A technique for evaluating bone ingrowth into 3D printed, porous Ti6Al4V implants accurately using X-ray micro-computed tomography and histomorphometry.

This paper investigates the application of X-ray micro-computed tomography (micro-CT) to accurately evaluate bone formation within 3D printed, porous Ti6Al4V implants manufactured using Electron Beam Melting (EBM), retrieved after six months of healing in sheep femur and tibia. All samples were scanned twice (i.e.

Electron Beam Melting Manufacturing Technology for Individually Manufactured Jaw Prosthesis: A Case Report.

In the field of maxillofacial reconstruction, additive manufacturing technologies, specifically electron beam melting (EBM), offer clinicians the potential for patient-customized design of jaw prostheses, which match both load-bearing and esthetic demands. The technique allows an innovative, functional design, combining integrated porous regions for bone ingrowth and secondary biological fixation with solid load-bearing regions ensuring the biomechanical performance. A patient-specific mandibular prosthesis manufactured using EBM was successfully used to reconstruct a patient's mandibular defect after en bloc resection.

Bioactive Spheres: The Way of Treating Dentin Hypersensitivity.

Sealing exposed dental tubules is the most effective and long-term way to relieve the pain induced by dental sensitivity. A bioactive hollow sphere (strontium substituted calcium phosphate) was synthesized and added in toothpaste to study its effect on dental hypersensitivity via tooth tubules occlusion and mineralization. The size of spheres is perfect for penetrating into dental tubules, reaching to 20 μm into the tubules.

Long-term osseointegration of 3D printed CoCr constructs with an interconnected open-pore architecture prepared by electron beam melting.

Unlabelled: In orthopaedic surgery, cobalt chromium (CoCr) based alloys are used extensively for their high strength and wear properties, but with concerns over stress shielding and bone resorption due to the high stiffness of CoCr. The structural stiffness, principally related to the bulk and the elastic modulus of the material, may be lowered by appropriate design modifications, to reduce the stiffness mismatch between metal/alloy implants and the adjacent bone. Here, 3D printed CoCr and Ti6Al4V implants of similar macro-geometry and interconnected open-pore architecture prepared by electron beam melting (EBM) were evaluated following 26week implantation in adult sheep femora.

A novel soft tissue model for biomaterial-associated infection and inflammation - bacteriological, morphological and molecular observations.

Infection constitutes a major risk for implant failure, but the reasons why biomaterial sites are more vulnerable than normal tissue are not fully elucidated. In this study, a soft tissue infection model was developed, allowing the analysis of cellular and molecular responses in each of the sub-compartments of the implant-tissue interface (on the implant surface, in the surrounding exudate and in the tissue). Smooth and nanostructured titanium disks with or without noble metal chemistry (silver, gold, palladium), and sham sites, were inoculated with Staphylococcus epidermidis and analysed with respect to number of viable bacteria, number, viability and gene expression of host cells, and using different morphological techniques after 4 h, 24 h and 72 h.

Enhancement of CRF-PEEK osseointegration by plasma-sprayed hydroxyapatite: A rabbit model.

Carbon-fibre-reinforced polyether ether ketone (CFR-PEEK) exhibits excellent biomechanical properties as it has an elastic modulus similar to bone. However, CFR-PEEK displays inferior biocompatibility compared with titanium alloy and coating techniques are therefore of interest in order to improve integration. In this paper, the early biological response to CFR-PEEK implants, with and without hydroxyapatite coating, was investigated.

Osseointegration of titanium with an antimicrobial nanostructured noble metal coating.

Unlabelled: Nanometer scale surface features on implants and prostheses can potentially be used to enhance osseointegration and may also add further functionalities, such as infection resistance, to the implant. In this study, a nanostructured noble metal coating consisting of palladium, gold and silver, never previously used in bone applications, was applied to machined titanium screws to evaluate osseointegration after 6 and 12 weeks in rabbit tibiae and femurs. Infection resistance was confirmed by in vitro adhesion test.

Stability after maxillary segmentation for correction of anterior open bite: a cohort study of 33 cases.

The aim of this cohort study was to evaluate the stability after multi-segmentation of the maxilla for correction of anterior open bite deformities. A total of 33 patients who underwent segmented maxillary osteotomy between 1994 and 2006 were included in the study. Rigid fixation with plates and postsurgical intermaxillary fixation for 6 weeks was applied to each patient.

Acute inflammatory response to laser-induced micro- and nano-sized titanium surface features.

Background: The inflammatory process induced by implant surfaces is an important component of the tissue response, where limited knowledge is available regarding the role of surface topography. With laser ablation, a combined micro- and nanoscale surface modification could be created, which have been shown to enhance bone growth and biomechanical stability in vivo.

Purpose: The aim of this article was to evaluate the early in vivo inflammatory response to laser-modified titanium disks, with machined titanium disks and sham operation sites serving as controls.

Gene expression of inflammation and bone healing in peri-implant crevicular fluid after placement and loading of dental implants. A kinetic clinical pilot study using quantitative real-time PCR.

Purpose: Early detection of healing complications after placement of dental implants is a pressing but elusive goal. This paper proposes a non-invasive diagnostic tool for monitoring healing- and peri-implant disease specific genes, complementary to clinical evaluations.

Material And Methods: Eighteen partially edentulous patients were recruited to this pilot study.

The correlation between gene expression of proinflammatory markers and bone formation during osseointegration with titanium implants.

An in vivo interfacial gene expression model combined with biomechanical analysis was used in order to determine the relationship between the molecular events taking place during osseointegration and the biomechanical stability of the implant. Anodically oxidized and machined, threaded titanium implants were characterized topographically, chemically and ultrastructurally. The implants were inserted in rat tibiae and the implant bone torsion stability was evaluated.

Integrin and chemokine receptor gene expression in implant-adherent cells during early osseointegration.

The mechanisms of early cellular recruitment and interaction to titanium implants are not well understood. The aim of this study was to investigate the expression of pro-inflammatory cytokines, chemokines and adhesion markers during the first 24 h of implantation. Anodically oxidized and machined titanium implants were inserted in rat tibia.

In vivo evaluation of noble metal coatings.

A nanotopographic noble metal (Ag, Au, Pd) coating has been applied on commercial urinary catheters and used in more than 80,000 patients, with good clinical results. We have previously evaluated the biocompatibility of different variations of this coating, showing high cellular viability and function in vitro. However, the reasons for good clinical and preclinical behavior are not known.

The influence of bone type on the gene expression in normal bone and at the bone-implant interface: experiments in animal model.

Background: Studies on the biological processes in different bone types and the reaction of different bone types to biomaterials are often hindered because of the difficulties in sampling procedures and lack of sensitive techniques.

Purpose: The purpose was to assess the suitability of quantitative polymerase chain reaction (qPCR) for investigation of the biological differences between cortical and trabecular bone types and their responses to biomaterials.

Materials And Methods: Gene expression of selected markers in rat bone samples from different locations was evaluated.

In vivo gene expression in response to anodically oxidized versus machined titanium implants.

A quantitative polymerase chain reaction technique (qPCR) in combination with scanning electron microscopy was applied for the evaluation of early gene expression response and cellular reactions close to titanium implants. Anodically oxidized and machined titanium miniscrews were inserted in rat tibiae. After 1, 3, and 6 days the implants were unscrewed and the surrounding bone was retrieved using trephines.

Fibrous capsule formation around titanium and copper.

Previous studies suggest that implant material properties influence the quality and quantity of fibrous capsule around the implant. However, the precise relation between material surface chemistry, early inflammatory response, and fibrous subsequent repair outcome is still unknown. Titanium (Ti) and copper (Cu), surfaces with different inflammatory potential, were implanted subcutaneously in rats and retrieved fibrous capsules were analyzed after 28 and 56 days.

Monocyte viability on titanium and copper coated titanium.

The role of apoptosis/cell death in the inflammatory response at the implanted materials is unexplored. Two surfaces with different cytotoxic potential and in vivo outcomes, titanium (Ti) and copper (Cu) were incubated in vitro with human monocytes and studied using a method to discriminate apoptotic and necrotic cells (Annexin V/PI staining). Further, staurosporine, a potent inducer of apoptosis, was added to the surface adherent monocytes.

In vivo cytokine secretion and NF-kappaB activation around titanium and copper implants.

The early biological response at titanium (Ti), copper (Cu)-coated Ti and sham sites was evaluated in an in vivo rat model. Material surface chemical and topographical properties were characterized using Auger electron spectroscopy, energy dispersive X-ray spectroscopy and interferometry, respectively. The number of leukocytes, cell types and cell viability (release of lactate dehydrogenase) were determined in the implant-interface exudate.