Oxidative stress (OS) has gained substantial relevance due to its involvement in the pathogenesis of numerous systemic diseases. It is characterized by an imbalance between the production of reactive oxygen species (ROS) and the capacity of endogenous antioxidant systems to neutralize them. Various factors, including trauma, immunological alterations, and psychological stress, may contribute to this condition. The aim of this narrative review was to analyze OS markers and total antioxidant capacity (TAC) in asymptomatic and pericoronitis-associated impacted mandibular third molars (ITMs). This review examines the relationship between OS and impacted ITMs, highlighting the importance of timely clinical management to prevent chronic tissue damage. Current evidence indicates that OS biomarkers such as myeloperoxidase (MPO), malondialdehyde (MDA), uric acid (UA), and nitric oxide (NO) are elevated in patients with ITMs, including those classified as asymptomatic, and that a reduction in total antioxidant capacity (TAC) has been observed. The surgical removal of ITMs can effectively reduce OS levels. Following the procedure, oxidative markers typically return to normal within a relatively short period of time, and there is often a significant improvement in TAC.