Association of flap tension with flap design and graft volume in soft tissue augmentation: a cadaveric study in pigs.

Purpose: This study was performed to evaluate the effects of flap design, grafting material, and graft dimension on flap tension and the initial volume increase achieved in soft tissue augmentation.

Methods: Six fresh porcine jaw cadavers were used in this study. Each side of the jaw was randomly assigned to receive either a standard split-thickness flap or a split-thickness flap with a palatal island. Following flap preparation, random allocation was employed to determine the order of 4 treatment modalities: 3 mm of a volume-stable collagen matrix (VCMX), 6 mm VCMX, 3 mm of a subepithelial connective tissue graft (SCTG), and 6 mm SCTG. Flap tension was measured and the wound was closed after the insertion of each specimen. Intraoral scans were taken before flap preparation and after closure to facilitate profilometric analysis.

Results: The palatal island flap exhibited significantly greater overall (=0.010) and crestal (=0.007) volume gains compared to the split-thickness flap, regardless of the use of VCMX or SCTG. The palatal island flap was associated with significantly lower flap tension force values (0.6 N; =0.035) than the split-thickness flap. Both materials (VCMX and SCTG) demonstrated comparable volume gains.

Conclusions: The findings of this cadaveric study indicate that the use of a palatal island flap effectively reduces flap tension. While both materials (VCMX and SCTG) yielded similar increases in volume, the palatal island flap demonstrated greater volume gains than the split-thickness flap for each grafting material.