Influence of masticatory fatigue on the fracture resistance of the pulpless teeth restored with quartz-fiber post–core and crown

Daily chewing has no effect on the fracture toughness of quartz-fiber tooth restoration materials, according to recent research from China. Chun-Yuan Zhang from Sun Yat-Sen University and colleagues investigated how extracted molars — that had been repaired with aligned quartz-fiber ‘posts’ in an epoxy matrix — behave under two kinds of destructive force. They found that molars subjected to five years’ worth of chewing motions through cyclic force loading had identical fracture points and patterns as molars under a static, steadily increasing force. Zhang and colleagues attribute the resilience of the quartz posts to biomechanical movements that allow homogenous transfer of stress into tooth dentin. Chemically enhanced bonding of the quartz posts to teeth and structural reinforcements also contributed to the sturdiness of this novel system.