## 1 Introduction  
There are several treatment methods for the treatment of an unguis incarnatus ingrown nail, which range from non-invasive conservative treatment: pharmacotherapy, tamponade, protective tubes, orthonyxic buckles, and taping, to extensive surgical procedures: wedge resection using the Quenu method, the Zadik procedure, and the procedure according to [PERSON] and Steindler [1; 2; 3]. Several factors have been proposed as contributory to the occurrence or worsening of ingrown toenails with varying degrees of evidence. These include poor nail-cutting technique, cutting the nails too short or not cutting the nails straight, hyperhidrosis, ill-fitting footwear, nail deformity, trauma, excess internal pressure caused by over curvature of the nail plate, arthritis, skeletal abnormalities, diabetes, obesity, and peripheral edema [3].  
Although with surgical treatment one can achieve quick results by completely removing the ingrown nail or the tissue surrounding it, it should be borne in mind that these measures are invasive and may lead to deformation of the nail plate at a later stage of growth. Complications following surgical interventions can include significant post-operative pain, prolonged wound healing, the risk of bone infections or other infections, and a longer recovery period compared to conservative methods. However, there is no consensus on the ideal first-choice treatment; the choice of therapy depends on the etiology, clinical picture, and ingrowth stage. To avoid convalescence-requiring surgical treatment, it is worth considering alternative methods if the nail condition is not a contraindication [3,4].  
Developed classification systems for ingrown toenails serve as the basis for treatment decisions. The most commonly used classification is based on age, and most of them focus on the severity of ingrown nails in three stages: from mild (stage I) to severe (stage III). Youth ingrowth affects children and adolescents but can also occur in mature individuals. It is characterized by a flat nail plate, deeply embedded in the fleshy nail walls. Adult ingrowth mainly affects mature and elderly people and is characterized by an arched nail plate with a tendency to roll [5,6].  
A more precise five-point classification according to [PERSON] is also used, with a letter designation, where \"a\" always means one-side discomfort, while \"b\" means ingrowth on both sides, i.e., the nail grows in from the lateral side and the medial part. Stage 1a/1b means the initial stage of an ingrown nail, with no inflammatory symptoms and little or no pain. Stage 2a/2b--pain with inflammatory symptoms. Stage 3a/3b--purulent inflammation and increased pain. Stage 4a/4b--paronychia and hypergranulation (caro luxarians); patients feel severe pain. Stage 5a--status post-operation with recurrent complaints, i.e., the nail continues to grow inward. It involves significant pain. Stage 5b--status post-surgery; severe soreness due to a \"snag\" as a result of incomplete removal of the matrix [3, 4, 5, 6].  
Innovative treatment involves removing the ingrown part of the nail and installing an orthonyxic buckle, which, with appropriate tension, orients the nail plate so that the nail can grow in the right direction without causing any discomfort. The aim of this paper is to evaluate the efficacy of the VHO-Osthold(r) Perfect orthonyxic buckle while treating ingrown nails requiring pediatric care. The following research questions were formulated. What will the effects in the clinical picture of the nail apparatus be after the application of the VHO-Osthold(r) Perfect buckle? What will the number of applications, full treatment time, and therapeutic effect of the VHO-Osthold(r) Perfect buckle be? What factors predispose to ingrown nails? Will the buckle affect the subjects' quality of life scores before and after application?