Yup!!! Been wearing bone conduction hearing aids since I was a little girl, then went to modified BTEs (with the cord, oscillator and headband, the difference being that now the oscillator was behind the ear on one side and the hearing aid itself was behind the other ear, as opposed to a body-worn aid). When as an adult I learned about the BAHA my first thought was, "hey, I could wear TWO of these!" The device was all-in-one: both oscillator and hearing aid in a single, small unit rather than two separate entities of oscillator and hearing aid. No cords needed, no headband needed. Instinctively I knew that I was losing out on a lot by being able to wear just one aid, that the sound field was significantly limited. Humans are born with two ears for a reason. The first time I wore my BAHAs I immediately noticed the difference between hearing with just one side as opposed to hearing on both sides -- a much wider sound field. Doesn't always help with identifying sound location, though, but sometimes it does.
In 2001 I went to Johns Hopkins in Baltimore, MD, and had the appropriate audiogram and CT scans to determine if I were the prime candidate that I seemed to be (bilateral atresia/microtia, successful use of bone conduction devices) and indeed that was the case. I had the implantation surgery in April of that year and in July 2001 was fitted with my first pair of BAHAs. It was truly life-changing. I've been wearing BAHAs ever since and the freedom from headbands and cords and the constant pressure on my skull has been wonderful. I snap a sound processor on to each abutment and away I go.....and it's quick and easy to simply unsnap them to remove them for the night or showering, whatever.
The sound quality is significantly better because the implanted screw is connected to another screw which in turn is connected to the external sound processor via the abutment, and the user is getting much purer, clearer sound right from the bone as opposed to having to go through layers of tissue first.
The original BAHA was developed in Sweden by the Entific Company, which is now Cochlear Americas and worldwide. In addition, there are a few other companies which make variations on the bone-anchored theme, I believe Oticon being one, and research continues on as newer technology allows for development of newer and more effective devices such as the Osia, developed by Cochlear Americas, which has recently been approved by the FDA in the US.
Yes, in general candidates for a BAHA are those with atresia and microtia and those with what used to be called "glue ear," where the patient cannot tolerate anything in the ears such as ear molds due to frequent infections and issues in the ear canal. Those with single-sided deafness due to acoustic neuroma or other causes also benefit from the BAHA as well.
To clarify something: a bone-anchored sound processor, even though there is implantation involved, is very different from a cochlear implant, which also includes part of the device being implanted, and which is used for a different type of hearing loss, usually very severe.
The Bone-anchored hearing aid type of hearing device is definitely not for everyone, but for those of us for whom it is, the technology is remarkable and I am thankful every day for it.