The effect of combination treatment of CO2-laser irradiation and tetracalcium phosphate/dicalcium phosphate anhydrate on dentinal tubules blockage: an in vitro study.

The aim of this study was the evaluation of the in vitro efficacy of a carbon dioxide (CO2) laser, a tetracalcium phosphate/dicalcium phosphate anhydrate (TP/DP) desensitizer and the combination of the desensitizer and additional CO2 laser irradiation as a treatment modality for cervical dentin hypersensitivity. A total of 48 dental specimens, prepared from extracted human premolars and molars, were divided into four groups: a control group, a TP/DP desensitizer paste group, a CO2 laser (10.600-nm wavelength) group, and a paste and laser group. The specimens were coated with nail varnish except in the marked area and were then immersed in 2% methylene blue dye for 1 h. The specimens were then washed, dried, and cut longitudinally. Thereafter, photos of 40 dentin specimens were taken and evaluated. The area of penetration was assessed and reported as percentage of the dentin surface area. Additionally eight dental specimens were examined with the aid of a scanning electron microscope and evaluated. Significant differences in the penetration depth were found for all experimental groups compared to the control group. The lowest penetration area was detected in the paste-laser group (16.5%), followed by the laser (23.7%), the paste (48.5%), and the control group (86.2%). The combined treatment of the CO2 laser and a TP/DP desensitizer was efficient in sealing the dentinal surface and could be a treatment option for cervical dentin hypersensitivity.

Effects of enamel matrix derivative in nonsurgical periodontal therapy on pro-inflammatory profiles, microbial environment and clinical outcome: a randomized clinical trial.

OBJECTIVES: This study aimed to evaluate the impact of enamel matrix derivative (EMD) application following subgingival instrumentation of residual pockets in periodontitis patients on inflammatory host response, microbiological composition, and clinical outcome. METHODS: In this double-blinded randomized controlled trial, a total of 22 patients with generalized periodontitis stage III or IV presenting with ≥ 6 mm probing pocket depth (PPD) at re-evaluation after initial periodontal therapy were included. Participants were randomly allocated at a 1:1 ratio to subgingival instrumentation with (EMD +) or without (EMD-) non-surgical EMD application into the pocket. PPD, clinical attachment level (CAL), bleeding on probing (BoP), plaque index (PI), as well as a panel of pro-inflammatory cytokines and periodontal pathogen count in the gingival crevicular fluid (GCF) of the respective sites were evaluated at baseline (T0) and six months afterwards (T1). RESULTS: Both treatment groups showed a significant PPD reduction (EMD + 1.33 ± 1.15 mm, p < 0.001; EMD- 1.32 ± 1.01 mm, p < 0.001) as well as CAL gain (EMD + 1.13 ± 1.58 mm, p < 0.001; EMD- 0.47 ± 1.06 mm, p = 0.005) from T0 to T1. While no intergroup differences for PPD reduction were observed, CAL gain was higher in EMD + sites compared to EMD- (p = 0.009). No essential effects on cytokine expression as well as bacterial count were detected. CONCLUSIONS: Application of EMD as an adjunct to subgingival instrumentation of residual pockets yielded benefits regarding CAL gain; however, effects on PPD reduction, inflammatory cytokines, and bacterial count were negligible. TRIAL REGISTRATION: ClinicalTrials.gov (NCT04449393), registration date 26/06/2020. CLINICAL RELEVANCE: Based on the obtained results, additional non-surgical EMD application compared to subgingival instrumentation alone showed no clinically relevant effects on treatment outcome and underlying biological mechanisms.

Effects of customized CAD/CAM abutments on cytokine levels in peri-implant crevicular fluid during early implant healing: a pilot study.

OBJECTIVES: This study aimed to assess levels of biomarkers associated with inflammation and tissue destruction in peri-implant crevicular fluid (PICF) of implants provided with customized or standard healing abutments during early implant healing. MATERIALS AND METHODS: Thirty implants were placed in 22 patients with partial posterior edentulism. Subsequently, test group implants (n=15) received one-piece titanium abutments that were fabricated using computer-aided design/computer-aided manufacturing (CAD/CAM). Control group implants (n=15) were provided with standard abutments. PICF collection and standardized periapical radiographs were carried out at suture removal one week later, following crown delivery after 3 months and at 6 months. Expression of C-reactive protein (CRP), interferon-γ, tumor necrosis factor (TNF)-α, interleukin (IL)-1α, IL-1ß, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12A, IL-17A, macrophage inflammatory protein (MIP)-1α, matrix metalloproteinase (MMP)-13, osteopontin, osteoactivin, Receptor Activator of NF-κB (RANK), and TGF-ß were analyzed using a multiplex ELISA kit. RESULTS: Both groups showed a significant decrease in protein expression of CRP, IL-1ß, IL-6, IL-8, MIP-1α, osteopontin, osteoactivin, and TGF-ß, while MMP-13 levels increased during the observation period. A rise in OPG and RANK levels was detected among customized abutments. Expression of CRP was higher, whereas IL-1ß, IL-1α, and MIP-1α were decreased in control compared to test group implants after 6 months. Marginal bone loss did not depend on abutment modality. CONCLUSIONS: Both abutment types showed distinctive temporal expression of inflammatory biomarkers during 6 months following implant placement. TRIAL REGISTRATION: ISRCTN98477184, registration date 18/05/2022 CLINICAL RELEVANCE: Customized healing abutments exert similar effects on inflammation during early implant healing compared to standard healing abutments.

SARS-CoV-2-reactive T-cell receptors isolated from convalescent COVID-19 patients confer potent T-cell effector function.

Both B cells and T cells are involved in an effective immune response to SARS-CoV-2, the disease-causing virus of COVID-19. While B cells-with the indispensable help of CD4+ T cells-are essential to generate neutralizing antibodies, T cells on their own have been recognized as another major player in effective anti-SARS-CoV-2 immunity. In this report, we provide insights into the characteristics of individual HLA-A*02:01- and HLA-A*24:02-restricted SARS-CoV-2-reactive TCRs, isolated from convalescent COVID-19 patients. We observed that SARS-CoV-2-reactive T-cell populations were clearly detectable in convalescent samples and that TCRs isolated from these T cell clones were highly functional upon ectopic re-expression. The SARS-CoV-2-reactive TCRs described in this report mediated potent TCR signaling in reporter assays with low nanomolar EC50 values. We further demonstrate that these SARS-CoV-2-reactive TCRs conferred powerful T-cell effector function to primary CD8+ T cells as evident by a robust anti-SARS-CoV-2 IFN-γ response and in vitro cytotoxicity. We also provide an example of a long-lasting anti-SARS-CoV-2 memory response by reisolation of one of the retrieved TCRs 5 months after initial sampling. Taken together, these findings contribute to a better understanding of anti-SARS-CoV-2 T-cell immunity and may contribute to paving the way toward immunotherapeutics approaches targeting SARS-CoV-2.

The epidemiology of airplane headache: A cross-sectional study on point prevalence and characteristics in 50,000 travelers.

BACKGROUND: The current knowledge on the epidemiology and clinical manifestation of airplane headache is mostly derived from case series and small cohort studies without evidence from large populations. METHODS: This cross-sectional study was conducted over a five-month period in the arrival area of two international airports in Germany. 50,000 disembarking passengers were addressed about headaches during their flight to determine headache prevalence, and those confirming and willing to participate underwent a structured interview. RESULTS: Headache during travel was reported by 374 passengers (0.75%), and 301 underwent a structured interview. One hundred and one (0.2%) met the diagnostic criteria of airplane headache. Six passengers suffered from migraines and 134 from tension-type headaches. The differences in the age and gender distribution between the airplane headache and non-airplane headache groups were not statistically significant. The onset (79.2%), duration (82.2%), and location (73.3%) of airplane headache mostly complied with current diagnostic criteria but pain intensity (42.6%) and quality (42.6%) did less so. CONCLUSION: Our data suggest a substantially lower prevalence of airplane headaches than previously reported. The pain intensity and quality seem less characteristic than assumed, suggesting a need to refine the current diagnostic criteria.

Inflammation and necrosis syndrome is associated with alterations in blood and metabolism in pigs.

BACKGROUND: Swine inflammation and necrosis syndrome (SINS) can lead to significant clinical alterations at tail, ears, claws and other parts of the body in suckling piglets, weaners and fatteners. Clinical findings are associated with vasculitis, intima proliferation and thrombosis. The syndrome can be found in newborns, indicating a primarily endogenous aetiology. It has been hypothesized that SINS is triggered by gut-derived microbial-associated molecular patterns, causing derangements in liver metabolism and activity of peripheral white blood cells involving inflammation and blood haemostasis. In order to characterize these metabolic derangements of SINS for the first time, red and white blood counts, parameters of blood haemostasis, serum metabolites and acute phase proteins in the serum were analysed in 360 piglets, weaners and fatteners, each with significantly different SINS scores. RESULTS: SINS scores and haematological/clinical chemical parameters were significantly associated (P < 0.05), especially in weaners and fatteners. Higher degrees of clinical SINS were associated with increased numbers of monocytes and neutrophils. Blood coagulation was altered in weaners and a thrombocytopenia was found in fatteners. Additionally, acute phase proteins, especially C-reactive protein and fibrinogen were increased in serum. Serum metabolites and serum liver enzymes were slightly altered. Aspartate transaminase levels overall exceeded physiological limit and increased in parallel with SINS scores in fatteners. CONCLUSION: Clinical inflammation and necrosis at tail, ears, claws and other parts of the body were significantly associated with haematology and serum clinical chemistry, especially in weaners and fatteners. The involvement of inflammatory cells, blood coagulation, acute phase proteins and certain serum metabolites support the inflammatory-necrotising character of the syndrome and provide starting points for further studies to decipher its exact pathogenesis. The low to moderate variations seem less suitable for diagnostic use.

Anti-apoptotic effects of human gingival mesenchymal stromal cells on polymorphonuclear leucocytes.

OBJECTIVES: Polymorphonuclear leucocytes (PMNs) constitute the first line of host defence and are crucial in maintaining periodontal health. Their survival and function are modulated by mesenchymal stromal cells (MSCs) from different origin. Gingival MSCs (GMSCs) play an important role in maintaining oral health and in the initial inflammatory response. The present study aimed to investigate the effects of GMSCs on PMNs apoptosis and reactive oxygen species (ROS) production. METHODS: PMNs were either directly incubated with untreated, interleukin (IL)-1ß- or tumour necrosis factor (TNF)-α-treated GMSCs or stimulated with their conditioned media. Resulting ROS production was evaluated by dichlorofluorescin diacetate staining, whereas PMNs apoptosis was assessed by Annexin V staining, followed by flow cytometry analysis. RESULTS: While conditioned media of untreated and TNF-α-treated GMSCs did not affect apoptosis of PMNs, it was significantly delayed by conditioned media of GMSCs treated with IL-1ß. In direct co-culture, GMSCs exerted anti-apoptotic effects on PMNs independently of the previous stimulation. However, the strongest impact was observed by IL-1ß-treated GMSCs. ROS production of PMNs was not influenced by GMSCs or their conditioned media. CONCLUSION: This study demonstrates for the first time the immunomodulatory properties of GMSCs towards PMNs, revealing that IL-1ß enhances anti-apoptotic effects of GMSCs.

Urinary cortisol metabolites are reduced in MDR1 mutant dogs in a pilot targeted GC-MS urinary steroid hormone metabolome analysis.

P-glycoprotein (P-gp) is the gene product of the multidrug resistance gene (MDR1, syn. ABCB1) that normally restricts the transfer of cortisol across the blood-brain barrier. In the absence of P-gp, cortisol access to the hypothalamus is increased and, by feedback inhibition, this finally leads to lower endogenous plasma cortisol levels in dogs with homozygous nt230(del4) MDR1 mutation (MDR1-/- mutant dogs). While a previous study only focused on plasma cortisol levels, the present study used urinary steroid hormone metabolites to analyze cortisol metabolism in MDR1-/- mutant dogs. Morning void urine was collected from 23 MDR1-/- mutant and 16 MDR1+/+ normal dogs and was subjected to targeted GC-MS steroid hormone metabolome analysis. Seven cortisol metabolites, cortisol itself, and 13 other steroid metabolites were detected. In general, all cortisol metabolites were lower in the urine of the MDR1-/- mutant dogs, with allo-tetrahydro-cortisol and ß-cortol reaching the level of significance. In addition, 11-keto-pregnanetriol levels were significantly lower in the urine of the MDR1-/- mutant dogs, indicating that also the 17alpha-OH-progesterone-derived metabolism was altered. In conclusion, the present study provides the first steroid hormone metabolome analysis in the urine of MDR1-/- mutant dogs. Significant differences in the steroid metabolome of MDR1-/- mutant dogs point to a significant role of P-gp for cortisol metabolism and excretion and so indirectly also for hypothalamic-pituitary-adrenal axis regulation in dogs.

Effect of vitamin D3 on the osteogenic differentiation of human periodontal ligament stromal cells under inflammatory conditions.

OBJECTIVES: Vitamin D3 is known to activate osteogenic differentiation of human periodontal ligament stromal cells (hPDLSCs). Recently, inflammatory stimuli were shown to inhibit the transcriptional activity of hPDLSCs, but their effect on vitamin D3 -induced osteogenic differentiation is not known. The present study aimed to investigate whether the effects of 1,25-dihydroxvitamin D3 (1,25(OH)2 D3 ) and 25-hydroxvitamin D3 (25(OH)D3 ) on the osteogenic differentiation of hPDLSCs are also altered under inflammatory conditions. Furthermore, the expression of osteogenesis-related factors by hPDLSCs under osteogenic conditions was assessed in the presence of inflammatory stimuli. MATERIALS AND METHODS: Primary hPDLSCs of six donors were cultured in osteogenic induction medium containing either 1,25(OH)2 D3 (0-10 nM) or 25(OH)D3 (0-100 nM) in the presence and absence of Porphyromonas gingivalis lipopolysaccharide (LPS) or Pam3CSK4 for 7, 14 and 21 days. Osteogenic differentiation of hPDLSCs was evaluated by analysis of mineralization as assessed by Alizarin Red S staining and gene expression levels of osteogenesis-related factors osteocalcin, osteopontin and runt-related transcription factor 2 (RUNX2) were analysed with qPCR. RESULTS: Treatment with 1,25(OH)2 D3 significantly enhanced the osteogenic differentiation of hPDLSCs and their expression of osteocalcin and osteopontin. The 1,25(OH)2 D3 -triggered expression of osteogenesis-related factors was significantly lower in the presence of Pam3CSK4, but not P. gingivalis LPS. None of the inflammatory stimuli had significant effects on the 1,25(OH)2 D3 -induced osteogenic differentiation. 25(OH)D3 neither affected gene expression levels nor osteogenic differentiation of hPDLSCs cultured in osteogenic induction medium. CONCLUSION: The results of this study indicate that inflammatory stimuli also diminish the 1,25(OH)2 D3 -induced expression of osteogenesis-related factors in hPDLSCs under osteogenic conditions, while having no effect on the osteogenic differentiation.

Effects of Er:YAG laser irradiation of different titanium surfaces on osteoblast response.

The aim of this in vitro study was to evaluate the effects of erbium-doped yttrium aluminum garnet (Er:YAG) laser irradiation on titanium surface topography and the proliferation and differentiation of osteoblasts using standard clinical treatment settings. Er:YAG laser irradiation at two levels ((1): 160 mJ, pulse at 20 Hz; (2): 80 mJ, pulse at 20 Hz) was applied to moderately rough and smooth titanium disks before MG-63 osteoblast-like cells were cultured on these surfaces. Titanium surface and cell morphology were observed by scanning electron microscopy. Cell proliferation/viability was measured by CCK-8 test. Gene expression of alkaline phosphatase (ALP), osteocalcin (OC), osteoprotegerin (OPG), receptor activator of nuclear factor kappa-B ligand (RANKL), and collagen type 1 was measured by qPCR, and OPG and OC protein production was determined by enzyme-linked immunosorbent assay. Treatment with Er:YAG laser at 160 mJ/20 Hz markedly caused heat-induced fusion of titanium and cell condensation on moderately rough surfaces, but not in smooth surfaces. MG-63 proliferation/viability decreased after 5 days in moderately rough surfaces. The expression of ALP, OC, OPG, and collagen type 1 was unaffected by laser treatment at 160 mJ/20. Laser irradiation at 80 mJ/20 Hz enhanced RANKL gene expression after 5 days in moderately rough surfaces. Study results suggest that Er:YAG laser irradiation at clinically relevant setting has no essential effect on osteogenic gene and protein expression of osteoblasts. However, surface structure, cell attachment, and proliferation are influenced by both treatment protocols, which implies that caution should be taken in the clinical treatment of peri-implant diseases when Er:YAG laser is used.

Effect of interdental brush design on plaque during nonsurgical periodontal therapy.

OBJECTIVE: The aim of this randomized controlled trial was to evaluate the interproximal cleaning efficacy of waist-shaped compared with straight soft interdental brushes in patients undergoing nonsurgical periodontal therapy. MATERIALS AND METHODS: Ten patients diagnosed with periodontitis stage II or III were scheduled for nonsurgical periodontal therapy. Baseline plaque control record (PCR), modified approximal plaque index (API), papillary bleeding index (PBI), probing pocket depth (PPD), and bleeding on probing (BOP) were evaluated. Four interdental spaces of equal sizes were determined, and baseline plaque indices (PI) were assessed on eight surfaces of the respective adjacent teeth, resulting in 640 measuring positions. Interdental brushes with a straight or waist-shaped design were randomly allocated to the right or left side, and patients received oral hygiene instructions. Follow-up measurements including PCR, API, PBI, and site-specific PI were performed during initial nonsurgical periodontal therapy sessions and reevaluation which was undertaken 8 weeks afterwards. RESULTS: PCR, API, and PBI decreased significantly compared with baseline at each time point (p < 0.001). PPD (waist-shaped, baseline 4 mm (range, 2-9 mm) vs. reevaluation 3 mm (range, 1-6 mm); p < 0.001; straight, baseline 4 mm (range, 2-10) vs. reevaluation 3 mm (range, 1-6) mm; p < 0.001) and BOP (p = 0.008) showed significant reduction in both groups. Sub-analysis of site-specific areas including line angles and interproximal areas revealed no significant reduction of plaque during the observation period between both brush designs. No difference between straight and waist-shaped brushes regarding PPD or BOP decrease was found. CONCLUSION: The efficacy of both interdental brush designs concerning plaque control in patients undergoing nonsurgical periodontal therapy was similar. CLINICAL RELEVANCE: The use of interdental brushes is essential for biofilm removal in patients during initial periodontal therapy, regardless of brush design. CLINICAL TRIAL REGISTRATION: ISRCTNregistry (#ISRCTN24498365), http://www.isrctn.com/ISRCTN24498365.

Short-term results of the combined application of neodymium-doped yttrium aluminum garnet (Nd:YAG) laser and erbium-doped yttrium aluminum garnet (Er:YAG) laser in the treatment of periodontal disease: a randomized controlled trial.

OBJECTIVES: Nd:YAG and Er:YAG lasers have been previously used as an adjunct in periodontal therapy. The aim of this single-blinded randomized controlled clinical trial was to evaluate the efficacy of a combined application of Nd:YAG and Er:YAG laser irradiation in periodontal treatment. MATERIALS AND METHODS: Twenty-two patients with at least one site of ≥ 6 mm periodontal probing depth (PPD) after mechanical debridement with curettes and sonic instruments at periodontal reevaluation were included in the study. Patients were randomly allocated at a 1:1 ratio to either a combined Nd:YAG/Er:YAG laser therapy (test group) or a "turned off" laser therapy (control group). The Nd:YAG laser was used for periodontal pocket deepithelialization and to stabilize the resulting blood clot. The Er:YAG laser was primarily used for root surface modification. PPD (mm), clinical attachment level (CAL, mm), and bleeding on probing (BOP, +/-) at the site of laser treatment were evaluated at baseline and 2 months after treatment. RESULTS: The mean improvements from baseline to 2-month follow-up for PPD were significantly better in the laser group (2.05 ± 0.82 mm) compared to the control group (0.64 ± 0.90 mm; p = 0.001). Likewise, the gain in CAL was significantly better in the laser group (1.50 ± 1.10 mm) than in the control group (0.55 ± 1.01mm; p = 0.046). CONCLUSIONS: The combined application of Nd:YAG and Er:YAG laser irradiation as an adjunct to conventional non-surgical therapy showed a significant beneficial effect on periodontal treatment results. CLINICAL RELEVANCE: Combined Nd:YAG and Er:YAG laser irradiation could be a useful procedure additionally to conventional non-surgical periodontal therapy to improve periodontal treatment results. CLINICAL TRIAL REGISTRATION: ISRCTN registry #ISRCTN32132076.

The impact of 3D-printed LAY-FOMM 40 and LAY-FOMM 60 on L929 cells and human oral fibroblasts.

OBJECTIVES: LAY-FOMM is a promising material for FDA-approved Fused Deposition Modeling (FDM) applications in drug delivery. Here we investigated the impact on oral cells. MATERIALS AND METHODS: We evaluated the impact of 3D-printed LAY-FOMM 40, LAY-FOMM 60, and biocompatible polylactic acid (PLA) on the activity of murine L929 cells, gingival fibroblasts (GF), and periodontal ligament fibroblasts (PDLF) using indirect (samples on cells), direct monolayer culture models (cells on samples), and direct spheroid cultures with resazurin-based toxicity assay, confirmed by MTT and Live-dead staining. The surface topography was evaluated with scanning electron microscopy. RESULTS: The materials LAY-FOMM 40 and LAY-FOMM 60 led to a reduction in resazurin conversion in L929 cells, GF, and PDLF, higher than the impact of PLA in indirect and direct culture models. Fewer vital cells were found in the presence of LAY-FOMM 40 and 60 than PLA, in the staining in both models. In the direct model, LAY-FOMM 40 and PLA showed less impact on viability in the resazurin-based toxicity assay than in the indirect model. Spheroid microtissues showed a reduction of cell activity of GF and PDLF with LAY-FOMM 40 and 60. CONCLUSION: Overall, we found that LAY-FOMM 40 and LAY-FOMM 60 can reduce the activity of L292 and oral cells. Based on the results from the PLA samples, the direct model seems more reliable than the indirect model. CLINICAL RELEVANCE: A material modification is desired in terms of biocompatibility as it can mask the effect of drugs and interfere with the function of the 3D-printed device.

Pleiotropic effects of vitamin D3 on CD4+ T lymphocytes mediated by human periodontal ligament cells and inflammatory environment.

AIMS: Both, vitamin D3 and human periodontal ligament cells (hPDLCs) possess immunosuppressive properties, but their combined effect on immune cells has never been investigated. Here, we analysed the impact of vitamin D3 on the immunosuppressive properties of hPDLCs towards CD4+ T lymphocytes. MATERIAL AND METHODS: Allogenic CD4+ T lymphocytes were activated by phytohemagglutinin either in monoculture or co-culture with hPDLCs, in the presence or absence of IFN-γ and 1,25(OH)2 D3 . After 5 days, CD4+ T-lymphocyte proliferation, CD4+ CD25+ FoxP3+ regulatory T lymphocytes (Tregs ) proportion and IL-10, TGF-ß1 and IL-17A production were analysed. RESULTS: In monoculture, 1,25(OH)2 D3 suppressed CD4+ T-lymphocyte proliferation, increased the percentage of CD4+ FoxP3+ CD25+ FoxP3+ Tregs and enhanced IL-10 and TGF-ß1 production. In the presence of IFN-γ treated hPDLCs, 1,25(OH)2 D3 significantly increased CD4+ T-lymphocyte proliferation and decreased the percentage of CD4+ CD25+ FoxP3+ Tregs . IL-10 and IL-17A expression was significantly diminished by 1,25(OH)2 D3 , whereas TGF-ß1 was slightly increased. The effects of 1,25(OH)2 D3 in co-culture were reversed by inhibition of indoleamine-2,3-dioxygenase-1, prostaglandin-endoperoxide synthase and programmed cell death 1 ligand 1. 1,25(OH)2 D3 also suppressed the expression of these proteins in hPDLCs. CONCLUSION: Effects of vitamin D3 on CD4+ T lymphocyte are modified by hPDLCs depending on the microenvironment.

Extremely high canine C-reactive protein concentrations > 100 mg/l - prevalence, etiology and prognostic significance.

BACKGROUND: In human medicine, extremely high CRP (C-reactive protein) concentrations > 100 mg/l are indicators of bacterial infection and the need of antibiotic treatment. Similar decision limits for septic pneumonia are recommended for dogs but have not yet been evaluated for other organ systems. The aim of the retrospective study was to investigate the prevalence and evaluate dogs with CRP concentrations > 100 mg/l regarding the underlying etiology, the affected organ system and the prognostic significance. RESULTS: Prevalence of CRP > 100 mg/l was investigated in dogs presented between 2014 and 2015 and was 12%. For evaluation of etiology and organ systems, dogs with CRP > 100 mg/l presented between 2014 and 2016 were enrolled. Dogs were classified into 4 main disease categories, i.e. inflammatory, neoplastic, tissue damage or "diverse". Diseases were assigned to the affected organ system. If an organ classification was not possible, dogs were classified as "multiple". 147 dogs with CRP 101-368 mg/l were included and classified into disease categories: 86/147 (59%) with inflammatory etiology (among these, 23/86 non-infectious, 44/86 infectious (33/44 bacterial), 19/86 inflammation non-classifiable), 31/147 (21%) tissue damage, 17/147 (12%) neoplastic (all malignant) and 13/147 (9%) diverse diseases. The affected organ systems included 57/147 (39%) multiple, 30/147 (20%) trauma, 21/147 (14%) gastrointestinal tract, 10/147 (7%) musculoskeletal system, 8/147 (5%) respiratory tract, 7/147 (5%) urinary/reproductive tract, 6/147 (4%) skin/subcutis/ear, 6/147 (4%) central/peripheral nervous system and 2/147 (1%) heart. The disease group (p = 0.081) or organ system (p = 0.17) did not have an impact on CRP. Based on CRP, a detection of bacterial infection was not possible. The prognostic significance was investigated by determining the 3-months survival and hospitalization rate in a subgroup with known outcome. The 3-months survival rate was 46/73 (63%) while the majority 66/73 (90%) of patients was hospitalized. CONCLUSIONS: CRP concentrations > 100 mg/l are occasionally seen in a clinic population. They indicate a severe systemic disease of various etiologies with guarded prognosis. Extremely high CRP concentrations do not allow a conclusion of the underlying etiology or an identification of bacterial inflammation.

Response of Human Mesenchymal Stromal Cells from Periodontal Tissue to LPS Depends on the Purity but Not on the LPS Source.

Human periodontal ligament stromal cells (hPDLSCs) and gingival mesenchymal stromal cells (hGMSCs) are resident mesenchymal stromal cells (MSCs) of the periodontal tissue. The lipopolysaccharide (LPS) from Porphyromonas gingivalis is structurally distinct from that of other Gram-negative bacteria, and earlier studies linked this structural difference to a distinct virulence activity and the ability to activate toll-like receptor 2 (TLR-2), besides TLR-4 as commonly occurring upon LPS challenge. Later studies, in contrast, argue that TLR-2 activation by P. gingivalis LPS is due to lipoprotein contamination. In the present study, we aimed to define the influence of structure versus purity of P. gingivalis LPS on the immune response of hPDLSCs and hGMSCs. Cells were stimulated with commercially available "standard" P. gingivalis LPS, "ultrapure" P. gingivalis LPS, or "ultrapure" Escherichia coli LPS, and the expression of interleukin- (IL-) 8, IL-6, monocyte chemoattractant protein- (MCP-) 1, TLR-2, and TLR-4 was evaluated. The contribution of TLR-4 to the LPS-induced response was assessed using the specific TLR-4 inhibitor TAK-242. "Standard" P. gingivalis LPS induced significantly higher IL-8, IL-6, and MCP-1 production compared to the "ultrapure" LPS preparations, with no significant difference detectable for "ultrapure" LPS from P. gingivalis and E. coli. By using TAK-242, the response of hPDLSCs and hGMSCs to "ultrapure" LPS preparations was effectively inhibited to the levels comparable to those of nonstimulated controls. In contrast, high levels of response to "standard" LPS were observed, even in the presence of TAK-242. Our data show that the response of MSCs from periodontal tissue to LPS depends more on the purity of the LPS preparation than on the LPS source. Even a small amount of contaminating lipoproteins can drastically enhance the hPDLSCs' and hGMSCs; responsiveness to P. gingivalis LPS, which might also contribute to the progression of periodontal disease.

The efficacy of ultrasonic and PIPS (photon-induced acoustic streaming) irrigation to remove artificially placed dentine debris plugs out of an artificial and natural root model.

The aim was to validate an artificial resin 'root canal wall groove model' (RCWGM) mimicking the situation of natural roots with a groove of identical dimensions on debris removal out of these grooves, and to evaluate Erbium 'laser-activated irrigation' (LAI) with two conical tips at PIPS (photon-induced photoacoustic streaming) settings, with different activation times and different root canal positions on debris removal out of the grooves. A split RCWGM was used (resin blocks and roots of maxillary canines) with a canal size 40/0.06. The grooves in the apical third were filled with stained dentinal debris. Seventeen irrigation protocols (n = 20) were used: syringe-needle irrigation (3× 20 s), manual dynamic activation (1× 60 s), ultrasonically activated irrigation (UAI) with 25/25 Irrisafe (3× 20 s) and LAI (2940 nm Er:YAG) with X-Pulse or PIPS tips at PIPS settings (20 mJ, 50 µs, 20 Hz) and with the fibre (IN) or (OUT) the canal: IN during 1× 20 s, and OUT during 1× 20 s, 2× 20 s, 3× 20 s, 30 s, 2× 30 s and 1× 60 s. The quantity of remaining dentine debris in the groove was evaluated on a numerical scale. Statistical analysis was performed by means of proportional odds logistic regression, equivalence testing and Wald tests. The level of significance was set at 0.05. Resin models and the RCWGM with natural teeth can be called equivalent (log odds ratio 0.185). There were mostly no statistically significant differences for debris removal between UAI and LAI (p > 0.05) and between LAI with PIPS and X-Pulse (p > 0.05). Although not statistically different, the numbers of completely cleaned grooves were higher with LAI than with UAI for a 1-min activation, confirming findings from other studies. There is no difference in cleaning efficacy between X-Pulse and PIPS tips at PIPS settings.

Influence of two different cement space settings and three different cement types on the fit of polymer-infiltrated ceramic network material crowns manufactured using a complete digital workflow.

OBJECTIVES: The study evaluates the influence of two spacer settings and three resin luting materials on the marginal and internal fit of polymer-infiltrated ceramic network (PICN) material crowns manufactured using a complete digital workflow. METHODS: Optical impressions of fifty identical dies were performed using the 3M scanner (software version 5.0.2). Twenty crowns were designed using Ceramill Mind (version 3.4.10.1163), from which ten with spacer setting of 50 µm (G1) and ten with 80 µm (G2). Thirty crowns (spacer setting of 50 µm) were divided into three groups corresponding to the resin materials used as follows: RelyX Unicem (RX), Variolink Esthetic (VLE), and Nexus 3 (NX3). All crowns were milled from Vita Enamic blocks. After micro-CT scanning, absolute marginal discrepancy (AMD), internal gap (IG), total cement space volume (TCV), and marginal porosities (VP) were measured. RESULTS: Significant difference was detected on the VP between the RX and NX3 group (p = 0.033). The mean values of all parameters were the following: AMD (µm): G1 182.6, G2 253.7, RX 210.8, VLE 195.5, NX3 186.6; IG (µm): G1 215.6, G2 173.1, RX 171.1, VLE 198.6, NX3 203; TCV (mm3): G1 22.9, G2 20.49, RX 17.57, VLE 17.49, NX3 20.59; VP (mm3): G1 0.26, G2 0.34, RX 0.32, VLE 0.46, NX3 0.54. CONCLUSIONS: Fit of PICN material crowns was not significantly influenced by increasing the spacer settings and cementation with different resin materials. Additionally, RelyX Unicem showed significantly less porosities as compared with Nexus3. CLINICAL RELEVANCE: Both 50 µm and 80 µm virtual spacer settings can be suggested for the manufacture of PICN crowns when Ceramill Mind (version 3.4.10.1163) is used. Furthermore, a self-adhesive system can be recommended for the cementation.

The response of periodontal cells to kaolinite.

OBJECTIVES: The impact of kaolinite on human periodontal cells is yet unknown. The aim of the study was to assess the response of human periodontal cells to kaolinite. METHODS: Human periodontal cells were treated with kaolinite at reducing concentrations from 30 to 0.0015 mg/mL and with conditioned medium, which was depleted of kaolinite. Cell viability was evaluated with a resazurin-based toxicity assay, Live-Dead staining, and MTT assay and staining. The pro-angiogenic factors vascular endothelial growth factor (VEGF) and interleukin (IL)-6 and IL-8 were quantified via ELISA in periodontal fibroblasts. L-929, a standard cell-line used for cytotoxicity studies, served as control cell line. Composition of kaolinite was verified using energy-dispersive X-ray spectroscopy. RESULTS: Kaolinite in suspension but not in conditioned medium impaired cell viability dose-dependently. VEGF, IL-6, and IL-8 production was not substantially modulated by kaolinite or the conditioned medium in periodontal cells. CONCLUSION: Overall, kaolinite can decrease cell viability dose-dependently while conditioned medium showed no toxic effect. No pronounced impact of kaolinite on VEGF, IL-6, and IL-8 production was observed. This study provided first insights into the impact of kaolinite on human periodontal cells thereby inferring to the basis for the evaluation of kaolinite as a carrier in regenerative dentistry. CLINICAL RELEVANCE: Kaolinite, a clay mineral, is successfully used in medicine due to its favorable properties. Also, applications in conservative dentistry are described. However, the response of oral cells to kaolinite is still unclear. Here, we assessed the impact of kaolinite on human periodontal cells.

Contraction dynamics of dental pulp cell rod microtissues.

OBJECTIVES: The factors that contribute to the morphological changes of dental pulp cell-derived microtissues are unknown. Here, we investigated the contraction dynamics of rod-shaped microtissues derived from dental pulp cells and examined the underlying cell signaling pathways. METHODS: Human dental pulp cells were seeded into agarose molds to assemble into rod-shaped microtissues. Resazurin- and tetrazolium-based cytotoxicity assays, Live/Dead staining, and hematoxylin and eosin staining for histological evaluation of rods were performed. Rod contraction was evaluated and measured for a period of 10 days. The role of TGF-ß, phosphoinositide 3-kinase (PI3K)/AKT, and mitogen-activated protein kinase (MAPK) signaling pathway was analyzed. RESULTS: Dental pulp cells readily assembled into rods, maintaining the geometric shape for 48 h. Following this period, they condensed to form stable spheroidal structures that remained vital for 10 days from seeding. Inhibition of phosphoinositide 3-kinase signaling pathway by LY294002 significantly prolonged the diminution in the length of rods formed by dental pulp cells. TGF-ß and pharmacological inhibition of TGF-ß signaling did not show pronounced effects. CONCLUSION: Overall, dental pulp cells readily formed rod-shaped patterns of microtissues which, over a period of time, condensed into more stable spheroidal structures. Hence, technologies like bioprinting, using direct fabrication of microtissues need to consider the contraction dynamics. CLINICAL RELEVANCE: The field of regenerative endodontology will benefit from our findings as it can be applied as a novel platform to test the impact of pharmacological agents, biomaterials, and regenerative approaches including bioprinting.