Quantification of titanium from TiO2 particles in biological tissue

Quantification of titanium and zirconium elements in oral mucosa around healthy dental implants: a case-control pilot study

OBJECTIVES

Metallic particles are detected in different sites of the oral cavity, mainly in patients with peri-implantitis lesions. The aim of this pilot study was to analyze the levels of titanium and zirconium elements in the oral mucosa around healthy implants and to investigate the impact of titanium exogenous contamination on the measurements.

MATERIALS AND METHODS

Forty-one participants were included in this three-phase study. Two groups of subjects were defined according to presence of titanium or zirconia implants (n: 20) or without any implants nor metallic restorations (n:21). Thirteen patients (n: 5 with zirconia implant; n: 3 with titanium implants; n: 5 control group) took part to the first part designed to optimize and validate the method of detecting titanium (Ti) and zirconium (Zr) elements in the oral mucosa and gingival tissues by the Inductively Coupled Plasma Mass Spectrometry (ICPMS). The second phase compared the levels of Ti and Zr concentrations in patients with implants (n: 12) and without implants (n: 6) who were controlled for their intake of titanium dioxide (TiO2). The last step included ten control subjects without any metallic devices to measure the concentration of Ti and Zr before and after having candies containing TiO2.

RESULTS

In the first phase, concentrations of Ti and Zr were below the limit of detection (LOD) in most cases, 0.18 μg/L and 0.07 μg/L respectively. In the titanium group, two out of three subjects displayed concentrations above the LOD, 0.21 μg/L and 0.66 μg/L. Zr element was only found in patients with zirconia implants. After controlling the intake of TiO2, all concentrations of Ti and Zr were below the limit of quantification (LOQ). Moreover, in patients with no implants, the Ti concentration in gingiva cells was superior for 75% of the samples after having a TiO2 diet.

CONCLUSIONS

Zirconium was only found in patients with zirconia implants, whereas titanium was detected in all groups even in subjects with no titanium implants. Zirconium and titanium elements were not detected in patients who were controlled for their intake of food and their use of toothpaste irrespective of the presence of implants or not. For 70% of the patients, the titanium detection was directly influenced by the intake of TiO2 contained candies.

CLINICAL RELEVANCE

When analyzing titanium particles, it is necessary to pay attention to the risk of contamination bias brought by external products. When this parameter was controlled, no titanium particles were detected around clinically healthy implants.

Tracking soluble and nanoparticulated titanium released in vivo from metal dental implant debris using (single-particle)-ICP-MS

BACKGROUND

This work studies the presence of the Ti, Al and V metal ions and Ti nanoparticles released from the debris produced by the implantoplasty, a surgical procedure used in the clinic, in rat organs.

METHODS

The sample preparation for total Ti determination was carefully optimized using microsampling inserts to minimize the dilution during the acid attack of the lyophilized tissues by a microwave-assisted acid digestion method. An enzymatic digestion method was optimized and applied to the different tissue samples in order to extract the titanium nanoparticles for the single-particle ICP-MS analysis.

RESULTS

A statistically significant increase was found for Ti concentrations from control to experimental groups for several of the studied tissues, being and particularly significant in the case of brain and spleen. Al and V concentrations were detected in all tissues but they were not different when comparing control and experimental animals, except for V in brain. The possible presence of Ti-containing nanoparticles mobilized from the implantoplasty debris was tested using enzymatic digestions and SP-ICP-MS. The presence of Ti-containing nanoparticles was observed in all the analyzed tissues, however, differences on the Ti mass per particle were found between the blanks and the digested tissue and between control and experimental animals in some organs.

CONCLUSION

The developed methodologies, both for ionic and nanoparticulated metal contents in rat organs, have shown the possible increase in the levels of Ti both as ions and nanoparticles in rats subjected to implantoplasty.

Titanium Dioxide in Food Products: Quantitative Analysis Using ICP-MS and Raman Spectroscopy

Titanium dioxide (TiO₂) is commonly used as a color additive in food products. In this study, a total of 11 food products, such as a coffee cream, yogurt snack, hard candy, and chewy candy, that are widely consumed by adults or children were investigated. For characterization of particle size, size distribution, crystallinity, and concentration of TiO₂, particles were first extracted using an acid digestion method from food, and various analytical techniques were applied. All products investigated in this study contained nanosized TiO₂ particles (21.3-53.7%) in the anatase phase. The particle size of TiO₂ was in the range of 26.9-463.2 nm. The concentration of TiO₂ in the products ranged from 0.015% (150 ppm) to 0.462% (4620 ppm). These values obtained using inductively coupled plasma-mass spectrometry (ICP-MS) were considered as the reference and were compared with Raman results to evaluate the feasibility of using the Raman method to quantitate TiO₂ in food products. The Raman method developed in this study proved to effectively analyze anatase TiO₂ in food products at levels of several hundred parts per million or greater. Limitations of using the Raman method as a quick screening tool for determination of TiO₂ are also discussed.

Review of analytical studies on TiO2 nanoparticles and particle aggregation, coagulation, flocculation, sedimentation, stabilization

Titanium dioxide (TiO₂) nanoparticles (NPs) have been widely used in industrial and consumer products. Comprehensive and accurate detection, characterization, and quantification of TiO₂ NPs are important for understanding the specific property, behavior, fate, and potential risk of TiO₂ NPs in natural and engineered environments. This review provides a summary of recent analytical studies of TiO₂ NPs and their aggregation, coagulation, flocculation, sedimentation, stabilization under a wide range of conditions and processes. Much attention is paid on sample preparation prior to an analytical procedure, analysis of particle size, morphology, structure, state, chemical composition, surface properties, etc., via measurements of light scattering and zeta potential, microscopy, spectroscopy, and related techniques. Recently, some advanced techniques have also been explored to characterize TiO₂ NPs and their behaviors in the environment. Many issues must be considered including distinction between engineered TiO₂ NPs and their naturally occurring counterparts, lack of reference materials, interlaboratory comparison, when analyzing low concentrations of TiO₂ NPs and their behaviors in complex matrices. No "ideal" technique has emerged as each technique has its own merits, biases, and limitations. Multi-method approach is highlighted to provide in-depth information. Improvements of analytical method for determination of TiO₂ NPs have been recommended to be together with exposure modelers and ecotoxicologists for maximum individual and mutual benefit. Future work should focus on developing analytical technology with the advantages of being reliable, sensitive, selective, reproducible, and capable of in situ detection in complicated sample system.

Titanium release in peri-implantitis

OBJECTIVES

The aim of this study was to investigate the titanium (Ti) content of biopsies from patients with severe peri-implantitis or controls without Ti exposure.

BACKGROUND

Peri-implantitis is considered to be an infectious disease, but recent studies have shown that Ti can aggravate inflammation in combination with bacterial products. The Ti content of peri-implantitis and periodontitis (controls) tissue is unknown.

METHODS

Thirteen patients referred for peri-implantitis and eleven for periodontitis treatment were included in the study. Disease severity was obtained from dental records. Biopsies were taken from both groups and chemically analysed with inductively coupled plasma mass spectrometry for Ti content. Additionally, two patients with peri-implantitis and two with periodontitis were recruited and their biopsies were analysed microscopically with light microscopy, transmission electron microscopy and scanning electron microscopy with element analysis to investigate the presence of particulate Ti.

RESULTS

All patients lost one or more implants despite undergoing peri-implant or treatment. Peri-implantitis tissue contained significantly higher concentrations of Ti than control samples with a mean ± SD of 98.7 ± 85.6 and 1.2 ± 0.9 μg/g, respectively. Particulate metal was identified in peri-implantitis and control biopsies, but element analyses could confirm only the presence of Ti in peri-implantitis tissue.

CONCLUSION

We showed that high contents of particulate and submicron Ti were present in peri-implantitis tissue. These high Ti contents in peri-implant mucosa can potentially aggravate inflammation, which might reduce the prognosis of treatment interventions.

Validation of a Sulfuric Acid Digestion Method for Inductively Coupled Plasma Mass Spectrometry Quantification of TiO2 Nanoparticles

A consistent analytical method incorporating sulfuric acid (H₂SO₄) digestion and ICP-MS quantification has been developed for TiO₂ quantification in biotic and abiotic environmentally relevant matrices. Sample digestion in H₂SO₄ at 110°C provided consistent results without using hydrofluoric acid or microwave digestion. Analysis of seven replicate samples for four matrices on each of 3 days produced Ti recoveries of 97% ± 2.5%, 91 % ± 4.0%, 94% ± 1.8%, and 73 % ± 2.6% (mean ± standard deviation) from water, fish tissue, periphyton, and sediment, respectively. The method demonstrated consistent performance in analysis of water collected over a 1 month.

Release of titanium after insertion of dental implants with different surface characteristics - an ex vivo animal study

In the present study, amount of titanium (Ti) released into the surrounding bone during placement of implants with different surface structure was investigated. Quantification of Ti released during insertion from three different implants was performed in this ex vivo study. Jaw bone from pigs was used as model for installation of the implants and Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) was used for analysis of the released Ti. Implant surface were examined with scanning electron microscopy (SEM), before and after the placement into the bone. Ti was abraded to the surrounding bone upon insertion of a dental implant and the surface roughness of the implant increased the amount of Ti found. Diameter and total area of the implant were of less importance for the Ti released to the bone. No visible damages to the implant surfaces could be identified in SEM after placement.