levels were found in the 4 j/cm2 group. Osteocalcin expression was significantly higher in 4 j/cm2 group. CONCLUSIONS: Our findings indicate that LLLT have a positive effect on new bone formation. The high efficacy of doses of 4 j/cm2 and 6 j/cm2 is promising to promote early bone healing.

Evaluation of GCF IL-17, IL-10, TWEAK, and sclerostin levels after scaling and root planing and adjunctive use of diode laser application in patients with periodontitis.

BACKGROUND: The aim of the present study was to evaluate the clinical efficacy of the diode laser as an adjunct to scaling and root planing (SRP) and also determine the biochemical profile by evaluating the gingival crevicular fluid (GCF) levels of interleukin (IL)-17, IL-10, tumor necrosis factor-related weak inducer of apoptosis (TWEAK), and sclerostin. METHODS: A total of 40 systemically healthy, patients with Stage III periodontitis were included in this randomized controlled study. Participants were randomly divided into two groups as SRP + diode laser (L) (0.80W power, 940 nm wavelength and 0.80J/s energy level) and only SRP group. Recording of periodontal parameters and collecting GCF samples were performed at baseline, first and 3rd months. Biomarker levels in GCF were measured with ELISA RESULTS: At baseline, no significant difference was detected between groups in terms of both clinical and biochemical parameters. All biochemical parameters (except for IL-10 in control group), presented a statistically significant difference for 3 months study period in both groups. When laser and control groups were compared, significant differences were not observed, except the lower GCF IL-17 levels (P = 0.025), bleeding on probing (P = 0.028), and clinical attachment level (CAL) (P = 0.0002) values in laser group at third, first, and third months, respectively. Statistically significant correlations were also noted between biochemical parameters and clinical parameters. CONCLUSIONS: The GCF IL-17, TWEAK, and sclerostin levels may be useful for monitoring response to SRP+L therapy. However, long-term studies on higher populations are needed to evaluate the effectiveness of adjunctive use of diode laser application to SRP.

Epigenetic adaptations of the masticatory mucosa to periodontal inflammation.

BACKGROUND: In mucosal barrier interfaces, flexible responses of gene expression to long-term environmental changes allow adaptation and fine-tuning for the balance of host defense and uncontrolled not-resolving inflammation. Epigenetic modifications of the chromatin confer plasticity to the genetic information and give insight into how tissues use the genetic information to adapt to environmental factors. The oral mucosa is particularly exposed to environmental stressors such as a variable microbiota. Likewise, persistent oral inflammation is the most important intrinsic risk factor for the oral inflammatory disease periodontitis and has strong potential to alter DNA-methylation patterns. The aim of the current study was to identify epigenetic changes of the oral masticatory mucosa in response to long-term inflammation that resulted in periodontitis. METHODS AND RESULTS: Genome-wide CpG methylation of both inflamed and clinically uninflamed solid gingival tissue biopsies of 60 periodontitis cases was analyzed using the Infinium MethylationEPIC BeadChip. We validated and performed cell-type deconvolution for infiltrated immune cells using the EpiDish algorithm. Effect sizes of DMPs in gingival epithelial and fibroblast cells were estimated and adjusted for confounding factors using our recently developed "intercept-method". In the current EWAS, we identified various genes that showed significantly different methylation between periodontitis-inflamed and uninflamed oral mucosa in periodontitis patients. The strongest differences were observed for genes with roles in wound healing (ROBO2, PTP4A3), cell adhesion (LPXN) and innate immune response (CCL26, DNAJC1, BPI). Enrichment analyses implied a role of epigenetic changes for vesicle trafficking gene sets. CONCLUSIONS: Our results imply specific adaptations of the oral mucosa to a persistent inflammatory environment that involve wound repair, barrier integrity, and innate immune defense.

The effect of gamma and microwave radiation sterilization on periodontological grafts for microbiological evaluation.

Periodontological grafts are materials used in dentistry to regenerate lost gingival soft tissues or bone parts. In the case of direct contact with blood, the possibility of disease transmission from the source to the patient is high. This source can be an animal or a human. Therefore, the sterilization of grafts before implanting to the patient is of significant importance. The purpose of this study was to evaluate gamma radiation and microwave sterilization processes from microbiological and sterility perspectives and to compare the effectiveness of these two sterilization methods. Grafts were irradiated with 2, 4, 5, 10, 25 and 50 kGy doses of gamma radiation. Another group of same materials was irradiated by microwave for 1, 2, 3 and 4 min at 24,500 MHz and 900 W. Gamma radiation and microwave sterilization methods were evaluated as successful at minimum doses as 5 kGy and 3 min, respectively. Both gamma and microwave sterilization successfu lly sterilized periodontological grafts coded as PBG1, HBG1, HL1, PDG1, MBG3, MDG2 and PDG3. Moreover, microwave sterilization can be used as an alternative novel method to gamma radiation sterilization.

Genetic Association of a Gain-of-Function IFNGR1 Polymorphism and the Intergenic Region LNCAROD/DKK1 With Behçet's Disease.

OBJECTIVE: Behçet's disease is a complex systemic inflammatory vasculitis of incompletely understood etiology. This study was undertaken to investigate genetic associations with Behçet's disease in a diverse multiethnic population. METHODS: A total of 9,444 patients and controls from 7 different populations were included in this study. Genotyping was performed using an Infinium ImmunoArray-24 v.1.0 or v.2.0 BeadChip. Analysis of expression data from stimulated monocytes, and epigenetic and chromatin interaction analyses were performed. RESULTS: We identified 2 novel genetic susceptibility loci for Behçet's disease, including a risk locus in IFNGR1 (rs4896243) (odds ratio [OR] 1.25; P = 2.42 × 10-9 ) and within the intergenic region LNCAROD/DKK1 (rs1660760) (OR 0.78; P = 2.75 × 10-8 ). The risk variants in IFNGR1 significantly increased IFNGR1 messenger RNA expression in lipopolysaccharide-stimulated monocytes. In addition, our results replicated the association (P < 5 × 10-8 ) of 6 previously identified susceptibility loci in Behçet's disease: IL10, IL23R, IL12A-AS1, CCR3, ADO, and LACC1, reinforcing the notion that these loci are strong genetic factors in Behçet's disease shared across ancestries. We also identified >30 genetic susceptibility loci with a suggestive level of association (P < 5 × 10-5 ), which will require replication. Finally, functional annotation of genetic susceptibility loci in Behçet's disease revealed their possible regulatory roles and suggested potential causal genes and molecular mechanisms that could be further investigated. CONCLUSION: We performed the largest genetic association study in Behçet's disease to date. Our findings reveal novel putative functional variants associated with the disease and replicate and extend the genetic associations in other loci across multiple ancestries.

Dual delivery of platelet-derived growth factor and bone morphogenetic factor-6 on titanium surface to enhance the early period of implant osseointegration.

OBJECTIVE: To test the surface properties and in vitro effects of a new sequential release system on MC3T3-E1 cells for improved osseointegration. BACKGROUND: BMP6-loaded anodized titanium coated with PDGF containing silk fibroin (SF) may improve osseointegration. METHODS: Titanium surfaces were electrochemically anodized, and SF layer was covered via electrospinning. Five experimental groups (unanodized Ti (Ti), anodized Ti (AnTi), anodized + BMP6-loaded Ti (AnTi-BMP6), anodized + BMP6 loaded + silk fibroin-coated Ti (AnTi-BMP6-SF), and anodized + BMP6-loaded + silk fibroin with PDGF-coated Ti (AnTi-BMP6-PDGF-SF)) were tested. After SEM characterization, contact angle analysis, and FTIR analysis, the amount of released PDGF and BMP6 was detected using ELISA. Cell proliferation (XTT), mineralization, and gene expression (RUNX2 and ALPL) were also evaluated. RESULTS: After successful anodization and loading of PDGF and BMP6, contact angle measurements showed hydrophobicity for TiO2 and hydrophilicity for protein-adsorbed surfaces. In FTIR, protein-containing surfaces exhibited amide-I, amide-II, and amide-III bands at 1600 cm-1 -1700 cm-1 , 1520 cm-1 -1540 cm-1 , and 1220 cm-1 -1300 cm-1 spectrum levels with a significant peak in BMP6- and/or SF-loaded groups at 1100 cm-1 . PDGF release and BMP6 release were delayed, and relatively slower release was detected in SF-coated surfaces. Higher MC3T3-E1 proliferation and mineralization and lower gene expression of RUNX2 and ALPL were detected in AnTi-BMP6-PDGF-SF toward day 28. CONCLUSION: The new system revealed a high potential for an improved early osseointegration period by means of a better factor release curve and contribution to the osteoblastic cell proliferation, mineralization, and associated gene expression.

The tendency of reduced periodontal destruction in acromegalic patients showing similar inflammatory status with periodontitis patients.

PURPOSE: Evaluate periodontal status of acromegalics through clinical and biochemical variables. METHODS: Demographics, hormone and metabolic variables, periodontal variables, gingival crevicular fluid (GCF) volume, and content data were collected from 30 patients with acromegaly, 30 patients with periodontitis, and 20 healthy subjects and comparatively analyzed. RESULTS: GH differences between acromegaly (2.56 ± 4.86) and periodontitis (0.53 ± 0.95) (p < 0.001) were statistically significant. IGF-1 was lowest at periodontitis (113.31 ± 45.01) and lower (152.11 ± 45.56) at healthy group compared with acromegalics (220.38 ± 167.62) (p < 0.05). GH and IGF-1 had positive correlation (p < 0.05). IGF-1 and CAL had negative (p < 0.01) correlation except healthy group that showed the same correlation at the opposite direction (p < 0.05). Besides similar plaque and gingival indices with periodontitis, acromegalics showed relatively less CAL and GCF volume but except CAL, all their periodontal variables were higher than healthy subjects. GCF GH and prolactin showed higher values in acromegalics while healthy subjects showed relatively high interleukin-1, -10 and carboxyterminal telopeptide of type I collagen compared with others. CONCLUSION: Acromegalics have a tendency of slowed periodontal destruction with an influence of GH and IGF-1 to the inflammation- and collage metabolism-related mechanisms rather than bone-associated ones. However, this information must be confirmed with further studies exploring the mechanisms possibly bonded to others.

Evaluation of gingival crevicular fluid and peri-implant crevicular fluid levels of sclerostin, TWEAK, RANKL and OPG.

BACKGROUND: The combination of local and systemic factors play role in the pathogenesis of periodontal and peri-implant diseases. Host-derived enzymes, cytokines and other proinflammatory mediators play an integral role in this destruction. The aim of this study is to evaluate gingival crevicular fluid (GCF) and peri-implant crevicular (PICF) fluid levels of sclerostin, TNF-related weak inducer of apoptosis (TWEAK), receptor activator of nuclear factor kappa-beta ligand (RANKL) and osteoprotegerin OPG in periodontal and peri-implant tissues in disease and health conditions and also to assess the potential for use as biomarkers. MATERIALS AND METHODS: The study population was consisted of 50 women and 41 men, in the total of 91 individuals, with a mean age of 51.84 ±â€¯14.05. Periodontitis (n = 22), periodontal health (n = 17), peri-implantitis (n = 27) and peri-implant health (n = 25) groups were established according to clinical and radiographic examination results of 39 teeth and 52 implants restored with fixed prosthetic restorations. In all groups, periodontal and peri-implant parameters (probing depth, gingival recession, gingival bleeding time index, gingival index, and plaque index) were recorded and GCF and PICF samples were also collected. Sclerostin, TWEAK, RANKL and OPG levels in GCF and PICF were measured with ELISA tests. RESULTS: Peri-implantitis group presented significantly higher levels of Sclerostin (p = 0.002), TWEAK(p < 0.0001), RANKL(p < 0.0001), and OPG (p = 0.037) compared to peri-implant health group. Similarly, significantly higher levels of TWEAK (p = 0.001), RANKL(p < 0.0001), and OPG(p = 0.025) were detected in periodontitis group when compared to periodontal health group. Statistically significant correlations were also noted between biochemical parameters and clinical parameters. CONCLUSION: Findings of this study evaluating four different bone metabolism related proteins at the same time, suggests levels of sclerostin may be a biomarker for peri-implant disease presenting significantly higher levels in the peri-implantitis group than in the peri-implant health group. Moreover, levels of TWEAK can be a good indicator for both periodontal and peri-implant disease, due to the correlations with periodontal clinical parameters and the higher levels of TWEAK in diseased sites compared to the healthy sites for both dental implants and teeth.

Evaluation of gingival crevicular fluid and peri-implant sulcus fluid levels of periostin: A preliminary report.

BACKGROUND: Periostin is a protein present in alveolar bone and periodontal ligament whose function is related to response to external forces. The aims of this study are to detect levels of periostin in peri-implant sulcular fluid (PISF) and gingival crevicular fluid (GCF) and to evaluate the relationship between periostin, pyridinoline cross-linked carboxyterminal telopeptide of Type I collagen (ICTP), and C-terminal cross-linked telopeptide of Type I collagen (CTX) levels and clinical inflammatory symptoms and duration of functional loading. METHODS: The study population comprised nine women and four men with mean age 43.23 ± 12.48. Twenty "bone-level designed" dental implants (DIs) placed in molar or premolar sites, without any signs of peri-implant bone loss and with a restoration in function for at least 12 months, were included in the study with 20 contralateral natural teeth (NT) as controls. Clinical parameters and restoration dates of the implants were recorded. PISF, GCF, ICTP, CTX, and periostin levels were evaluated using enzyme-linked immunosorbent assay. RESULTS: ICTP, CTX, and periostin levels were similar between DI and NT groups. There were no statistically significant differences between PISF and GCF values. When implants were grouped as healthy (gingival index [GI] = 0) and inflamed (GI ≥0), ICTP levels and PISF volume were lower in healthy implants compared with the inflamed group. Both periostin and CTX levels were negatively correlated with functioning time, suggesting less bone remodeling around DIs at later stages of functioning. CONCLUSION: Findings of this study suggest collagen breakdown products may be used as markers to evaluate peri-implant metabolism.

ESR investigations of gamma irradiated medical devices.

Guided tissue regeneration (GTR) and guided bone regeneration (GBR) biomaterials have been employed in recent years for periodontal procedures. In the present study, widely used dental GTR/GBR biomaterials (grafts: G1, G2, G3 and membranes: M1, M2, M3, M4) were exposed to gamma irradiation at an absorbed dose range of 0-50kGy and the radiolytic intermediates that have been created in the samples upon irradiation were characterized in detail by Electron Spin Resonance (ESR) spectroscopy. We aimed to standardize the measurement conditions for practical applications of gamma radiation sterilization of GTR/GBR biomaterials. We investigated the characteristic features of free radicals in gamma irradiated GTR/GBR biomaterials and examined the stability of the induced radicals at room temperature and accelerated stability conditions with ESR spectroscopy including dose-response curves, microwave power studies, dosimetric features of the biomaterials, variations of the peak heights with temperature, and long term stabilities of the radical species. Long-term stability studies have shown that G1 is quite stable even in accelerated storage conditions. The signal intensities of graft-type GTR/GBR biomaterials stored in normal and stability conditions have decreased very rapidly even only a few days after gamma irradiation sterilization. Thus, those samples indicating relatively low stability features can be very good candidates for the radiosterilization process. The beta-tricalcium phosphate and PLGA containing G1 and M1 respectively have found to be the most gamma stable bone substitute biomaterials and be safely sterilized by gamma radiation. ESR spectroscopy is an appropriate technique in giving important detailed spectroscopic findings in the gamma radiation sterilization studies of GTR/GBR biomaterials.

Sequential IGF-1 and BMP-6 releasing chitosan/alginate/PLGA hybrid scaffolds for periodontal regeneration.

The goal of periodontal tissue engineering is to repair or regenerate the destructed or lost periodontium by improving functions of cells in the remaining tissue. For continuty of cell growth process, two group of growth factors, i.e. competence factors and progression factors, are needed to act together. However, the short biological half-life of these factors limits their effects on cells and their clinical efficacy. The purpose of this study is to develop different microparticles-loaded chitosan carriers/scaffolds for controlled and sequential delivery of a competence factor, insulin-like growth factor (IGF-1), and progression factor, bone morphogenetic factor-6 (BMP-6). Alginate and poly (lactic-co-glycolic acid) (PLGA) microparticles provided release of IGF-1 and BMP-6 for early short period and for long period, respectively. The cell culture studies showed that, chitosan/alginate/PLGA hybrid scaffolds induced proliferation and osteoblastic differentiation of cementoblasts when compared with IGF-1 and BMP-6 free chitosan scaffold.

A genome-wide association study identifies nucleotide variants at SIGLEC5 and DEFA1A3 as risk loci for periodontitis.

Periodontitis is one of the most common inflammatory diseases, with a prevalence of 11% worldwide for the severe forms and an estimated heritability of 50%. The disease is characterized by destruction of the alveolar bone due to an aberrant host inflammatory response to a dysbiotic oral microbiome. Previous genome-wide association studies (GWAS) have reported several suggestive susceptibility loci. Here, we conducted a GWAS using a German and Dutch case-control sample of aggressive periodontitis (AgP, 896 cases, 7,104 controls), a rare but highly severe and early-onset form of periodontitis, validated the associations in a German sample of severe forms of the more moderate phenotype chronic periodontitis (CP) (993 cases, 1,419 controls). Positive findings were replicated in a Turkish sample of AgP (223 cases, 564 controls). A locus at SIGLEC5 (sialic acid binding Ig-like lectin 5) and a chromosomal region downstream of the DEFA1A3 locus (defensin alpha 1-3) showed association with both disease phenotypes and were associated with periodontitis at a genome-wide significance level in the pooled samples, with P = 1.09E-08 (rs4284742,-G; OR = 1.34, 95% CI = 1.21-1.48) and P = 5.48E-10 (rs2738058,-T; OR = 1.28, 95% CI = 1.18-1.38), respectively. SIGLEC5 is expressed in various myeloid immune cells and classified as an inhibitory receptor with the potential to mediate tyrosine phosphatases SHP-1/-2 dependent signaling. Alpha defensins are antimicrobial peptides with expression in neutrophils and mucosal surfaces and a role in phagocyte-mediated host defense. This study identifies the first shared genetic risk loci of AgP and CP with genome-wide significance and highlights the role of innate and adaptive immunity in the etiology of periodontitis.

Genetic evidence for PLASMINOGEN as a shared genetic risk factor of coronary artery disease and periodontitis.

BACKGROUND: Genetic studies demonstrated the presence of risk alleles in the genes ANRIL and CAMTA1/VAMP3 that are shared between coronary artery disease (CAD) and periodontitis. We aimed to identify further shared genetic risk factors to better understand conjoint disease mechanisms. METHODS AND RESULTS: In-depth genotyping of 46 published CAD risk loci of genome-wide significance in the worldwide largest case-control sample of the severe early-onset phenotype aggressive periodontitis (AgP) with the Illumina Immunochip (600 German AgP cases, 1448 controls) and the Affymetrix 500K array set (283 German AgP cases and 972 controls) highlighted ANRIL as the major risk gene and revealed further associations with AgP for the gene PLASMINOGEN (PLG; rs4252120: P=5.9×10(-5); odds ratio, 1.27; 95% confidence interval, 1.3-1.4 [adjusted for smoking and sex]; 818 cases; 5309 controls). Subsequent combined analyses of several genome-wide data sets of CAD and AgP suggested TGFBRAP1 to be associated with AgP (rs2679895: P=0.0016; odds ratio, 1.27 [95% confidence interval, 1.1-1.5]; 703 cases; 2.143 controls) and CAD (P=0.0003; odds ratio, 0.84 [95% confidence interval, 0.8-0.9]; n=4117 cases; 5824 controls). The study further provides evidence that in addition to PLG, the currently known shared susceptibility loci of CAD and periodontitis, ANRIL and CAMTA1/VAMP3, are subjected to transforming growth factor-ß regulation. CONCLUSIONS: PLG is the third replicated shared genetic risk factor of atherosclerosis and periodontitis. All known shared risk genes of CAD and periodontitis are members of transforming growth factor-ß signaling.

Validation of reported genetic risk factors for periodontitis in a large-scale replication study.

AIM: Many studies investigated the role of genetic variants in periodontitis, but few were established as risk factors. We aimed to validate the associations of recent candidate genes in aggressive periodontitis (AgP). MATERIAL AND METHODS: We analysed 23 genes in 600 German AgP patients and 1441 controls on the Illumina custom genotyping array Immunochip. We tested a suggestive association in a Dutch and German/Austrian AgP case-control sample, and a German chronic periodontitis (CP) case-control sample using Sequenom iPlex assays. We additionally tested the common known risk variant rs1333048 of the gene ANRIL for its association in a Turkish and Italian population. RESULTS: None of the analysed genes gave statistical evidence for association. Upon covariate adjustment for smoking and gender, in the pooled German-Austrian AgP sample, IL10 SNP rs6667202 was associated with p = 0.016, OR = 0.77 (95% CI = 0.6-0.95), and in the Dutch AgP sample, adjacent IL10 SNP rs61815643 was associated with p = 0.0009, OR = 2.31 (95% CI = 1.4-3.8). At rs61815643, binding of the transcription factor PPARG was predicted. ANRIL rs1333048 was associated in the Turkish sample (pallelic = 0.026, OR = 1.67 [95% CI = 1.11-2.60]). CONCLUSIONS: Previous candidate genes carry no susceptibility factors for AgP. Association of IL-10 rs61815643 with AgP is suggested. ANRIL is associated with periodontitis across different populations.

Platelet-rich plasma-loaded chitosan scaffolds: preparation and growth factor release kinetics.

The aim of this study is to compare the effects of different platelet-rich plasma (PRP) preparation methods on platelet activity and to investigate the growth factor (GF) release kinetics from PRP-loaded chitosan scaffolds for tissue engineering applications. Flow cytometry analysis showed that centrifugation processes used for PRP preparation did not cause significant effect on platelet activation levels by means of markers investigated. Two different methods were used to prepare PRP-loaded chitosan scaffolds: (i) PRP was added to chitosan gel before freeze-drying to prepare scaffolds called as "GEL" and (ii) PRP was embedded to freeze-dried chitosan scaffolds to prepare scaffolds called as "SPONGE." In addition, nonactivated PRP and PRP activated with type-I collagen were used as control groups. Scanning electron microscopy images demonstrated that, in GEL group, there is no deterioration on the scaffolds porous, 3D, and interconnected structure. GF release kinetics was determined by enzyme-linked immunosorbent assay for platelet-derived GF-BB, transforming GF-ß1, and insulin-like GF-1. A sustained release of GFs was achieved in GEL group while a sharp burst release was observed for all the GFs from the SPONGE groups. Moreover, platelet-derived GF-BB, insulin-like GF-1, and transforming GF-ß1 releases were prolonged to 20 days in GEL groups, and the biological activities of all GFs released from GEL and SPONGE scaffolds were preserved. This study demonstrated that chitosan scaffold that was called GEL could be an appropriate carrier for PRP applications by providing sustained release of GFs.

Periodontal ligament cell behavior on different titanium surfaces.

AIM: The purpose of this study was to investigate proliferation, morphology, mineralization and mRNA expressions of mineralized tissue associated proteins of PDL cells on smooth (S), sandblasted small-grit (SSG), sandblasted large-grit (SLG) and sodium titanate (NaTi) coated titanium alloys, in vitro. METHODS AND MATERIALS: PDL cells were cultured with DMEM media containing 10% FBS on the S, SSG, SLG and NaTi titanium surfaces. PDL cell proliferation, mineralization and immunohistochemistry experiments for Bone Sialoprotein (BSP) were performed. The morphology of the PDL cells was examined using confocal and scanning electron microscopy (SEM). Gene expression profiles of cells were evaluated using a quantitative-polymerase chain reaction (Q-PCR) for type I collagen (COL I), Osteocalcin (OCN), osteopontin (OPN) and Runt-related transcription factor-2 (Runx2) on days 7 and 14. RESULTS: Proliferation results on days 6 and 10 were similar in groups, while those of day 13 revealed a decrease in the NaTi group when compared to the S group. NaTi surface induced BSP mRNA expression which was correlated with mineralization tests and BSP immunostaining results. Increased Runx2 mRNA expression was also noted in the NaTi surface when compared to other surfaces. CONCLUSIONS: This study considers the NaTi surface as a potential alternative to SSG and SLG surfaces. This surface might provide a promising environment for PDL ligament-anchored implants.

Bone morphogenetic protein-7 enhances cementoblast function in vitro.

BACKGROUND: Bone morphogenetic protein (BMP)-7 is a potent bone-inducing factor and was shown to promote periodontal regeneration in vivo and in vitro; however, to our knowledge, the specific effect of BMP-7 on cementoblasts has not been defined. We aimed to investigate the effects of BMP-7 on cementoblasts, which are cells responsible for tooth root-cementum formation. We hypothesized that BMP-7 would regulate mineralized tissue-associated genes in cementoblasts and influence the expression profile of genes associated with cementoblast extracellular matrix (ECM) and cell adhesion molecules (CAMs). METHODS: A murine immortalized cementoblast cell line (OCCM.30) was cultured with and without 50 ng/ml BMP-7. After 72 hours, total RNA was isolated, and mRNA levels for bone/cementum markers, including bone sialoprotein (BSP), osteocalcin (OCN), osteopontin (OPN), and runt-related transcription factor-2 (Runx2), were investigated by real-time quantitative reverse transcription-polymerase chain reaction (Q-PCR). In vitro mineral nodule formation was assayed on day 8 using von Kossa staining. A pathway-specific gene-expression array was used to determine BMP-7-responsive ECM and CAM genes in cementoblasts. RESULTS: Mineralized tissue markers were strongly regulated by BMP-7, with an almost three-fold increase in BSP and OCN transcripts and significant increases in OPN and Runx2 mRNA expressions. BMP-7 treatment markedly stimulated cementoblast-mediated biomineralization in vitro compared to untreated cells at day 8. BMP-7 treatment altered the OCCM.30 expression profile for ECM and CAM functional gene groups. BMP-7 tended to increase the expression of collagens and matrix metalloproteinases (MMPs), mildly decreased tissue inhibitors of MMPs (TIMPs), and had mixed regulatory effects on integrins. Using Q-PCR, selected array results were confirmed, including a significant BMP-7-induced increase in MMP-3 and a decrease in TIMP-2 mRNA expression. CONCLUSION: These results support the promising applications of BMP-7 in therapies aimed at regenerating periodontal tissues lost as a consequence of disease.