Background: Dental anxiety is a common issue affecting patients, often leading to the avoidance of essential dental treatments. Endodontic treatment, in particular, is associated with high anxiety levels due to its invasive nature. This study aims to assess the change in patient anxiety levels before and after endodontic treatment. Objectives: To evaluate the impact of endodontic treatment on patient anxiety levels using the Modified Dental Anxiety Scale (MDAS). Methods: A total of 35 patients requiring endodontic treatment participated in this study. Anxiety levels were measured using the MDAS at two points: prior to the procedure (pre-treatment) and immediately after the treatment (post-treatment). A paired t-test was used to analyze the reduction in MDAS scores. Results: Conclusion: The mean pre-treatment MDAS score was 14.3 (SD = 3.9), while the mean post-treatment score was 8.1 (SD = 3.2), showing a statistically significant reduction (p < 0.001). This indicates a marked decrease in anxiety following endodontic treatment. Endodontic treatment significantly reduces patient anxiety levels. Effective communication, pain management, and patient education are essential in managing dental anxiety. Future studies should focus on long-term anxiety outcomes and larger patient populations.