Hydroxyapatite in the Infected Middle Ear

In order to test the suitability of hydroxyapatite implants for use in tympanoplasty, a study was performed in which the behaviour of these biomaterials was observed in the infected middle ear of the rat. Infection was induced by means of intratympanical injection of a Staphylococcus aureus suspension. The reactions observed show great resemblance with the events witnessed in the middle ear infected without implant. Another similarity can be demonstrated between the implant inserted in the infected tympanon and the implant remaining in the non infected middle ear cavity. All implants are characterized by a mucosal and bony lining. Macropores, when present, become filled with fibrous tissue, gradually replaced by bone. The bonding between the tissue and the implant appears to be tight.