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The nail is the largest skin appendage. In addition to its important physiological and sensory functions, it is also of great esthetic importance. Complaints of brittle or soft nails are frequent, particularly among women. Innumerable preparations claiming to improve the nail quality are being sold; however, most have no proven beneficial effect. Also, surgery cannot enhance nail quality but improve shape and size abnormalities.
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Eckart Haneke (2006) studied this question.
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