Background <p>Clinical periodontal parameters are widely used to evaluate treatment outcomes in intrabony defects, but they do not directly reflect post-treatment radiographic trabecular texture changes. This retrospective longitudinal study aimed to evaluate clinical periodontal outcomes and radiographic trabecular texture changes using panoramic fractal analysis in intrabony defects treated with the entire papilla preservation technique.</p> Methods <p>This retrospective longitudinal study included patients with intrabony defects treated with the entire papilla preservation technique who had complete clinical records and panoramic radiographs at baseline, 6 months, and 1 year. Only biomaterial-free cases with isolated two- or three-wall intrabony defects were included. Fractal dimension (FD) values were calculated using ImageJ from standardized defect-side and reference regions of interest. Clinical periodontal parameters and FD values were compared over time using Friedman and Wilcoxon signed-rank tests, and exploratory associations between radiographic and clinical changes were assessed using Spearman correlation analysis.</p> Results <p>The median averaged defect-site FD increased significantly from 1.089 at baseline to 1.186 at 6 months and 1.240 at 1 year (<i>p</i> &lt; 0.001; Kendall’s W = 0.909). All pairwise comparisons were significant after Bonferroni correction (<i>p</i> &lt; 0.001). In contrast, reference region FD values did not change significantly (<i>p</i> = 0.417). Probing depth and clinical attachment loss also improved significantly over time (both <i>p</i> &lt; 0.001; Kendall’s W = 0.935), whereas gingival recession remained stable. No significant correlations were found between changes in averaged defect-site FD and changes in clinical periodontal parameters.</p> Conclusions <p>Within the limitations of this retrospective study, intrabony defects treated with an entire papilla preservation technique-based minimally invasive approach showed significant clinical improvement accompanied by an increase in defect-site FD values. Panoramic fractal analysis may provide complementary, non-invasive information on radiographic trabecular texture changes compatible with local trabecular reorganization after treatment, but should be considered an adjunct to clinical periodontal assessment rather than a substitute.</p> Trial registration <p>Not applicable. This was a retrospective observational study and did not require trial registration.</p>