<p>This retrospective observational study aimed to investigate whether controlled hypertension (HT) is associated with radiographic periapical healing after single-visit non-surgical endodontic retreatment (Re-RCT) compared with systemically healthy individuals. Two groups were formed according to predefined inclusion and exclusion criteria (<i>n</i> = 22). The HT group consisted of periapical radiographs from 22 teeth of 22 patients (mean age 53.31 ± 9.22 years; 10 females, 12 males) with no systemic diseases other than controlled HT, while the control group included 22 teeth of 22 systemically healthy patients (mean age 41.68 ± 12.13 years; 16 females, 6 males). All teeth were single-rooted mandibular premolar teeth with apical periodontitis that underwent single-visit Re-RCT and had a minimum radiographic follow-up of six months. Radiographic periapical status was evaluated using the Periapical Index (PAI), and lesions were additionally assessed by quantitative measurement of the periapical lesion size. Appropriate statistical tests, including multivariable logistic regression, were used to compare periapical healing and treatment success between the two groups and identify potential prognostic factors. The results demonstrated no statistically significant difference in radiographic periapical healing and re-RCT success between HT patients and healthy individuals (<i>p</i> &gt; 0.05), whereas a smaller preoperative lesion size was associated with a higher probability of complete healing. These findings suggest that, under adequate medical control, HT alone does not adversely affect periapical healing after single-visit Re-RCT and contributes to a better understanding of the prognosis of Re-RCT in patients with controlled HT.</p>