Orodispersible hyaluronic acid film delivery for oral wound healing in rats

BACKGROUND/PURPOSE: Oral wound healing undergoes a dynamic process of oral environment. This study aimed to investigate the effects of hyaluronic acid (HA) film on oral wound healing in a rat model. MATERIALS AND METHODS: A total of 60 rats with tongue wounds (5 mm in diameter) were randomly divided into control (n = 20), HA gel (n = 20), and HA film groups (n = 20). The animals were sacrificed on either 3 or 7 days after the experiment. Clinical, histological, and quantitative reverse transcriptase-polymerase chain reaction analysis were performed to evaluate the healing rate, inflammation, re-epithelialization, and gene expression of wound healing biomarkers. RESULTS: The healing rates of HA gel (84.4 ± 9.2%) and HA film (74.0 ± 15.0%) were significantly higher than that of the control (51.7 ± 16.9%) on day 7 (P < 0.001 and P = 0.002, respectively). Histological analysis revealed no significant differences between the groups on day 3. On day 7, only the HA film showed significant improvement in inflammation (P = 0.038) and re-epithelialization (P = 0.011) compared to the control. Regarding wound healing biomarkers, both HA gel and HA film groups showed lower level of COL1α1 expression on day 3 compared to the control. CONCLUSION: Within the limits of this study, HA film was found to be effective for oral wound healing, particularly for re-epithelialization. This finding suggests that HA film delivery can be beneficial not only for clinical convenience but also for promoting oral wound healing.