Clinical complications in the application of polyglycolic acid sheets with fibrin glue after resection of mucosal lesions in oral cavity

Evaluation of the Effects of Covering With Polyglycolic Acid Sheet on Wound Healing: A Pilot Histopathological Study

Purpose: Although the usefulness of polyglycolic acid (PGA) sheet for wound dressing has been recently reported, its histopathological effect on wound healing is not completely elucidated. This pilot study focused on the neo-epithelium formation and the remaining inflammation.

Methods: Full-thickness defects of 8 mm were created on the back of seven-week-old rats. Four rats were divided into the control (raw surface) group and the PGA group, in which the wounds were covered with a PGA sheet. The wounds were assessed on days seven and 12 after wound creation. The length of neo-epithelium on day seven was measured by referring to Masson’s trichrome (MT) and α-smooth muscle actin (α-SMA) staining. The remaining inflammation on days seven and 12 was assessed with ionized calcium-binding adapter molecule 1 (Iba-1) staining.

Results: The average values of neo-epithelium length on day seven measured by referring to the borderline between MT staining and α-SMA expression were 959.2 μm in the control group and 582.2 μm in the PGA group. The number of Iba-1-positive cells on day 12 was significantly higher in the PGA group than in the control group.

Conclusions: To assess the neo-epithelium length and the remaining inflammation, the α-SMA, MT, and Iba-1 staining may be appropriate.

Comparison of Postoperative Bleeding between Application of Polyglycolic Acid Sheet and Primary Closure in Tongue Cancer Patients with Partial Glossectomy

The technique of covering a mucosal defect with fibrin glue and a polyglycolic acid sheet (MCFP) for the resection of mucosa is applied in oral cancers. The MCFP technique for partial glossectomy provides faster relief from postoperative pain and the prevention of scar contracture, unlike primary closure. However, it has a major complication of postoperative bleeding. This study sought to compare postoperative bleeding between the MCFP technique and primary closure. We designed a retrospective study with a cohort of 57 patients who underwent partial glossectomy with the MCFP technique or primary closure. Our primary predictor variable was the wound closure procedure (primary closure or the MCFP technique). The primary outcome variable was postoperative bleeding, and the other variables were patient characteristics, excision area and depth, tooth contact for the wound, and antithrombotic therapy. Statistical evaluation was performed with Pearson’s chi-squared test, Welch’s t-test, and multiple logistic regression. P < 0.05 was considered statistically significant. The MCFP technique was selected for cases with a large excision area (1433 vs. 963 mm², P = 0.029). Total postoperative bleeding occurred in 10 of 57 patients (MCFP technique: 7 of 37 cases; primary closure: 3 of 20 cases). There was no significant difference in bleeding between the two groups (P = 0.71). Postoperative bleeding was significant in patients with antithrombotic therapy (MCFP: 40% vs. primary closure: 2%, P = 0.0024). Postoperative bleeding timing was significantly different in the MCFP technique (6.4 days) from that of primary closure (1 day; P = 0.0076). Postoperative bleeding was not associated with the MCFP technique or primary closure. However, postoperative bleeding with the MCFP technique occurred later than that with primary closure. The MCFP technique is not recommended for patients on antithrombotic therapy.

Dental Rehabilitation for Free Fibula Flap-Reconstructed Mandible with Scar Contracture: A Technical Note

Dental rehabilitation with osseointegrated implants in reconstructed mandibles is a common procedure, but the technique still requires improvement, especially in its reliability and technical simplification. We herein report dental rehabilitation of a free fibula-reconstructed mandible with scar contracture. A vestibuloplasty technique with application of a polyglycolic acid (PGA) sheet is described. The implants were inserted into a viable fibula flap with severe scar contracture of the overlying epithelium resulting from vascular instability in skin paddle. Only the fibula periosteum was sutured after implant insertion; exposed surfaces were covered with a combination of PGA sheet and fibrin sealant. The area with PGA sheet coverage gradually healed with moderate contracture. The epithelium around the almost implants became immobilized. The implant-supported removable partial denture with custom titanium bar was acceptable. Dental rehabilitation is possible for reconstructed mandibles with severe scar contracture. Application of a PGA sheet may be useful for vestibuloplasty in patients with reconstructed mandibles.