Tympanosclerosis is a condition caused by hyalinization and subsequent calcification of subepithelial connective tissue of the tympanic membrane and middle ear, sometimes resulting in a detrimental effect to hearing. Signs and symptoms
Myringosclerosis rarely causes any symptoms. Tympanosclerosis, on the other hand, can cause significant hearing loss or chalky, white patches on the middle ear or tympanic membrane. Causes
The aetiology for tympanosclerosis is not extensively understood. There are several probable factors which could result in the condition appearing, including:

Long term otitis media (or glue ear)
Insertion of a tympanostomy tube. If aspiration is performed as part of the insertion, the risk of tympanosclerosis occurring increases. Risk also increases if a larger tube is used, or if the procedure is repeated. Atherosclerosis
There is ongoing research as to whether or not cholesteatoma is associated with tympanosclerosis. If there is an association, it is likely that the two conditions co-exist. Pathophysiology
Increased fibroblast activity results in deposition of collagen. Calcium phosphate plaques then form in the lamina propria of the tympanic membrane. Diagnosis
If lesions are typical, non-extensive and with no detriment to hearing, investigation into the condition is rarely required. Audiometry is used to determine the extent of hearing loss, if any. Tympanometry produces tympanograms which can be different when tympanosclerosis is present. Computerised tomography (CT) can be used to determine if disease is present in the middle ear.
In adults, the stratum corneum is composed of 25 to 30 layers of flattened dead keratinocytes, which are continuously shed and replaced from below. These dead cells are interlaid with lipids secreted by the stratum granulosum just underneath, which help to make this layer of the skin a waterproof barrier. The stratum corneums function is to reduce water loss, repel water, protect deeper layers of the skin from injury, and to repel microbial invasion of the skin. In infants, this layer of the skin is much thinner and more easily disrupted. Urine
Although wetness alone has the effect of macerating the skin, softening the stratum corneum, and greatly increasing susceptibility to friction injury, urine has an additional impact on skin integrity because of its effect on skin pH. While studies show that ammonia alone is only a mild skin irritant, when urea breaks down in the presence of fecal urease it increases pH because ammonia is released, which in turn promotes the activity of fecal enzymes such as protease and lipase. These fecal enzymes increase the skins hydration and permeability to bile salts which also act as skin irritants. There is no detectable difference in rates of diaper rash in conventional disposable diaper wearers and reusable cloth diaper wearers. "Babies wearing superabsorbent disposable diapers with a central gelling material have fewer episodes of diaper dermatitis compared with their counterparts wearing cloth diapers. However, keep in mind that superabsorbent diapers contain dyes that were suspected to cause allergic contact dermatitis (ACD)."