In dentistry, particularly in posterior teeth with extensive caries or old restorations, the extension of restoration margins below the gingival level presents a significant clinical challenge. In such cases, restorative procedures become more complicated, periodontal health may be adversely affected, and long-term tissue loss can occur. To overcome this problem, the "Deep Margin Elevation" technique has been developed. This approach aims to raise subgingival margins caused by caries or fractures above the gingival level, thereby providing a healthier and more favorable foundation for successful treatment.

In this study, two different materials will be used for deep margin elevation, followed by restoration of the teeth with indirect restorations fabricated using additive manufacturing technology, which has become increasingly popular in recent years. Two different additive manufacturing resins will also be applied in the restorative phase. The teeth treated with deep margin elevation and indirect restorations will be evaluated at baseline, 6 months, and 12 months according to the FDI criteria, as well as periodontal parameters due to the involvement of the gingival region.

This study aims to highlight the importance of material selection in restorative treatment planning and to scientifically demonstrate the impact of the applied technique on surrounding tissues. Furthermore, it will provide an evidence-based perspective on how adopting a tissue-friendly approach during restorative procedures may contribute to favorable long-term outcomes.

Inclusion Criteria:

• Patients who apply to Mersin University Faculty of Dentistry between 01.12.2025 and 01.03.2026 for restorative treatment of their teeth
• Patients aged between 18 and 84 years
• Patients without parafunctional habits (such as bruxism, clenching, or foreign object chewing)
• Vital or non-vital molar and premolar teeth with a clinical indication for inlay/onlay restoration
• Teeth with deep cavities and margins located at or slightly below the gingival level
• Defects limited to the occlusal surface and one proximal surface
• Occlusal defects extending beyond one-third of the distance between fissure and cusp tip, including at least one cusp
• Posterior teeth with an indication for deep margin elevation without violation of the biologic width
• Teeth with opposing natural teeth or fixed prosthetic restorations
• Teeth with the presence of adjacent proximal contacts

Exclusion Criteria:

• Teeth with fractures or cracks
• Patients with temporomandibular joint disorders
• Patients with malocclusion, bruxism, or parafunctional habits
• Posterior teeth without opposing natural teeth or fixed prosthetic restorations
• Posterior teeth without adjacent proximal contacts
• Patients with a history of allergy to the components of the restorative materials used
• Patients with severe gingival enlargement, gingival recession, or active periodontal disease
• Teeth requiring deep margin elevation that present with non-physiological mobility, fistula, or periapical lesions