Comparison of vertical releasing incisions and horizontal extending incisions for periodontal accelerated osteogenic orthodontics in the anterior region: a randomized controlled trial with clinical and radiographic outcomes.

BACKGROUND

Periodontal accelerated osteogenic orthodontics (PAOO) requires precise flap design for aesthetic preservation, functional stability, and rapid recovery. This study compared two additional flap incisions—vertical releasing incision (VRI) and horizontal extending incision (HEI) for PAOO in the anterior region.

METHODS

Twenty-two orthodontic patients requiring PAOO were randomized into the VRI or HEI group. Immediately after surgery, the surgical time and graft material weight were recorded. Wound healing was evaluated at 1 and 2 weeks post-surgery. Soft-tissue parameters, such as probing depth (PD), clinical attachment level (CAL), keratinized gingival width (KGW), and gingival recession depth (GRD), were assessed at baseline, 3, 6, and 12 months. To assess hard-tissue changes, including root length, vertical bone level (VBL), and bone width measured at 2 mm (BW2), 4 mm (BW4), and 6 mm (BW6) below the cemento-enamel junction (CEJ), cone beam computed tomography (CBCT) scans were performed at baseline, 6, and 12 months. Lateral cephalometric analysis was performed to evaluate tooth movement before and after orthodontic treatment.

RESULTS

Patient-level analyses revealed that the HEI technique had shorter surgical time (57.66 ± 5.01 min vs. 68.50 ± 13.50 min, p = 0.029) and a lower incidence of scarring (10% vs. 60%) than VRI. At the tooth-level, HEI achieved significantly greater labial bone width (BW2, BW4, BW6; all p < 0.001). Both groups showed comparable KGW increases (VRI: 0.71 ± 1.15 mm; HEI: 0.85 ± 1.13 mm) and VBL changes (VRI: 2.94 ± 2.79 mm; HEI: 2.69 ± 2.96 mm) at 12 months. No significant differences were observed between the groups regarding postsurgical pain or mucosal condition.

CONCLUSIONS

Both flap techniques were effective in improving KGW and bone augmentation (VBL, BW2, BW4, BW6), with HEI showing advantages in terms of surgical time, reduced scar formation, and greater bone width in PAOO surgery. TRIAL REGISTRATION: Registered on clinicaltrial.gov; NCT05441683, 13/6/2022.