Introduction: The quality of the surgical cut depends largely on the sharpness of the scalpel blade, which tends to wear down progressively when it comes into contact with soft tissues such as the gum.

Objective: To analyze the association between the wear of the scalpel blade (size 15) and its impact on clinical performance during surgical procedures. 

Materials and methods: An experimental, descriptive, and comparative study was conducted. The sample consisted of 980 scalpel blades used on patients undergoing third molar extractions. The blades were grouped according to their frequency of use (0, 1, 2, 3, 4 times). Cutting quality and wear were identified by measuring the blade diameter, total length of microfractures, and number of microfractures, as verified by scanning electron microscopy (SEM). Statistical analysis was performed using ANOVA with Tukey's test (P ≤ 0.05). 

Results: A decrease in optimal cuts was confirmed starting with the third use of the scalpel blade, with a progressive increase in poor cuts. Furthermore, when comparing the groups, a significant variation was observed with and without use in the cutting edge diameter, total microfracture length, number of microfractures, and clinical cutting capacity (p-value < 0.05). 

Conclusions: It is evident that with increased use of the No. 15 scalpel blade, clinical cutting capacity decreases, the cutting edge diameter increases, and the microfracture length increases. For this reason, to maintain clinical conditions of the incision during third molar extraction, the scalpel blade can be used up to three times.