Objective: This study aimed at evaluation of the hearing outcome of using glass ionomer bone cement GIC to manage different patterns of ossicular discontinuity.
Study design: prospective clinical study. Subjects and methods: The study included 53 patients with conductive hearing loss caused by ossicular pathology rather than fixed stapes. Thirty three cases were primary surgery and 20 cases were planned 2nd stage. According to the ossicular situation during surgery the patients were classified into 6 groups. In the 1st group the 3 ossicles were articulated and mobile but the handle of malleus was amputated. GIC was used to elongate the handle by cementing a bone chip to it. In the 2nd group, the Long process of incus LPI was necrosed by the hook of the Shea piston, here,GIC was used to elongate the LPI and reconnect it with the piston. In the 3 rd group, only the handle of malleus was present and a bone chip or the preserved incus was cemented with the GIC both medially to the foot-plate and laterally to the handle of malleus. In the 4th group The incudo-stapedial joint ISJ was necrosed and the GIC was used to establish the connection of the LPI to the stapes. In the 5 th group, malleus to stapes assembly was established with a bone chip or incus remnant fixed in place with the GIC. In the last group GIC was used to elongate the stapes to become as lateral as the tympanic membrane. Hearing results at about one year were analyzed.
Results: The Pure tone average PTA improvement was 12.2 dB. Forty eight patients showed a degree of PTA improvement, 4 cases showed no improvement and one case showed a 15 db deterioration. There was an average air -bone gap ABG improvement by 13 dB. The best improvement in the ABG was in the group with ISJ reconstruction and the least was in the group of malleus handle elongation. No complications were reported rather than that case of 15 dB hearing deterioration. The preparation, handling and cementing with the GIC is simple and easily mastered.
Conclusion: GIC is a good tool available to the otologist. It can be used alone to re-establish the continuity of the ossicular chain in minor ossicular chain defects. It can also be used to stabilize other forms of re-bridging surgery.