Radiographic assessment of the relationship between alveolar bone loss and overhanging margins of posterior dental restorations in diabetic patients: a retrospective study.

OBJECTIVE

As no previous study has focused on the effect of overhanging restorations on alveolar bone loss in diabetic and non-diabetic individuals, this study aimed to compare alveolar bone loss between these groups using panoramic radiographs.

METHODS

A total of 212 patients (106 diabetic, 106 non-diabetic) who met the inclusion criteria were retrospectively selected from panoramic radiographs taken between January 2023 and July 2025 at Inonu University Faculty of Dentistry. Marginal bone loss adjacent to overhanging restorations was measured as the distance between the cementoenamel junction (CEJ) and the alveolar crest, with contralateral intact or solely occlusally restored teeth serving as controls. All measurements were performed by a restorative dentistry specialist, and intra-observer reliability was confirmed (Cohen's Kappa > 0.80). Data were analyzed using appropriate parametric and non-parametric statistical tests, with a significance level set at p < 0.05.

RESULTS

Overhanging restorations were more frequently observed in molars compared with premolars and on distal surfaces compared with mesial surfaces. No significant difference in alveolar bone loss was found between amalgam and composite restorations. The levels of alveolar bone loss were significantly higher in diabetic patients compared to non-diabetic individuals; the median CEJ-crest distances on the sides with overhanging restorations were 2.71 mm and 2.07 mm, respectively (p < 0.001), while on the contralateral control surfaces, they were 1.76 mm and 1.44 mm, respectively (p = 0.003).

CONCLUSION

Overhanging restorations are associated with increased alveolar bone loss, and this effect was significantly greater in diabetic patients. These findings highlight the importance of detecting and correcting overhanging restorations, particularly in patients with systemic risk factors such as diabetes, to prevent periodontal destruction.