Effect of Titanium-Nitride Coating on the Wear Resistance of Stainless Steel Crowns

This study aimed to compare the wear resistance and surface characteristics of titanium-nitride coated crowns (TiNCs) with those of conventional stainless steel crowns (SSCs) under simulated masticatory conditions. TiNCs and SSCs for primary second molars were subjected to 200,000 cycles of wear using a chewing simulator under 50 N load with thermocycling. Volumetric wear was analyzed using three-dimensional scans before and after testing. Surface roughness and morphology were evaluated by field-emission scanning electron microscopy and atomic force microscopy. TiNCs exhibited significantly less volumetric wear than SSCs. After wear simulation, TiNCs maintained smoother and more uniform surfaces with fewer microdefects. The mean surface roughness was higher in SSCs than in TiNCs, and thermocycling alone influenced surface roughness. Compared with conventional SSCs, TiNCs exhibited superior wear resistance and surface characteristics. These findings suggest that TiNCs are a durable restorative option for primary molars under high functional stress, as their enhanced wear resistance and smoother surfaces may prolong restoration longevity and reduce replacement needs—particularly in children with parafunctional habits or strong occlusal forces.