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Statement of problem Although studies have reported on selective laser melting (SLM)-fabricated removable partial dentures (RPDs), research addressing the trueness of SLM-fabricated RPD metal frameworks is sparse. Purpose The purpose of this in vitro study was to evaluate the trueness of powdered cobalt-chromium (Co-Cr) or titanium-6 aluminum-4 vanadium (Ti-6Al-4V) alloy frameworks for RPDs fabricated by SLM. Material and methods A digital scan of a Kennedy class II mandible typodont was obtained to design an RPD framework by using a computer-aided design (CAD) software program (denoted as CRF). Two experimental groups of frameworks were fabricated from the CRF by using SLM in alloys of Co-Cr (SLM-Co-Cr, n=6) and in Ti-6Al-4V (SLM-Ti-6Al-4V, n=6) while a control group was fabricated by using traditional lost-wax casting following stereolithography (CA-Co-Cr, n=6). In total, 18 RPD frameworks were digitally scanned (denoted as CRF), with each scan then superimposed on the CRF and evaluated for discrepancies by using a 3D analysis software program. A nonparametric Kruskal-Wallis test was performed to determine differences in trueness among groups (α=.05). Results The CA-Co-Cr group showed the highest discrepancy between CEF and CRF. Statistically significant differences were found between the CA-Co-Cr and SLM-fabricated groups (P=.03 for Co-Cr, and P=.016 for Ti-6Al-4V). However, no significant difference was found between the SLM-Co-Cr and SLM-Ti-6Al-4V groups (P=.787). Conclusions SLM-fabricated RPD frameworks exhibited higher trueness than CA-Co-Cr fabricated ones, indicating the potential of selective laser melting to produce the geometric shapes required for accurate dental restorations.

Statement of problem The effect of heat treatment on the microstructure and mechanical properties of cobalt-chromium (Co-Cr) removable partial denture (RPD) frameworks fabricated by selective laser melting (SLM) is not well understood. Purpose The purpose of this in vitro study was to evaluate the suitability of SLM-fabricated Co-Cr alloys followed by heat treatment as a framework for RPDs by determining the microstructure and mechanical properties. Material and methods Dumbbell specimens and RPD frameworks were fabricated by using SLM followed by heat treatment. The effects of the heat treatment on the microstructure were studied by using optical microscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD). Tensile and insertion and removal tests were performed to study the mechanical responses of selective laser melting followed by heat treatment specimens, including the ultimate tensile strength (UTS), 0.2% yield strength (0.2% YS), elongation (E), and retentive forces. Specimens fabricated by using the traditional lost-wax process were used as a control (casting) group. Results X-ray diffraction indicated that the γ-face-centered cubic phase dominated SLM and selective laser melting followed by heat treatment specimens. Results from optical microscopy and SEM showed microstructural changes under different fabrication and postprocessing heat treatments; it was difficult to observe the grain boundary in the SLM group, whereas submicrometer-scale grains had formed in the selective laser melting followed by heat treatment group. The selective laser melting followed by heat treatment group exhibited the highest elongation and retentive forces compared with the casting and SLM groups. Conclusions SLM increased the mechanical properties of Co-Cr alloys. Postprocessing heat treatment further enhanced the tensile ductility. It is suggested that SLM followed by heat treatment is an efficient strategy for fabricating RPD frameworks.

Manufacturing three-dimensional (3D) objects with polymers/bioceramic composite materials has been investigated in recent years. In this study, we manufactured and evaluated solvent-free polycaprolactone (PCL) and beta-tricalcium phosphate (β-TCP) composite fiber as a scaffold material for 3D printing. To investigate the optimal ratio of feedstock material for 3D printing, the physical and biological characteristics of four different ratios of β-TCP compounds mixed with PCL were investigated. PCL/β-TCP ratios of 0 wt.%, 10 wt.%, 20 wt.%, and 30 wt.% were fabricated, with PCL melted at 65 °C and blended with β-TCP with no solvent added during the fabrication process. Electron microscopy revealed an even distribution of β-TCP in the PCL fibers, while Fourier transform infrared spectroscopy demonstrated that the biomaterial compounds remained intact after the heating and manufacturing process. In addition, adding 20% β-TCP into the PCL/β-TCP mixture significantly increased hardness and Young’s Modulus by 10% and 26.5%, respectively, suggesting that PCL-20 has better resistance to deformation under load. Cell viability, alkaline phosphatase (ALPase) activity, osteogenic gene expression, and mineralization were also observed to increase according to the amount of β-TCP added. Cell viability and ALPase activity were 20% higher with PCL-30, while upregulation for osteoblast-related gene expression was better with PCL-20. In conclusion, PCL-20 and PCL-30 fibers fabricated without solvent exhibited excellent mechanical properties, high biocompatibility, and high osteogenic ability, making them promising materials for 3D printing customized bone scaffolds promptly, sustainably, and cost-effectively.

Osteoarthritis (OA) and rheumatoid arthritis (RA) are two of the most common types of arthritis. Both are characterized by the infiltration of a number of proinflammatory cytokines into the joint microenvironment. miRNAs play critical roles in the disease processes of arthritic disorders. However, little is known about the effects of miRNAs on critical inflammatory cytokine production with OA and RA progression. Here, we found higher levels of proinflammatory cytokines including interleukin 1 beta (IL-1β), interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α) in human OA and RA synovial fibroblasts (SFs) compared with normal SFs. Searches of open-source microRNA (miRNA) software determined that miR-let-7c-5p and miR-149-5p interfere with IL-1β, IL-6 and TNF-α transcription; levels of all three proinflammatory cytokines were lower in human OA and RA patients compared with normal controls. Anti-inflammatory agents dexamethasone, celecoxib and indomethacin reduced proinflammatory cytokine production by promoting the expression of miR-let-7c-5p and miR-149-5p. Similarly, ibuprofen and methotrexate also enhanced miR-let-7c-5p and miR-149-5p expression in human SFs. The evidence suggests that increasing miR-let-7c-5p and miR-149-5p expression is a novel strategy for OA and RA.

The aim of this study was to evaluate the effects of at-home and in-office bleaching agents on esthetic CAD-CAM materials after red wine immersion by measuring their optical properties. Sixty specimens were prepared out of three esthetic CAD-CAM materials: Vita Enamic, Celtra Duo, and Ceresmart (n = 20). All specimens were immersed in a red wine solution, and color measurements were performed. Specimens were randomly divided (n = 10) according to the bleaching procedure (in office, at home), bleaching durations were set to 3 time points, and color measurements were performed. According to the Commission Internationale de l’Eclairage (CIE) L* a* b* parameters, CIEDE2000 color differences (ΔE00), translucency parameters (TP00), and whiteness index values (ΔWID) after wine staining and after bleaching were calculated. Data were analyzed using the Mann–Whitney U-test, the Kruskal–Wallis test, and a two-way analysis of variance (ANOVA) (α = 0.05). ΔE00, ΔTP00, and ΔWID decreased with an increase in bleaching treatment. ΔE00 after the final bleaching treatment of in-office bleaching ranged from 1.7 to 2.0, whereas those of in-office treatment ranged from 0.4 to 1.1. All ΔTP00 and ΔWID after the final treatment were below the 50:50% perceptibility thresholds (ΔTP00 < 0.6, and ΔWID < 0.7). Significant differences in ΔE00, ΔTP00, and ΔWID among esthetic CAD-CAM materials were found between CD and CE. In the present study, color recovery after at-home and in-office bleaching appeared to be material-dependent. In-office bleaching showed more effective recovery comparing to at-home bleaching.

Polyetherketoneketone (PEKK) is an alternative material for use in removable partial denture frameworks; these frameworks must exhibit antibacterial properties to reduce the risk of periodontal disease. In the present study, silver nanoparticles (AgNPs) were synthesized via the reduction of silver nitrate with sodium borohydride in a solution containing polyvinyl pyrrolidone (PVP). Transmission electron microscope images and dynamic light scattering confirmed that metallic nanoparticles had been created with an average size of 32 nm. Furthermore, the coating of the PEKK polymeric substrate with 0.5% AgNPs was carried out using an epoxy resin lining at room temperature. Fourier transform infrared (FTIR) spectra confirmed the successful transfer of the AgNP-in-resin lining onto the polymeric substrate. Scanning electron microscopy and atomic force microscopy confirmed that the AgNPs had been uniformly deposited onto the PEKK specimens. Finally, the antibacterial activity of the specimens was tested against Porphyromonas gingivalis. An inhibition zone of 22.5 mm and an antibacterial rate of 83.47% were found for the PEKK coated with 0.5% AgNPs (0.5% Ag-PEKK) compared to an untreated polyetheretherketone (PEEK) substrate, evidencing that 0.5% Ag-PEKK has potential antibacterial properties for implant applications.

There is insufficient information about the effects of the thickness of externally characterized stains or glazes on CIELAB color parameters and the translucency parameter (TP) of 5 mol% yttria partially stabilized zirconia (5Y-PSZ). The present study evaluated the effect of a thickness reduction of the externally characterized or glazed layer on its CIE2000 color parameters and TPTwenty-eight specimens were sectioned from 5Y-PSZ blanks. Three brands of powdered stains (namely VI, SH, and IV) and a glaze (GL) were used to extrinsically stain the specimen surfaces (n = 7 per group). After measuring the final thickness and color, specimens of each group were carefully ground and finally polished. The reduced thickness was carefully controlled in decrements of 0.02 mm on the characterized stains or glazed layers at each reduction cycle until the surface of the un-stained zirconia was exposed. The CIELAB color parameters of specimens were measured using a spectrophotometer. Subsequently, differences in lightness (∆L'), chroma (∆C'), and hue (∆H'), and TPThere were no significant differences in lightness, chroma, hue, or TPIncreasing the thickness of externally characterized stains decreased the lightness and caused the alternation of chroma and hue, whereas these phenomena were not observed in the glazed group. There was a slight change of CIE2000 color parameters and TPThe application and thickness of externally characterized stains can sensitively affect CIE2000 color parameters and translucency of 5Y-PSZ.

Many revolutionary approaches are on the way pertaining to the high occurrence of tooth decay, which is an enduring challenge in the field of preventive dentistry. However, an ideal dental care material has yet to be fully developed. With this aim, this research reports a dramatic enhancement in the rehardening potential of surface-etched enamels through a plausible synergistic effect of the novel combination of γ-polyglutamic acid (γ-PGA) and nano-hydroxyapatite (nano-HAp) paste, within the limitations of the study. The percentage of recovery of the surface microhardness (SMHR%) and the surface parameters for 9 wt% γ-PGA/nano-HAp paste on acid-etched enamel were investigated with a Vickers microhardness tester and an atomic force microscope, respectively. This in vitro study demonstrates that γ-PGA/nano-HAp treatment could increase the SMHR% of etched enamel to 39.59 ± 6.69% in 30 min. To test the hypothesis of the rehardening mechanism and the preventive effect of the γ-PGA/nano-HAp paste, the surface parameters of mean peak spacing (Rsm) and mean arithmetic surface roughness (Ra) were both measured and compared to the specimens subjected to demineralization and/or remineralization. After the treatment of γ-PGA/nano-HAp on the etched surface, the reduction in Rsm from 999 ± 120 nm to 700 ± 80 nm suggests the possible mechanism of void-filling within a short treatment time of 10 min. Furthermore, ΔRa-I, the roughness change due to etching before remineralization, was 23.15 ± 3.23 nm, while ΔRa-II, the roughness change after remineralization, was 11.99 ± 3.90 nm. This statistically significant reduction in roughness change (p < 0.05) implies a protective effect against the demineralization process. The as-developed novel γ-PGA/nano-HAp paste possesses a high efficacy towards tooth microhardness rehardening, and a protective effect against acid etching.

This study evaluated the new bone formation potential of micro–macro biphasic calcium phosphate (MBCP) and Bio-Oss grafting materials with and without dental pulp-derived mesenchymal stem cells (DPSCs) and bone marrow-derived mesenchymal stem cells (BMSCs) in a rabbit calvarial bone defect model. The surface structure of the grafting materials was evaluated using a scanning electron microscope (SEM). The multipotent differentiation characteristics of the DPSCs and BMSCs were assessed. Four circular bone defects were created in the calvarium of 24 rabbits and randomly allocated to eight experimental groups: empty control, MBCP, MBCP+DPSCs, MBCP+BMSCs, Bio-Oss+DPSCs, Bio-Oss+BMSCs, and autogenous bone. A three-dimensional analysis of the new bone formation was performed using micro-computed tomography (micro-CT) and a histological study after 2, 4, and 8 weeks of healing. Homogenously porous structures were observed in both grafting materials. The BMSCs revealed higher osteogenic differentiation capacities, whereas the DPSCs exhibited higher colony-forming units. The micro-CT and histological analysis findings for the new bone formation were consistent. In general, the empty control showed the lowest bone regeneration capacity throughout the experimental period. By contrast, the percentage of new bone formation was the highest in the autogenous bone group after 2 (39.4% ± 4.7%) and 4 weeks (49.7% ± 1.5%) of healing (p &lt, 0.05). MBCP and Bio-Oss could provide osteoconductive support and prevent the collapse of the defect space for new bone formation. In addition, more osteoblastic cells lining the surface of the newly formed bone and bone grafting materials were observed after incorporating the DPSCs and BMSCs. After 8 weeks of healing, the autogenous bone group (54.9% ± 6.1%) showed a higher percentage of new bone formation than the empty control (35.3% ± 0.5%), MBCP (38.3% ± 6.0%), MBCP+DPSC (39.8% ± 5.7%), Bio-Oss (41.3% ± 3.5%), and Bio-Oss+DPSC (42.1% ± 2.7%) groups. Nevertheless, the percentage of new bone formation did not significantly differ between the MBCP+BMSC (47.2% ± 8.3%) and Bio-Oss+BMSC (51.2% ± 9.9%) groups and the autogenous bone group. Our study results demonstrated that autogenous bone is the gold standard. Both the DPSCs and BMSCs enhanced the osteoconductive capacities of MBCP and Bio-Oss. In addition, the efficiency of the BMSCs combined with MBCP and Bio-Oss was comparable to that of the autogenous bone after 8 weeks of healing. These findings provide effective strategies for the improvement of biomaterials and MSC-based bone tissue regeneration.

Rheumatoid arthritis (RA) is an autoimmune disorder that is characterized by increasing levels of proinflammatory cytokines. The ubiquitous enzyme dipeptidyl peptidase-4 (DPP4, also known as CD26) regulates different immune disorders, although the effects of DPP4 in RA are uncertain. Here, we found lower levels of DPP4 in RA synovial tissues compared with normal tissues. DPP4 levels were also lower in a rat collagen-induced arthritis model than in control (healthy) rats. Overexpression of DPP4 or exogenous treatment of RA synovial fibroblasts with DPP4 reduced levels of proinflammatory interleukin (IL)-1β, IL-6, and IL-13, and increased anti-inflammatory IL-10 synthesis, while DPP4 inhibitors sitagliptin and vildagliptin increased proinflammatory cytokine production, indicating an enhanced risk of RA development. The evidence suggests that increasing DPP4 expression is a novel strategy for RA disease.

The CXC chemokine ligand‐13 (CXCL13) is a chemoattractant of B cells and has been implicated in the progression of many cancers. So far, CXCL13 and its related receptor CXCR5 have been proved to regulate cancer cell migration as well as tumour metastasis. However, the role of CXCL13‐CXCR5 axis in metastasis of lung cancer is still poorly understood. In this study, we found that CXCL13 and CXCR5 were commonly up‐regulated in lung cancer specimens compared with normal tissues among different cohorts. Our evidence showed that CXCL13 obviously promoted migration of lung cancer cells, and this effect was mediated by vascular cell adhesion molecule‐1 (VCAM‐1) expression. We also confirmed that CXCR5, the major receptor responsible for CXCL13 function, was required for CXCL13‐promoted cell migration. We also test the candidate components which are activated after CXCL13 treatment and found that phospholipase C‐β (PLCβ), protein kinase C‐α (PKCα) and c‐Src signalling pathways were involved in CXCL13‐promoted cell migration and VCAM‐1 expression in lung cancer cells. Finally, CXCL13 stimulated NF‐κB transcription factor in lung cancer cells, contributing to VCAM‐1 expression in translational level. These evidences propose a novel insight into lung cancer metastasis which is regulated by CXCL13.

Alzheimer’s disease (AD) is a neurodegenerative disease that usually affects older individuals. Owing to the higher incidence of root caries and missing teeth in elderly individuals, the bacteria involved in these dental concerns might potentially deteriorate their cognitive function. Altered microbiota in the oral cavity may induce neuroinflammation through migration from the oral cavity to the brain. However, the correlation between the composition of the oral microbiota and neurodegenerative disease remains unclear. In this study, we evaluated sequence to determine the relative abundance and diversity of bacterial taxa in the dental plaque of elderly patients with AD and controls. Oral samples, the DMFT index, and other clinical examination data were collected from 17 patients with AD and 18 normal elderly individuals as the control group. Patients with AD had significantly more missing teeth and higher dental plaque weight but lower microbial diversity than controls. Significantly increased numbers of Lactobacillales, Streptococcaceae, and Firmicutes/Bacteroidetes and a significantly decreased number of Fusobacterium were observed in patients with AD. In conclusion, using the PacBio single-molecule real-time (SMRT) sequencing platform to survey the microbiota dysbiosis biomarkers in the oral cavity of elderly individuals could serve as a tool to identify patients with AD.

A major number of studies have demonstrated Beta-tricalcium phosphate (β-TCP) biocompatibility, bioactivity, and osteoconductivity characteristics in bone regeneration. The aim of this research was to enhance β-TCP's biocompatibility, and evaluate its physicochemical properties by argon glow discharge plasma (GDP) plasma surface treatment without modifying its surface. Treated β-TCP was analyzed by scanning electron microscopy (SEM), energy-dispersive spectrometry, X-ray photoelectron spectroscopy (XPS), X-ray diffraction analysis, and Fourier transform infrared spectroscopy characterization. To evaluate treated β-TCP biocompatibility and osteoblastic differentiation, water-soluble tetrazolium salts-1 (WST-1), immunofluorescence, alkaline phosphatase (ALP) assay, and quantitative real-time polymerase chain reaction (QPCR) were done using human mesenchymal stem cells (hMSCs). The results indicated a slight enhancement of the β-TCP by GDP sputtering, which resulted in a higher Ca/P ratio (2.05) than the control. Furthermore, when compared with control β-TCP, we observed an improvement of WST-1 on all days (p p p

OBJECTIVES The effect of toothbrushing on the color, relative translucency, and surface roughness of extrinsically stained zirconia dental restorations is still unclear. The purpose of the present study was to evaluate the optical properties and surface textures of extrinsically stained or glazed partially stabilized zirconia with 5 mol% yttria (5Y-PSZ) after toothbrushing by determining changes in the color, translucency parameter (TP), and surface roughness. MATERIALS AND METHODS Specimens (2 mm thick; n = 50) were sectioned from 5Y-PSZ blanks. Three brands of powdered stains (namely VI, SH, IV) and a glaze (GL) were used to extrinsically stain the specimen surfaces (n = 10 per group). The specimens were subjected to 10,000-50,000 simulated toothbrushing strokes using a toothpaste slurry (Ora2 PREMIUM Stain clear paste). The color parameters were measured before staining or glazing and before and after simulated brushing. The color changes and TP values can be calculated before and after simulated brushing. The surface roughness was also evaluated. RESULTS Significant changes were found in the shade and TP values of 5Y-PSZ after extrinsic staining, but no significant changes were found after toothbrushing, irrespective of the staining brand (p > 0.05). The surface roughness of the characterized 5Y-PSZ specimens decreased after toothbrushing, whereas that of the non-characterized 5Y-PSZ group increased. CONCLUSIONS Toothbrushing markedly affects the surface roughness of extrinsically stained or glazed 5Y-PSZ specimens, whereas no impacts on the color or translucency were observed. CLINICAL RELEVANCE For esthetic reasons, clinicians and dental technicians prefer to apply extrinsic stains to zirconia restorations, which profoundly affects its appearance. The limited influence of toothbrushing on color and translucency of 5Y-PSZ is promising for clinical applications.

Aims Insulin-like growth factor (IGF) signaling has been documented in several human malignancies and is thought to contribute to cellular differentiation and migration, as well as malignant progression. A major binding molecule of IGF, IGF-binding protein 3 (IGFBP-3), regulates multiple IGF effects. Here, we focused on the effect of IGFBP-3 in the motility of osteosarcoma cells and examined signaling regulation. Materials and methods Using a human osteosarcoma tissue array, immunohistochemical staining determined levels of IGFBP-3 expression in osteosarcoma tissue and in normal tissue. The wound healing migration assay, Transwell migration assay, luciferase reporter assay, immunofluorescence staining, Western blot and real-time quantitative PCR were performed to examine whether IGFBP-3 facilitates VCAM-1-dependent migration of osteosarcoma cells. Key findings In this study, we found significantly higher IGFBP-3 levels in osteosarcoma tissue compared with normal healthy tissue. IGFBP-3 treatment of two human osteosarcoma cell lines promoted cell migration and upregulated levels of VCAM-1 expression via PI3K/Akt and AP-1 signaling. Significance IGFBP-3 appears to be a novel therapeutic target in metastatic osteosarcoma.

Mineral trioxide aggregate (MTA) is widely used in various dental endodontic applications such as root-end filling, furcal perforation repair, and vital pulp therapy. In spite of many attempts to improve handling properties and reduce the discoloration of MTA, the ideal root canal filling material has yet to be fully developed. The objective of this study was to investigate the setting time, mechanical properties, and biocompatibility of MTA set by a silk fibroin solution. A 5 wt% silk fibroin (SF) solution (a novel hydration accelerant) was used to set SavDen&reg, MTA and ProRoot&reg, white MTA (WMTA). Changes in setting time, diametral tensile strength (DTS), material crystallization, in vitro cell viability, and cell morphology were assessed by Vicat needle measurement, a universal testing machine, scanning electron microscopy (SEM), and WST-1 assay, respectively. The initial setting time of ProRoot&reg, MTA and SavDen&reg, MTA experienced a drastic decrease of 83.9% and 42.1% when deionized water was replaced by 5 wt% SF solution as the liquid phase. The DTS of SavDen&reg, MTA showed a significant increase after set by the SF solution in 24 h. A human osteoblast-like cell (MG-63)-based WST-1 assay revealed that both ProRoot&reg, MTA hydrated using SF solution did not significantly differ (p &gt, 0.05) in cell viability. MG-63 cells with pseudopodia attachments and nuclear protrusions represent a healthier and more adherent status on the surface of MTA when set with SF solution. The results suggest that the 5 wt% SF solution may be used as an alternative hydration accelerant for MTA in endodontic applications.

This study evaluated color stability and staining susceptibility of five direct resin-based composites (RBCs) subjected to light-activated in-office bleaching with 40% hydrogen peroxide (HP). The test materials included 5 RBCs, which consisted of one nano-filled, one sub-micron, one bulk-filled, and two nano-hybrid RBC types. Ten disc-shaped specimens of each RBC were fabricated and divided into bleaching (BLE) and non-bleaching (CON) groups (n = 5 for each group). Specimens were then immersed in red wine solution over 4 h. A spectrophotometer was used to obtain Commission Internationale de l’Eclairage (CIE) L*a*b* parameters for each of the following periods tested: before bleaching (TBA), after bleaching (TBL), and after staining (TST). Color stability and staining susceptibility were evaluated using two metrics, CIEDE2000 color differences (ΔE00) and whiteness variations using the whiteness index (ΔWID). Data were analyzed using repeated measures two-way analysis of variance (ANOVA) (α = 0.05). Statistically significant and clinically unaccepted ΔE00 and ΔWID were observed for all tested specimens between TBA and TBL. The nano-hybrid type RBCs showed the highest discoloration among materials after bleaching treatment. The BLE group exhibited significantly higher ΔE00 and ΔWID than the CON group for all the tested RBCs between TBA and TST. The sub-micron type RBC showed the highest discoloration among materials after immersion in the red wine. Conclusion. The light-activated in-office bleaching with 40% HP’s influences on color and whiteness index were material-dependent. The use of bleaching treatment also increased the susceptibility to red wine for all RBCs.

Absorbable porcine collagen membrane with a bovine bone graft can be considered for regenerative treatment in periodontal class II furcation defects. We evaluated the clinical efficacy of guided tissue regeneration (GTR) treatment with bovine bone xenograft and a porcine collagen membrane in molars with class II furcations. Probing depth (PD), clinical attachment level (CAL), and bone level (BL) were recorded at baseline and at 3, 6, and 9 months postoperatively. Thirty class II furcation defects from the lower and upper molars were assessed. Significant improvements in PD and CAL were observed from baseline to 9 months in all groups (p &lt, 0.01). BL improved in all groups except group A in the upper molars in radiographic assessment (p &lt, 0.05). The lower and upper molars showed PD reduction of 50.5% ± 7.44% and 46.2% ± 11.2%, respectively, at 9 months (p = 0.044). In furcations of 1–3 mm, the lower and upper molars showed PD reductions of 51.2% ± 4.49% and 36.5% ± 16.14%, respectively (p = 0.035). The lower and upper molars showed a CAL gain of 51.1% ± 4.64% and 33.6% ± 18.8%, respectively (p = 0.037). Thus, GTR with bovine bone graft and porcine collagen membrane yielded good results in class II furcations, with better results in the lower than in the upper molars.

Background: Candida albicans, a common fungal pathogen that can cause opportunistic infections, is regarded as an apparently asexual, diploid fungus. A parasexual cycle was previously found between homozygotes with opposite mating type-like loci (MTLa/α). Fluconazole-resistant strains had a higher proportion of MTL homozygotes, whereas MTL homozygous C. albicans was found in only about 3.2% of clinical strains. MTL heterozygotes had a low frequency (1.4 Ã 10â4) of whiteâopaque switching to MTL homozygotes in nature. Methods: Here, a reference C. albicans strain (SC5314) was used in a fluconazole-induced assay to obtain standard opaque MTL homozygous strains and first-generation daughter strains from the fluconazole inhibition zone. Further separation methods were employed to produce second- and third-generation daughter strains. Polymerase chain reaction analysis based on MTL genes was used to define MTL genotypes, and microscopic observations, a flow-cytometric assay, and an antifungal E-test were used to compare microbiological characteristics. Results: MTL homozygotes were found at a high frequency (17 of 35; 48.6%) in fluconazole-induced first-generation daughter strains, as were morphological polymorphisms, decreased DNA content, and modified antifungal drug susceptibility. High-frequency MTL homozygosity was identified inside the fluconazole inhibition zone within 24 hours. The DNA content of fluconazole-induced daughter strains was reduced compared with their progenitor SC5314 and standard MTL homozygous strains. Conclusion: Treatment with fluconazole, commonly used to treat invasive candidiasis, inhibited the growth of C. albicans and altered its microbiological characteristics. Our results suggest that fluconazole treatment induces the high frequency of loss of heterozygosity and microbiological polymorphism in C. albicans. Keywords: Candida albicans, fluconazole, loss of heterozygosity, mating type-like gene

As peri-implantitis is associated with biofilm development, the characteristics of titanium implants may influence biofilm formation, and thereby increase the risk for inflammation. The objective of this study was to evaluate the effect of titanium surface roughness induced by various debridement methods of peri-implants, such as the use of an ultrasonic scaler, rubber polishing cup, gallium–aluminum–arsenide laser, and chlorhexidine (CHX) rinse, on Porphyromonas (P.) gingivalis. Surface debridement was performed by immersing titanium discs in CHX rinse for 24 h or treatment with a laser, polishing cup, or ultrasonic scaler for 60 s. Surface topography was examined using a profilometer. For the bacterial assay, specimens were inoculated with P. gingivalis for 2 h and incubated for 6, 12, and 24 h. After incubation, bacterial adhesion on the discs was quantified via spectrophotometric evaluation. Moreover, scanning electron microscopy (SEM) images were analyzed to quantify P. gingivalis colonization on the titanium surfaces. Data were analyzed using one-way analysis of variance and Pearson’s correlation test (p

Selective laser melting (SLM) is extensively used for fabricating metallic biomedical products. After 3D printing, it is almost always advisable to apply a heat treatment to release the internal tensions or optimize the mechanical properties of the printed parts. The aim of this paper is to investigate the effects of heat treatment of SLM printed Ti-6Al-4V (Ti64) circular specimens on the areal surface texture parameters and cell attachment. Areal surface texture parameters, including the arithmetic mean height (Sa), root-mean-square height (Sq), skewness (Ssk), and kurtosis (Sku) were characterized. In addition, wavelet-based multi-resolution analysis was applied to investigate the characteristic length scales of untreated and heat-treated Ti64 specimens. In this study, the vertical distance between the highest and lowest position of cell attachment for each sampling area was defined as DH. Results showed that an increase in the periodic characteristic length scale was primarily due to the formation of large-scale aggregations of Ti64 metal powder particles on the heat-treated surface. In addition, MG-63 cells preferred lying in concave hollows, in heat-treated specimens, values of DH statistically significantly decreased from 31.6 ± 4.2 to 8.8 ± 2.8 μm, while Sku decreased from 3.3 ± 1.4 to 2.6 ± 0.6, indicating a strong influence of Sku on cell attachment.

Statement of problem The esthetic appearance of anatomic-contour zirconia restorations is influenced by the shade of the coloring liquid and the optical properties of the luting cements. However, few studies are available on the effects of surface-finishing methods and luting cements on colored anatomic-contour zirconia restorations. Purpose The purpose of this in vitro study was to investigate the effects of surface finishing methods on the color distribution of colored anatomic-contour zirconia crowns before and after being cemented onto abutments. Material and methods Implant-supported anatomic-contour zirconia premolar crowns were fabricated and immersed in A3-coloring liquid for 30 seconds. The colored zirconia crowns were separated into 3 groups according to the method of surface treatment: no treatment (N), polishing (P), and glazing (G). The zirconia crowns without coloring liquid application served as the control group. CIELab color coordinates were obtained, and color differences (ΔE) between shaded crowns were calculated with a spectrophotometer. The color stability of the crown before and after cement application was also investigated. Results Before cement application, the mean color difference between groups N and P was 2.85 ΔE units, whereas the mean ΔE value between groups N and G was 3.27. Mean ΔE values with and without cement application among groups ranged from 2.75 to 3.45 ΔE units. Conclusions The color appearance of the colored zirconia crowns was strongly influenced by the surface-finishing methods and luting cement application.

Bone regeneration procedures require alternative graft biomaterials to those for autogenous bone. Therefore, we developed a novel porcine graft using particle sizes of 250–500 μm and 500–1000 μm in rabbit calvarial bone defects and compared the graft properties with those of commercial hydroxyapatite (HA)/beta-tricalcium phosphate (β-TCP) over eight weeks. Surgery was performed in 20 adult male New Zealand white rabbits. During a standardized surgical procedure, four calvarial critical-size defects of 5 mm diameter and 3 mm depth were prepared. The defects were filled with HA/β-TCP, 250–500 μm or 500–1000 μm porcine graft, and control defects were not filled. The animals were grouped for sacrifice at 1, 2, 4, and 8 weeks post-surgery. Subsequently, sample blocks were prepared for micro-computed tomography (micro-CT) scanning and histological sectioning. Similar bone formations were observed in all three treatment groups, although the 250–500 μm porcine graft performed slightly better. Rabbit calvarial bone tissue positively responded to porcine grafts and commercial HA/β-TCP, structural analyses showed similar crystallinity and porosity of the porcine and HA/β-TCP grafts, which facilitated bone formation through osteoconduction. These porcine grafts can be considered as graft substitutes, although further development is required for clinical applications.

The aim of the study was to investigate the efficacy of the addition of funoran to xylitol chewing gum in dental plaque. In a double-blinded randomized controlled clinical trial, 36 health adults (21–30 years old), who volunteered after informed consent, with >105 colony-forming units/ml mutans streptococci (MS) at baseline, were assigned randomly into one of three parallel study groups: xylitol+funoran gum (group A), sucrose gum group (group B), and control group (no gum have been provided; group C). The pH value, flash weight, and MS of dental plaque were recorded at baseline and after 2 weeks of treatment. A statistically significant reduction (p

In the present study, a nanoporous, biocompatible titanium dioxide (TiO2) film was formed on the surface of titanium, using oxygen plasma immersion ion implantation (OPIII), and the influence of this film on the bio-functionalization, including the proliferation and differentiation properties of MG-63 osteoblast-like cells, was analyzed and investigated. The OPIII-treated surface was characterized by X-ray photoelectron, which showed that a TiOx layer was formed on Ti substrates. This TiOx surface exhibited nanoscale surface roughness in the form of nanoporous structures. The results also revealed that MG-63 cells expressed increased proliferation on the OPIII-treated surface as compared with the untreated Ti substrate. The Ti specimens treated with plasma energy of 1 kW revealed better expression of alkaline phosphatase (ALP) activity and showed higher average surface roughness than untreated specimens. Thus, it can be concluded that bioactivity of Ti implants can potentially be improved by OPIII.

Background The surface properties of Ti–6Al–4V (Ti64) alloys extensively affect the biological responses in a physical environment. To enhance the surface biocompatibility of Ti64 specimens, in the present study, electrical discharge machining (EDM) was performed to produce the modified layer on the surface of the Ti64 specimen. Methods The EDM-functionalized surfaces were obtained at three different pulse durations, which varied from 10 μs to 60 μs. The surface properties of the EDM-functionalized specimen were characterized with scanning electron microscopy and X-ray photoelectron spectroscopy. The properties of adhesion and proliferation of MG-63 cells were evaluated for the interactions between the EDM-functionalized layer and cells. Results The incorporation of oxygen roughened the EDM-functionalized surface on a microscale, where the nanoscale pores were superimposed. The EDM-functionalized layer, which can generate the thick anatase TiO 2 on the Ti64 surface, afforded a cytocompatible environment. In cell culture, alkaline phosphatase activity could be enhanced on the EDM-functionalized surfaces as compared to the untreated surface. In addition, the increase in pulse durations to the EDM functionalization led to the enhancement of multiple osteoblast functions. Conclusion The present study revealed that the chemistry and crystallinity of the EDM-functionalized layer played important roles in affecting osteoblastic responses to the specimens, thereby providing insight into the development of new biomedical implant surfaces.

Periodontitis (PD) is an inflammatory disease characterized by gingival inflammation and resorption of alveolar bone. Impaired receptor activator of nuclear factor-kappa B ligand/osteoprotegerin (RANKL/OPG) signaling caused by enhanced production of pro-inflammatory cytokines plays an essential role in the pathogenesis of PD. Considering melatonin possesses significant anti-inflammatory property, this study aimed to determine whether prophylactic treatment with melatonin would effectively normalize RANKL/OPG signaling, depress toll-like receptor 4/myeloid differentiation factor 88 (TLR4/MyD88)-mediated pro-inflammatory cytokine activation, and successfully suppress the pathogenesis of PD. PD was induced in adult rats by placing the ligature at molar subgingival regions. Fourteen days before PD induction, 10, 50, or 100 mg/kg of melatonin was intraperitoneally injected for consecutive 28 days. Biochemical and enzyme-linked immunosorbent assay were used to detect TLR4/MyD88 activity, RANKL, OPG, interleukin 1β, interleukin 6, and tumor necrosis factor-α levels, respectively. The extent of bone loss, bone mineral intensity, and calcium intensity was further evaluated by scanning electron microscopy, micro-computed tomography, and energy-dispersive X-ray spectroscopy. Results indicated that high RANKL/OPG ratio, TLR4/MyD88 activity, and pro-inflammatory cytokine levels were detected following PD. Impaired biochemical findings paralleled well with severe bone loss and reduced calcium intensity. However, in rats pretreated with melatonin, all above parameters were successfully returned to nearly normal levels with maximal change observed in rats receiving 100 mg/kg. As prophylactic treatment with melatonin effectively normalizes RANKL/OPG signaling by depressing TLR4/MyD88-mediated pro-inflammatory cytokine production, dietary supplement with melatonin may serve as an advanced strategy to strengthen oral health to counteract PD-induced destructive damage.

BACKGROUND:Glow discharge plasma (GDP) procedure is an effective method for grafting various proteins, including albumin, type I collagen, and fibronectin, onto a titanium surface. However, the behavior and impact of titanium (Ti) surface modification is yet to be unraveled. PURPOSE:The purpose of this study is to evaluate and analyze the biological properties of fibronectin-grafted Ti surfaces treated by GDP. MATERIALS AND METHODS:Grade II Ti discs were initially cleaned and autoclaved to obtain original specimens. Subsequently, the specimens were GDP treated and grafted with fibronectin to form Ar-GDP (Argon GDP treatment only) and GDP-fib (fibronectin coating following GDP treatment) groups. Blood coagulation test and MG-63 cell culture were performed to evaluate the biological effects on the specimen. RESULTS:There was no significant difference between Ar-GDP and GDP-fib groups in blood compatibility analysis. While in the MTT test, cellular proliferation was benefited from the presence of fibronectin coating. The numbers of cells on Ar-GDP and GDP-fib specimens were greater than those in the original specimens after 24 h of culturing. CONCLUSIONS:GDP treatment combined with fibronectin grafting favored MG-63 cell adhesion, migration, and proliferation on titanium surfaces, which could be attributed to the improved surface properties.

AIM: Our goal was to investigate the relationship between clinical status and the presence of carious or periodontal pathogens among parent-child familial pairs. Clinical practices of risk assessment with consideration of familial pathogen interaction might reduce the need for therapy, improve patient outcomes, and ultimately reduce oral disease burden. MATERIALS AND METHODS: In this study, we enrolled 30 parent-child pairs, with the children exhibiting complete deciduous dentition or mixed dentition with only permanent first molars. Clinical statuses were evaluated using caries and periodontal disease indicators, including the sum of decay and the number of missing or filled teeth (DMFT) for adults, decay, extraction caused by dental disease, and filled teeth (deft), for children, probing depth, and plaque control record (PCR). Supra- and sub-gingival bacteria were determined based on semi-quantitative measurements of microbial infection by using data from the Dentocult(®) SM test (caries-related organisms) and the PerioCheck(®) test (periodontal disease-related organisms). RESULTS: No statistically significant relationship was detected between the prevalence of periodontal pathogens and that of cariogenic pathogens in the oral cavity. However, the clinical status of caries (DMFT) was negatively correlated with the clinical status of periodontal disease (pocket depth) in parents who were infected with dominant periodontal pathogens (r = -0.59, p

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