Bone response to physical-vapour-deposited titanium dioxide coatings on titanium implants

Advanced Strategies for Enhancing the Biocompatibility and Antibacterial Properties of Implantable Structures

This review explores the latest advancements in enhancing the biocompatibility and antibacterial properties of implantable structures, with a focus on titanium (Ti) and its alloys. Titanium implants, widely used in dental and orthopedic applications, demonstrate excellent mechanical strength and biocompatibility, yet face challenges such as peri-implantitis, a bacterial infection that can lead to implant failure. To address these issues, both passive and active surface modification strategies have been developed. Passive modifications, such as altering surface texture and chemistry, aim to prevent bacterial adhesion, while active approaches incorporate antimicrobial agents for sustained infection control. Nanotechnology has emerged as a transformative tool, enabling the creation of nanoscale materials and coatings like TiO2 and ZnO that promote osseointegration and inhibit biofilm formation. Techniques such as plasma spraying, ion implantation, and plasma electrolytic oxidation (PEO) show promising results in improving implant integration and durability. Despite significant progress, further research is needed to refine these technologies, optimize surface properties, and address the clinical challenges associated with implant longevity and safety. This review highlights the intersection of surface engineering, nanotechnology, and biomedical innovation, paving the way for the next generation of implantable devices.

Anti-TLR4 biological response to titanium nitride-coated dental implants: anti-inflammatory response and extracellular matrix synthesis

Osteointegration is a key process during dental implant placement and is related to titanium surface topography. Implant coating and surface modification methods ameliorate the bone production and the osteogenic process. The current work aimed at evaluating the biological outcomes of two different surfaces of dental implants, machined and titanium nitride (TiN) coated, at an inflammation level using an in vitro model of human periodontal ligament stem cells. The TLR4/MyD88/NF-κB p65/NLRP3 pathway induced by the Porphyromonas gingivalis lipopolysaccharide was studied by means of gene- and protein-level expression. Moreover, the expression of vimentin, vinculin, and fibronectin was evaluated to investigate their effects on the cell adhesion and extracellular matrix deposition. The results of the present study suggest that TiN-coated titanium disks may modulate inflammation by the suppression of the TLR4/MyD88/NF-κB p65/NLRP3 pathway and accelerate extracellular matrix apposition.

A Novel Technique to Increase the Thickness of TiO₂ of Dental Implants by Nd: DPSS Q-sw Laser Treatment

High bone-implant contact is a crucial factor in the achievement of osseointegration and long time clinical success of dental implants. Micro, nano, microtopography, and oxide layer of dental implants influence tissue response. The lasers were used for achieving an implant surface with homogeneous micro texturing and uncontaminated surface. The present study aimed to characterize the implant surfaces treated by Nd: DPSS Q-sw Laser treatment compared to machined implants. A total of 10 machined implants and 10 lasered surface implants were evaluated in this study. The implant surfaces were evaluated by X-ray Photoelectron Spectroscopy (XPS), Auger Electron Spectroscopy (AES), and metallography to characterize and measure the thickness of the oxide layer on the implant titanium surface. The machined surfaces showed a non-homogeneous oxide layer ranging between 20 and 30 nm. The lasered implant surfaces showed a homogeneous oxide layer ranging between 400 nm and 460 nm in the area of the laser holes, while outside the layer, thickness ranged between 200 nm and 400 nm without microcracks or evidence of damage. Another exciting result after this laser treatment is a topographically controlled, repeatable, homogeneous, and clean surface. This technique can obtain the implant surface without leaving residues of foreign substances on it. The study results indicate that the use of Nd: DPSS Q-sw laser produces a predictable and reproducible treatment able to improve the titanium oxide layer on the dental implant surface.

Influence of the Thermal Treatment to Address a Better Osseointegration of Ti6Al4V Dental Implants: Histological and Histomorphometrical Study in a Rabbit Model

Background

Pure titanium continues to be the first choice for dental implants and represents the gold standard for their biocompatibility and physical and mechanical characteristics, while the titanium alloy (Ti6Al4V) has good mechanical properties. The surface structure of the titanium oxide layer formation on the surface influences and improves the bone response around dental implants.

Purpose

The purpose of this study is to evaluate the influence of a thermal treatment of Ti6Al4V implant surfaces and the bone healing response in a rabbit model.

Methods

Altogether sixteen implants with same design were inserted into the distal femoral metaphysis. A screw (13 mm long, 4 mm in diameter) was inserted in an implant bed. Each rabbit received two implants, one in the left femur and one in the right femur. The samples were histologically and histomorphometrically evaluated at 8 weeks.

Results

A statistically significant difference (p = 0.000034) was present histologically in the percentages of bone-implant contact (BIC) between the test group (BIC = 69.25±4.49%.) and control group (BIC = 56.25 ± 4.8%) by one-way analysis of variance (ANOVA). Significance was set at p ≤ 0.05.

Conclusions

The outcome of the present study indicates a novel approach to improving bone healing around titanium implants.

Reduced bacterial growth and increased osteoblast proliferation on titanium with a nanophase TiO2 surface treatment

Background

The attachment and initial growth of bacteria on an implant surface dictates the progression of infection. Treatment often requires aggressive antibiotic use, which does not always work. To overcome the difficulties faced in systemic and local antibiotic delivery, scientists have forayed into using alternative techniques, which includes implant surface modifications that prevent initial bacterial adhesion, foreign body formation, and may offer a controlled inflammatory response.

Objective

The current study focused on using electrophoretic deposition to treat titanium with a nanophase titanium dioxide surface texture to reduce bacterial adhesion and growth. Two distinct nanotopographies were analyzed, Ti-160, an antimicrobial surface designed to greatly reduce bacterial colonization, and Ti-120, an antimicrobial surface with a topography that upregulates osteoblast activity while reducing bacterial colonization; the number following Ti in the nomenclature represents the atomic force microscopy root-mean-square roughness value in nanometers.

Results

There was a 95.6% reduction in Staphylococcus aureus (gram-positive bacteria) for the Ti-160-treated surfaces compared to the untreated titanium alloy controls. There was a 90.2% reduction in Pseudomonas aeruginosa (gram-negative bacteria) on Ti-160-treated surfaces compared to controls. For ampicillin-resistant Escherichia coli, there was an 81.1% reduction on the Ti-160-treated surfaces compared to controls. Similarly for surfaces treated with Ti-120, there was an 86.8% reduction in S. aureus, an 82.1% reduction in P. aeruginosa, and a 48.6% reduction in ampicillin-resistant E. coli. The Ti-120 also displayed a 120.7% increase at day 3 and a 168.7% increase at day 5 of osteoblast proliferation over standard titanium alloy control surfaces.

Conclusion

Compared to untreated surfaces, Ti-160-treated titanium surfaces demonstrated a statistically significant 1 log reduction in S. aureus and P. aeruginosa, whereas Ti-120 provided an additional increase in osteoblast proliferation for up to 5 days, criteria, which should be further studied for a wide range of orthopedic applications.