Deep Margin Elevation and Its Influence on Periodontal Health and the Longevity of Indirect Restorations—A Scoping Review

OBJECTIVE: To map and assess the current evidence regarding the impact of deep margin elevation (DME) on periodontal health and the mechanical properties of indirect restorative materials, highlighting existing gaps and future research directions. MATERIALS AND METHODS: This study followed PRISMA-ScR guidelines for scoping reviews and was registered on the Open Science Framework platform. A systematic search was conducted in April 2025 using PubMed/Medline, Embase, Scopus, and ISI Web of Science databases, as well as gray literature, without language or date restrictions. Any level of evidence evaluating indirect restorations in posterior teeth using DME with resin or ceramic materials was included. A descriptive analysis was performed. RESULTS: A total of 26 studies were included in the analysis: 12 in vitro, eight clinical, and six reviews. Clinical evaluations focused primarily on plaque index, bleeding on probing, and probing depth. Most clinical studies indicated that DME did not adversely affect periodontal health when supracrestal attachment was maintained. However, a 12-year longitudinal study found that 50% of cases had bleeding on probing and 11% had periodontal complications, including bone loss. Bulk-fill resin-based composites were the predominant material studied in DME, while ceramic crowns were the most commonly used final restorations in the posterior region. CONCLUSIONS: Current evidence on DME reveals inconsistencies in clinical outcomes and important methodological limitations, particularly regarding periodontal health. Laboratory findings suggest that the use of a low-modulus interlayer may improve stress distribution and enhance restoration strength, but clinical validation remains limited. CLINICAL SIGNIFICANCE: Effective management of DME is critical in clinical practice to reduce periodontal complications and improve restoration longevity. This includes respecting the supracrestal insertion and selecting materials that promote both periodontal health and restoration durability.