In 1995 - 1996 at the ENT Clinic of the Faculty Hospital in Ostrava a total of 24 one-stage operations of the middle ear were performed where for reconstruction of the chain of ossicles prefabricates of hydroxyapatite were used (Ca10 (PO4)6(OH)2) with a porosity of 1.4% type PORP, TORP according to Wehrs and Grote and a grooved interponate to bridge the incudostapedial defect according to Applebaum. For reconstruction of the posterior wall of the auditory meatus and for filling the trepanation cavities the authors used porous hydroxyapatite with a porosity of 20-30% in the shape of a plate - a cone-shaped sector and prisms. In all instances of reconstruction of the chain of ossicles, posterior wall of the auditory meatus and obliteration of the trepanation defect anatomical incorporation occurred without rejection of the ceramic material. Only in one instance in an infected medium the prosthesis and filling of the trepanation defect were rejected after one month. Perforation of the tympanoplastic graft without rejection of the ceramic prosthesis type PORP occurred once when three months after surgery tympanometrically obstruction of the Eustachian tube was revealed. Compact as well as porous hydroxyapatite ceramics are easily processed, they are compatible in direct contact with the ear drum, contrary to other hitherto used alloplastic bioactive materials.

        Key words: chain of ossicles, hydroxyapatite, compact, porous, bioactive, reconstruction.