Assessing the Longevity of Zirconia-Based Crowns in Bruxism Patients

ABSTRACT Background: Bruxism is a parafunctional habit that often leads to excessive wear and tear of dental restorations. Zirconia-based crowns are increasingly used due to their superior mechanical properties and esthetic advantages. Materials and Methods: A total of 80 patients (ages 25–60) with diagnosed bruxism were selected for the study. Each patient received at least one zirconia-based crown. The crowns were fabricated using CAD/CAM technology and cemented with resin-based luting cement. Patients were divided into two groups: Group A (40 patients) received zirconia crowns with occlusal guards, and Group B (40 patients) received zirconia crowns without occlusal guards. The crowns were evaluated for longevity and clinical performance using criteria such as crown retention, fracture, marginal integrity, and wear on the opposing dentition. Results: At the end of 5 years, 92% of crowns in Group A and 80% in Group B remained functional without any major complications. Crown fractures occurred in 8% of Group A patients and 20% of Group B patients. Marginal integrity was well-maintained in 95% of Group A crowns and 85% of Group B crowns. Wear on the opposing dentition was minimal in both groups, but slightly higher in Group B. The use of occlusal guards significantly improved the longevity of the crowns (P < 0.05). Conclusion: Zirconia-based crowns exhibit high longevity in patients with bruxism, particularly when used in conjunction with occlusal guards.