Lower Facial Rejuvenation Using Absorbable Casting Barbed Thread
Sixty-one patients were enrolled (3 men and 58 women), all of whom had a rating of 3 or 4 on the Wrinkle Severity Rating Scale (WSRS). Our study was performed under the approval of the institutional review board. We performed a 24-week, single-center, single-arm, pre-post test design, open clinical study among these patients with deep nasolabial folds and lower facial drooping.
The provided absorbable casting barbed suture is the first polydioxanone-based, absorbable, barbed suture by noncutting technology. It contains multiple, diversified, bidirectional barbs on both sides to grab and secure the soft tissue that needs to be remodeled (Figure 1).
All procedures were performed under monitored anesthetic care with local anesthesia (0.5% lidocaine hydrochloride with 1:100,000 epinephrine) and tumescent solution infiltration (1 mL epinephrine 1 mg/mL, 1 ample hyaluronidase 1,500 IU, 50 mL lidocaine 2% 20 mg/mL, 12.5 mL sodium bicarbonate 8.4% 1.68 g/20 mL, and normal saline 1 L).
The exit points were designated on a straight line, which connected the alar base and the angle of the mandible (Line I). We also drew 2 horizontal, parallel lines, 1 from the alar base (Line II) and another from the oral commissure (Line III). Then, we supposed 4 points. The point of intersection between Lines I and III was named Point B, the midpoint between the alar base and Point B was Point A, the angle of the mandible was Point D, and the midpoint between Point B and D was Point C (Figure 2).
The efficacy and safety of the procedure were evaluated using several scales: (1) comparison of the distance from a baseline to some given points (before procedure and immediately after procedure), (2) degree of improvement in the WSRS score on the 4th, 8th, and 24th weeks as evaluated by the operator and the independent evaluator, (3) degree of improvement in the GAIS (Global Esthetic Improvement Scale) score on the 24th week as graded by the operator and the patients, and (4) complications during the study. Statistical analyses included the paired t-test, Wilcoxon signed rank test, and McNemar test.
The effectiveness of the procedure was evaluated according to several categories. First, immediate differences in the distance between given points (before procedure and immediately after procedure) were checked. On the right side, the difference was 0.41 ± 0.20 cm for Point A, 0.83 ± 0.23 cm for Point B, 0.78 ± 0.24 cm for Point C, and 0.48 ± 0.25 cm for Point D. On the left side, the difference was 0.42 ± 0.24 cm for Point A, 0.81 ± 0.20 cm for Point B, 0.79 ± 0.15 cm for Point C, and 0.49 ± 0.29 cm for Point D (Figure 2). There were improvements on all points, and Points B and C especially showed a remarkable lifting effect (Figure 3).
The preoperative baseline WSRS, as measured by the operator, was 3.21 ± 0.41. The degree of improvement in the WSRS was −1.23 ± 0.42 on the 4th week, −1.25 ± 0.43 on the 8th week, and −1.16 ± 0.37 on the 24th week. The baseline WSRS and the degree of improvement of the WSRS, as measured by the independent evaluator, were 3.30 ± 0.45 (baseline), −1.56 ± 0.43 (4th week), −1.