Medialisation laryngoplasty with bone wax in a sheep model

Objective To evaluate the safety and biocompatibility of bone wax as an implant material for medialisation laryngoplasty in a large animal model. Methods Three Dorper-cross ewes underwent type I thyroplasty of the right vocal fold with bone wax. The animals were monitored for four weeks for general wellbeing. The animals were euthanised and the larynges harvested. Histological evaluation was performed to assess for adverse tissue reaction and biocompatibility. Results The mean (± standard deviation) amount of bone wax implanted was 0.49 g (± 0.12 g). No adverse events were reported. Ex vivo vibration was present on high-speed imaging for all medialised vocal folds. Histology demonstrated implanted paraffin embedded within the thyroarytenoid muscle with no evidence of resorption, a minimal inflammatory infiltrate, and a thin fibrotic capsule. Conclusion The results of this investigation suggest that bone wax may be a safe and efficacious implant material for medialisation laryngoplasty. Further studies are necessary to assess its long-term safety and efficacy.