Effects of fluoride releasing cement on the selective removal of cervical carious dentin

应用牙科空气抛光机，在压力下喷射碳酸氢钠和水的研磨粉，去除颈部龋坏牙本质。本研究以硬度-深度曲线与牙本质中度龋软化模式相似的伪龋样病变为实验材料。通过调节抛光装置的研磨条件来选择性去除软化的牙本质是可行的。使用抛光装置（Airbrasion Group）或挖掘机（Excavation Group）去除表层后，将释放氟化物的粘固剂HY-BOND TEMPORARY CEMENT R（Shofu）应用于软化的牙本质剩余部分。气磨组软化牙本质的硬度比凿除组增加更多。实验结果表明，磨损组牙本质的抗脱矿能力较好，磨损组牙本质的抗拉强度与切削组牙本质的抗拉强度相比有显著性差异。使用两种修复材料，LITE-FIL II A（Shofu）作为复合树脂，FUJI IONOMER TYPE II LC作为玻璃离子水门汀。将LITE-FIL II A与粘合树脂IMPERVA FLUORO BOND R（Shofu）组合。磨损组中FUJI JONOMER II型LC的平均粘结强度为6.5MPa（*1.1），挖掘组中为4.9MPa（*1.5）。结论：空气抛光机在牙颈部龋蚀牙本质的选择性去除和修复治疗中具有重要的应用价值。

A dental air polishing unit that jets abrading powder of sodium bicarbonate and water under pessure was applied to removal of cervical carious dentin. Artficical caries-like lesions whose hardness-depth curve showed similarity to the softened pattern of the moderate dentin caries were used in this study as experimental materials. The selective removal of softened dentin by regulating abrasive conditions of the polishing unit was practicable.Fluoide releasing cement, HY-BOND TEMPORARY CEMENT R (Shofu) was applied to the softened dentin remaing after the removal of superficical layers using the polishing unit (Airbrasion Group) or a excavator (Excavation Group). More increase in hardness of softened dentin was showed in Airbrasion Group than Excavation Group. Abrasion Group showed that the remineralized dentin was refractory to the demineralization attack.The tensile bond strengths to the dentin were tested and compared Abrasion Group with Excavation Group. Two kinds of restorative materials, LITE-FIL II A (Shofu) as a composae resin and FUJI IONOMER TYPE II LC as a glass ionomer cement were used. LITE-FIL II A was combined with the bonding resin, IMPERVA FLUORO BOND R (Shofu). The avarage bond strength for FUJI JONOMER TYPE II LC was 6.5MPa(*1.1) in Abrasion Group and was 4.9MPa(*1.5) in Excavation Group. There was a significant difference between the two groups (p<O.05).In conclusion, it was suggested that the application of the air polishing unit was valuable to selective removal of cervical carious dentin and restorative treatment.