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Efficacy of chemical approaches for implant surface decontamination in conjunction with sub‐marginal instrumentation, in the non‐surgical treatment of peri‐implantitis. A systematic review. J Clin Periodontol 2022. [DOI: 10.1111/jcpe.13749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 10/21/2022] [Accepted: 11/04/2022] [Indexed: 11/16/2022]
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Coordinated activation of TGF-β and BMP pathways promotes autophagy and limits liver injury after acetaminophen intoxication. Sci Signal 2022; 15:eabn4395. [PMID: 35763560 DOI: 10.1126/scisignal.abn4395] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Ligands of the transforming growth factor-β (TGF-β) superfamily, including TGF-βs, activins, and bone morphogenetic proteins (BMPs), have been implicated in hepatic development, homeostasis, and pathophysiology. We explored the mechanisms by which hepatocytes decode and integrate injury-induced signaling from TGF-βs and activins (TGF-β/Activin) and BMPs. We mapped the spatiotemporal patterns of pathway activation during liver injury induced by acetaminophen (APAP) in dual reporter mice carrying a fluorescent reporter of TGF-β/Activin signaling and a fluorescent reporter of BMP signaling. APAP intoxication induced the expression of both reporters in a zone of cells near areas of tissue damage, which showed an increase in autophagy and demarcated the borders between healthy and injured tissues. Inhibition of TGF-β superfamily signaling by overexpressing the inhibitor Smad7 exacerbated acute liver histopathology but eventually accelerated tissue recovery. Transcriptomic analysis identified autophagy as a process stimulated by TGF-β1 and BMP4 in hepatocytes, with Trp53inp2, which encodes a rate-limiting factor for autophagy initiation, as the most highly induced autophagy-related gene. Collectively, these findings illustrate the functional interconnectivity of the TGF-β superfamily signaling system, implicate the coordinated activation of TGF-β/Activin and BMP pathways in balancing tissue reparatory and regenerative processes upon APAP-induced hepatotoxicity, and highlight opportunities and potential risks associated with targeting this signaling system for treating hepatic diseases.
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TFEB signaling attenuates NLRP3-driven inflammatory responses in severe asthma. Allergy 2022; 77:2131-2146. [PMID: 35038351 DOI: 10.1111/all.15221] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 12/20/2021] [Accepted: 12/26/2021] [Indexed: 12/11/2022]
Abstract
BACKGROUND NLRP3-driven inflammatory responses by circulating and lung-resident monocytes are critical drivers of asthma pathogenesis. Autophagy restrains NLRP3-induced monocyte activation in asthma models. Yet, the effects of autophagy and its master regulator, transcription factor EB (TFEB), on monocyte responses in human asthma remain unexplored. Here, we investigated whether activation of autophagy and TFEB signaling suppress inflammatory monocyte responses in asthmatic individuals. METHODS Peripheral blood CD14+ monocytes from asthmatic patients (n = 83) and healthy controls (n = 46) were stimulated with LPS/ATP to induce NLRP3 activation with or without the autophagy inducer, rapamycin. ASC specks, caspase-1 activation, IL-1β and IL-18 levels, mitochondrial function, ROS release, and mTORC1 signaling were examined. Autophagy was evaluated by LC3 puncta formation, p62/SQSTM1 degradation and TFEB activation. In a severe asthma (SA) model, we investigated the role of NLRP3 signaling using Nlrp3-/- mice and/or MCC950 administration, and the effects of TFEB activation using myeloid-specific TFEB-overexpressing mice or administration of the TFEB activator, trehalose. RESULTS We observed increased NLRP3 inflammasome activation, concomitant with impaired autophagy in circulating monocytes that correlated with asthma severity. SA patients also exhibited mitochondrial dysfunction and ROS accumulation. Autophagy failed to inhibit NLRP3-driven monocyte responses, due to defective TFEB activation and excessive mTORC1 signaling. NLRP3 blockade restrained inflammatory cytokine release and linked airway disease. TFEB activation restored impaired autophagy, attenuated NLRP3-driven pulmonary inflammation, and ameliorated SA phenotype. CONCLUSIONS Our studies uncover a crucial role for TFEB-mediated reprogramming of monocyte inflammatory responses, raising the prospect that this pathway can be therapeutically harnessed for the management of SA.
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Impact of salivary contamination during placement of implants with simultaneous bony augmentation in iliac bone in sheep. Br J Oral Maxillofac Surg 2019; 57:1131-1136. [PMID: 31672257 DOI: 10.1016/j.bjoms.2019.10.302] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Accepted: 10/10/2019] [Indexed: 11/19/2022]
Abstract
Our aim was to investigate the possible impact of contamination with saliva on osseointegration during placement of implants with simultaneous bone augmentation. Six hemispheric shape bone defects (8mm in diameter×4mm deep) were prepared in each iliac bone of six sheep. A dental implant (2.9mm in diameter×10mm long) was placed in the centre of each defect, and then pairs of defects were filled with one of the following bone augmentation materials: autogenous bone, autogenous bone plus bovine bone, or resorbable biphasic ceramic bone substitute. One site in each augmentation group was impregnated with saliva (contaminated group), while the other was not (non-contaminated group). Bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) within implant threads were measured after a healing period of five weeks, both in respect of the implant inserted in the augmented bone and in that inserted in the residual bone. Overall results showed that there was a significant difference between the contaminated and non-contaminated group for BIC in the augmented implant (p=0.028), while there were no significant differences in the implant in residual bone (p=0.722). For BAFO, there were no significant differences between the contaminated and non-contaminated groups among the different augmentation materials. The results showed that contamination with saliva during placement of an implant with simultaneous bone augmentation had a serious deleterious effect on osseointegration of the aspect of the implant within the augmented defect. Contamination with saliva during placement of an implant with simultaneous bone augmentation should therefore be avoided.
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Activation of both transforming growth factor-β and bone morphogenetic protein signalling pathways upon traumatic brain injury restrains pro-inflammatory and boosts tissue reparatory responses of reactive astrocytes and microglia. Brain Commun 2019; 1:fcz028. [PMID: 32954268 PMCID: PMC7425383 DOI: 10.1093/braincomms/fcz028] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 09/24/2019] [Accepted: 10/07/2019] [Indexed: 02/06/2023] Open
Abstract
Various ligands and receptors of the transforming growth factor-β superfamily have been found upregulated following traumatic brain injury; however, the role of this signalling system in brain injury pathophysiology is not fully characterized. To address this, we utilized an acute stab wound brain injury model to demonstrate that hallmarks of transforming growth factor-β superfamily system activation, such as levels of phosphorylated Smads, ligands and target genes for both transforming growth factor-β and bone morphogenetic protein pathways, were upregulated within injured tissues. Using a bone morphogenetic protein-responsive reporter mouse model, we showed that activation of the bone morphogenetic protein signalling pathway involves primarily astrocytes that demarcate the wound area. Insights regarding the potential role of transforming growth factor-β superfamily activation in glia cells within the injured tissues were obtained indirectly by treating purified reactive astrocytes and microglia with bone morphogenetic protein-4 or transforming growth factor-β1 and characterizing changes in their transcriptional profiles. Astrocytes responded to both ligands with considerably overlapping profiles, whereas, microglia responded selectively to transforming growth factor-β1. Novel pathways, crucial for repair of tissue-injury and blood-brain barrier, such as activation of cholesterol biosynthesis and transport, production of axonal guidance and extracellular matrix components were upregulated by transforming growth factor-β1 and/or bone morphogenetic protein-4 in astrocytes. Moreover, both ligands in astrocytes and transforming growth factor-β1 in microglia shifted the phenotype of reactive glia cells towards the anti-inflammatory and tissue reparatory 'A2'-like and 'M0/M2'-like phenotypes, respectively. Increased expression of selected key components of the in vitro modulated pathways and markers of 'A2'-like astrocytes was confirmed within the wound area, suggesting that these processes could also be modulated in situ by the integrated action of transforming growth factor-β and/or bone morphogenetic protein-mediated signalling. Collectively, our study provides a comprehensive comparative analysis of transforming growth factor-β superfamily signalling in reactive astrocytes and microglia and points towards a crucial role of both transforming growth factor-β and bone morphogenetic protein pathways in modulating the inflammatory and brain injury reparatory functions of activated glia cells.
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Gingival thickness assessment at the mandibular incisors with four methods: A cross-sectional study. J Periodontol 2018; 89:1300-1309. [DOI: 10.1002/jper.18-0125] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 04/29/2018] [Accepted: 05/23/2018] [Indexed: 11/08/2022]
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A questionnaire-based study evaluating differences between dental students in Paris (F) and Malmö (SE) regarding diagnosis and treatment decisions of patients with different severity levels of periodontal diseases. EUROPEAN JOURNAL OF DENTAL EDUCATION : OFFICIAL JOURNAL OF THE ASSOCIATION FOR DENTAL EDUCATION IN EUROPE 2018; 22:e392-e399. [PMID: 29316064 DOI: 10.1111/eje.12317] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/27/2017] [Indexed: 06/07/2023]
Abstract
AIM To evaluate differences between last-year dental students in Paris (F) and Malmö (SE) Dental Schools, in regard to their judgement and decision-making within periodontology. MATERIALS AND METHODS Ninety-six last-year dental students from Paris and 45 from Malmö participated in a questionnaire study based on four patient cases: (i) Patient case with generalised alveolar bone loss but no signs of inflammation (Well-maintained), (ii) Patient case with generalised alveolar bone loss and signs of inflammation (Periodontitis), (iii) Patient case with no alveolar bone loss and no signs of inflammation (Healthy) and (iv) Patient case with no alveolar bone loss but with signs of inflammation (Gingivitis). Through multiple-choice questions, the students judged each case as healthy or diseased proposed a diagnosis and treatment measures and estimated the treatment time for each patient. Furthermore, they assessed the prognosis of each patient in case of no treatment. RESULTS Based on a response rate of 83%, the majority in both groups judged all the patients as diseased. More Paris students diagnosed the healthy and the gingivitis case as having periodontitis (P < .05). Furthermore, a larger number of students from Paris recommended several treatment measures and estimated longer treatment times for all the cases (P < .05) and estimated a higher risk for disease progression for the healthy and the gingivitis case (P < .05). CONCLUSIONS Significant variation between students from Paris and Malmö Dental Schools in regard to judgement and decision-making was observed; this may in turn imply that there is still need of improving consistency amongst undergraduate educations in periodontology in Europe.
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In vivo expression of proteases and protease inhibitor, a serpin, by periodontal pathogens at teeth and implants. Mol Oral Microbiol 2018; 33:240-248. [PMID: 29498485 DOI: 10.1111/omi.12220] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/26/2018] [Indexed: 12/16/2022]
Abstract
Porphyromonas gingivalis and Tannerella forsythia secrete proteases, gingipains and KLIKK-proteases. In addition, T. forsythia produces a serpin (miropin) with broad inhibitory spectrum. The aim of this pilot study was to determine the level of expression of miropin and individual proteases in vivo in periodontal and peri-implant health and disease conditions. Biofilm and gingival crevicular fluid (GCF)/ peri-implant sulcular fluid (PISF) samples were taken from healthy tooth and implant sites (n = 10), gingivitis and mucositis sites (n = 12), and periodontitis and peri-implantitis sites (n = 10). Concentration of interleukin-8 (IL-8), IL-1β and IL-10 in GCF was determined by enzyme-linked immunosorbent assay. Loads of P. gingivalis and T. forsythia and the presence of proteases and miropin genes were assessed in biofilm by quantitative PCR, whereas gene expression was estimated by quantitative RT-PCR. The presence of P. gingivalis and T. forsythia, as well as the level of IL-8 and IL-1β, were associated with disease severity in the periodontal and peri-implant tissues. In biofilm samples harboring T. forsythia, genes encoding proteases were found to be present at 72.4% for karilysin and 100% for other KLIKK-protease genes and miropin. At the same time, detectable mRNA expression of individual genes ranged from 20.7% to 58.6% of samples (for forsylisin and miropsin-1, respectively). In comparison with the T. forsythia proteases, miropin and the gingipains were highly expressed. The level of expression of gingipains was associated with those of miropin and certain T. forsythia proteases around teeth but not implants. Cumulatively, KLIKK-proteases and especially miropin, might play a role in pathogenesis of both periodontal and peri-implant diseases.
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Statins in nonsurgical and surgical periodontal therapy. A systematic review and meta-analysis of preclinical in vivo trials. J Periodontal Res 2017; 53:267-287. [PMID: 29211309 DOI: 10.1111/jre.12514] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/25/2017] [Indexed: 12/13/2022]
Abstract
The cholesterol-lowering drugs, statins, possess anti-inflammatory, antimicrobial and pro-osteogenic properties, and thus have been tested as an adjunct to periodontal treatment. The present systematic review aimed to answer the following focused research question: What is the effect of local and/or systemic statin use on periodontal tissues in preclinical in vivo studies of experimentally induced periodontitis (EIP) and/or acute/chronified periodontal defect (ACP) models? A literature search (of Medline/PubMed, Embase/Ovid, CENTRAL/Ovid) using the following main eligibility criteria was performed: (i) English or German language; (ii) controlled preclinical in vivo trials; (iii) local and/or systemic statin use in EIP and/or ACP models; and (iv) quantitative evaluation of periodontal tissues (i.e., alveolar bone level/amount, attachment level, cementum formation, periodontal ligament formation). Sixteen studies in EIP models and 7 studies in ACP models evaluated simvastatin, atorvastatin or rosuvastatin. Thirteen of the EIP (81%) and 2 of the ACP (29%) studies presented significantly better results in terms of alveolar bone level/amount in favor of statins. Meta-analysis based on 14 EIP trials confirmed a significant benefit of local and systemic statin use (P < .001) in terms of alveolar bone level/amount; meta-regression revealed that statin type exhibited a significant effect (P = .014) in favor of atorvastatin. Three studies reported a significantly higher periodontal attachment level in favor of statin use (P < .001). Complete periodontal regeneration was never observed; furthermore, statins did not exert any apparent effect on cementum formation. Neither local nor systemic use of statins resulted in severe adverse effects. Statin use in periodontal indications has a positive effect on periodontal tissue parameters, supporting the positive results already observed in clinical trials. Nevertheless, not all statins available have been tested so far, and further research is needed to identify the maximum effective concentration/dose and optimal carrier.
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Plasmacytoid dendritic cells drive acute asthma exacerbations. J Allergy Clin Immunol 2017; 142:542-556.e12. [PMID: 29054692 DOI: 10.1016/j.jaci.2017.08.032] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Revised: 07/17/2017] [Accepted: 08/23/2017] [Indexed: 02/07/2023]
Abstract
BACKGROUND Although acute exacerbations, mostly triggered by viruses, account for the majority of hospitalizations in asthmatic patients, there is still very little known about the pathophysiologic mechanisms involved. Plasmacytoid dendritic cells (pDCs), prominent cells of antiviral immunity, exhibit proinflammatory or tolerogenic functions depending on the context, yet their involvement in asthma exacerbations remains unexplored. OBJECTIVES We sought to investigate the role of pDCs in allergic airway inflammation and acute asthma exacerbations. METHODS Animal models of allergic airway disease (AAD) and virus-induced AAD exacerbations were used to dissect pDC function in vivo and unwind the potential mechanisms involved. Sputum from asthmatic patients with stable disease or acute exacerbations was further studied to determine the presence of pDCs and correlation with inflammation. RESULTS pDCs were key mediators of the immunoinflammatory cascade that drives asthma exacerbations. In animal models of AAD and rhinovirus-induced AAD exacerbations, pDCs were recruited to the lung during inflammation and migrated to the draining lymph nodes to boost TH2-mediated effector responses. Accordingly, pDC depletion after allergen challenge or during rhinovirus infection abrogated exacerbation of inflammation and disease. Central to this process was IL-25, which was induced by allergen challenge or rhinovirus infection and conditioned pDCs for proinflammatory function. Consistently, in asthmatic patients pDC numbers were markedly increased during exacerbations and correlated with the severity of inflammation and the risk for asthma attacks. CONCLUSIONS Our studies uncover a previously unsuspected role of pDCs in asthma exacerbations with potential diagnostic and prognostic implications. They also propose the therapeutic targeting of pDCs and IL-25 for the treatment of acute asthma.
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Effect of Osteotomy Preparation on Osseointegration of Immediately Loaded, Tapered Dental Implants. Adv Dent Res 2017; 28:34-41. [PMID: 26927486 DOI: 10.1177/0022034515624446] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The aim of the present preclinical in vivo study was to evaluate whether a modified "drill-only" protocol, involving slight underpreparation of the implant site, may have an effect on aspects of osseointegration of a novel bone-level tapered implant, compared with the "standard drilling" protocol involving taping and profiling of the marginal aspect of the implant socket. In each side of the edentulated and completely healed mandible of 11 minipigs, 2 tapered implants (8 mm long × 4.1 mm Ø, BLT; Institut Straumann AG, Basel, Switzerland) were installed either with the drill-only or the standard drilling protocol. Significantly lower average insertion torque values were recorded for the standard drilling protocol group (52 ± 29 Ncm) compared with the drill-only group (70 ± 27 Ncm) (t test, P ≤ 0.05); no significant difference was observed between the 2 groups regarding implant stability, by means of resonance frequency analysis (75 ± 8 vs. 75 ± 6, respectively). Half of the implants were immediately loaded and the rest were submerged, providing observation times of 8 or 4 wk, respectively. Non-decalcified histological and histomorphometric analysis of the implants with surrounding tissues showed no significant differences between the 2 drilling protocols regarding the distance from the implant platform to the first coronal bone-to-implant contact (f-BIC), the total bone-to-implant contact (BIC) as a percentage of the total implant perimeter, and the bone density in an area extending 1 mm laterally from the implant (BATA) within 2 rectangular regions of interest (ROIs) 4 mm in height, representing the coronal (parallel-walled) and apical (tapered) aspect of the implant (ROI 1 and ROI 2, respectively) in non-submerged implants. In general, marginal peri-implant bone levels were at or slightly apical to the implant platform, and large amounts of bone-to-implant contact were observed. In contrast, immediately loaded implants placed with the drill-only protocol showed statistically significantly lower BIC values (66% ± 13.7%) compared with those installed with the standard drilling protocol (74.8% ± 11.2%) (P = 0.018). In addition, although marginal bone levels were in most of the immediately loaded implants at or slightly apical to the implant platform, some of the implants installed with the drill-only protocol showed marginal bone loss and crater formation. Thus, in this model system, even slight underpreparation of the implant socket appeared to compromise osseointegration of immediately loaded bone-level tapered implants.
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SET9-Mediated Regulation of TGF-β Signaling Links Protein Methylation to Pulmonary Fibrosis. Cell Rep 2016; 15:2733-44. [PMID: 27292644 PMCID: PMC4920893 DOI: 10.1016/j.celrep.2016.05.051] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 02/14/2016] [Accepted: 05/12/2016] [Indexed: 12/15/2022] Open
Abstract
TGF-β signaling regulates a variety of cellular processes, including proliferation, apoptosis, differentiation, immune responses, and fibrogenesis. Here, we describe a lysine methylation-mediated mechanism that controls the pro-fibrogenic activity of TGF-β. We find that the methyltransferase Set9 potentiates TGF-β signaling by targeting Smad7, an inhibitory downstream effector. Smad7 methylation promotes interaction with the E3 ligase Arkadia and, thus, ubiquitination-dependent degradation. Depletion or pharmacological inhibition of Set9 results in elevated Smad7 protein levels and inhibits TGF-β-dependent expression of genes encoding extracellular matrix components. The inhibitory effect of Set9 on TGF-β-mediated extracellular matrix production is further demonstrated in mouse models of pulmonary fibrosis. Lung fibrosis induced by bleomycin or Ad-TGF-β treatment was highly compromised in Set9-deficient mice. These results uncover a complex regulatory interplay among multiple Smad7 modifications and highlight the possibility that protein methyltransferases may represent promising therapeutic targets for treating lung fibrosis. Set9 (Setd7) methylates Smad7 at lysine-70 Methylated Smad7 interacts with Arkadia and is rapidly degraded Set9 function is required for TGF-β-mediated activation of ECM genes Set9 function is required for bleomycin- or Ad-TGF-β-induced pulmonary fibrosis
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Effect of avocado/soybean unsaponifiables on ligature-induced bone loss and bone repair after ligature removal in rats. J Periodontal Res 2016; 51:332-41. [PMID: 26248485 DOI: 10.1111/jre.12312] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2015] [Indexed: 01/31/2023]
Abstract
BACKGROUND AND OBJECTIVE The aim of this study was to evaluate the effects of administration of avocado/soybean unsaponifiable (ASU), a drug that is commonly used in the treatment of rheumatoid arthritis, on ligature-induced bone loss and bone repair after ligature removal in rats. MATERIAL AND METHODS Eighty-four rats were randomly assigned to four groups of equal size and received a daily gavage of either sterile saline [control (CTR)] or ASU (0.6 mg/kg), starting 7 d before (ASU/-7), on the day of (ASU/0) or 7 d after (ASU/+7) periodontitis induction. Periodontitis was induced by placing silk ligatures into the gingival sulcus of the second maxillary molars for 7 d; after 7 d, the ligatures were removed. Seven rats from each group were sacrificed, 7, 15 or 30 d after ligature removal. Bone resorption was evaluated by histomorphometry and micro-computed tomography (micro-CT). Immunohistochemistry was used to evaluate the expression of TRAP, RANKL and alkaline phosphatase (ALP), and quantitative PCR (qPCR) was used to evaluate the levels of interleukin-1beta (Il1β), tumor necrosis factor alpha (Tnfα), interleukin-6 (Il-6), Rankl and Alp. Statistical analysis was performed using the Shapiro-Wilk test, ANOVA and Tukey's test for normal data, and using the Kruskall-Wallis and Dunnet's tests for non-normal data (p < 0.05). RESULTS Histomorphometry and micro-CT analysis showed greater bone resorption in the CTR group than in the ASU/0 (15 d) and ASU/+7 (7 and 15 d) groups. The CTR group also presented with a higher expression of TRAP (15 and 30 d) and RANKL (7 and 15 d) compared with ASU/0 and ASU/+7 groups. Similarly, qPCR analysis showed higher levels of Rankl and Il1β mRNAs, and lower levels of Alp mRNA, in the CTR group compared with all other groups (for all periods). CONCLUSION ASU exhibited a positive effect on bone repair following ligature-induced periodontitis in rats.
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Continuing professional development in implant dentistry in Europe. EUROPEAN JOURNAL OF DENTAL EDUCATION : OFFICIAL JOURNAL OF THE ASSOCIATION FOR DENTAL EDUCATION IN EUROPE 2014; 18 Suppl 1:33-42. [PMID: 24484518 DOI: 10.1111/eje.12087] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/11/2013] [Indexed: 06/03/2023]
Abstract
INTRODUCTION Training for dental practitioners in implant dentistry ranges from 1- or 2-day short Continuing Professional Development (CPD) courses to certificate/diploma programmes run by universities. In general, the teaching of implant dentistry in Europe lacks structure and standardisation. This paper aims to: (i) identify the current trends in CPD in implant dentistry in Europe; (ii) identify potential and limitations with regards to the design and implementation of CPD activities in implant dentistry; (iii) provide recommendations on the future structure and development of CPD activities in implant dentistry. METHODS A search of the literature was undertaken in PubMed for manuscripts published in English after 2000 reporting on CPD in dentistry and in implant dentistry in particular. In addition, an electronic survey was conducted, investigating the attitudes towards CPD among a wide group of stakeholders in implant dentistry education. CONCLUSIONS There is a wide diversity of educational pathways towards achieving competences in implant dentistry through CPD. At present, there is a need for improving the CPD structures in implant dentistry, strengthening the quality assurance and encouraging standardisation and transparency of the learning outcomes. Development of a structured CPD system with clearly defined educational objectives mapped against specific levels of competence is recommended.
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Current trends and status of continuing professional development in implant dentistry in Europe. EUROPEAN JOURNAL OF DENTAL EDUCATION : OFFICIAL JOURNAL OF THE ASSOCIATION FOR DENTAL EDUCATION IN EUROPE 2014; 18 Suppl 1:52-59. [PMID: 24484520 DOI: 10.1111/eje.12080] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/18/2013] [Indexed: 06/03/2023]
Abstract
INTRODUCTION Previous surveys have shown that newly graduated dentists, in most European countries, do not obtain adequate theoretical knowledge and, especially, clinical skills in implant dentistry (ID) through their undergraduate education and must therefore acquire knowledge and develop competencies through further postgraduate study. Moreover, clinicians, in general, need to continue to maintain the currency of their competence by undertaking ongoing continuing professional development (CPD). This seems particularly important in ID as techniques, and materials develop rapidly due to advances in biomedical technology. Despite recent developments, CPD in ID remains poorly organised with little standardisation or harmonisation across Europe. The objective of this survey was to explore the current status and trends within CPD education in ID in Europe. MATERIALS AND METHODS Stakeholders and opinion leaders associated with ID education were invited by email to fill an online questionnaire (closing date: 30th April 2013). Two hundred and forty-seven questionnaires were distributed, and two separate reminders were sent to participants in 38 European countries. The survey contained 14 multiple-choice questions, and the data were collected using SurveyMonkey© software, exported in SPSS (Inc, Chicago, IL, USA) format and analysed using descriptive statistics. RESULTS Two hundred respondents working in 24 countries replied to the survey (response rate of 81% of invitees and 63% of countries surveyed). The results demonstrated a wide divergence in the content and structure of CPD in ID in Europe. CONCLUSIONS Dentists need CPD to develop their skills and to maintain their competence in ID. There is an urgent need for structured and accredited CPD, which should be readily available to all dentists practising ID. It should have pre-determined learning objectives, delivered by accredited CPD providers and educators, and have assessable outcome measures to ensure the best possible impact on clinical practice and patient safety.
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Virtual tissue alignment and cutting plane definition--a new method to obtain optimal longitudinal histological sections. J Anat 2013; 224:85-94. [PMID: 24266502 DOI: 10.1111/joa.12140] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/16/2013] [Indexed: 11/28/2022] Open
Abstract
Histomorphometric evaluation of the buccal aspects of periodontal tissues in rodents requires reproducible alignment of maxillae and highly precise sections containing central sections of buccal roots; this is a cumbersome and technically sensitive process due to the small specimen size. The aim of the present report is to describe and analyze a method to transfer virtual sections of micro-computer tomographic (CT)-generated image stacks to the microtome for undecalcified histological processing and to describe the anatomy of the periodontium in rat molars. A total of 84 undecalcified sections of all buccal roots of seven untreated rats was analyzed. The accuracy of section coordinate transfer from virtual micro-CT slice to the histological slice, right-left side differences and the measurement error for linear and angular measurements on micro-CT and on histological micrographs were calculated using the Bland-Altman method, interclass correlation coefficient and the method of moments estimator. Also, manual alignment of the micro-CT-scanned rat maxilla was compared with multiplanar computer-reconstructed alignment. The supra alveolar rat anatomy is rather similar to human anatomy, whereas the alveolar bone is of compact type and the keratinized gingival epithelium bends apical to join the junctional epithelium. The high methodological standardization presented herein ensures retrieval of histological slices with excellent display of anatomical microstructures, in a reproducible manner, minimizes random errors, and thereby may contribute to the reduction of number of animals needed.
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A rat model for orthodontic translational expansive tooth movement. Orthod Craniofac Res 2013; 16:223-33. [PMID: 23796274 DOI: 10.1111/ocr.12025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/26/2013] [Indexed: 11/28/2022]
Abstract
OBJECTIVES To present the development of an experimental model in rats for translational expansive tooth movement. SETTING AND SAMPLE Section of Periodontology at Department of Dentistry Aarhus University. Twenty male Wistar rats in two pilot experimental settings plus seven animals without any intervention serving as controls. MATERIAL AND METHODS The second molar (group P1) or the second and third molar (group P2) in the maxillae of the animals were moved buccally using transpalatal β-titanium springs. In the group P2, two spring types (high force and low force) and two preangulations (0° passive or 30° torsion moment) were tested. The amount and type of tooth movement achieved and the resulting skeletal effect were assessed on microCT images, histological analysis was performed on few selected specimens. RESULTS Expansive translational root movement amounting half a tooth width was achieved. Comparison of the amount of tooth movement at the right and left side of the maxilla showed that the expansion was rather symmetrical in the P2 group. Skeletal widening of the maxilla contributed in the P2 group to approximately one-third of the total root movement, whereas two-thirds were dental movement. CONCLUSION With the model used in the P2 group, further research on translational expansive tooth movement and its effect on the periodontium can be pursued. In models for orthodontic expansion, it is strongly recommended to separately evaluate skeletal and dental effects.
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Likelihood Ratio Type Statistics for Repeated Measures Designs with Heterogeneous Covariance Matrices. COMMUN STAT-THEOR M 2013. [DOI: 10.1080/03610926.2011.592256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Validity of wax and acrylic as soft-tissue simulation materials used in in vitro radiographic studies. Dentomaxillofac Radiol 2012; 41:686-90. [PMID: 22933536 DOI: 10.1259/dmfr/33467269] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE To determine the thickness of wax and acrylic that provides a radiographic density similar to that of the human cheek. METHODS An intraoral film radiograph of the human cheek including a 40×30×3 mm reference aluminium block was recorded under standardized conditions in 61 subjects. Radiographic density was measured by a densitometer in ten randomly selected sites of the film to serve as the gold standard for density values of the cheek soft tissues. Thereafter, the density of series of radiographs of two tissue-simulating materials-wax and acrylic-in systematically increasing thicknesses (wax, 1.5-30 mm; acrylic, 2-40 mm) plus the reference block were measured and compared with the gold-standard values. RESULTS The radiographic density of wax with a thickness of 13-17 mm or acrylic with a thickness of 14.5 mm corresponded to the average density of the human cheek. CONCLUSION The soft tissues of the average human cheek can be simulated with 13-17 mm wax or 14.5 mm acrylic in in vitro radiographic studies.
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Growth and differentiation factors for periodontal regeneration: a review on factors with clinical testing. J Periodontal Res 2012; 47:545-53. [DOI: 10.1111/j.1600-0765.2012.01478.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Activin-A Overexpression in the Murine Lung Causes Pathology That Simulates Acute Respiratory Distress Syndrome. Am J Respir Crit Care Med 2012; 185:382-91. [DOI: 10.1164/rccm.201105-0784oc] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
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Maxillary sinus floor augmentation with Bio-Oss or Bio-Oss mixed with autogenous bone as graft in animals: a systematic review. Int J Oral Maxillofac Surg 2012; 41:114-20. [DOI: 10.1016/j.ijom.2011.08.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2010] [Revised: 04/18/2011] [Accepted: 08/31/2011] [Indexed: 10/16/2022]
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Activation of the canonical bone morphogenetic protein (BMP) pathway during lung morphogenesis and adult lung tissue repair. PLoS One 2012; 7:e41460. [PMID: 22916109 PMCID: PMC3423416 DOI: 10.1371/journal.pone.0041460] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2012] [Accepted: 06/22/2012] [Indexed: 02/05/2023] Open
Abstract
Signaling by Bone Morphogenetic Proteins (BMP) has been implicated in early lung development, adult lung homeostasis and tissue-injury repair. However, the precise mechanism of action and the spatio-temporal pattern of BMP-signaling during these processes remains inadequately described. To address this, we have utilized a transgenic line harboring a BMP-responsive eGFP-reporter allele (BRE-eGFP) to construct the first detailed spatiotemporal map of canonical BMP-pathway activation during lung development, homeostasis and adult-lung injury repair. We demonstrate that during the pseudoglandular stage, when branching morphogenesis progresses in the developing lung, canonical BMP-pathway is active mainly in the vascular network and the sub-epithelial smooth muscle layer of the proximal airways. Activation of the BMP-pathway becomes evident in epithelial compartments only after embryonic day (E) 14.5 primarily in cells negative for epithelial-lineage markers, located in the proximal portion of the airway-tree, clusters adjacent to neuro-epithelial-bodies (NEBs) and in a substantial portion of alveolar epithelial cells. The pathway becomes activated in isolated E12.5 mesenchyme-free distal epithelial buds cultured in Matrigel suggesting that absence of reporter activity in these regions stems from a dynamic cross-talk between endoderm and mesenchyme. Epithelial cells with activated BMP-pathway are enriched in progenitors capable of forming colonies in three-dimensional Matrigel cultures.As lung morphogenesis approaches completion, eGFP-expression declines and in adult lung its expression is barely detectable. However, upon tissue-injury, either with naphthalene or bleomycin, the canonical BMP-pathways is re-activated, in bronchial or alveolar epithelial cells respectively, in a manner reminiscent to early lung development and in tissue areas where reparatory progenitor cells reside. Our studies illustrate the dynamic activation of canonical BMP-pathway during lung development and adult lung tissue-repair and highlight its involvement in two important processes, namely, the early development of the pulmonary vasculature and the management of epithelial progenitor pools both during lung development and repair of adult lung tissue-injury.
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Evaluation of the RB-RB/LB-LB mnemonic rule for recording optimally projected intraoral images of dental implants: an in vitro study. Dentomaxillofac Radiol 2011; 41:298-304. [PMID: 22184473 DOI: 10.1259/dmfr/20861598] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE The aim of this study was to evaluate a simple mnemonic rule (the RB-RB/LB-LB rule) for recording intra-oral radiographs with optimal projection for the control of dental implants. METHODS 30 third-year dental students received a short lesson in the RB-RB/LB-LB mnemonic rule. The rule is as follows: if right blur then raise beam (RB-RB), i.e. if implant threads are blurred at the right side of the implant, the X-ray beam direction must be raised towards the ceiling to obtain sharp threads on both implant sides; if left blur then lower beam (LB-LB), i.e. if implant threads are blurred at the left side of the implant, the X-ray beam direction must be lowered towards the floor to obtain sharp threads on both implant sides. Intra-oral radiographs of four screw-type implants placed with different inclination in a Frasaco upper or lower jaw dental model (Frasaco GmbH, Tettnang, Germany) were recorded. The students were unaware of the inclination of the implants and were instructed to re-expose each implant, implementing the mnemonic rule, until an image of the implant with acceptable quality (subjectively judged by the instructor) was obtained. Subsequently, each radiograph was blindly assessed with respect to sharpness of the implant threads and assigned to one of four quality categories: (1) perfect, (2) not perfect, but clinically acceptable, (3) not acceptable and (4) hopeless. RESULTS For all implants, from one non-perfect exposure to the following, a higher score was obtained in 64% of the cases, 28% received the same score and 8% obtained a lower score. Only a small variation was observed among exposures of implants with different inclination. On average, two exposures per implant (range: one to eight exposures) were needed to obtain a clinically acceptable image. CONCLUSION The RB-RB/LB-LB mnemonic rule for recording intra-oral radiographs of dental implants with a correct projection was easy to implement by inexperienced examiners.
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IL-28A (IFN-λ2) modulates lung DC function to promote Th1 immune skewing and suppress allergic airway disease. EMBO Mol Med 2011; 3:348-61. [PMID: 21538995 PMCID: PMC3377081 DOI: 10.1002/emmm.201100142] [Citation(s) in RCA: 170] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Revised: 03/03/2011] [Accepted: 03/22/2011] [Indexed: 01/28/2023] Open
Abstract
IL-28 (IFN-λ) cytokines exhibit potent antiviral and antitumor function but their full spectrum of activities remains largely unknown. Recently, IL-28 cytokine family members were found to be profoundly down-regulated in allergic asthma. We now reveal a novel role of IL-28 cytokines in inducing type 1 immunity and protection from allergic airway disease. Treatment of wild-type mice with recombinant or adenovirally expressed IL-28A ameliorated allergic airway disease, suppressed Th2 and Th17 responses and induced IFN-γ. Moreover, abrogation of endogenous IL-28 cytokine function in IL-28Rα−/− mice exacerbated allergic airway inflammation by augmenting Th2 and Th17 responses, and IgE levels. Central to IL-28A immunoregulatory activity was its capacity to modulate lung CD11c+ dendritic cell (DC) function to down-regulate OX40L, up-regulate IL-12p70 and promote Th1 differentiation. Consistently, IL-28A-mediated protection was absent in IFN-γ−/− mice or after IL-12 neutralization and could be adoptively transferred by IL-28A-treated CD11c+ cells. These data demonstrate a critical role of IL-28 cytokines in controlling T cell responses in vivo through the modulation of lung CD11c+ DC function in experimental allergic asthma.
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Toll-like receptor 7-triggered immune response in the lung mediates acute and long-lasting suppression of experimental asthma. Am J Respir Crit Care Med 2010; 181:1207-16. [PMID: 20224068 DOI: 10.1164/rccm.200908-1255oc] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
RATIONALE Toll-like receptor (TLR) 7/8 ligands are promising candidate drugs for the treatment of allergic asthma and rhinitis. Although their clinical application depends on the development of strategies for topical administration to the lung, this has not been explored in preclinical disease models. OBJECTIVES To examine the therapeutic effectiveness, persistence of effect, and mode of action of intranasal TLR7 ligand administration in allergic airway disease. METHODS Wild-type, IFN-alpha receptor (IFN-alphaR)(-/-), IFN-gamma(-/-), CD8(-/-), TLR7(-/-), and radiation-induced chimeric mice deficient in hematopoietic TLR7 expression were subjected to an established model of allergic airway disease. R-848, a specific TLR7 agonist in mice, was administered prophylactically or therapeutically and effects of treatment on helper T-cell type 2 (Th2) responses, eosinophilia, goblet cell metaplasia, and airway hyperresponsiveness were assessed. MEASUREMENTS AND MAIN RESULTS Intranasal R-848 administration induced a transient immune response characterized by type I interferon production and infiltration of innate immune cells into the lung. This conferred long-term suppression of allergic airway disease via two complementary molecular processes, one mediated by type I interferons and providing acute protection by directly inhibiting effector Th2 responses, and one mediated by immunoregulatory CD8(+) T cells and inducing long-lasting protection by suppressing Th2 responses in an IFN-gamma-dependent manner. CONCLUSIONS Intranasal R-848 administration is an effective treatment for allergic airway disease. It hijacks an otherwise proinflammatory immune process triggered by TLR7 to mediate long-lasting disease suppression. This provides important insight into the efficacy and mode of action of TLR7 ligands in murine models of allergic airway disease and paves the way for their clinical application in humans.
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Formation of human cementum following different modalities of regenerative therapy. Clin Oral Investig 2005; 9:58-64. [PMID: 15635476 DOI: 10.1007/s00784-004-0288-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2004] [Accepted: 09/16/2004] [Indexed: 10/26/2022]
Abstract
The aim of the present study was to compare newly formed cementum following different types of regenerative therapy in humans. Eighteen patients, each displaying one advanced intrabony defect around teeth scheduled for extraction, were included in this study. The defects were treated with either guided tissue regeneration (GTR), enamel matrix protein derivative (EMD), EMD plus bioactive glass, bovine-derived xenograft (BDX), BDX plus GTR, or BDX plus EMD. After healing, the teeth were removed together with their surrounding soft and hard tissues. Cellular content, presence of artifactual splits between the new cementum and the old one or the dentin surface, and thickness of the new cementum were evaluated. Irrespective of treatment, the new cementum was of a reparative, cellular, extrinsic and intrinsic fiber type. There were no differences in cementum thickness among treatments. These findings indicate that in humans, (a) the new cementum formed after different types of regenerative therapy was, irrespective of the treatment, of a reparative, cellular, extrinsic and intrinsic fiber type, and (b) the regenerative modality does not seem to influence the type of newly formed cementum.
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Healing of human intrabony defects following regenerative periodontal therapy with a bovine-derived xenograft and guided tissue regeneration. Clin Oral Investig 2004; 8:70-4. [PMID: 14767696 DOI: 10.1007/s00784-004-0254-7] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2003] [Accepted: 01/08/2004] [Indexed: 10/26/2022]
Abstract
The purpose of the present study was to histologically evaluate the healing of human intrabony defects following treatment with either a bovine-derived xenograft (BDX) and guided tissue regeneration (GTR) [BDX + GTR] or a bovine-derived xenograft mixed with collagen (BDX Coll) and GTR [BDX Coll + GTR]. Eight patients with chronic periodontitis and each with one very deep intrabony defect around a tooth scheduled for extraction were treated with either a combination of BDX + GTR (five patients) or with BDX Coll + GTR (three patients). The postoperative healing was uneventful in all eight cases. After a healing period of 6 months, the teeth or roots were extracted together with some of their surrounding soft and hard tissues and subsequently fixed in 10% buffered formalin. Following decalcification in EDTA, the specimens were embedded in paraffin and 8-microm histological sections were cut in the mesio-distal direction, parallel to the long axes of the teeth. The sections were alternatively stained with hematoxylin and eosin, van Giesson's connective tissue stain or with the Ladevig's connective tissue staining method and examined under the light microscope. Generally, formation of new cementum with inserting collagen fibers was found in seven out of the eight treated cases, whereas in the remaining case (treated with BDX + GTR) the healing was characterized by formation of a long junctional epithelium along the debrided root surface and no formation of cementum or bone. In the specimens demonstrating periodontal regeneration the new cementum was always of a cellular type. In most cases, the graft particles were surrounded by bone. In some areas, the bone tissue around the graft particles was connected by perpendicularly inserting collagen fibers to the newly formed cementum on the root surface. The epithelium downgrowth stopped always at the most coronal part of the newly formed cementum. No remnants of the membrane material were observed in any of the biopsies. Connective tissue encapsulation of the graft particles was rarely observed and was limited to the most coronal part of the defects. The findings of the present study provide evidence that treatment of intrabony defects with both BDX + GTR and BDX Coll + GTR may enhance periodontal regeneration in humans.
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Evaluation of a cell-permeable barrier for guided tissue regeneration combined with demineralized bone matrix. Clin Oral Implants Res 2003; 14:812-8. [PMID: 15015959 DOI: 10.1046/j.0905-7161.2003.00966.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM To evaluate whether bone formation by guided tissue regeneration (GTR) and demineralized bone matrix (DBM) can be enhanced by the use of a cell-permeable Teflon barrier allowing the penetration of undifferentiated mesenchymal cells from the surrounding soft tissues. MATERIAL AND METHODS DBM was produced from the long bones of rats, and its bone-inductive properties were tested in three rats prior to the study by intramuscular implantation. Thirty, 4-month-old, male albino rats of the Wistar strain were used. Following surgical exposure of the mandibular ramus, a cell-permeable Teflon capsule, loosely packed with DBM, was placed with its opening facing the lateral surface of the ramus (test side). At the contralateral side, serving as control, a non-perforated (cell-occlusive) Teflon capsule, loosely packed with the same amount of DBM, was placed. After healing periods of 30, 60, and 120 days, groups of 10 animals were killed, and 40-70 microm thick undecalcified sections of the capsules were produced. RESULTS Computer-assisted planimetric measurements on the histological sections disclosed similar amounts of newly formed bone in both test and control capsules. After 4 months, the new bone in the control capsules occupied 45.0% of the cross-sectional area of the capsule, while it was 50.5% in the test capsules. This difference was not statistically significant (P<0.05). CONCLUSION Similar amounts of bone formed in cell-permeable and cell-occlusive capsules grafted with DBM, suggesting that invasion of undifferentiated mesenchymal cells from the surrounding soft tissues into the barrier-protected area is unnecessary for bone formation with GTR.
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Denaturation of demineralized bone matrix significantly reduces bone formation by guided tissue regeneration. Clin Oral Implants Res 2003; 14:804-11. [PMID: 15015958 DOI: 10.1046/j.0905-7161.2003.00965.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM To examine in a discriminating capsule model whether denaturation of demineralized bone matrix (DBM) by heating may influence bone formation. MATERIALS AND METHODS DBM was produced from the long bones of rats. Half the portion of DBM was denatured by heating in distilled water for 20 min at temperatures between 70 degrees C and 90 degrees C. Prior to the study, the destruction of the osteoinductive properties of the DBM was confirmed in three rats following intramuscular implantation. Thirty, 4-month-old, male albino rats of the Wistar strain were used in the study. Following surgical exposure of the mandibular ramus, a hemispherical Teflon capsule (internal diameter = 5.0 mm) was placed, with its open part facing the lateral aspect of the ramus. On one side (test side), the capsule was loosely packed with denatured DBM, while on the contralateral side, serving as control, the capsule was loosely packed with the same amount of non-denatured DBM. After healing periods of 30, 60, and 120 days, groups of 10 animals were killed and 40-70 microm thick undecalcified sections of the capsules were produced. Three sections from each specimen, representing the mid-portion of the capsule, were subjected to histological analysis and computer-assisted planimetric measurements. RESULTS Increasing amounts of newly formed bone were observed in both test and control capsules during the experimental period. At 4 months, the new bone formed in the control capsules occupied 46.7% of the cross-sectional area of the capsules, while it was only 19.1% in the test capsules (P<0.05). CONCLUSION Denaturation of DBM by heating significantly reduces bone formation by guided tissue regeneration.
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Deproteinized bovine bone and gentamicin as an adjunct to GTR in the treatment of intrabony defects: a randomized controlled clinical study. J Clin Periodontol 2003; 30:486-95. [PMID: 12795786 DOI: 10.1034/j.1600-051x.2003.00258.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVES To evaluate whether Bio-Oss used as an adjunct to guided tissue regeneration (GTR) improves the healing of 1- or 2-wall intrabony defects as compared with GTR alone, and to examine whether impregnation of Bio-Oss with gentamicin may have an added effect. MATERIAL AND METHODS Sixty patients, with at least one interproximal intrabony defect with probing pocket depth (PPD) > or =7 mm and radiographic evidence of an intrabony component (IC) > or =4 mm, were treated at random with either a resorbable membrane (GTR), a resorbable membrane in combination with Bio-Oss impregnated with saline (DBB-), a resorbable membrane in combination with Bio-Oss impregnated with gentamicin (DBB+), or with flap surgery (RBF). RESULTS All treatment modalities resulted in statistically significant clinical improvements after 1 year. Defects treated with GTR alone presented a probing attachment level (PAL) gain of 2.9 mm, a residual PPD (PPD12) of 4.9 mm, a radiographic bone level (RBL) gain of 3.1 mm, and a residual IC (IC12) of 2.7 mm. GTR combined with Bio-Oss did not improve the healing outcome (PAL gain: 2.5 mm; PPD12: 4.9 mm; RBL gain: 2.8 mm; IC12: 3.3 mm). Impregnation of the Bio-Oss with gentamicin 2% mg/ml resulted in clinical improvements (PAL gain: 3.8 mm; PPD12: 4.2 mm; RBL gain: 4.7 mm; IC12: 2.1 mm), superior to those of the other treatment modalities, but the difference was not statistically significant. Defects treated with only flap surgery showed the most inferior clinical response (PAL gain: 1.5 mm; PPD12: 5.1 mm; RBL gain: 1.2 mm; IC12: 4.2 mm) of all groups. CONCLUSION The results failed to demonstrate an added effect of Bio-Oss implantation in combination with GTR on the healing of deep interproximal 1- or 2-wall, or combined 1- and 2-wall intrabony defects compared with GTR alone. Local application of gentamicin, on the other hand, improved the treatment outcome but not to an extent that it was statistically significant.
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Abstract
OBJECTIVES To evaluate in a discriminating "capsule" model whether local application of gentamicin may have an added effect on bone formation produced by Bio-Oss and guide tissue regeneration (GTR). MATERIAL AND METHODS Thirty male 3-month-old Wistar rats were used. After elevation of muscle-periosteal flaps, a rigid hemispherical Teflon capsule, loosely packed with 0.025 g of Bio-Oss impregnated with 2 mg/ml gentamicin sulfate (Garamycin), was placed with its open part facing the lateral bone surface of the mandibular ramus (test) in one side of the jaw. A capsule filled only with Bio-Oss (control) was placed on the contralateral side of the jaw. After healing periods of 1, 2 and 4 months, groups of 10 animals were sacrificed and the specimens were processed for histological examination. The volumes of (1) the space created by the capsule, (2) newly formed bone, (3) Bio-Oss particles, (4) loose connective tissue, and (5) acellular space in the capsule were estimated by a point-counting technique in three to four histological sections of each specimen, taken by uniformly random sampling. RESULTS The histological evaluation showed limited but increasing bone fill in the capsules from 1 to 4 months in both the test and control sides. After 4 months, the newly formed bone occupied 11.9% (CV: 0.39) of the space created by the capsules at the test sides versus 13.2% (CV: 0.41) at the control sides. There was no statistical significant difference between test and control specimens at any observation time (p>0.05). CONCLUSION It is concluded that local application of gentamicin has no added effect on bone formation when combined with Bio-Oss and GTR.
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Abstract
AIM To evaluate in a discriminating capsule model whether bone formation by guided tissue regeneration (GTR) may be influenced by concomitant implantation of demineralized bone matrix (DBM). MATERIALS AND METHODS Thirty 4-month-old male albino rats of the Wistar strain were used in the study. Following surgical exposure of the mandibular ramus, a hemispherical, Teflon capsule (5.0 mm in diameter), loosely packed with a standardized amount of DBM, was placed with its open part facing the lateral bone surface of the ramus. At the contralateral side, an empty capsule was placed, serving as control. After healing periods of 15, 30, and 120 days, groups of 10 animals were sacrificed and 40-70 microm thick undecalcified sections of the capsules were produced. In the sections, the cross-sectional areas of (1) the space created by the capsule, (2) newly formed bone, (3) DBM particles, (4) loose connective tissue as well as the (5) height of the capsules, and (6) that of the newly formed bone were measured. RESULTS Increasing bone fill was observed in both test and control sites from 30 to 120 days. After 30 days of healing, the mean amount of bone was approx. 3% of the cross-sectional area of the capsules at the test sites while it was 8% in the control sites (p<0.05). However, no statistically significant differences were observed between the test (46%) and control (64%) sites after 120 days regarding any of the measured parameters (p>0.05). The newly formed bone in the DBM group at 120 days, on the other hand, appeared more dense than that in the control capsules. CONCLUSION DBM used as an adjunct to GTR did not provide any added effect on bone formation but increased the density of the newly formed bone.
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Deproteinized bovine bone used as an adjunct to guided bone augmentation: an experimental study in the rat. Clin Implant Dent Relat Res 2002; 3:156-65. [PMID: 11799706 DOI: 10.1111/j.1708-8208.2001.tb00136.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND Promising results have been reported following treatment of periodontal and peri-implant bone defects with deproteinized bovine bone grafts, but their influence on bone formation has not been clarified. PURPOSE The goal of this study was to examine whether implantation of deproteinized bovine bone (Bio-Oss, Geistlich AG, Wolhusen, Switzerland) influences bone formation when used as an adjunct to guided bone augmentation (GBA). MATERIALS AND METHODS A rigid, hemispherical, Teflon capsule was loosely packed with a standardized quantity of Bio-Oss and placed with its open part facing the lateral surface of the mandibular ramus (test) in 30 rats. At the contralateral side of the jaw, an empty capsule was placed (control). Groups of 10 animals were sacrificed after 1, 2, and 4 months. The volumes of the space created by the capsule and of the (1) newly formed bone, (2) remaining Bio-Oss particles, (3) soft connective tissue, and (4) acellular space in the capsule were estimated by a point-counting technique in three or four histologic sections, taken by uniformly random sampling. RESULTS Bone formation at 1 month was limited in both tests and controls. After 2 months, the mean volume of the newly formed bone occupied 9.0% of the space created by the capsule in the test specimens compared with 23.8% in the control specimens (p < .01). After 4 months, the respective figures were 11.6% (tests) versus 38.7% (controls) (p < .01). CONCLUSION It can be concluded that Bio-Oss, used as an adjunct to GBA, interferes with bone formation.
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A sketch of the health conditions and diseases in the hellenic area after the fall of the Byzantine empire (1453) until the Greek revolution (1821). HISTOIRE DES SCIENCES MEDICALES 2001; 17:163-7. [PMID: 11612214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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The effects of slow waves in the screening EEGs of pilot cadets on P300 ERP and memory scanning performance. AVIATION, SPACE, AND ENVIRONMENTAL MEDICINE 1997; 68:209-16. [PMID: 9056029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
BACKGROUND Electroencephalography (EEG) screening of pilot candidates has long been established but remains controversial. The EEG records of 0-15% of the test population demonstrate the presence of brief periods of slow waves (theta, 4-7.9 Hz and delta, 0-3.9 Hz). The significance of these EEG findings for pilot selection has not been defined. HYPOTHESIS We investigated whether the existence of slow waves in the EEG records of cadet pilots was related to differences in their cognitive performance. If so, the EEG could serve as a tool for cognitive assessment in candidate pilot screening. The relationship between spontaneous EEG slowing and cognitive performance has not been investigated although there is evidence of EEG slowing during the performance of short-term memory tasks. METHODS Some 116 screening EEG records were re-evaluated for the presence of slow wave activity. Cadets with positive records and a control group performed: a) a modified version of Sternberg's visual memory scanning task on a PC computer; and b) the auditory "OddBall" behavioral task for eliciting the P300 evoked response using the Nicolet Spirit Evoked Potential System. RESULTS Analysis of the behavioral and electrophysiological data was divided in EEG groups: a) Normal; b) Bilateral slowing only during hyperventilation; c) Bilateral slowing; d) Slowing with right dominance; and e) Slowing with left dominance, showed no significant difference among the groups for all parameters measured. CONCLUSIONS Brief periods of bilateral or focal EEG slow activity in the records of pilot cadets could not predict differences in cognitive function as this was assessed in these experiments. Specific neuropsychological screening procedures might be more valuable for this purpose than the standard EEG screening.
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Abstract
The authors assessed visual functions in 10 children after operations for congenital glaucoma. All the children had had one or more operations previously and it was found that the visual development of the child was affected.
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39
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Total hysterectomy in obstetrical practice. Int Surg 1970; 54:405-9. [PMID: 5489414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
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40
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[6 cases of cancer of the fallopian tubes]. REVUE FRANCAISE DE GYNECOLOGIE ET D'OBSTETRIQUE 1968; 63:545-7. [PMID: 5743620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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41
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[Cancer of the uterine cervix and prolapse]. GYNECOLOGIE ET OBSTETRIQUE 1968; 67:371-5. [PMID: 5687113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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42
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43
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[Labor induction by means of amniotomy]. Geburtshilfe Frauenheilkd 1966; 26:531-3. [PMID: 4956773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
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