Objectives: Using dental Ti implants has become a well-accepted and used method for replacing missing dentition. It has become evident that in many cases peri-implant inflammation develops. The objective was to create and evaluate the antibacterial effect of silver nanoparticle (Ag-NP) coated Ti surfaces that can help to prevent such processes if applied on the surface of dental implants. Methods: Annealing I, Ag ion implantation by the beam of an Electron Cyclotron Resonance Ion Source (ECRIS), Ag Physical Vapor Deposition (PVD), Annealing II procedures were used, respectively, to create a safely anchored Ag-NP layer on 1x1 cm^2, Grade 2 titanium samples. The antibacterial effect was evaluated by culturing Staphylococcus aureus (ATCC 29213) on the surfaces of the samples for 8 hours, and comparing the results to that of glass as control and of pure titanium samples. Alamar Blue assay was carried out to check cytotoxicity. Results: It was proved that silver nanoparticles were present on the treated surfaces. The average diameter of the particles was 58 nm, with a 25 nm deviation and Gaussian distribution, the the filling factor was 25%. Antibacterial evaluation revealed that the nanoparticle covered samples had an antibacterial effect of 64.6% that was statistically significant. Tests also proved that the nanoparticles are safely anchored to the titanium surface and are not cytotoxic. Conclusion: Creating a silver nanoparticle layer can be an option to add antibacterial features to the implant surface and to help in the prevention of peri-implant inflammatory processes. Recent studies demonstrated that silver nanoparticles can induce pathology in mammal cells, thus safe fixation of the particles is essential to prevent them from getting into the circulation.

In this study, scaffolds were prepared via an electrospinning method for application in oral cavities. The hydrophilicity of the fiber mesh is of paramount importance, as it promotes cell spreading; however, the most commonly used polyvinyl alcohol (PVA) and other hydrophilic fiber meshes immediately disintegrate in aqueous media. In contrast, the excessive hydrophobicity of the scaffolds already inhibits cells adhesion on the surface. Therefore, the hydrophilicity of the fiber meshes needed to be optimized. Scaffolds with different polyvinyl alcohol (PVA)/chitosan/citric acid ratios were prepared. The addition of chitosan and the heat initiated cross-linkage of the polymers via citric acid enhanced the scaffolds’ hydrophobicity. The optimization of this property could be followed by contact angle measurements, and the increased number of cross-linkages were also supported by IR spectroscopy results. The fibers’ physical parameters were monitored via low-vacuum scanning electron microscopy (SEM) and atomic force microscopy (AFM). As biocompatibility is essential for dental applications, Alamar Blue assay was used to prove that meshes do not have any negative effects on dental pulp stem cells. Our results showed that the optimization of the fiber nets was successful, as they will not disintegrate in intraoral cavities during dental applications.

Bone morphogenetic protein 2 (BMP-2) is a member of the transforming growth factor-β superfamily, it is known to be a factor involved in skeletal development and capable of inducing in vitro osteogenic differentiation of mesenchymal stem cells (MSCs). Dental pulp stem cells (DPSCs) isolated from extracted third molar teeth are an ideal resource for bone tissue engineering and regeneration applications, due to their convenient isolation, safe cryopreservation, and easy maintenance in cell cultures. The aims of this study were to deliver BMP-2 under control of the tetracycline-inducible (tet-on) promoter into dental pulp stem cells and to examine whether these BMP-2 expressing cell lines are capable of promoting osteogenic differentiation in vitro. BMP-2 gene was cloned into the lentiviral transfer plasmid pTet-IRES-EGFP and used to establish the DPSC-BMP-2 cell line. DPSC, DPSC-GFP (mock) and DPSC-BMP-2 cell lines were cultured in growth medium or osteogenic medium in the presence or absence of 100 ng/ml doxycycline. To assess differentiation, alkaline phosphatase activity, calcium accumulation and gene transcription levels of different genes involved in osteogenic differentiation (BMP-2, Runx2, alkaline phosphatase, and noggin) were measured. Doxycycline-induced BMP-2 expression induced the differentiation of DPSCs into the preosteoblastic stage but could not favor the further maturation into osteoblasts and osteocytes. We found that while Runx2 gene transcription was continuously upregulated in doxycycline-treated DPSC-BMP-2 cells, the alkaline phosphatase activity and the accumulation of minerals were reduced. As a result of the increased BMP-2 expression, the transcription level of the BMP antagonist noggin was also upregulated, and probably caused the observed effects regarding alkaline phosphatase (ALP) activity and mineral deposition. Our study shows that this system is effective in controlling transgene expression in DPSC cell line. Exploration of all known factors affecting osteogenic differentiation and their interactions is of major importance for the field of regenerative medicine. As the metabolic reaction to the upregulated transgene transcription appears to be cell line-specific, a wrongly selected target gene and/or regulation system could have adverse effects on differentiation.

Aspects of oral health related quality of life (OHRQoL) attracted an increased attention recently. The aim of the study was to assess self-reported oral health related quality of life (OHRQoL) among patients requiring prosthetic rehabilitation and to determine the rate of improvement 1 month and 6–12 months after therapy. In addition, effect of age, gender, oral health indicators and denture types before treatment were assessed on OHRQoL as evaluated and reported by the patients. Hungarian version of OHIP-49 (OHIP-49-H) questionnaire was completed before oral rehabilitation (T0-phase) by 389 patients undergoing prosthetic replacement. After 1 month (T1-phase) and 6–12 months (T2-phase) recall periods 235 and 92 patients completed the questionnaire. The median interquartile range (IQR) values of the total OHIP-49-H score were calculated for T0-, T1- and T2-phases. Reliability of the questionnaire was checked by Cronbach’s statistics. Age, gender, oral health indicators and denture types of patients before and after treatment were recorded and treatment-associated changes in OHRQoL were evaluated. The study demonstrated the excellent reliability and internal consistency of OHIP-49-H by a high and narrow range of Cronbach’s alpha value (0.81-0.93). A median OHIP-49-H score of 52; IQR = 25-83 demonstrated a poor OHRQoL on first admission. Decreasing median total OHIP-49-H scores 1 month (24; IQR = 9-51; p < 0.001) and 6–12 months (20; IQR = 7-37; p = 0,055) after therapy indicated an improvement of OHRQoL. Patients’ age and CPI value assessed before treatment proved to be significant factors of OHRQoL. Here we presented representative data about self-assessed OHRQoL of patients requiring prosthetic treatment from Hungary using OHIP-49-H questionnaire. The results demonstrated that the restoration of oral health was associated with an improvement in patients’ OHRQoL. According to the demographical and T0 phase clinical status, the treatment was more effective in the respect of OHIP-49-H score improvement among females (than among males), among younger (than among more aged), and among patients with more serious CPI assessed at T0. The type of prosthetic interventions did not exert a significant effect on total OHIP-49-H score, suggesting that the improvement in OHRQoL is independent from the type of denture applied.