Background: Onychocryptosis is one of the most prevailing onychopathies and one of the usual reasons for visiting podiatry clinics. In this research, we aim to evaluate the effectiveness of a procedure of nail reeducation technique via a strip of polyethylene in subjects with stage I or IIa onychocryptosis, in which pathological toenail curves are present. Methods: This research was a randomized clinical trial (ACTRN12615000834550). The sample was made up of 94 cases of stage I or IIa onychocryptosis, according to the Mozena classification. Briefly, 46 cases were treated with the combination of a spicule technique and nail brace with a polyethylene plastic strip, and 48 were only treated with the spicule technique. Results: The combination of the spicule technique and the nail brace technique with a strip of polyethylene had a significantly lower recurrence rate compared to that achieved with just the spicule technique, twelve months after the beginning of the study (N.S. = 0.000 for α = 0.05). The change in the nail width achieved with the nail brace technique, twelve months after the beginning of the study, was statistically significant (N.S. = 0.000 for α = 0.05). Conclusions: The recurrence rate of the spicule technique alone was significantly higher than the combined technique of spicule with nail brace. A nail brace with a strip of polyethylene reduces the recurrence rate of onychocryptosis.