When our eyesight goes fuzzy, we buy glasses. When a tooth aches, we go to the dentist. When a bone breaks, we have a doctor set it and wrap it in a cast.

When our hearing diminishes with age, we crank up the TV loud and pretend everything could not be finer.

Why, as a species, do we tend to resist hearing aids?

"People equate hearing loss with aging and just don't like what hearing aids represent," said audiologist Bill Meissner. "But, actually, this is the best time in history to buy hearing aids. The technology now is the best it has ever been. There's good stuff out there that works."

An estimated 28 million Americans suffer from hearing loss, according to the National Institute of Deafness and Other Communication Disorders.

"(It's) one of the most prevalent chronic health conditions in the United States, affecting people of all ages, in all segments of the population and across all socioeconomic levels," reports the NIDCD on its health information Web site.

The site says that hearing loss affects about 17 in 1,000 children under age 18. The incidence goes up with age, with about 314 in 1,000 people over age 65 having hearing loss. Causes include hereditary factors, disease, trauma, or long-term exposure to damaging noise or medications.

Once thought to be a sure sign of heading over-the-hill — with their wires, clunky sizes and spotty reliability — hearing aids have benefited in the past five years by the same digital technology that makes computers work. Digital hearing aids use a microphone, receiver, battery and computer chip and provide the most flexibility for the audiologist to make adjustments for it, says the NIDCD. Not only are new hearing aids smaller and more discreet, they're more precisely programmed to compensate for a person's exact level of hearing loss.

"Simply put," said Meissner, who has been the audiologist for Peoria (Ill.) Ear, Nose and Throat Group for 23 years, "a hearing aid is a sound amplifier that turns little sounds into bigger sounds. And sort of like an equalizer on a stereo, we can program it to enhance specific frequencies."

No two hearing impairments are the same. Some people have trouble with high-end frequencies, others with low-end sounds. Because they can't hear certain sound frequencies (vowel sounds, for instance, are low-end; consonants high-end), some people can miss hearing specific words in a conversation and are forced to fill in the blanks. For others, it's an issue of volume — leading to loud televisions and radio and constant requests to a speaker to repeat what was not clearly heard.

Audiologists can determine through the use of hearing tests how to adjust a hearing aid. They recommend annual testing after even the slightest hearing loss is suspected.

People with hearing loss may experience some or all of the following problems, according to the NIDCD:

*Difficulty hearing conversations, especially when there is background noise.

*Hissing, roaring or ringing in the ears, called tinnitus.

*Difficulty hearing the television or radio at a normal volume.

*Fatigue and irritation caused by the effort to hear.

*Dizziness or problems with balance.

There are three levels of hearing experts. Doctors, usually otolaryngologists or ear, nose and throat doctors, can diagnose and treat medical reasons for hearing loss. Audiologists require a minimum of a master's degree and must be licensed by the state. Hearing aid dispensers also require state certification, but not the education of an audiologist. They are often more traditional salespeople and are frequently associated with a specific manufacturer of hearing aids.

There are four main types of hearing aids. The smallest are called "completely in the canal" devices and are practically invisible. They are also the most expensive, costing upward of $3,000 each, and are not used generally to assist severe hearing loss.

Next are "in the canal" hearing instruments. These are a little larger devices but still small enough to fit far into the ear canal. Canal hearing aids use a slightly larger battery and are used for mild to moderate hearing loss, according to www.hearingplanet.com.

"In the ear" devices can be seen from the outside and are used for a wide range of hearing loss.

"Behind the ear" hearing instruments are housed in a case that fits behind the ear, require a bigger battery and can provide more amplification than smaller devices, according to www.hearingplanet.com.

All the hearing aids described cost at least $1,500.

Analog hearing aids are still available at a lower cost, but are made with old technology. These instruments, according to Meissner, cost between $700 and $2,000. He warns, however, that the cheapest hearing device is not usually the best hearing device.

"The key is to trust your hearing aid dispenser, not feel like you're being pressured into buying something you're not comfortable with," Meissner said.

Even so, Meissner cautioned against putting off dealing with a hearing loss.

"There are real quality-of-life issues with hearing," he said. "As it gets worse, people become isolated, lonely. Depression can happen, too. There's no good reason to let that happen when there is a lot that can be done to help people hear."