Secured Anatomy-Driven Flap Extension (SAFE) for Guided Bone Regeneration: A Modified Flap Release Technique Description and Retrospective Study
Current flap-releasing designs for guided bone regeneration (GBR) emphasize preserving subperiosteal microvasculature by adapting a deep-slit approach, separating the periosteum from the flap. Although biologically sound, a biomechanical disadvantage may be encountered. This study aimed to describe a modified design, the Secured Anatomy-driven Flap Extension (SAFE) technique, for effective facial flap release and to preliminarily evaluate the clinical outcomes of this technique retrospectively. Chart reviews were conducted to identify patients treated by facial flap release in staged GBR procedures between May 2020 and March 2022. The anatomical, biological, and biomechanical rationale of this technique were described. The following clinical data were collected: intraoperative and postoperative complications, initial and final horizontal ridge width before and 5–6 months after the GBR, and implant performance. A total of 10 patients were identified. At baseline, these patients presented with a mean ridge width of 2.05 ± 0.52 mm. No intraoperative and postoperative complications were observed in these patients (bleeding, wound opening, neurosensory disturbance, etc.) at the 2–3-week follow-up visit. At the re-entry, a mean ridge width of 6.50 ± 0.55 mm was measured (P < .01), resulting in a mean of 4.45 ± 0.65 mm ridge width gain. Twenty-one implants were successfully placed, integrated, and in function without signs/symptoms of peri-implantitis after a mean 21.5 ± 9.2 months follow-up period. Preliminary results suggest that the SAFE technique is a safe and predictable approach for releasing facial flaps during GBR procedures.
Step-by-step illustration of the SAFE technique. (a) incision, (b) full-thickness flap reflection in Region 1, (c) layered partial thickness dissection in Region 2, (d) tunneling in the adjacent dentate region, (e) waving motion for muscle detachment in Region 3, (f) selective sharp dissection.
A case presentation was shown. (a) The initial clinical presentation and (b) cone-beam computerized tomography (CBCT) of the edentulous ridge #7 and #8. (c) Upon surgical exposure, the severely deficient ridge was confirmed. (d) The wound was closed with 7–0 polypropylene sutures. (e) Postoperative CBCT showed satisfactory ridge augmentation, followed by surgical re-entry for implant placement at 6 months (f).
Another case with (a) initial occlusal view of the severely deficient ridge on the left posterior mandible and (b) 2-week healing after GBR. The wound was fully closed without revealing the incision line or signs/symptoms of complications, such as infection. Note: Image 3b was directly extracted from a short video included in Supplement Data.
Cross-sectional anatomical image of an edentulous ridge with ultrasonography. The images show a facial cross-sectional view of the raw ultrasound b-mode (brightness), blood flow images, and annotations. The flap dissection was done in different locations depending on the anatomical region. The key difference from the other designs is that the dissection at Region 3 is superficial to the muscle layer, so the muscle is not included in the flap.
Contributor Notes