Phage-Loaded Biomimetic Apatite Powder With Antibiofilm Activity to Treat Bone-Associated Infections.

For decades, calcium phosphate (CaP)-based ceramics have been used for coating of bone and joint substitutes after arthroplasty due to their biocompatible properties. Infections following orthopedic replacement occur in 1%-5% of cases, causing serious complications. Biofilm formation either on the biomaterial's surface or on patient's tissues greatly enhances the resistance against antibiotic treatments and can induce a chronic infection, emphasizing the need for novel antimicrobial delivery systems.

Engineering Precise Interconnected Porosity in β-Tricalcium Phosphate (β-TCP) Matrices by Means of Top-Down Digital Light Processing.

This study evaluated the biocompatibility and accuracy of 3D-printed β-tricalcium phosphate (β-TCP) pure ceramic scaffolds. A specific shaping process associating a digital light processing (DLP) 3D printer and a heat treatment was developed to produce pure β-TCP scaffolds leaving no polymer binder residue. The β-TCP was characterised using X-ray diffraction, infrared spectroscopy and the detection of pollutants.

Effect of dimensional variations on the manufacturing process and the 3D shrinkage ratio of stereolithographic dental alumina ceramics.

The purpose of the present study was to evaluate the influence of height and length variations of alumina ceramics manufactured by stereolithography on deformations caused by the manufacturing process and on the 3D shrinkage ratio to control the final dimensions and improve the adaptation of stereolithographic ceramic dental prostheses. Two different U-shaped models were designed with variable heights or lengths. The specimens were manufactured by stereolithography and were scanned using a microtomographic device before and after the heat treatment.

Polydopamine treatment of chitosan nanofibers for the conception of osteoinductive scaffolds for bone reconstruction.

We report the influence of treatment time of electrospun chitosan nanofibers (CHT NFs) in dopamine hydrochloride bath (2 mg.mL in 10 mM Tris buffer, pH 8.5) on the extent of the polydopamine (pDA) coating on NFs surface.

A Localized Phage-Based Antimicrobial System: Effect of Alginate on Phage Desorption from β-TCP Ceramic Bone Substitutes.

Tricalcium phosphate (TCP) is a prosthetic material commonly used as a bone substitute to repair osteoarticular diseases and injuries. In this type of bone reconstruction surgery, antibiotics remain the common preventive and therapeutic treatment for bacterial infection. Nevertheless, the emergence of multi-resistant strains requires complimentary or alternative treatments.

3D printed bioceramic for phage therapy against bone nosocomial infections.

This study provides a new therapeutic response to postoperative joint and bone infections. Alone or in combination with antibiotics, phage therapy has many advantages, including accurate targeting of pathogenic bacteria. In addition, a decrease in harmful side effects can improve the healing process.

Numerical optimization of cell colonization modelling inside scaffold for perfusion bioreactor: A multiscale model.

Part of clinically applicable bone graft substitutes are developed by using mechanical stimulation of flow-perfusion into cell-seeded scaffolds. The role of fluid flow is crucial in driving the nutrient to seeded cells and in stimulating cell colonization. A common numerical approach is to use a multiscale model to link some physical quantities (wall shear stress and inlet flow rate) that act at different scales.

Stereolithography: A new method for processing dental ceramics by additive computer-aided manufacturing.

Objectives: The aim of this study was to compare the physical and mechanical properties of stereolithography (SLA)- manufactured alumina ceramics of different composition to those of subtractive- manufactured ceramics and to produce suitable dental crown frameworks.

Methods: The physical and mechanical properties of a control and six experimental SLA ceramics prepared from slurries with small (S) and large (L) particles (0.46±0.

Optimization and Preclinical Perception of an Artificial Simulator for Endodontic Training: A Preliminary Study.

The aim of this study was to evaluate the performance of ceramic, hybrid ceramic, and commercial plastic bloc root canal simulator (RCS) as preclinical training aids in the learning phase of endodontic treatments. A previously developed hydroxyapatite ceramic RCS was improved by adding epoxy resin to the ceramic matrix to more closely mimic the organic phase of dentin and to simulate the clinical situation as realistically as possible. The sintered hydroxyapatite ceramic RCS was vacuum infiltrated with epoxy resin, and the degree of infiltration was evaluated by methylene blue staining.

Surrogate Outcome Measures of In Vitro Osteoclast Resorption of β Tricalcium Phosphate.

Introduction of porosity to calcium phosphate scaffolds for bone repair has created a new challenge when measuring bioresorption in vitro, rendering traditional outcome measures redundant. The aim of this study is to identify a surrogate endpoint for use with 3D scaffolds. Murine RAW 264.

Numerical and ex vivo studies of a bioprobe developed for laser-induced thermotherapy (LITT) in contact with liver tissue.

This work is based on the production of a bioprobe that is compatible with magnetic resonance imaging (MRI) for laser-induced thermotherapy (LITT) in liver cancer laser therapy. This probe is made of an alumina tube (3-mm diameter) in which an optical fibre is centred and fixed. A shooting window (20mm) is created using a mechanical rectifier.

A novel anatomical ceramic root canal simulator for endodontic training.

Introduction: Endodontic therapy is often complicated and technically demanding. The aim of this study was to develop a reproducible biomimetic root canal model for pre-clinical and postgraduate endodontic training.

Material And Methods: A specific ceramic shaping technique (3D printing and slip casting of a root canal mould) was developed to reproduce canal systems with the desired shape and complexity using a microporous hydroxyapatite (HAp)-based matrix.

Gentamicin-loaded poly(lactic-co-glycolic acid) microparticles for the prevention of maxillofacial and orthopedic implant infections.

Trauma and orthopedic surgery can cause infections as any open surgical procedures. Such complications occur in only1 to 5% of the cases, but the treatment is rather complicated due to bacterial biofilm formation and limited drug access to the site of infection upon systemic administration. An interesting strategy to overcome this type of complications is to prevent bacterial proliferation and biofilm formation via the local and controlled release of antibiotic drugs from the implant itself.

New antibacterial microporous CaP materials loaded with phages for prophylactic treatment in bone surgery.

Hydroxyapatite and beta-tricalcium phosphate (β-TCP) are materials commonly used in bone repair. The most important problem occurring in bone repair surgery is bacterial infection which is usually overcome by treatment with antibiotics. Currently, emergence of multidrug resistant strains has led to development of alternative treatments such as phage therapy.

Photoinactivation of Staphylococcus aureus and Vibrio parahaemolyticus in the model aquatic microcosm: effect of light intensity and dissolved biodegradable organic compound.

The impact of light (1,000 × 100,000 lx) on the inactivation of S. aureus and V. parahaemolyticus has been assessed under different concentrations of dissolved biodegradable organic compound (BOC) at pH 7.

Involvement of cell shape and flagella in the bacterial retention during percolation of contaminated water through soil columns in tropical region.

Microorganisms' retention in soil contributes to the natural purification of groundwater. Bacteria found in groundwater are generally of various shapes. The aim of this study was to assess the importance of cell shape and flagella in bacterial retention during polluted water percolation through two soil columns CA and CB, in the equatorial region in Central Africa.

Molecular interactions between zoledronic acid and bone: An in vitro Raman microspectroscopic study.

The aim of this study was to investigate molecular interactions between a bisphosphonate (BP), zoledronic acid, and bone tissue by the use of Raman microspectroscopy. In this way, samples of hydroxyapatite (HA), as a bone model, and Wistar rat femurs were soaking in zoledronic acid solutions. Sample surfaces were studied by Environmental Scanning Electron Microscopy and Raman spectroscopy.

Antibacterial activity of some lactic acid bacteria isolated from an Algerian dairy product.

In the present study, the antibacterial effect of 20 lactic acid bacteria isolates from a traditional cheese was investigated. 6 isolates showed antibacterial effect against Gram positive bacteria. Streptococcus thermophilus T2 strain showed the wide inhibitory spectrum against the Gram positive bacteria.

Prolonged local antibiotics delivery from hydroxyapatite functionalised with cyclodextrin polymers.

Per-operative infection is a common complication for bone-graft surgery. Combining antiseptic agents with graft materials may offer a solution by increasing local drug concentration at target sites. Aiming to achieve a sustained local antibiotic (ATB) delivery for a widely applied bone substitute material - hydroxyapatite (HA), we attempted incorporating hydroxypropyl-beta-cyclodextrin polymer (polyHPbetaCD) into microporous HA via impregnating either in a CD monomers mixture solution or a pre-synthesized CD polymer solution, followed by thermal fixation processing.

The corrosion and biological behaviour of titanium alloys in the presence of human lymphoid cells and MC3T3-E1 osteoblasts.

Corrosion behaviour of biomedical alloys is generally determined in mineral electrolytes: unbuffered NaCl 0.9% (pH 7.4) or artificial saliva (pH 6.

beta-TCP microporosity decreases the viability and osteoblast differentiation of human bone marrow stromal cells.

Association of osteoprogenitor cells to calcium phosphate ceramics is currently under intense investigation, for its considered ability to induce bone formation and therefore to allow the successful repair of large bone defects. However, if the first experimental and clinical studies provided promising results, lack of new bone formation has been reported in a large number of animal experiments. In this context and since it has been reported that in some conditions, calcium phosphate ceramic microstructure induces ectopic bone formation, we investigated the effects of ceramic microporosity on the behavior of osteoprogenitor cells for the development of hybrid materials.