There is a bit of confusion about which of these metals is safer for sensitive ears, or wherever. Niobium is generally available only in a chemically pure form, whereas titanium is available both pure and in a bewildering list of alloys (such as many surgical implant grades).
I list a few of the more popular grades and designations of titanium here. Most of them are hypoallergenic. Most of the jewelry that I sell is pure grade #1 or #2 titanium. Some of my ball posts are an alloy, medical implant certified, and with no detectable trace of dreaded nickel.
The etching and anodizing process strip the few percent of non-titanium elements from the surface, and then create a protective shield of titanium dioxide.
Chemically speaking, titanium is less likely to be absorbed by biological systems than niobium. Neither should cause an immune response or allergic reaction.
But when it comes to piercings, part of the issue is abrasion. Titanium is a hard metal that could have a slightly rough surface on the microscopic scale. The act of putting it in might abrade a tight hole.
Niobium is a softer metal, so the surface will yield more to pressure. This might make it better for extremely sensitive skin. The same softness is why the initially brighter colors of niobium don’t last as long as titanium colors.
Whereas I am distinctly a titanium partisan, my colleague at Wear-Earrings-Again.com prefers niobium, from her personal experience.
When in doubt, try both. If both work, then choose only by price, color and design.
The Mrtitanium Forum 
Agreed.
Although I am not a “purist” by any means, I can’t help but to be convinced that it is the “chemical reaction that happens between two dissimilar metals (alloy) in the presence of moisture” that is actually what the super sensitive have allergic reaction to.
What other reason could possibly be the problem, for example, when an individual can comfortably contact 24k Gold, but not 18k Gold? Or Fine Silver (.999) but not Nickel Free Sterling Silver (.925) ?
Currently, the general consensus is that a person can be allergic to anything. But I don’t believe it. How many people do you know that are allergic to air? Or water? Medical Science has discovered that those who suffer immune disorders, such as eczema/dermatitis, are prone to react to a specific list of items. See http://www.wear-earrings-again.com/research2.html.
So if my theory is correct, then non-alloyed Titanium, and Niobium are NON-allergenic. But while testing this theory for yourself, keep the area dry, and be careful not to add an element from that “prone to reaction” list above, such as anti-biotic creams, or your test results will be inaccurate.
-Maggie
This reaction between dissimilar metals in the presence of moisture is called an electrolytic reaction. This reaction is stopped if a non-soluble and non-conductive layer forms.
In alloys of silver and gold, the secondary metal is copper, which primarily reacts to produce copper oxide, a soluble and conductive salt that can be a skin irritant. Small amounts of Nickel can also react and dissolve, and this is a common irritant. Nickel is also hard to remove from low temperature metals like silver and gold. 24k gold has more nickel in it than do standard titanium alloys.
In alloys of titanium, the moisture cannot reach the metals though the titanium dioxide layer. You need to apply voltage or heat to break down this barrier, and anything much less than red hot or 12 volts (if uncolored) won’t do it. If the titanium is colored, then the necessary voltage can be as high as 110 volts. Humans produce as much as 0.07 volts in our most active cells.
Titanium dioxide is like glass. Only chemicals that can dissolve glass can chemically (biologically) attack titanium. This is why alloys of titanium are the preferred material for structural implants in our bodies, like for hips and teeth.
This is fascinating Dan!
So this dioxide layer on Titanium, is this the layer that I have read re-forms when broken? Or would one have concern if we were to, say, cut through a titanium wire? Or even to expose titanium to 12 volts, for that matter…would the alloys then be exposed for all time?
I know, we can’t beleive everything we read, but I do love to test the theories to find what works for me. I’ve read that other elements also have layers that form on them. I’ve even read that Surgical Steel has a protective chromium oxide layer that forms on it that is bio-impermeable, yet I still react almost instantly when in contact with it.
I have been told that the surface of Titanium is somewhat pitted from the spounge like Titanium material it is formed from when purified, and that these pits provide space for bacteria to grow, or even may cause abrasion to the skin when passed over or through it. But there is a huge difference between an infection, abrassion, and allergy, so I’m still very skepticle.
This professional body piercer http://www.crazychameleon.net/bets-body-jewelry-materals.html#Niobium suggests that the tools we use to forge Titanium & Niobium can leave trace allergen elements on the surfaces that are coming in contact with our bodies and causing reactions. Being one who is ultra sensitive, I suppose this is a concern.
However, I still lean more towards the idea that much depends on the environment that the element is in. Many people, for instance, can easily wear 14k gold on the outside of the skin (where it is dry) but cannot wear it in a piercing (where it is wet when it is still an open wound). This little voice also tells me that the environment inside of bone or tooth, is also much different than that inside of flesh.
Very interesting.
-Maggie
Applying heat or voltage (though an electrolyte) to titanium only increases the dioxide layer. Titanium likes oxygen so much that it does bind instantly to oxygen when exposed to air.
Steel tools probably do leave traces on freshly formed titanium (or silver, gold, etc). But the finishing usually removes such traces. Anodizing certainly would.
Titanium, as a hard metal, is prone to a rougher surface that might harbor any bacteria that can live on glass. Anodized surfaces are generally smoother.
Very Interesting! Thanks for sharing your expertise!!!
Well, I am not concerned with bacteria, or abrasions, as I know how to prevent and heal from these. It is definately the allergic reactions that are such a great concern for me and my customers.
So, this glass like layer that forms on Titanium (whether alloyed or not?), scientifically speaking, can not be etched or broken down by high levels of acid produced by the human body?
My question comes from the fact that I’ve been convinced (as you know) that it is the electrolytic reaction that causes allergic contact dermatitis/eczema for us. I first came to this conclusion when I tried to heal my own piercings with alloyed Titanium, unsuccessfully, however, Niobium or Pure Grades of Titanium were successful.
There is also the factor that something else could have caused the reaction, maybe something in the water or my body soap (I’m stretching here) but if there is a possibility that high levels of acid in the body could etch that “glass like” layer, then I think I’m more prone to deduct that instead.
What do you think about this?
-Maggie
Titanium dioxide is a very tight molecule. The only thing that can eat into the oxide layer on titanium is fluoride ions, as in hydrofluoric acid. In the body Fluorine tightly bonds to calcium and Magnesium (bones and teeth), so it is not generally found in the skin.
I am super sensitive to nickel. As in, I make all my pants to avoid any nickel and change parts in all my bras. I also have very baffling allergies – any form of mushrooms mean I need a double dose of epi, four doses and long ICU stay from pineapple and mango, and the fun of nausea from fermented food/drink. I look like an extremely picky eater for good reasons.
Titanium jewelry, both in “standard” piercings and surface piercings, has always been fine. Tygon and Bioplast will harden up and become brittle within a week. But, for the doctor confusing fun – niobium. Full on reaction – swelling in a well healed piercing, extremely itchy and sore, drains a clear, sticky liquid, not normal crusties, and if topical antihistamines are applied, the piercing behaves for a few hours. It’s blatantly clear it’s an allergic reaction. To both anodized and non anodized. Titanium actually changes colors slightly if not anodized after long term wear – one of my always in, early Neometal post is vaguely copper now. Not noticeable until next to brand new titanium. Anodized to the darker colors (blurple, dark blue, etc) and even 6 years later with constant wear in my tragus, no color change.
I am amazed at how sensitive one can be. The color change while wearing titanium is slightly puzzling, too. THere is some very active chemistry going on there.
All I know is that I have tried every metal with bad reactions, except to niobium. It is the absolute only metal I can wear without a reaction. And having heard that the colors wear off I don’t even trust trying those. So I am stuck with the rather dark grey color of the niobium. But at least I can wear earrings again!