不同增稠载体的过氧化脲漂白剂对釉质表面形态的影响

The effects of carbamide peroxide bleaching agents with different thicking carriers on enamel surface morphology

目的:研究不同载体和浓度的过氧化脲(carbamide peroxide,CP)漂白剂对釉质表面形态的影响。方法:分别以Carbopol、PVP、Poloxamer为凝胶增稠载体,配制含100g/L、150g/L和200g/LCP的CP漂白剂(pH6.5)和不含CP的凝胶制剂,利用近期拔除的离体前牙牙冠分组观察CP漂白剂对釉质表面形态的影响。结果:以Carbopol,PVP或Poloxamer作为增稠载体的漂白剂,随着CP浓度的增高,釉质表面从轻度溶解、脱矿,蜂窝状改变,直至正常釉质层消失,"鱼鳞状"的釉柱结构清晰可辨。其中以Poloxamer为增稠载体的漂白剂较之更甚。结论:以Carbopol,PVP或Poloxamer作为增稠载体的漂白剂,随着CP浓度的增高,釉质表面出现不同程度的形貌改变。

AIM ： To study the effect of carbamide peroxide （CP） bleaching agents of different concentration and carrier on enamel surface morphology. METHODS： Using Carbopol, PVP or Poloxamer as thickening carrier respectively, we applied bleaching gels （pH6.5） containing 10% , 15% and 20% of CP and gels without CP on the ena mel specimens for 2 weeks （6 -8h/d, 37℃,100% relative humidity）, then evaluated the changes of enamel surface morphology. RESULTS： With carbopol, PVP or poloxamer as thicking carriers respectively, when the carbamide peroxide concentration increased in the bleaching gel, the enamel surface alterations varied from mild dissolution, demineralization to etchinglike appearance; the fish- scale- like enamel rods were often clearly exhibited when the ena mel structure was changed by dissolution of its majority inorganic substance. Among the CP bleaching agents, the gel with poloxamer as thickening carrier caused the most significant changes on the enamel surface. CONCLUSION： With Carbopol, PVP or Poloxamer as thickening carrier, carbamide peroxide bleaching agents cause different levels of enamel surface changes as the CP concentration increases.