Titanium: The Common Element in Knee Replacements and Jewelry

What do knee replacements and jewelry have in common? I've asked myself this question because my husband had both knees replaced and I make jewelry. There's got to be something we have in common.

Occasionally, I come across bits of information acquired in my jewelry making enterprise that astound me with the new connections they make. Titanium is the tie that binds when it comes to the divergent worlds of knee replacements and jewelry. Titanium is common to both. Let me explain.

Titanium is one of the strongest and lightest metal elements on earth. As such, titanium is widely used where strength and light weight are important.

In some uses, titanium is pure or nearly so, typically at 99.2%. A more common form of titanium is titanium dioxide, TiO₂. This form of titanium is used in sunscreen and in paint. Another form is titanium tetrachloride, TiCl_4, which is used as a skywriting agent, you know, when aerobatic airplanes write words in the sky at air shows. But the most common form of titanium is an alloy, a mixture of titanium with 2 to 20% of other elements, such as aluminum, molybdenum, manganese, iron, vanadium, carbon and others. Elements added in particular percentages change the properties of the particular titanium alloy. This allows the titanium alloy properties to be tailored for its intended end use. The array of products containing titanium alloys is vast, including cars, airplanes, missiles, submarines, golf clubs, frames for eye glasses, dental implants, knee replacements, and jewelry, to name a few.

Yes, there's titanium in knee replacements and other joint replacement devices and prostheses. It was in 1977 that Swedish Professor Per-Ingmar Branemark published his accidental discovery about titanium. In animal studies, the Professor placed a piece of metallic alloy in rabbit femurs. After several months, when he wanted to remove them, they wouldn't come out. The metal material had integrated with living bone in a process now known as osseointegration. It happens only with certain materials. Titanium is the most well known one. Its ability to meld with bone put the strong, lightweight titanium alloys to work in joint replacement devices for hips, knees, shoulders, toes, and dental implants.

Titanium in jewelry? I'm used to working with silver and gold to fashion my jewelry designs. Gold and silver are relatively soft metals. Titanium is hard. It's hard to bend, difficult to solder, and to work with it for jewelry requires lots of special equipment. But it most definitely is used as the gray metal in modern, techno-style jewelry designs. It's also inert in or on the body. This makes titanium the preferred metal for people who are sensitive to other metals in jewelry. Also remember that titanium's most salient characteristics are strength, durability, and light weight. Consequently, titanium in jewelry is used especially in watches and rings. It's the preferred metal for mens' rings, wedding bands, and simple designs where the ring is worn constantly, requires extraordinary durability, and is unadorned with gemstones.

The pricetag for titanium is up there with other precious metals, because the titanium used in jewelry is pure. Unlike other applications, titanium in jewelry contains no other metallic elements as alloys. Less pure titanium increases its strength. Titanium alloys would be impossibly difficult to manipulate into intricate jewelry. Thus, titanium jewelry tends to appear in simple, but decidedly contemporary, designs that I would call 'techno modern.'

Titanium has another surprising use. In some gemstones, titanium produces a star-burst phenomenon. Titanium in the dioxide form is used to impart the star-shaped reflection in star sapphires and rubies.

Star light, star bright

Titanium casts a star tonight.

Hard, gray, strong, light.

Titanium keeps knees walking right.

Sources:

www.news-medical.net

www.wisegeek.com

www.en.wikipedia.org/wiki/dental_implant

www.1weddingband.com