Controlled, prospective, randomized, clinical split-mouth evaluation of partial ceramic crowns luted with a new, universal adhesive system/resin cement: results after 18 months.

OBJECTIVES A new universal adhesive with corresponding luting composite was recently marketed which can be used both, in a self-etch or in an etch-and-rinse mode. In this study, the clinical performance of partial ceramic crowns (PCCs) inserted with this adhesive and the corresponding luting material used in a self-etch or selective etch approach was compared with a self-adhesive universal luting material. MATERIAL AND METHODS Three PCCs were placed in a split-mouth design in 50 patients. Two PCCs were luted with a combination of a universal adhesive/resin cement (Scotchbond Universal/RelyX Ultimate, 3M ESPE) with (SB+E)/without (SB-E) selective enamel etching. Another PCC was luted with a self-adhesive resin cement (RelyX Unicem 2, 3M ESPE). Forty-eight patients were evaluated clinically according to FDI criteria at baseline and 6, 12 and 18 months. For statistical analyses, the chi-square test (α = 0.05) and Kaplan-Meier analysis were applied. RESULTS Clinically, no statistically significant differences between groups were detected over time. Within groups, clinically significant increase for criterion "marginal staining" was detected for SB-E over 18 months. Kaplan-Meier analysis revealed significantly higher retention rates for SB+E (97.8 %) and SB-E (95.6 %) in comparison to RXU2 (75.6 %). CONCLUSION The 18-month clinical performance of a new universal adhesive/composite combination showed no differences with respect to bonding strategy and may be recommended for luting PCCs. Longer-term evaluation is needed to confirm superiority of SB+E over SB-E. CLINICAL RELEVANCE At 18 months, the new multi-mode adhesive, Scotchbond Universal, showed clinically reliable results when used for luting PCCs

General diseases and medications in 687 patients reporting on adverse effects from dental materials.

OBJECTIVES Examination of patients claiming adverse effects from dental materials can be very challenging. Particularly, systemic aspects must be considered besides dental and orofacial diseases and allergies. Therefore, the aim of this study was to investigate a cohort of 687 patients reporting on adverse effects from dental materials focusing on findings related to known general diseases or conditions or medication-related findings with relevance to their subjective complaints. METHODS Six hundred eighty-seven patients visiting a specialized consultation on claimed adverse effects from dental materials were retrospectively investigated for their subjective complaints, findings related to known general diseases or conditions, medication-related findings, dental and orofacial findings, or allergies with relevance to their subjective complaints. RESULTS The most frequent subjective complaints were burning mouth (44.1%), taste disorders (28.5%), and dry mouth (23.7%). In 58.4% of the patients, dental and orofacial findings relevant to their complaints could be found. Findings related to known general diseases or conditions or medication-related findings were found in 28.7% or 21.0% of the patients, respectively. Regarding medications, findings related to antihypertensives (10.0%) and psychotropic drugs (5.7%) were found most frequently. Relevant diagnosed allergies toward dental materials were found in 11.9%, hyposalivation in 9.6% of the patients. In 15.1% of the patients, no objectifiable causes for the expressed complaints could be found. CONCLUSIONS For patients complaining of adverse effects from dental materials, findings related to known general diseases or conditions and medications should be given particular consideration, while still in some patients, no objectifiable causes for their complaints can be found. CLINICAL RELEVANCE For patients complaining about adverse effects from dental materials, specialized consultations and close collaboration with experts from other medical fields are eligible

Molecular magnetic resonance imaging (MRI) of inflamed myocardium using ferucarbotran in patients with acute myocardial infarction

Introduction: Superparamagnetic iron oxide nanoparticle (SPIO)-based molecular imaging agents targeting macrophages have been developed and successfully applied in animal models of myocardial infarction

Remineralizing amorphous calcium phosphate based composite resins: the influence of inert fillers on monomer conversion, polymerization shrinkage, and microhardness

AIM: To determine if the addition of inert fillers to a bioactive dental restorative composite material affects its degree of conversion (DC), polymerization shrinkage (PS), and microhardness (HV). METHODS: Three amorphous calcium phosphate (ACP)-based composite resins: without added fillers (0-ACP), with 10% of barium-glass fillers (Ba-ACP), and with 10% of silica fillers (Si-ACP), as well as commercial control (Ceram•X, Dentsply DeTrey) were tested in laboratory conditions. The amount of ACP (40%) and the composition of the resin mixture (based on ethoxylated bisphenol A dimethacrylate) was the same for all ACP materials. Fourier transform infrared spectroscopy was used to determine the DC (n = 40), 20 min and 72 h after polymerization. Linear PS and Vickers microhardness (n = 40) were also evaluated. The results were analyzed by paired samples t test, ANOVA, and one-way repeated measures ANOVA with Student-Newman-Keuls or Tukey’s post-hoc test (P = 0.05). RESULTS: The addition of barium fillers significantly increased the DC (20 min) (75.84 ± 0.62%) in comparison to 0-ACP (73.92 ± 3.08%), but the addition of silica fillers lowered the DC (71.00 ± 0.57%). Ceram•X had the lowest DC (54.93 ± 1.00%) and linear PS (1.01 ± 0.24%) but the highest HV (20.73 ± 2.09). PS was significantly reduced (P < 0.010) in both Ba-ACP (1.13 ± 0.25%) and Si-ACP (1.17 ± 0.19%) compared to 0-ACP (1.43 ± 0.21%). HV was significantly higher in Si-ACP (12.82 ± 1.30) than in 0-ACP (10.54 ± 0.86) and Ba-ACP (10.75 ± 0.62) (P < 0.010). CONCLUSION: Incorporation of inert fillers to bioactive remineralizing composites enhanced their physical-mechanical performance in laboratory conditions. Both added fillers reduced the PS while maintaining high levels of the DC. Silica fillers additionally moderately improved the HV of ACP composites

Three-Dimensional Human Cell Cultures for Cytotoxicity Testing of Dental Filling Materials

Cilj: Za uzgoj trodimenzionalnih kultura stanica radi testiranja citotoksičnosti stomatoloških materijala u testu dentinske barijere (DBT) dosad su se rabile “besmrtne” stanice goveđe pulpe. U ovom istraživanju ocijenili smo uporabu stanica dobivenih iz ljudske pulpe koje bi mogle preciznije simulirati kliničku situaciju. Također, testirali smo smolasti kompozitni materijal. Materijali i metode: SV40-transfektirane stanice ljudske pulpe (tHPC) uzgojene su u hidrogelu (fibrin, peptid, kolagen) te su određena mehanička svojstva i vitalnost stanica (MTT I WST-1). Na uzorcima stanica uzgojenih u kolagenu proveden je test proliferacije stanica nakon četiri tjedna (WST-1). Nakon 14 dana na uzgojenim trodimenzionalnim kulturama stanica u kolagenu proveden je DBT test s 200 μm debelim dentinskim diskovima. Nakon inkubacije od 24 sata pod perfuzijom (0.3ml/h) upotrijebljeni su materijali prema uputama proizvođača (1) President (Coltene): negativna (netoksična) kontrola, (2) CaGPG14 (ISO 7405): pozitivna (toksična) kontrola, (3) Tetric EvoCeram (Ivoclar Viadent) s Clearfil SEBond (Kuraray, referentni materijal), (4) N´Durance (Sepodont, testni materijal), (5) N´Durance s Clearfil SEBond. Ocijenjena je vitalnost stanica nakon inkubacije od 24 sata (WST-1). Izračunat je postotak relativne vitalnosti (negativna kontrola = 100%) i provedena je statistička analiza (Kruskal-Wallisov test, p<0.05). Rezultati: Hidrogelovi od fibrina i peptida pokazali su nedostatna mehanička svojstva za DBT. Kolagenski gel pokazao se pogodnim za trodimenzionalnu kulturu stanica tHCP do 21 dan. Nakon toga uzorci su preneseni na DBT analizu te su rezultati bili slični onima iz prijašnjih istraživanja s goveđim stanicama. DBT test, primjenjujući tHPC, u kolagenu nije pokazivao statistički značajne razlike između testiranih materijala s adhezivom i bez njega i referentnih smolastih kompozita. Zaključak: tHCP u kolagenu može nadomjestiti goveđe stanice u DBT testu. Testirani materijal ne uzrokuje oštećenje pulpe ako je prekrivena intaktnim slojem dentina.Objectives: So far, bovine immortalized pulp cells have been used as three dimensional cultures for cytotoxicity testing of filling materials in the dentin barrier test (DBT). In this study, the use of human pulp-derived cells was evaluated, which would better simulate the clinical situation, and a composite material with a new resin base was tested. Materials and Methods: SV40-transfected human pulp cells (tHPC) were cultured in hydrogels (fibrin, peptide, collagen) and mechanical properties and cell viability (MTT or WST-1) were determined. For cell cultures in collagen, a four week - proliferation assay was performed (WST-1). After 14 days of three-dimensional culture in collagen, tHPC were introduced into the DBT with 200 μm dentin disks. After a 24-hour incubation under perfusion (0.3 ml/h), the following materials were applied according to the manufacturers’ instructions (1) President (Coltene): negative (non-toxic) control, (2) CaGPG14 (ISO 7405): positive (toxic) control, (3) Tetric EvoCeram (Ivoclar Vivadent) with Clearfil SEBond (Kuraray, reference material), (4) N´Durance (Sepodont, test material), (5) N´Durance with Clearfil SEBond. Cell viability was determined after 24-hour incubation (WST-1). The percentage of relative viability was calculated (negative control=100%) and statistically analyzed (Kruskal-Wallis-test, p<0.05). Results: Fibrin and peptide gels had insufficient mechanical properties for the DBT. Collagen appeared suitable for three-dimensional cell culture of tHPC for up to 21 days. The cultures could be transferred to the DBT device and results for controls were similar to previous tests with bovine cells. The DBT using tHPC in the collagen showed no statistically significant difference between the test material with and without the adhesive and the reference resin composite. Conclusions: tHPC in collagen can replace bovine cells in the DBT. The tested filling material is not likely to cause pulp damage, if the pulp is covered by an intact dentin layer

Antibacterial efficacy of cold atmospheric plasma against Enterococcus faecalis planktonic cultures and biofilms in vitro

Nosocomial infections have become a serious threat in our times and are getting more difficult to handle due to increasing development of resistances in bacteria. In this light, cold atmospheric plasma (CAP), which is known to effectively inactivate microorganisms, may be a promising alternative for application in the fields of dentistry and dermatology. CAPs are partly ionised gases, which operate at low temperature and are composed of electrons, ions, excited atoms and molecules, reactive oxygen and nitrogen species. In this study, the effect of CAP generated from ambient air was investigated against Enterococcus faecalis, grown on agar plates or as biofilms cultured for up to 72 h. CAP reduced the colony forming units (CFU) on agar plates by > 7 log10 steps. Treatment of 24 h old biofilms of E. faecalis resulted in CFU-reductions by ≥ 3 log10 steps after CAP treatment for 5 min and by ≥ 5 log10 steps after CAP treatment for 10 min. In biofilm experiments, chlorhexidine (CHX) and UVC radiation served as positive controls and were only slightly more effective than CAP. There was no damage of cytoplasmic membranes upon CAP treatment as shown by spectrometric measurements for release of nucleic acids. Thus, membrane damage seems not to be the primary mechanism of action for CAP towards E. faecalis. Overall, CAP showed pronounced antimicrobial efficacy against E. faecalis on agar plates as well as in biofilms similar to positive controls CHX or UVC

Membrane damage as mechanism of photodynamic inactivation using Methylene blue and TMPyP in Escherichia coli and Staphylococcus aureus

The worldwide threat of antibiotic resistance requires alternative strategies to fight bacterial infections. A promising approach to support conventional antibiotic therapy is the antimicrobial photodynamic inactivation (aPDI). The aim of this work was to show further insights into the antimicrobial photodynamic principle using two photosensitizers (PS) of different chemical classes, Methylene Blue (MB) and TMPyP, and the organisms Escherichia coli and Staphylococcus aureus as Gram-negative and Gram-positive representatives. Planktonic cultures of both species were cultured under aerobic conditions for 24 h followed by treatment with MB or TMPyP at various concentrations for an incubation period of 10 min and subsequent irradiation for 10 min. Ability to replicate was evaluated by CFU assay. Accumulation of PS was measured using a spectrophotometer. The cytoplasmic membrane integrity was investigated by flow cytometry using SYBR Green and propidium iodide. In experiments on the replication ability of bacteria after photodynamic treatment with TMPyP or MB, a killing rate of 5 log10 steps of the bacteria was achieved. Concentration-dependent accumulation of both PS was shown by spectrophotometric measurements whereby a higher accumulation of TMPyP and less accumulation of MB was found for S. aureus as compared to E. coli. For the first time, a membrane-damaging effect of TMPyP and MB in both bacterial strains could be shown using flow cytometry analyses. Furthermore, we found that reduction of the replication ability occurs with lower concentrations than needed for membrane damage upon MB suggesting that membrane damage is not the only mechanism of aPDI using MB