Molecular Basis beyond Interrelated Bone Resorption/Regeneration in Periodontal Diseases: A Concise Review.

Periodontitis is the sixth most common chronic inflammatory disease, destroying the tissues supporting the teeth. There are three distinct stages in periodontitis: infection, inflammation, and tissue destruction, where each stage has its own characteristics and hence its line of treatment. Illuminating the underlying mechanisms of alveolar bone loss is vital in the treatment of periodontitis to allow for subsequent reconstruction of the periodontium. Bone cells, including osteoclasts, osteoblasts, and bone marrow stromal cells, classically were thought to control bone destruction in periodontitis. Lately, osteocytes were found to assist in inflammation-related bone remodeling besides being able to initiate physiological bone remodeling. Furthermore, mesenchymal stem cells (MSCs) either transplanted or homed exhibit highly immunosuppressive properties, such as preventing monocytes/hematopoietic precursor differentiation and downregulating excessive release of inflammatory cytokines. In the early stages of bone regeneration, an acute inflammatory response is critical for the recruitment of MSCs, controlling their migration, and their differentiation. Later during bone remodeling, the interaction and balance between proinflammatory and anti-inflammatory cytokines could regulate MSC properties, resulting in either bone formation or bone resorption. This narrative review elaborates on the important interactions between inflammatory stimuli during periodontal diseases, bone cells, MSCs, and subsequent bone regeneration or bone resorption. Understanding these concepts will open up new possibilities for promoting bone regeneration and hindering bone loss caused by periodontal diseases.

Vitamin C and Omega-3 Fatty Acid Intake Is Associated with Human Periodontitis-A Nested Case-Control Study.

Vitamins and omega-3 fatty acids (Ω3FA) modulate periodontitis-associated inflammatory processes. The aim of the current investigation was to evaluate associations of oral nutrient intake and corresponding serum metabolites with clinical severity of human periodontitis. Within the Food Chain Plus cohort, 373 periodontitis patients­245 without (POL) and 128 with tooth loss (PWL)­were matched to 373 controls based on sex, smoking habit, age and body mass index in a nested case-control design. The amount of oral intake of vitamins and Ω3FAs was assessed from nutritional data using a Food Frequency Questionnaire. Oral intake and circulatory bioavailability of vitamins and Ω3FA serum metabolomics were compared, using ultra-high-resolution mass spectrometry. Periodontitis patients exhibited a significantly higher oral intake of vitamin C and Ω3FA Docosapentaenoic acid (p < 0.05) compared to controls. Nutritional intake of vitamin C was higher in PWL, while the intake of Docosapentaenoic acid was increased in POL (p < 0.05) compared to controls. In accordance, serum levels of Docosapentaenoic acid were also increased in POL (p < 0.01) compared to controls. Vitamin C and the Ω3FA Docosapentaenoic acid might play a role in the pathophysiology of human periodontitis. Further studies on individualized nutritional intake and periodontitis progression and therapy are necessary.

Ascorbic Acid/Retinol and/or Inflammatory Stimuli's Effect on Proliferation/Differentiation Properties and Transcriptomics of Gingival Stem/Progenitor Cells.

The present study explored the effects of ascorbic-acid (AA)/retinol and timed inflammation on the stemness, the regenerative potential, and the transcriptomics profile of gingival mesenchymal stem/progenitor cells' (G-MSCs). STRO-1 (mesenchymal stem cell marker) immuno-magnetically sorted G-MSCs were cultured in basic medium (control group), in basic medium with IL-1ß (1 ng/mL), TNF-α (10 ng/mL) and IFN-γ (100 ng/mL, inflammatory-medium), in basic medium with AA (250 µmol/L) and retinol (20 µmol/L) (AA/retinol group) or in inflammatory medium with AA/retinol (inflammatory/AA/retinol group; n = 5/group). The intracellular levels of phosphorylated and total ß-Catenin at 1 h, the expression of stemness genes over 7 days, the number of colony-forming units (CFUs) as well as the cellular proliferation aptitude over 14 days, and the G-MSCs' multilineage differentiation potential were assessed. Next-generation sequencing was undertaken to elaborate on up-/downregulated genes and altered intracellular pathways. G-MSCs demonstrated all mesenchymal stem/progenitor cells characteristics. Controlled inflammation with AA/retinol significantly elevated NANOG (p < 0.05). The AA/retinol-mediated reduction in intracellular phosphorylated ß-Catenin was restored through the effect of controlled inflammation (p < 0.05). Cellular proliferation was highest in the AA/retinol group (p < 0.05). AA/retinol counteracted the inflammation-mediated reduction in G-MSCs' clonogenic ability and CFUs. Amplified chondrogenic differentiation was observed in the inflammatory/AA/retinol group. At 1 and 3 days, the differentially expressed genes were associated with development, proliferation, and migration (FOS, EGR1, SGK1, CXCL5, SIPA1L2, TFPI2, KRATP1-5), survival (EGR1, SGK1, TMEM132A), differentiation and mineral absorption (FOS, EGR1, MT1E, KRTAP1-5, ASNS, PSAT1), inflammation and MHC-II antigen processing (PER1, CTSS, CD74) and intracellular pathway activation (FKBP5, ZNF404). Less as well as more genes were activated the longer the G-MSCs remained in the inflammatory medium or AA/retinol, respectively. Combined, current results point at possibly interesting interactions between controlled inflammation or AA/retinol affecting stemness, proliferation, and differentiation attributes of G-MSCs.

Cell-Based Transplantation versus Cell Homing Approaches for Pulp-Dentin Complex Regeneration.

Regenerative dentistry has paved the way for a new era for the replacement of damaged dental tissues. Whether the causative factor is dental caries, trauma, or chemical insult, the loss of the pulp vitality constitutes one of the major health problems worldwide. Two regenerative therapies were introduced for a fully functional pulp-dentin complex regeneration, namely, cell-based (cell transplantation) and cell homing (through revascularization or homing by injection of stem cells in situ or intravenously) therapies, with each demonstrating advantages as well as drawbacks, especially in clinical application. The present review is aimed at elaborating on these two techniques in the treatment of irreversibly inflamed or necrotic pulp, which is aimed at regenerating a fully functional pulp-dentin complex.

Toll-like Receptor Expression Profile of Human Stem/Progenitor Cells Form the Apical Papilla.

INTRODUCTION: Stem/progenitor cells from the apical papilla (SCAPs) demonstrate remarkable regenerative and immunomodulatory properties. During their regenerative events, SCAPs, similar to other stem/progenitor cells, could interact with their local inflammatory microenvironment via their expressed toll-like receptors (TLRs). The present study aimed to describe for the first time the unique TLR expression profile of SCAPs. METHODS: Cells were isolated from the apical papilla of extracted wisdom teeth (n = 8), STRO-1 immunomagnetically sorted, and cultured to obtain single colony-forming units. The expression of CD14, 34, 45, 73, 90, and 105 were characterized on the SCAPs, and their multilineage differentiation potential was examined to prove their multipotent aptitude. After their incubation in basic or inflammatory medium (25 ng/mL interleukin 1 beta, 103 U/mL interferon gamma, 50 ng/mL tumor necrosis factor alpha, and 3 × 103 U/mL interferon alpha), a TLR expression profile for SCAPs under uninflamed as well as inflamed conditions was respectively generated. RESULTS: SCAPs demonstrated all predefined stem/progenitor cell characteristics. In basic medium, SCAPs expressed TLRs 1-10. The inflammatory microenvironment up-regulated the expression of TLR1, TLR2, TLR4, TLR5, TLR6, and TLR9 and down-regulated the expression of TLR3, TLR7, TLR8, and TLR10 in SCAPs under the inflamed condition. CONCLUSIONS: The present study defines for the first time a distinctive TLR expression profile for SCAPs under uninflamed and inflamed conditions. This profile could greatly impact SCAP responsiveness to their inflammatory microenvironmental agents under regenerative conditions in vivo.

Mesenchymal Stem/Progenitor Cells: The Prospect of Human Clinical Translation.

Mesenchymal stem/progenitor cells (MSCs) are key players in regenerative medicine, relying principally on their differentiation/regeneration potential, immunomodulatory properties, paracrine effects, and potent homing ability with minimal if any ethical concerns. Even though multiple preclinical and clinical studies have demonstrated remarkable properties for MSCs, the clinical applicability of MSC-based therapies is still questionable. Several challenges exist that critically hinder a successful clinical translation of MSC-based therapies, including but not limited to heterogeneity of their populations, variability in their quality and quantity, donor-related factors, discrepancies in protocols for isolation, in vitro expansion and premodification, and variability in methods of cell delivery, dosing, and cell homing. Alterations of MSC viability, proliferation, properties, and/or function are also affected by various drugs and chemicals. Moreover, significant safety concerns exist due to possible teratogenic/neoplastic potential and transmission of infectious diseases. Through the current review, we aim to highlight the major challenges facing MSCs' human clinical translation and shed light on the undergoing strategies to overcome them.

Retinol/inflammation affect stemness and differentiation potential of gingival stem/progenitor cells via Wnt/ß-catenin.

BACKGROUND AND OBJECTIVE: Inflammatory cytokines impact the course of periodontal disease, repair, and regeneration. Vitamin A and its metabolites are inflammation-modulatory biomolecules, affecting cellular pluripotency. The aim of this study was to investigate the effect of retinol and periodontal inflammatory cytokines (IL-1ß/TNF-α/IFN-γ) on pluripotency and proliferative properties of gingival mesenchymal stem/progenitor cells (G-MSCs), for the first time. MATERIAL AND METHODS: Human G-MSCs (n = 5) were STRO-1 immuno-magnetically sorted, characterized and expanded in basic medium (control group), in basic medium with IL-1ß (1 ng/mL), TNF-α (10 ng/mL), and IFN-γ (100 ng/mL) (inflammatory group), in basic medium with retinol (20 µmol/L) (retinol group) and with retinol added to the inflammatory group (inflammatory/retinol group). ß-catenin levels at 1 hour, cellular proliferation over 14 days, and colony-forming units (CFUs) at 14 days were investigated. Pluripotency gene expressions were examined at 1, 3, and 5 days via reverse transcription-polymerase chain reaction (RT-PCR). Multilineage differentiation potential was evaluated, following 5 days priming, using qualitative and quantitative histochemistry and RT-PCR. RESULTS: G-MSCs were CD14- , CD34- , CD45- , CD73+ , CD90+ , CD105+ , and showed mesenchymal stem/progenitor cells' hallmarks, CFUs, and multilineage differentiation potential. Intracellular ß-catenin significantly declined in the stimulated groups (P < 0.001, Friedman test). Cellular proliferation at 72 hours was most prominent in the control and inflammatory group [Median cell numbers (Q25/Q75); 6806 (4983/7312) and 5414 (4457/7230), respectively], followed by an upsurge in the retinol group. At 14 days, the retinol group exhibited the highest CFUs [Median CFUs (Q25/Q75); 35 (20/58), P = 0.043, Wilcoxon signed-rank]. Nanog was most expressed in the inflammatory and retinol group [Median gene expression/PGK1 (Q25/Q75); 0.0006 (0.0002/0.0014) and 0.0005 (0.0003/0.0008)]. Inflammation significantly upregulated Sox2 expression [0.0002 (0.0008/0.0005)], while its expression was diminished in the retinol and inflammatory/retinol group (P < 0.001, Friedman test). Inflammatory/retinol group exhibited the highest multilineage differentiation potential. CONCLUSION: Controlled short-term inflammatory/retinol stimuli activate the Wnt/ß-catenin pathway, affecting G-MSCs' pluripotency, proliferation, and differentiation. The present findings provide further insights into the inflammatory-regenerative interactions and their modulation potential for G-MSCs-mediated periodontal repair/regeneration.

Assessment of Different Root Canal Preparation Techniques with Rotary Nickel-Titanium Instruments by Novice Students.

This study investigated which preparation strategy for root canals leads to the best technical preparation quality, and moreover, which is perceived to be performed best by novice students. Sixty-four students were recruited to prepare one simulated root canal with each of the following: FlexMaster files (F), Mtwo files (M), and Reciproc files (R). After preparation, the students assessed the different instrument systems through a questionnaire. The technical quality of the root canal preparations was evaluated by the centering ratio of the preparation. A total of 186 prepared root canals were submitted for evaluation. With R, significantly better centered preparations were achieved when compared to M and F (p < 0.001). The students evaluated R faster than M and F, and evaluated F significantly (p < 0.05) slower than R and M. M was rated as the easiest system to learn and to handle, as well as the best at reaching the working length; therefore, it was evaluated as the overall favorite of the students. A difference was found between the students' perceptions and their achieved technical quality of root canal preparations.

Validation of multivariable models for predicting tooth loss in periodontitis patients.

OBJECTIVES: A large number of multivariable models which associate independent variables with the outcome tooth loss exist. Directly or indirectly, these make predictions as to the relative risk of tooth loss. We aimed to validate six of these prediction models. METHODS: We applied each model, if needed after adaptions, in a cohort of 301 compliant periodontitis patients who had been under supportive periodontal treatment (SPT) in a university setting over 21.7 ± 5.6 years. The models employed a range of tooth-level and patient-level parameters. Model accuracy, that is, the ability to rightly predict tooth loss during SPT using baseline parameters, was investigated by the area under the receiver-operating-characteristics curve (AUC). RESULTS: Most models showed low accuracy (AUC ranged between 0.52 and 0.67). The classification model from Avila et al. (2009) Journal of Periodontology, 80, 476-491, expressing the risk of tooth loss in five grades, was most accurate (mean AUC: 0.67, 95%CI: 0.65/0.69). When applying this model, the risk of false-positively predicting tooth loss was high, except when the highest grade (i.e. a tooth being considered as having a hopeless prognosis) was used. In this case, the specificity was 84% and the sensitivity 46%. CONCLUSIONS: Predicting tooth loss in this specific cohort of periodontitis patients was only limitedly possible.

TLR-induced immunomodulatory cytokine expression by human gingival stem/progenitor cells.

During therapeutic application, mesenchymal stem cells (MSCs) may interact with their environment via their expressed toll-like-receptors (TLRs) leading to pro- or anti-inflammatory immune responses. The present study aimed to describe the gingival margin-derived stem/progenitor cells' (G-MSCs) TLR-induced immune regulatory response to specific TLR agonists. Gingival cells were obtained, immunomagnetically sorted via anti-STRO-1 antibodies and seeded out to achieve colony forming units (CFUs). G-MSCs were investigated for stem cell characteristics and TLR expression. Specific TLR agonists were applied and m-RNA expression of pro- and anti-inflammatory factors was analyzed via real-time polymerase chain reaction. G-MSCs showed all characteristics of stem/progenitor cells. All TLR agonists induced pro-inflammatory cytokines, except for the TLR3 agonist, which significantly promoted the anti-inflammatory response. (p⩽0.05, Wilcoxon-Signed-Ranks-Test). TLR-induced immunomodulation by G-MSCs could impact their therapeutic potential in vivo. Two distinctive pro-inflammatory and an anti-inflammatory TLR-induced phenotypes of G-MSCs become noticeable in this study.

Global smoking-attributable burden of periodontal disease in 186 countries in the year 2015.

AIM: We aimed to quantify the smoking-attributable burden of periodontal disease (PD). METHODS: The association between smoking and PD was evaluated. Population, smoking and PD data from the Global Burden of Disease Study were used, and the burden in different sex and age groups in 186 countries in 2015 calculated, adjusted for PD prevalence and numbers of cigarettes smoked. No adjustment was performed in a sensitivity analysis. RESULTS: The global smoking-attributable burden was 251,160 disability-adjusted life years (DALYs; 95% uncertainty interval: 190,721-324,241; sensitivity analysis: 344,041 DALYs) or 38.5 million cases. The burden was lower in females than males, and highest in the age group of the 50- to 69-year-olds. On super-regional level, the burden was highest in South-East Asia, East Asia and Oceania (83,052 DALYs), and high-income North America and Asia Pacific (55,362 DALYs). On regional level, it was highest in East Asia (70,845 DALYs), South Asia (30,808 DALYs) and North Africa and the Middle East (24,095 DALYs). On national level, it was highest in China (69,148 DALYs), India (29,362 DALYs) and the United States (12,714 DALYs). The relative smoking-attributable burden ranged between >25% in Suriname and <1% in Chad. CONCLUSIONS: There is great need to monitor and tackle the smoking-attributable burden of PD.

TLR expression profile of human alveolar bone proper-derived stem/progenitor cells and osteoblasts.

Alveolar bone proper-derived mesenchymal stem/progenitor cells (AB-MSCs) and alveolar osteoblasts (OBs) are pivotal cells with positive attributes in regenerative medicine. During regenerative approaches, AB-MSCs may interact with their surrounding environment via their expressed toll-like-receptors (TLRs). This study aimed to depict for the first time the TLRs expression profile of AB-MSCs and OBs. Cells were isolated from human alveolar bone proper, and STRO-1-immunomagnetically sorted to segregate AB-MSCs and OBs. Cell populations were separately seeded out to obtain single colony forming units (CFUs), and were characterized for CD14, CD34, CD45, CD73, CD90, CD105, and CD146 expression as well as for their multilineage differentiation potential. Following incubation of AB-MSCs and OBs in basic medium, their TLRs expression profiles were characterized at mRNA and protein levels. In contrast to OBs, AB-MSCs showed all predefined mesenchymal stem/progenitor cell characteristics. At a protein level, AB-MSCs showed a distinctive expression profile of TLRs 1, 2, 3, 4, 5, 6, 7, 8, and 10 in different quantities, without TLR9 expression. According to their median expression values, TLR2 was the highest expressed, followed by TLRs 4, 5, 7, 1, 10, 8, 3, and finally 6. In contrast, OBs did not express TLR3 and TLR9. According to their median expression values they further showed a different sequence of TLRs expression, with TLR2 highest expressed, followed by TLRs 10, 4, 7, 5, 1, 8, and 6. This study describes for the first time the characteristic TLRs expression profile of AB-MSCs as well as OBs, which could impact their specific sensitivity to pathogenic as well as body tissue compounds, and their therapeutic potential in-vivo.

Porphyromonas gingivalis lipopolysaccharides affect gingival stem/progenitor cells attributes through NF-κB, but not Wnt/ß-catenin, pathway.

AIM: This study investigates for the first time the effect of Porphyromonas gingivalis lipopolysaccharides (Pg-LPS) on proliferative/regenerative aptitudes of gingival stem/progenitor cells (G-MSCs). MATERIAL AND METHODS: G-MSCs (n = 5) were treated by 0, 10 ng/ml, 100 ng/ml, 1 µg/ml or 10 µg/ml Pg-LPS. At 1 hour, Toll-like receptor 4 (TLR-4) expression and NF-κB and Wnt/ß-catenin signalling pathways were examined. Colony-forming unit assay was conducted at day 12. At 24 and 48 hours, MTT test, ALP activity, mRNA for tumour necrosis factor-α (TNF-α), interleukin-6, collagen-I (Col-I), collagen-III, RUNX-2, alkaline phosphatase (ALP), osteonectin and protein expression of interleukin-6 and TNF-α were analysed. RESULTS: With increasing Pg-LPS, TLR-4 was upregulated, pNF-κB-p65 rose from median (Q25/Q75) 6.56% (4.19/7.90) to 13.02% (8.90/16.50; p = 0.002) and pNF-κB-p65/tNF-κB-p65 from 0.14(0.10/0.17) to 0.30(0.21/0.42; p = 0.002). pß-Catenin, tß-catenin and pß-catenin/tß-catenin showed no differences. Increasing Pg-LPS concentration increased cell numbers from 288.00(72.98/484.32) to 861.39 (540.41/1599.94; p = 0.002), ALP mRNA from 0.00(0.00/0.01) to 0.56(0.00/1.90; p = 0.004) and TNF-α from 32.47(12.11/38.57) to 45.32(28.68/48.65; p = 0.036). Over time, ALP activity increased from 0.89(0.78/0.95) to 1.90(1.83/2.09; p < 0.001), mRNA for TNF-α from 0.00(0.00/0.12) to 0.01(0.00/0.06; p = 0.007), mRNA for Col-I from 82.70(0.03/171.50) to 124.00(52.85/232.50; p = 0.019), while mRNA for RUNX-2 decreased from 1.73(0.92/3.20) to 0.84(0.48/1.47; p = 0.005). CONCLUSIONS: Pg-LPS upregulated G-MSCs' proliferation, without attenuation of their regenerative potential. The effects were NF-κB, but not Wnt/ß-catenin, pathway dependent.

Dental implants combined with sinus augmentation: What is the merit of bone grafting? A systematic review.

PURPOSE: The aim of the present study was to systematically assess the current evidence on the effect of nongrafted compared to graft-assisted maxillary sinus floor elevation on implant survival/failure, endosinus bone gain, crestal bone loss, and bone density around dental implants. MATERIALS AND METHODS: MEDLINE-PubMed, Cochrane-CENTRAL, and EMBASE databases were searched up to November 2015 for randomized controlled trials (RCTs) and controlled clinical trials-(CCTs), evaluating dental implants placed in combination with maxillary sinus elevation without and with bone grafting. Implant survival/failure served as the primary outcome, whereas endosinus bone gain, crestal bone loss, and bone density around dental implants were secondary outcomes. To assess possible bias, the Cochrane risk of bias tool was used. Data were extracted and a meta-analysis performed where appropriate. RESULTS: Independent screening of 3180 papers resulted in six eligible experiments. Heterogeneity was observed among experiments. One experiment showed low, three unclear, and two a high risk of bias. The assessed outcomes showed no significant long-term differences between groups. CONCLUSION: Within the limit of the current systematic review, nongrafted maxillary sinus floor elevation seems to be characterized by new bone formation and high implant survival rate comparable to bone-graft-assisted maxillary sinus floor augmentation. Further long-term studies are needed before definitive conclusions can be made.

Gingival Mesenchymal Stem/Progenitor Cells: A Unique Tissue Engineering Gem.

The human gingiva, characterized by its outstanding scarless wound healing properties, is a unique tissue and a pivotal component of the periodontal apparatus, investing and surrounding the teeth in their sockets in the alveolar bone. In the last years gingival mesenchymal stem/progenitor cells (G-MSCs), with promising regenerative and immunomodulatory properties, have been isolated and characterized from the gingival lamina propria. These cells, in contrast to other mesenchymal stem/progenitor cell sources, are abundant, readily accessible, and easily obtainable via minimally invasive cell isolation techniques. The present review summarizes the current scientific evidence on G-MSCs' isolation, their characterization, the investigated subpopulations, the generated induced pluripotent stem cells- (iPSC-) like G-MSCs, their regenerative properties, and current approaches for G-MSCs' delivery. The review further demonstrates their immunomodulatory properties, the transplantation preconditioning attempts via multiple biomolecules to enhance their attributes, and the experimental therapeutic applications conducted to treat multiple diseases in experimental animal models in vivo. G-MSCs show remarkable tissue reparative/regenerative potential, noteworthy immunomodulatory properties, and primary experimental therapeutic applications of G-MSCs are very promising, pointing at future biologically based therapeutic techniques, being potentially superior to conventional clinical treatment modalities.

Toll-like Receptor Expression Profile of Human Dental Pulp Stem/Progenitor Cells.

INTRODUCTION: Human dental pulp stem/progenitor cells (DPSCs) show remarkable regenerative potential in vivo. During regeneration, DPSCs may interact with their inflammatory environment via toll-like receptors (TLRs). The present study aimed to depict for the first time the TLR expression profile of DPSCs. METHODS: Cells were isolated from human dental pulp, STRO-1-immunomagnetically sorted, and seeded out to obtain single colony-forming units. DPSCs were characterized for CD14, CD34, CD45, CD73, CD90, CD105, and CD146 expression and for their multilineage differentiation potential. After incubation of DPSCs in basic or inflammatory medium (interleukin-1ß, interferon-γ, interferon-α, tumor necrosis factor-α), TLR expression profiles were generated (DPSCs and DPSCs-i). RESULTS: DPSCs showed all characteristics of stem/progenitor cells. In basic medium DPSCs expressed TLRs 1-10 in different quantities. The inflammatory medium upregulated the expression of TLRs 2, 3, 4, 5, and 8, downregulated TLRs 1, 7, 9, and 10, and abolished TLR6. CONCLUSIONS: The current study describes for the first time the distinctive TLR expression profile of DPSCs in uninflamed and inflamed conditions.

Periodontal regeneration employing gingival margin-derived stem/progenitor cells in conjunction with IL-1ra-hydrogel synthetic extracellular matrix.

AIM: This study investigated the periodontal regenerative potential of gingival margin-derived stem/progenitor cells (G-MSCs) in conjunction with IL-1ra-releasing hyaluronic acid synthetic extracellular matrix (HA-sECM). MATERIALS AND METHODS: Periodontal defects were induced at four sites in eight miniature pigs in the premolar/molar area (-4 weeks). Autologus G-MSCs were isolated from the free gingival margin and magnetically sorted, using anti-STRO-1 antibodies. Colony formation and multilineage differentiation potential were tested. The G-MSCs were expanded and incorporated into IL-1ra-loaded/unloaded HA-sECM. Within every miniature pig, four periodontal defects were randomly treated with IL-1ra/G-MSCs/HA-sECM (test group), G-MSCs/HA-sECM (positive-control), scaling and root planing (SRP; negative control-1) or left untreated (no-treatment group; negative control 2). Differences in clinical attachment level (ΔCAL), probing depth (ΔPD), gingival recession (ΔGR), radiographic defect volume (ΔRDV), and changes in bleeding on probing (BOP) between baseline and 16 weeks post-transplantation, as well as periodontal attachment level (PAL), junctional epithelium length (JE), connective tissue adhesion (CTA), cementum regeneration (CR) and bone regeneration (BR) at 16 weeks post-transplantation were evaluated. RESULTS: Isolated G-MSCs showed stem/progenitor cell characteristics. IL-1ra loaded and unloaded G-MSCs/HA-sECM showed higher ΔCAL, ΔPD, ΔGR, PAL, CR and BR as well as a lower JE compared to their negative controls and improved BOP. CONCLUSION: G-MSCs in conjunction with IL-1ra-loaded/unloaded HA-sECM show a significant periodontal regenerative potential.

Periodontal probing versus radiographs for the diagnosis of furcation involvement.

BACKGROUND: Decisions in periodontal therapy for multirooted teeth are essentially based on accurate diagnosis of the furcation involvement (FI). Furcation probing (FP) is still the basic diagnostic measure, although the assessment may be difficult. The aim of this study is to evaluate the validity of FP and radiographic assessment of FI compared with visual assessment during open flap surgery (OFS). METHODS: In this retrospective clinical cohort study, 215 participants with periodontal disease and at least one molar treated with OFS were enrolled, and a total of 834 molars were assigned for FI by FP and in radiographs analyzed by an experienced (EE) and less experienced examiner (LE). For the investigation, 143 panoramic radiographs (OPGs) and 77 intra-oral radiographs (I-Os) were evaluated. RESULTS: The Class of FI by FP was confirmed in 56%, whereas 15% were overestimated and 29% underestimated. FI Class 0 and I had been detected with high probability (74% and 54%, respectively). Of all FI Class III, 57% were detected correctly by radiographs and 32% by FP. FP and OFS revealed a weighted κ-coefficient (κw) = 0.588; radiographs and OFS had κw = 0.542 (OPG κw = 0.555 and I-O κw = 0.521). The interrater reliability for radiographs was dependent on the experience of the examiner (EE κw = 0.618; LE κw = 0.426). CONCLUSIONS: Experience in analyzing conventional radiographs increases the potential of correct diagnosis of advanced FI. The reliability of FP compared with radiographic assessment depends on the anatomy and location of the tooth. Both diagnostic tools should be used in cases of suspected FI.

Influence of psychological attachment patterns on periodontal disease - a pilot study with 310 compliant patients.

OBJECTIVES: Psychosocial variables have received increased attention in periodontology. Attachment theory adds to known risk factors by linking early interactional experiences with adult tendencies of stress-regulation, health behaviour, symptom reporting, and healthcare utilization. The study investigates associations between attachment patterns and periodontal parameters. METHODS: Within the context of a longitudinal study on periodontal diseases, 310 patients with aggressive (AgP) and chronic periodontitis (CP) filled out questionnaires on psychological attachment patterns. The influence of attachment style on health behaviour, treatment attendance and utilization, and periodontal variables was tested. RESULTS: We found associations between psychological attachment anxiety on smoking and higher number of session use, independent of disease severity, which was more pronounced for women. Patients with higher attachment avoidance attended periodontal treatment later when diagnosed with CP and earlier with AgP. For men, we found differential associations for attachment avoidance and anxiety and number of teeth at beginning of treatment. CONCLUSION: Psychological attachment patterns are a promising target for understanding periodontal disease in addition to known psychosocial risk factors.