Although implants have undergone a remarkable development over the past decades, modern implants still show complications that make the improvement of materials necessary. The presented study investigates the load-bearing capacity of an experimental dental implant made of a niobium alloy (Nb1Zr) compared to identical implants made of Ti6Al4V using chewing simulation for artificial aging. Eight implants each with an experimental design were manufactured from Nb1Zr and Ti6Al4V.
View Article and Find Full Text PDFJ Mech Behav Biomed Mater
December 2024
Currently, the restoration of missing teeth by means of dental implants is a common treatment method in dentistry. Ensuring optimal contact between teeth (occlusion) when designing the occlusal surface of an implant-supported crown is crucial for the patient. Although there are various occlusal concepts and guidelines for achieving optimised occlusion, adapting an occlusal surface is challenging.
View Article and Find Full Text PDFBiofilm-associated peri-implant infections pose a major problem in modern medicine. The understanding of biofilm development is hampered by biofilm complexity and the lack of robust clinical models. This study comprehensively characterized the dynamics of early biofilm formation in the transmucosal passage of implant abutments in 12 patients.
View Article and Find Full Text PDFThe colonization of dental implants by oral biofilms causes inflammatory reactions that can ultimately lead to implant loss. Therefore, safety-integrated implant surfaces are under development that aim to detect bacterial attachment at an early stage and subsequently release antibacterial compounds to prevent their accumulation. Since primary oral colonizers ferment carbohydrates leading to local acidification, pH is considered a promising trigger for these surfaces.
View Article and Find Full Text PDFThe formation of pathogenic multispecies biofilms in the human oral cavity can lead to implant-associated infections, which may ultimately result in implant failure. These infections are neither easily detected nor readily treated. Due to high complexity of oral biofilms, detailed mechanisms of the bacterial dysbiotic shift are not yet even fully understood.
View Article and Find Full Text PDFPurpose: Studies about success of FPDs (fixed partial dentures) mostly include restorations built by different clinicians. This results in limited comparability of the data. The aim of this study was to evaluate complications of all-ceramic FPDs built by 1 dentist between 2011 to 2023.
View Article and Find Full Text PDFBacterial infection is a major challenge to human health. Although various potent antibiotics have emerged in recent decades, current challenges arise from the increasing number of multi-drug-resistant species. Infections associated with implants represent a particular challenge because they are usually diagnosed at an advanced stage and are difficult to treat with antibiotics owing to the formation of protective biofilms.
View Article and Find Full Text PDFJ Mater Sci Mater Med
October 2024
This study aimed to investigate adhesive shear bond strength (SBS) on an ultrafine-grained niobium alloy (UFG-Nb) that is a potential dental implant material. SBS of three adhesive systems combined with three composites to UFG-Nb was compared to corresponding SBS to Ti-6Al-4V and to zirconia. Specimens of the substrates UFG-Nb, Ti-6Al-4V and zirconia with plane surfaces were sandblasted with AlO, cleaned and dried.
View Article and Find Full Text PDFStatement Of Problem: The hydrophobic and bioinert nature of polyetheretherketone (PEEK) implants needs to be addressed for successful osseointegration.
Purpose: The purpose of this in vitro study was to evaluate the osteoblast cell behavior on PEEK implant surfaces treated with airborne-particle abrasion using different grit size aluminum oxide (AlO) particles.
Material And Methods: Disk-shaped specimens (n=96) were prepared from medical grade PEEK rods and were distributed into 4 groups (n=24) of untreated PEEK (PEEK 0), airborne-particle abrasion using 50-μm AlO particles (PEEK 50), airborne-particle abrasion using 110-μm AlO particles (PEEK 110), and airborne-particle abrasion using 150-μm AlO particles (PEEK 150).
Additive manufacturing enables local grading of the stiffness of dental implants through targeted adjustment of the manufacturing parameters to meet patient specific requirements. The extent to which such a manufacturing approach affects the interaction between the implant body and the surrounding bone, and what grading is optimal, is currently insufficiently investigated. This study investigates the effect of different Young's modulus grading approaches on stresses in the peri-implant bone via finite element analysis.
View Article and Find Full Text PDFDue to the high incidence of implant failures, dual functionalization of titanium surfaces with antibacterial and osteogenic agents, like silver (Ag) and strontium (Sr), has gained significant attention in recent years. However, so far, the combined antibacterial and osteoinductive effectiveness of Ag/Sr-based titanium surface coatings has only been analyzed in individual studies. This systematic review aims to evaluate the existing scientific literature regarding the PICOS question "Does dual incorporation of strontium/silver enhances the osteogenic and anti-bacterial characteristics of Ti surfaces ?".
View Article and Find Full Text PDFEarly detection of specific oral bacterial species would enable timely treatment and prevention of certain oral diseases. In this work, we investigated the sensitivity and specificity of functionalized gold nanoparticles for plasmonic sensing of oral bacteria. This approach is based on the aggregation of positively charged gold nanoparticles on the negatively charged bacteria surface and the corresponding localized surface plasmon resonance (LSPR) shift.
View Article and Find Full Text PDFPurpose: Acidification by bacterial biofilms at the bracket/tooth interface is one of the most common problems in fixed orthodontic treatments, which can lead to white spot lesions (WSL) and caries. As lingual brackets were shown to exhibit reduced WSL formation clinically, the aim of this in situ study was to compare initial intraoral biofilm formation and acidification on bracket-like specimens placed buccally and palatally in the upper jaw as a possible cause for this observation.
Methods: Intraoral biofilm was collected from splints equipped with buccally and palatally exposed test specimens, which were worn by 12 volunteers for a total of 48 h.
Staphylococcus aureus biofilm-associated infections are a common complication in modern medicine. Due to inherent resilience of biofilms to antibiotics and the rising number of antibiotic-resistant bacterial strains, new treatment options are required. For this purpose, ultrapure, spherical silver-gold-alloy nanoparticles with homogenous elemental distribution were synthesized by laser ablation in liquids and analyzed for their antibacterial activity on different stages of S.
View Article and Find Full Text PDFActivist groups attack animal research and put scientists and their institutions under pressure, whereas scientists often remain silent. We report an interdisciplinary research project driven by a communication science perspective on how citizens respond to news reports about animal research (3 experiments, overall N = 765) and a German science-initiated information platform ("Tierversuche verstehen"; controlled user study, N = 100). Findings demonstrate that a critical journalist perspective within neutral, two-sided news reports (e.
View Article and Find Full Text PDFFront Bioeng Biotechnol
October 2023
Type I interferon-beta (IFN-β) is a crucial component of innate and adaptive immune systems inside the host. The formation of bacterial biofilms on medical implants can lead to inflammatory diseases and implant failure. Biofilms elicit IFN-β production inside the host that, in turn, restrict bacterial growth.
View Article and Find Full Text PDFObjectives: The aim of the present study was to assess the long-term course of OHRQoL and the impact of the loading protocol in patients receiving a single mandibular implant supporting a complete denture over a period of five years.
Methods: In this multicenter RCT, a total of 158 edentulous patients were initially included and were randomly allocated immediately after placement of a mandibular midline implant to either immediate loading (IL) or to conventional loading (CL) with submerged healing. The assessment of OHRQoL was performed with the 49-item Oral Health Impact Profile (OHIP) at baseline and 1, 4, 12, 24, and 60 months after loading.
The bactericidal effects of silver nanoparticles (Ag NPs) against infectious strains of multiresistant bacteria is a well-studied phenomenon, highly relevant for many researchers and clinicians battling bacterial infections. However, little is known about the uptake of the Ag NPs into the bacteria, the related uptake mechanisms, and how they are connected to antimicrobial activity. Even less information is available on AgAu alloy NPs uptake.
View Article and Find Full Text PDFThis paper deals with the mathematical modeling of bacterial co-aggregation and its numerical implementation in a FEM framework. Since the concept of co-aggregation refers to the physical binding between cells of different microbial species, a system composed of two species is considered in the modeling framework. The extension of the model to an arbitrary number of species is straightforward.
View Article and Find Full Text PDFAim: New technologies such as tactile robots and artificial intelligence (AI) are finding their way into clinical practice in dentistry and could contribute to the improvement of oral health care in the future. The hypothesis of the present in vitro pilot study trial was that a collaborative tactile robot programmed by a dental student could remove interproximal artificial plaque as effectively as a human operator.
Materials And Methods: Model teeth were fully covered with artificial plaque and set into phantom jaws.
Objectives: This systematic review aimed to evaluate the efficacy of supportive care provision, frequency and protocol in patients treated for peri-implantitis, as reported in prospective and retrospective studies of at least 3-years duration.
Materials And Methods: A systematic search of three electronic databases was undertaken up to 21 July 2022 and supplemented by hand-search to identify studies that included participants treated for peri-implantitis and followed for at least 3 years. Owing to high heterogeneity, a meta-analysis was not appropriate, and therefore, data and risk of bias were explored qualitatively.
Int J Environ Res Public Health
March 2023
Children's sedentary time has increased, while daily physical activity and motor performance have decreased. We evaluated an integrated school-based exercise program by assessing changes in motor skills after one year and comparing these changes to children who did not participate. We included 303 children from five schools in this longitudinal study and assigned them either to the exercise group (EG; n = 183 with daily exercise program) or the waiting group (WG; n = 120).
View Article and Find Full Text PDFComput Methods Biomech Biomed Engin
April 2024
In finite element analysis bone is often treated as two-layered material that has a discontinuity between the cortical and cancellous bone, which leads to a singularity and incorrect stresses. The goal of this study was to eliminate this singularity and to create a more realistic representation of bone which also considers the transition zone between cortical and cancellous bone as observed in natural bone. This was achieved by modelling bone as a graded material and inserting node-specific values for Young's modulus in the finite element simulation, whereas the transition zone thickness was derived from a CT scan.
View Article and Find Full Text PDFThe severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has created a public crisis. Many medical and public institutions and businesses went into isolation in response to the pandemic. Because SARS-CoV-2 can spread irrespective of a patient's course of disease, these institutions' continued operation or reopening based on the assessment and control of virus spread can be supported by targeted population screening.
View Article and Find Full Text PDFThe aim of this study was to determine the effect of sandblasting, grinding and plasma treatment on the adhesive bond strength between framework ceramic (Y-TZP) and veneering ceramic (feldspar ceramic). Therefore, four-point bending specimens (n = 180) were cut from densely sintered 3Y-TZP blanks. Subsequently, 80 of these samples received surface treatment by sandblasting and 80 samples by grinding.
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