Purpose: Since flap advancement is a prerequisite for tension-free primary closure and successful regenerative procedures, the aim of this study was to test the efficacy of six surgical approaches for flap advancement in an ex vivo porcine model.
Materials and methods: A total of 60 fresh mandibles from pigs were randomized into one of six groups: (1) trapezoidal full-thickness flap design with two vertical releasing incisions (control), (2) trapezoidal flap with linear periosteal scoring, (3) mucosal detachment technique, (4) mucosal detachment with horizontal extension, (5) mucosal detachment with horizontal and vertical extension, and (6) mucosal detachment with horizontal vertical and cutback extension. Coronal advancement of the flap was recorded as the primary variable; the surface area of exposed mucosa and the tear strength were recorded as secondary variables.
Results: Homogeneity existed among groups for preoperative keratinized tissue width and tissue thickness. Mucosal detachment with horizontal, vertical, and, cutback extensions achieved the highest amount of advancement. All remaining groups achieved a statistically higher advancement compared with the trapezoidal full-thickness flap (control). Pairwise comparison demonstrated statistical significance between any two groups (P < .001). A positive correlation was noted between exposed mucosa and flap advancement; the advancement increased 0.62 mm for each 10 mm2 of increase in the exposed mucosal surface. Strength at tear stress was the highest in the trapezoidal full-thickness flap (control) and mucosal detachment with horizontal-vertical-cutback incisions (P < .001).
Conclusion: Coronal flap advancement was maximized in the mucosal detachment techniques and positively correlated with the area of exposed mucosa.