Should the ossicle be denuded prior to the application of glass ionomer cement? An experimental study on rabbit

Abstract

The objective of this study was to assess whether denudation of the auditory ossicle prior to the application of glass ionomer cement (GIC) durably strengthens the adhesion between bone and GIC. The tympanic bullas of 34 rabbits were opened bilaterally. The mucosa was removed from the lateral surface of the right-side incudi with a diamond burr, while the left-side incudi were left intact. GIC was then applied bilaterally to the lateral surface of the incudi of 30 of these rabbits which were subsequently killed 1, 3, 7, 14, 21, 30, 60, 90, 180 or 365 days postoperatively. The 4 sham-operated animals were killed on day 1, 7, 30 or 365. The incudi were removed and processed for histological evaluation. On exploration, the cement was visible on the incus within the tympanic bulla in all 30 GIC-treated animals. During surgical removal, the GIC was separated from the incus in 3 ears. Histological examination further revealed separation in 5 ears after processing. All 8 separations occurred in the right (not denuded) ears, and at least 60 days postoperatively. The difference between the two sides in the number of separations was significant (p < 0.05). The initial inflammatory reaction elicited by the surgical trauma to the right-side ossicles had substantially decreased by day 7. No foreign body reaction was observed and the GIC became overgrown with mucosa by day 60. In conclusion, the GIC proved biocompatible, and preliminary denudation of the ossicle resulted in stronger and more durable bone-GIC adhesion.

Glass ionomer application for vocal fold augmentation: Histopathological analysis on rabbit vocal fold

“…Glass ionomer cement has been used in cranioplasty for tegmen and external ear canal reconstructions, mastoid obliteration, and ossicular reconstruction . Biostability, biocompatibility, and cost‐effectiveness have made GIC a preference for use in otology . However, the low initial pH of GIC or ionic secretion from the glass particles may lead to toxicity …”

“…GIC hardens after an acid–base neutralization process between an aqueous solution of a polyacrylic acid and calcium fluoroaluminosilicate glass powder …”

“…Glass ionomer cement has been considered biocompatible, because no foreign body reaction has been seen in animal studies . The biocompatibility of GIC has been reported as minimal exothermic on setting, with rapid neutralization following mixing and a slow release of ions that are generally biologically beneficial, or at least benign …”

Application of ionomer cement onto the stapedial footplate: Impact on the perilymphatic aluminum level

“…The hardening reaction of the cement is based on the gelation of the polymeric acid through the cross‐linking of the carboxyl groups in the acid with aluminum (A1) and calcium ions released from the cement powder . With a paste‐like consistency, the material is easily workable, binds well to bare bone surfaces, and sets within a few minutes, leaving time for manipulation in the tympanic cavity before it hardens to a bony‐like structure that exhibits excellent mechanical properties and biocompatibily …”

“…3 With a paste-like consistency, the material is easily workable, binds well to bare bone surfaces, and sets within a few minutes, leaving time for manipulation in the tympanic cavity before it hardens to a bony-like structure that exhibits excellent mechanical properties and biocompatibily. 4 The closure of large skull base defects with significant amounts of GIC that came into contact with the cerebrospinal fluid (CSF) was earlier reported to result in Al-induced encephalopathy. [5][6][7] This unfortunate event was followed by restrictions on the usage of GIC in otoneurosurgery.…”