Comparison of fast-setting calcium phosphate bone cement and fat autograft in a rabbit model of frontal sinus obliteration

Background: Traditionally, chronic obstruction of the frontal recess is managed by frontal sinus obliteration (FSO). This often requires the harvest of abdominal fat as a filler with all of its associated morbidity. In this study, we investigate the efficacy of calcium phosphate bone cement (Craniofacial Repair System [CRSI) as a material for FSO. Methods: Eighteen New Zealand white rabbits were divided into three groups and carried out to two time periods. Six rabbits underwent FSO with fat autograft (control group) and 12 rabbits underwent FSO with CRS (study groups 1 and 2, respectively). At 52 weeks, six control and six study rabbits were killed. The remaining six rabbits were killed at 78 weeks. All specimens underwent radiological evaluation with spiral computed tomography (CT) followed by gross inspection. Histological evaluation was then performed to assess bony growth and to evaluate the interface of the sinus wall with the obliterative material. Results: Sinuses obliterated with CRS showed complete obliteration radiographically. This was apparent at 52 weeks and remained static at 78 weeks. Histological analysis indicated persistent obliteration of the sinus cavity from 52 to 78 weeks and signs of osteoinduction. There were no complications observed as a result of the operative procedure or the materials used. Conclusion: CRS is an alternative to fat autograft for FSO in this noninfected animal model. Further studies are needed to evaluate its long-term efficacy as well as its behavior in chronically infected sinuses.