Grey areas in restorative dentistry: part 5. Mind the gap 2: the restoration with a deficient margin

Restorations, whether direct or indirect, may display clinically detectable gaps between themselves and tooth tissue, i.e. deficient margins. These deficiencies may arise from degradation of the material over time or may be deficient from the outset, such as fitting an indirect restoration with suboptimal marginal adaptation. The most frequently cited reasons for the replacement of restorations are recurrent caries, fracture of the restoration, marginal deficiency, lack of a contact point, and occlusal discrepancy, and of these, the clinical diagnosis of secondary caries is the most common. The diagnosis of recurrent caries at the margins of restorations is difficult and liable to misinterpretation leading to perhaps unnecessary remedial work. CPD/Clinical Relevance: ‘Failing’ restorations are commonly seen in dental practice and pose unique challenges to the dental practitioner in terms of their management.