Absorbable biomaterials used within paranasal sinuses: an animal study.

BACKGROUND: The purpose of this study was to investigate the quality of mucosal regeneration in the presence of two different resorbable dressings derived from hyaluronic acid (HA): HA-carboxymethyl cellulose (HACMC) and esterified HA (HYAFF). A prospective randomized animal study was performed.

METHODS: Twelve New Zealand white rabbits underwent bilateral maxillary sinusomy via a canine fossa approach. Each sinus was stripped circumferentially, except for the mucosa along the medial wall in the region of the natural ostium. Each of the 24 sinuses was then packed with either HACMC (n = 8) or HYAFF (n = 8) or left as an unpacked control (n = 8). After 14 days, each animal was killed and the sinus contents were evaluated histologically by a blinded pathologist.

RESULTS: Criteria for optimal mucosal regeneration included a continuous layer of ciliated columnar epithelium with normal-appearing submucous glands and lack of both inflammatory infiltrate and fibrosis. Optimal regeneration was observed in 5/8 (62.5%) of the HACMC specimens, 1/8 (12.5%) of the HYAFF specimens, and 6/8 (75%) of the controls. The trend toward optimal regeneration using either HACMC or control was statistically significant when compared with HYAFF (p = 0.03). HYAFF specimens also were more likely to exhibit atrophic subepithelial glands in the regenerated mucosa. Polarizable foreign material was observed in 1/8 (12.5%) of the HACMC specimens and 2/8 (25%) of the HYAFF specimens.

CONCLUSION: The quality of epithelial regeneration is potentially affected by the form of HA present in the healing milieu. In this series, the most optimal healing characteristics were seen in unpacked controls. Between the preparations of HA studied, HACMC exhibited more favorable healing patterns, which were nearly similar to controls.