Ionomer-based bone substitute in otologic surgery

Abstract

During post-set hardening the self-curing bone substitute Ionocem develops a solid bond with the adjacent bony tissue, leaving no empty spaces. The fully matured material can be fixed to bone with freshly mixed cement or it may be used as a blank, e.g. an ossicular implant (Ionos ossicle). After insertion of 945 alloplastic middle ear prostheses over a period of 4.5 years, the take-rate was 94%. In some patients revision surgery became necessary, in 50% of cases because of prosthesis dislocation. A granular version of the cement (Ionogran) was implanted in 46 ears for obliteration of mastoid cavities and showed complete mucosal overgrowth within a maximal period of 3 months. Posterior canal wall reconstruction with the self-curing bone substitute was done in 74 patients, with revisions required in 12 cases because of persistent epithelial deficits in the external ear canal or epitympanic retraction. Overall results showed that the ionomer-based cement was a useful substitute for bone in reconstructive otologic surgery.

Titanium and Glass-Ionomer Cement as Ossicular Replacement Materials: Biocompatibility Results after Implantation in the Rabbit

“…Because of this, in vitro experiments cannot be substituted for carefully controlled long-range animal studies [5]. Although there are only a few reports of titanium for bone replacement in the middle ear [10,25], and a greater number of clinical applications of glass-ionomer cement [7][8][9], the clinical results correlate with the results of our animal study.…”

“…Glass-ionomer cement was first developed as a material in the field of dentistry, exhibiting good functional and biological results [6]. The use of glass-ionomer cement for middle ear prostheses is now widespread [7][8][9], but titanium is just now beginning to be used in human middle ear surgery [10].…”

A long-term study on the setting reaction of glass ionomer cements by 27Al MAS-NMR spectroscopy

“…Over the last ten years they have also been developed for medical applications [2] and are now commercially available as a bone cement and as a pre-set cancellous bone substitute. They are the adhesive of choice for cementing cochlear implants [3].…”

Evaluation on Shear Bond Strength of Different Glass Ionomer and Hydroxy Apatite Cements Used in Ossiculoplasty

“…In patients requiring revision of surgery, Geyer and Helms reported that half of the failures resulted from the displacement of prosthesis (8). However, there is no information about the character of bonding failures of bone cement ossiculoplasty.…”