The aim of the systematic review was to analyze the use of mesenchymal stem cells (MSC) and biomaterial for periodontal regeneration from preclinical animal models and human. Electronic databases were searched and additional hand-search in leading journals was performed. The research strategy was achieved according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The including criteria were as follows: MSC, biomaterial, in vivo studies, with histologic and radiologic analysis and written in English. The risk of bias was assessed for individual studies. A total of 50 articles were selected and investigated in the systematic review. These results indicate that MSC and scaffold provide beneficial effects on periodontal regeneration, with no adverse effects of such interventions. Future studies need to identify the suitable association of MSC and biomaterial and to characterize the type of new cementum and the organization of the periodontal ligament fiber regeneration.

This study investigated the role played by different pH environments in the deterioration of bonds between Y-TZP and Ti-6Al-4V. One hundred and thirty-five specimens were randomly assigned to one of the following storage media at 37°C: (1) distilled water, pH 6.9, DW; (2) acidic solution, pH 1–2, CS; and (3) alkaline solution, pH 10–11, KS. Shear bond strength (SBS) tests were carried out at the 4-, 14-, and 30-day storage time intervals. The morphology characteristics and elements distribution of the fracture surfaces were analyzed. CS-30 showed the lowest mean SBS and the least amount of residual cement on the Ti-6Al-4V surface after the SBS tests. Bond strength tended to decrease with increasing storage time for the acidic group. Alkaline and neutral media showed little influence on the SBS of Y-TZP to Ti-6Al-4V in 30 days. Acidic environments should be properly avoided to obtain reliable long-term bonding strength between Ti-6Al-4V and Y-TZP.

The purpose was to evaluate the effect of a hydrophilic amide monomer on μTBS of one-step adhesive to dentin at different application times. Clearfil Universal Bond Quick (UBQ), experimental adhesive (UBQ_exp; same compositions as UBQ but hydrophilic amide monomer was replaced with 2-hydroxyethyl methacrylate), Clearfil SE ONE and Clearfil SE Bond were applied to midcoronal dentin prepared with 600-grit SiC at different application time (0, 10, 20 and 40 s). Water sorption (Wsp) and the ultimate tensile strength (UTS) of polymerized adhesives were also measured. UBQ showed significantly lower Wsp and higher UTS than UBQ_exp. At each application time, UBQ exhibited significantly higher μTBSs than UBQ_exp. UBQ showed the highest μTBS at 0 s application time among all the adhesives. When the application time was prolonged from 0 s to 10 s, only UBQ showed no significant difference. The hydrophilic amide monomer increased μTBS with reduction in Wsp and increase in the UTS and may allow a shortened application time.

Forming models and brazing parts, both of which require high accuracy, are greatly affected the polymerization shrinkage of pattern resin. In 2018, a lower-shrinkage autopolymerizing pattern resin (PRK) was introduced. In this work, we compared the rate of polymerization shrinkage between PRK with that of three autopolymerizing resins —GC Pattern Resin (GPR), Pi-Ku Plast (PIK), and Fixpeed (FIX)— as controls. The shrinkage percentages at 10 min were 7.26±0.88 for PRK, 10.78±2.28 for GPR, 8.03±1.08% for PIK, and 7.46±1.25 for FIX. The shrinkage of PRK was significantly lower than that of GPR. The lower-shrinkage autopolymerizing resin contains some multifunctional monomer and indicated that the amount of monomer was accordingly reduced from the result of polymer size and abundance ratio. Our results suggested that the monomer component and the polymer particle size were factors that contribute to reducing contraction of the resins.

Corrosion of metallic materials in the oral cavity could trigger metal allergy in patients. To clarify the risk elevation of magnetic fields (MFs) exposure on metallic corrosion when combined with fluoride-containing dental care products and indigenous oral bacteria, we investigated electric toothbrush-derived MF-induced corrosion of orthodontic stainless steel (SUS) and nickel titanium (Ni-Ti) wires in the presence of fluoride and oral bacteria, i.e. Streptococcus (S) mutans and S. sanguinis. MFs induced an electric current in the wires under both environments. Oral bacteria corroded SUS wires, and fluoride corroded SUS and Ni-Ti wires as previously reported; however, no additive or synergistic effects of MF exposure on fluoride- and microbiologically-induced metallic corrosion were observed. These results suggest that the MFs from electric toothbrushes do not increase the risk of corrosion of metallic appliances, given that the oral environment of patients is exposed to oral bacteria and fluoride-containing products.

The purpose of this study was to assess the effect of pre-etching time and material on shear bond strength (SBS) of self-adhesive resin cements to eroded and sound enamel. Eroded enamel specimens were assigned into 5 groups (n=20 each) based on enamel surface treatment as follow: Group N, eroded enamel (without surface pre-treatment); Group PH15, 35% H₃PO₄ etching for 15 s; Group PH30, 35% H₃PO₄ etching for 30 s; Group L30, 20% lactic acid etching for 30 s and Group L60, 20% lactic acid etching for 60 s.Composite blocks were fabricated and cemented to enamel surfaces with one of two self-adhesive cements. Notched-edge SBS was assessed. Bond strength of self-adhesive cement to eroded enamel surface significantly enhanced following application of 20% lactic acid for 30 s.

The aim of this in vitro study was to explore light transmission through an individually formed fiber-reinforced composite (FRC) post compared with two prefabricated FRC posts. Three different glass FRC posts from different manufacturers were used: two groups included prefabricated glass FRC posts (RelyX and GC Fiber Posts) and one group consisted of individually formed E-glass FRC posts with semi-interpenetrating polymer network (semi-IPN) polymer matrix (everStick Post). Various lengths of posts and lightprotected cylinders were made. The specimens were light-polymerized on the test tray of a light radiance testing device (MARC Resin Calibrator). Light transmission in the direction of fibers was registered. Light transmission decreased with increasing post length (p≤0.001; ANOVA) up to 12 mm in all post groups. The individually formed FRC post showed highest light transmission in all cylinder lengths (p<0.001) compared to prefabricated FRC posts, which could benefit polymerization of post material and luting cement.

Endogenous dentinal matrix metalloproteinases (MMPs) have been implicated in the auto-degradation of collagen fibrils within resin infiltrated layers of dentinal attachment. In order to target these proteinases, we must know which MMPs are produced and activated at the resin/dentin interface. In this study, we have optimized an extraction procedure and quantitated levels of endogenous MMPs in samples of dentin removed from the cavity walls of a single, extracted tooth. In our tooth-cavity model, an occlusal cavity (2×4×2 mm) was prepared and removed from the tooth crown, leaving surrounding dentinal walls of 1-mm-thick. The samples were pulverized with an analytic mill. Using enzyme-linked immunosorbent assay (ELISA), an average of 34.7 picograms of MMP-9 was detected in less than 300 mg of dentinal powder. This is the first study of its kind to quantitate endogenous levels of MMP in dentinal protein isolated from the cavity walls of a single, extracted tooth.

This study compared the effect of a novel zinc containing, Caredyne Shield (CS), and a fluoroaluminocalciumsilicate-based, Nanoseal (NS) desensitizers on dentin tubule occlusion, inhibition of Streptococcus mutans (S. mutans) biofilm growth, and resistance to bacterial demineralization. Desensitizers were applied to simulated hypersensitive bovine dentin, with distilled water used as a control. S. mutans biofilms were grown on the surface of each specimen in an oral biofilm simulator. CS showed the least bacterial count and water insoluble glucan amount followed by NS. Transverse micro radiography revealed that both CS and NS showed significant reduction in mineral loss and lesion depth of the associated lesion. Scanning electron micrographs showed that the two desensitizers formed obvious depositions on the dentin surfaces, occlusion of tubules and mineral tag formation.

The purpose of this study was to investigate the effects of curing mode with a high-power LED curing unit (VALO) in terms of microtensile bond strength (μTBS) to dentin and microhardness of two dual-cure resin cements. Panavia V5 (V5) and Rely X Ultimate (RXU) were polymerized using one of three curing modes with VALO or self-cure mode to bond a CAD/CAM resin block to a flat dentin surface. Specimens were sectioned and subjected to μTBS test. Vickers hardness values of V5 and RXU were also measured. Two-way ANOVA indicated curing mode and resin cement affected μTBS. For self-cure mode, V5 had significantly higher μTBS than RXU (p<0.05). Higher irradiance did not always provide higher μTBS of dual-cure resin cement to dentin. One-way ANOVA indicated the curing modes affected microhardness of each cement. As for microhardness of RXU, there were significant differences between selfcure mode and light cure modes (p<0.05).

The purpose of this study was to investigate combinations of resin coating materials with a dual-cure resin cement for indirect restorations by evaluating microtensile bond strengths (μTBS). Dentin surfaces of human molars were bonded with either a direct or an indirect resin composite with/without the resin coating technique. For the resin coating material, Clearfil SE Bond 2 and either one of Clearfil Protect Liner F, Clearfil Majesty LV, Panavia V5 or an experimental light-cure coating material were used. For the dual-cure resin cement, either Panavia V5 or Panavia F2.0 were used with Panavia V5 Tooth Primer or ED Primer II. Resin coating does not always contribute to the enhancement of μTBS. The highest μTBS was obtained with the resin coating combination of Clearfil SE Bond 2 and Panavia V5, and cementation with Panavia F2.0, which was identical to that of the direct resin composite bonded with Clearfil SE Bond 2.

The aim of this study was to investigate the effects of artificial saliva on permeability measured using a highly sensitive digital flow meter of dentin discs treated with a phosphate containing desensitizer compound (Teethmate desensitizer; TD). Four random groups (n=10) were treated either with TD or distilled water (DW), then stored in artificial saliva (AS) or DW for 1 day, 1 week and 1 month. Flow rates under 2 kPa pressure were calculated as percentage reduction (PR%) from the baseline. The PR% of TD/AS group was significantly lower after 1 day and 1 week, but the PR%s of 1 month groups among TD/AS, TD/DW and DW/AS were not significantly different. The SEM photograph of TD/AS group displayed that the dentin surface was densely covered with mineral deposits. Ca and phosphate ions from the artificial saliva could penetrate into the tubules and precipitate as hydroxyapatite, resulting in the reduction in permeability.

This study examined the influences of clinical application of immediate dentin sealing (IDS) and temporary restoration (TR) on prepared abutment surfaces on the bonding of computer-aided design/computer-aided manufacturing (CAD/CAM) ceramic crown restorations after cyclic loading. Standardized abutments were prepared in 60 human mandibular premolars. Dentin surfaces of half of the specimens were sealed with adhesive and flowable composite, while those of the other half were not sealed. A half of both sealed and non-sealed specimens were restored using a temporary cement and temporary crown. Each individual CAD/CAM ceramic crown was fabricated and cemented to an individual abutment. The restored specimens were subjected to cyclic loading, and the micro tensile bond strengths (μ-TBS) were measured. IDS contributed to an increase in the bond strength, whereas TR did not affect the bond strength. IDS restoration without TR yielded the maximum bond reliability in achieve specific μ-TBS values for the restoration and ensuring durability against debonding.

Prostheses and implants have been widely utilized in the orthopedic and dental fields. Nowadays, significant advances have been made in the structural and functional connection between living bone and prostheses, especially in the presence of compromised bone quantity/quality. Despite improvement in the treatment outcomes after augmentation, there are still challenges to meet the clinical demands due to limited materials available. In the current study, we investigated the effects of nano-nacre particles as an alternative material on stimulating bone cell differentiation and formation. Mouse osteoblastic cells (MC3T3-E1) were cultured on nano-nacre/type I collagen composite scaffold (NN-ICS) and type I collagen scaffold (ICS). Generated nano-nacre particles showed controlled release of protein and calcium for a period of 36 days. NN-ICS significantly contributed to the proliferation and differentiation of preosteoblasts compared to ICS controls. Our data showed that nano-nacre particles could serve as a candidate of bone substitution material, which potentially contributed to treatment outcomes in cases with compromised bone quality and/or quality.

The aim of the study was to assess the effect of staining and bleaching on CAD/CAM materials with high (HT) and low translucency (LT or T). Samples were stored in coffee and subsequently bleached. CIELAB parameters were recorded at baseline, after coffee immersion, after bleaching. Translucency parameter (TP), whiteness index (WID) and color changes were calculated (ΔE₀₀). Influence of staining and bleaching was analyzed with repeated-measures ANOVA and color differences between materials were analyzed with one-way ANOVA (α=0.05). Staining and bleaching significantly affected CIELAB parameters and WID for all materials (p<0.001). TP was significantly influenced by staining and bleaching for Crios and Enamic (p<0.05). Mean color differences were significantly different between materials (p<0.001). The greatest color changes due to staining were observed for Lava Ultimate while the lowest for e.max CAD. Both coffee staining and bleaching induced greater color changes for HT materials of the same brand compared to LT.

We evaluated the influence of the composition and powder/water (P/W) ratio of powder-type denture adhesives (DA) based on sodium carboxymethyl cellulose (CMC-Na) and poly(methyl vinyl ether-maleic anhydride) (PVM-MA) on the strength of adhesion to acrylic resin and initial viscosity. Twenty types of DA were prepared by mixing CMC-Na and PVM-MA at various weight ratios with distilled water in P/W ratios ranging from 0.125 to 0.500. Adhesion strength and viscosity were measured using a universal testing machine and a controlled-stress rheometer, respectively. A higher percentage of CMC-Na and higher P/W ratios resulted in higher adhesion strength and viscosity. The effect of the CMC-Na/PVM-MA weight ratio on adhesion strength and viscosity was larger than that of the P/W ratio. DA with higher viscosity had higher adhesion strength. These results suggest that the adhesion strength and initial viscosity of powder-type DA can be controlled via the P/W ratio and the CMC-Na/PVM-MA weight ratio.

This study evaluated the effect of material type, thickness and composite-composite interfacial adhesion on the load-bearing capacity of the bilayered composite structures. Bilayered cylindrical specimens (diameter=7 mm, height=5 mm) were prepared having three surface-layer thicknesses (1, 1.5, 2 mm) of Gænial Posterior to overlay base-composites [everX Posterior or Smart Dentin Replacement (SDR)]. Adhesion between surface and base composite-layers was based on an O₂-inhibited layer for optimal-adhesion (OA) or polished surface for deteriorated-adhesion (DA). Specimens (n=10) were light-cured before static-loading with a steel-ball until fracture. Stress distribution in the same designs of mechanical test was calculated by finite element analysis (FEA). Static-loading demonstrated that in both base materials, thickness and adhesion had an effect on load-bearing capacity (p<0.05). FEA showed less strain distribution for everX groups than SDR.With OA, everX Posterior demonstrated higher load-bearing capacity even with thin surface-composite layer. DA made the load-bearing capacity more sensitive to surface-layer thickness.

The paper aimed to compare the performance of artificial neural network (ANN) model with the results of in vitro experiments. For these experiments, maxillary molars of four different denture teeth were subjected to tea, coffee, cola, cherry juice, distilled water. Vickers microhardness and surface roughness values were measured. Subsequently, ANN model for the prediction of microhardness and surface roughness of different denture teeth were examined. A back-propagation ANN has been used to develop a model relating to the amount of microhardness and surface roughness. The independent variables of the model are distilled water, tea, filtered coffee, cola, cherry juice, time and denture teeth. Microhardness and surface roughness were chosen as the dependent variables. According to the results, a neural network architecture having one input layer with ten neurons, two hidden layers with six neurons, one output layer with two neurons and an epoch size of 48 gives better prediction. Prediction models for dental materials could also be supportive for in vitro studies.

The goal of this study was to examine the effect of thermal cycling on the amount of monomer released from bulk fill composites. Five bulk fill composite resins were used in the study. Extraction solutions were obtained at the end of the time/thermal cycle periods: 0–1 day/0–1,500, 1–3 days/1,500–4,500 and 3–7 days/4,500–10,000. The monomers in the extractions samples taken at each time point were measured on an HPLC instrument. The obtained data were analyzed by repeated measures of variance analysis and tukey multiple comparison tests (p<0.05). The thermocycling increased the amount of monomer released from all composites at 0–1 day (p<0.05). At 0–1 and 1–3 days, Venus Bulk Fill and Filtek Bulk Fill composite resins were more affected. Polymer networks with high molecular weight monomers such as Bis-GMA and UDMA can be less affected by thermal changes compared to polymers with low molecular weight monomers.

The aim of this study was to improve the cytocompatibility and differentiation of human bone marrow-derived mesenchymal stem cells on the surface of titanium implants by immobilizing biofunctional molecules on their surface. Gly-Arg-Gly-Asp-Ser (GRGDS) peptides, human plasma fibronectin (pFN), or type I collagen from calf skin (Col) was covalently immobilized on the titanium surfaces. Twice as many cells attached to the Col- and pFN-immobilized titanium surfaces than attached to the as-polished surface control. The ALP activity of the cells, as well as the mineralized nodule formation, was significantly higher on the Col- and pFN-immobilized titanium surfaces than on the as-polished surfaces. These results indicate that the immobilization of biofunctional molecules such as Col and pFN on titanium surfaces enhances the attachment, spreading, proliferation, and differentiation of human bone marrow-derived mesenchymal stem cells, which may lead to a more rapid bone-titanium integration.

Fluoride varnish is a professionally applied product that prevents dental caries. However, fluoride varnishes do not provide sustained fluoride release. The objective of this study was to prepare fluoride varnish formulations containing various amounts of chitosan that would generate sustained fluoride release. We evaluated their chemical structure, viscosity, and in vitro fluoride release. Furthermore, the 3-(4, 5-dimethylthiazolyl-2)-2,5diphenyltetrazolium bromide (MTT) assay and direct contact test were used to determine varnish cytotoxicity. We found that all fluoride varnish formulations had the same chemical structure. Their viscosity demonstrated a chitosan concentration-dependent increase. In vitro fluoride release showed a sustained fluoride release. The chitosan fluoride varnishes were cytotoxic to human gingival fibroblasts. We propose the new fluoride varnish formulation as a potential material to be used as a sustained release fluoride varnish.

The aim of this study was to investigate the effect of microslits formed by Nd:YVO₄ laser beam machining on the bond strength between two types of zirconia, yttria-partially stabilized zirconia (Y-TZP) and ceria-partially stabilized zirconia/alumina nanocomposite (Ce-TZP/A), and porcelain or two types of resin. Zirconia disks were divided into three groups: 1) non-treated (NT); 2) blasted with alumina particles (AB); 3) microslits fabricated on a zirconia surface by laser beam machining (MS). After veneering porcelain or resins on zirconia specimens, halves of the resin specimens were thermocycled up to 20,000 cycles. The shear bond strength between porcelain and both types of zirconia was not improved by the microslits. Before and after thermocycling, the bond strength between an indirect composite resin or acrylic resin and Y-TZP with microslits was the highest. It was concluded that the microslits on Y-TZP enabled micromechanical interlocking and improved the bond strength and durability of the resins.