Background <p>This study aimed to assess dentin radiodensity, the bond strength of various root canal sealers, and the elemental distribution at the dentin–sealer interface in both healthy and diabetic teeth.</p> Methods <p>Ninety-six extracted teeth from diabetic and healthy individuals were included. Radiodensity of root dentin was measured using cone beam computed tomography and quantified via Hounsfield Unit (HU) values. Samples were divided into six groups: diabetic or healthy teeth treated with one of three sealers (Total Fill BC Sealer Hi Flow, BioRoot RCS, or AH Plus). Root canal treatment was applied to all teeth. A 1-mm-thick mid-root section was obtained from each sample. Push-out bond strength testing was conducted on half of the samples to measure adhesion (in MPa), while the other half were analyzed using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) to examine the elemental composition at the dentin–sealer interface.</p> Results <p>Although HU values were found to be lower in diabetic teeth, the difference was not statistically significant (<i>p</i> &gt; 0.05). Push-out tests revealed significantly lower bond strength in diabetic teeth compared to healthy ones (<i>p</i> &lt; 0.05). However, the choice of root canal sealer did not significantly influence bond strength (<i>p</i> &gt; 0.05). SEM-EDS results indicated that the elemental composition of the interfacial layer was influenced more by the sealer type than by diabetic status.</p> Conclusions <p>Diabetes did not significantly affect dentin radiodensity, but it was associated with lower bond strength between dentin and sealers.The chemical composition of the root canal sealer plays a key role in interfacial interactions, influencing the elemental characteristics of the bonding interface.</p>