Treatment of Ingrown Toenail with a Shape Memory Alloy Device.

Background: We sought to report the clinical results of a new conservative treatment modality that uses a shape memory alloy device in patients with ingrown toenail.

Methods: A retrospective review was performed on 41 patients with ingrown toenail treated with the K-D device (S&C Biotech, Seoul, South Korea) between April 2013 and July 2014. Recurrence rate, cosmetic results, pain during the treatment period, and patient satisfaction were the major outcome measures.

Results: Patients were followed for at least 6 months (mean ± SD, 8.6 ± 2.1 months; range, 6-12 months). Recurrence was seen in eight patients (19.5%). Mean time to recurrence was 6.2 months (range, 3-10 months). Thirty-one patients (75.6%) were satisfied with the treatment. Thirty-five patients (85.4%) rated the application and treatment period as painless, and the remaining six (14.6%) noted pain particularly during shoe wearing. Thirty-one patients (75.6%) rated the cosmetic results as "excellent," four (9.8%) as "acceptable," and six (14.6%) as "poor." Satisfaction with the treatment, the cosmetic results, and pain were significantly worse in patients with recurrence (P = .0001 for all). All of the patients returned to their work immediately after application of the device. No complications occurred.

Conclusions: The K-D device is a safe and effective treatment method for ingrown toenail. Although the recurrence rate is higher than for surgical treatment methods, the K-D device is a practical and painless method that provides immediate return to work and daily activities and excellent or acceptable cosmesis in most patients.