Contributions to the Etiology of the Pneumosinus Dilatans

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Introduction: The forming mechanisms of the pneumosinus dilatans have been investigated for a long time, but are still not totally clear. Besides the genetic and hormonal factors, an entire explanation of the pressure variation of the sinuses is still missing. A contradiction is found in the case of subjects suffering of choanal artesia, who in some cases have quite developed sinuses. The theory claiming that the ostium acts like a high pressure valve, is not...