Since tooth loss is a common problem in humans and is widespread worldwide, dental implants are an effective and optimal alternative to solve this problem. Thus, it is necessary to develop implants with improved surfaces that favor the osseointegration of the implant into the surrounding tissues and promote cell adhesion and proliferation while also preventing and inhibiting peri-implant infections that can lead to implant failure. In this regard, this review aims to provide new insights into nanotechnology and the use of nanoparticles in creating new coatings, the new trends for enhancing dental implant surfaces, and the current technologies used for this purpose. Although in vitro and in vivo tests attest to the possible use of the nanomaterials described in this review, further tests are needed to establish the optimal concentrations to be safe for clinical trials.
The purpose of this study is to identify the stress levels that act in inlay and onlay restorations, according to the direction and value of the external force applied. The study was conducted using the Finite Element Method (FEM) of three types of ceramics: pressed lithium disilicate and monolith, zirconia, and three different adhesive systems: self-adhesive, universal, and dual-cure cements. In addition to FEM, the inlay/onlay-dental structure interface analysis was performed by means of Scanning Electron Microscopy (SEM). The geometric models were reconstructed based on computer tomography images of an undamaged molar followed by geometrical procedures of inducing the inlay and onlay reconstructions. The two functional models were then simulated for different orientations of external force and different material properties, according to the considered adhesives and ceramics. The Scanning Electron Microscopy (SEM) was conducted on 30 extracted teeth, divided into three groups according to the adhesive cement type. Both FEM simulation and SEM investigations reveal very good mechanical behavior of the adhesive-dental structure and adhesive-ceramic interfaces for inlay and onlay reconstructions. All results lead to the conclusion that a physiological mastication force applied, regardless of direction, cannot produce a mechanical failure of either inlay or onlay reconstructions. The adhesive bond between the restorations and the dental structure can stabilize the ceramic restorations, resulting in a higher strength to the action of external forces.
Infections continue to pose significant challenges in dentistry, necessitating the development of innovative solutions that can effectively address these issues. This study focuses on creating coatings made from polymethyl methacrylate (PMMA) enriched with zinc oxide–silver composite nanoparticles, layered to Ti6Al4V–titanium alloy substrates. The application of these materials aims to create a solution for the abutments utilized in complete dental implant systems, representing the area most susceptible to bacterial infections. The nanoparticles were synthesized using a hydrothermal method, optimized through specific temperature and pressure parameters to achieve effective morphologies and sizes that enhance antibacterial efficacy. The layers were applied to the titanium substrate using the spin coating technique, chosen for its advantages and compatibility with the materials involved. Comprehensive analyses were conducted on the antimicrobial powders, including X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Furthermore, the PMMA-based coatings incorporating antimicrobial nanoparticles were evaluated to ensure uniformity and homogeneity across the titanium alloy surface by IR mapping and SBF immersion–SEM analysis. The antimicrobial activity of the samples was demonstrated with impressive results against Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans, as assessed through biofilm modulation studies. The biocompatibility of the samples was validated through in vitro cell-based assays, which demonstrated excellent compatibility between PMMA-based coatings and human preosteoblasts, confirming their potential suitability for future use in dental implants.
Background/Objectives: Titanium dental implants are considered to be the most modern and effective solution for replacing lost teeth. These medical devices not only restore the chewing and aesthetic functionality of the smile but also provide a stable support for crowns, bridges or dentures. The aim of this study was to identify the perceptions of patients about titanium dental implants and their effects on the human body. Methods: A structural equation model (SEM) was conducted to study how a series of independent variables have the ability to influence the perception and intention of the patients regarding these medical devices. A data analysis was performed using WarpPLS 8.0 software. This research was conducted on a sample of 162 respondents. Results: The results illustrated that patients’ perception of titanium dental implants is explained by 71% of the independent variables analysed, and their intention to have a new implant in the next period is explained by 61%. The proposed econometric model was validated, with seven hypotheses accepted out of nine. Conclusions: Although titanium has long been used in implant dentistry, in recent years, experts have identified a number of adverse effects that can arise from its use. This study has added value both at the practical and theoretical level. Perception is influenced by respondents’ perceived advantages, by the problems perceived by the respondents regarding titanium dental implants, by the degree of awareness of the risks of titanium dental implants, and by the adverse effects experienced by respondents regarding titanium dental implants.
The purpose of this paper is to compare the fracture behavior of interfaces obtained using fourth-generation and universal dental adhesives. The study relies on optic and SEM to evaluate the dentin–adhesive–restoration material interface of the samples and also on FEA simulation of fracture behavior. Specimen fabrication relied on 20 extracted teeth, in which class I cavities were created according to a protocol established based on the rules of minimally invasive therapy. For the direct adhesive technique, the adhesives used were: three-step All Bond, three-batch A and one-step Clearfil Universal Bond Quick-batch B. The restoration was performed with the same composite for both adhesives: Gradia direct posterior. The simulation used a 3D reconstructed molar on which geometric operations were performed to obtain an assembly that replicated a physical specimen. Material properties were applied to each component based on the information found in the literature. A simplified model for crack propagation was constructed, and using the fracture mechanics tool in Ansys 2019, the stress intensity factors that act at the crack tip of the adhesive interface were obtained. Mechanical simulation and microscopic investigation showed us how the interface of the dentine–adhesive–filling material performed in cases of both dental adhesives and for a certain loading condition. Important differences were identified among the adhesives, the fourth generation being superior to the fourth generation especially due to the separate steps in which the tooth surface was prepared for adhesion.
This study investigates the synthesis of Zn2SnO4@SiO2@5-FU nanoparticles as an additive for bone fillers in dental maxillofacial reconstruction. Zn2SnO4 nanoparticles were synthesized and coated with a SiO2 shell, followed by the incorporation of 5-Fluorouracil (5-FU), aimed at enhancing the therapeutic properties of classical fillers. Structural analysis using X-ray diffraction confirmed that Zn2SnO4 was the single crystalline phase present, with its crystallinity preserved after both SiO2 coating and 5-FU incorporation. SEM characterization revealed the micro-spherical particles of Zn2SnO4 assembled by an agglomeration of nanorods, exhibiting dimensions and morphological characteristics that were consistent after the addition of both the SiO2 shell and 5-FU. Fourier-transformed infrared spectroscopy provided solid proof of the successful synthesis of Zn2SnO4, Zn2SnO4@SiO2, and Zn2SnO4@SiO2@5-FU, confirming the presence of expected functional groups. The SiO2 layer improved nanoparticle stability in the solution, as indicated by zeta potential measurements, while adding 5-FU significantly increased biocompatibility and targeting efficiency. The existence of the SiO2 shell and 5-FU is also confirmed by the hydrodynamic diameter, indicating an increase in particle size after incorporating both compounds. Antibacterial assays demonstrated a selective efficacy against Gram-positive bacteria, with Zn2SnO4@SiO2@5-FU showing the strongest inhibitory effects. Biofilm inhibition studies further confirmed the nanoparticles’ effectiveness in preventing bacterial colonization. Cytotoxicity tests on the A-431 human epidermoid carcinoma cell line revealed a dose-dependent reduction in cell viability, highlighting the potential of 5-FU for targeted cancer treatment. These findings highlight the potential of Zn2SnO4@SiO2@5-FU nanoparticles as a multifunctional additive for bone fillers, offering enhanced antimicrobial and antitumor capabilities.