Ossification of the frontal sinus in juvenile minipigs following water jet application.

Background: Obliteration of the frontal sinus is a generally accepted management for patients with severe craniofacial trauma in whom the sinus cannot be repaired or adequately drained. Effective obliteration requires complete removal of mucosa, sufficient filling of the sinus cavity as well as effective occlusion of the nasofrontal duct. The use of various filling materials for sinus obliteration has been described and include autologous fat, bone, muscle and lyophilized cartilage.

Material And Methods: In order to appreciate the advantages of the water-jet scalpel an animal study in 10 juvenile (4 months old) and 10 adult (18 months) minipigs was performed. In 5 juvenile and 5 adult animals the frontal sinus mucosa was removed using the water jet, while in the others bone curettes were used. No occlusion of the frontonasal duct was carried out and no filling material was implanted. All animals were followed-up for 40 days. After sacrifice, radiological, histological and computerized histomorphometrical examinations were carried out.

Results: Removal of the mucosa from the sinus was simplified when using the water jet. Previous studies have shown that the selected tissue structures were less traumatized when compared with conventional surgical techniques. In young animals (only) and exclusively following the use of a water-jet scalpel osseous occlusion of the frontal sinus was found at follow-up. Histomorphometric findings revealed a significant increase of bone formation in the frontal sinus area of these animals.

Conclusion: Based on these experimental results in a small series of juvenile minipigs the water-jet technique is a faster and less traumatic technique (less blood loss) for osteoplastic surgery of the frontal sinus. Further long-term studies are needed to evaluate the possibilities for applying this technique in post-traumatic craniofacial surgery in man.