There are a few possible avenues through which we might eventually be able to 'repair' damage to the inner ear. The first, detailed in Frontiers in Cellular Neuroscience, involves gene therapy. By identifying the genes that stimulate the growth of hair cells in other areas of the body, researchers hope to eventually apply them to the inner ear.
An equally promising line of research, published in the scientific journal eLife, involves examining other species that exhibit hair cell regeneration, such as birds and amphibians. Although this capability was discovered more than 30 years ago, the mechanics of it remained a mystery. Replicating it in mammals was more or less impossible.
Recent experiments with mice and rats, however, have succeeded in applying growth-promoting molecules, known as trophic factors, to the inner ear.
Although both of the methods detailed above are a long way from being approved for human usage, it's still confirmed evidence that damage to the inner ear need not be permanent. And it should serve to inspire a glimmer of hope in anyone suffering from hearing loss. Hope that perhaps one day in the future, the world around them will no longer be silent.