二氧化氯作为根管超声冲洗剂的清洁效果

Cleaning Effectiveness of Chlorine Dioxide Soluation Used as Root Canal Ultrasonic Irrigant

目的评价二氧化氯用作根管超声冲洗剂的清洁效果。方法选择30颗离体单根管前磨牙,截去牙冠后随机平分成A、B、C三组,用手持不锈钢器械逐步后退法进行根管预备,超声波冲洗,冲洗剂分别为蒸馏水、1.0%次氯酸钠和0.1%二氧化氯溶液。完成根管预备后纵行劈开牙根,扫描电镜观察,在根管颈1/3、中1/3、尖1/3各部位随机拍照,在电镜照片上评定根管壁上碎屑和玷污层记分,计数牙本质小管开放数目,并进行统计学分析。结果A、B、C各组碎屑记分差异无统计学意义(P>0.05);B、C两组的玷污层明显少于A组,差异有统计学意义(P<0.01);牙本质小管开放数也明显多于A组,差异有统计学意义(P<0.01),但B、C两组之间差异无统计学意义(P>0.05)。结论0.1%二氧化氯溶液用作根管超声冲洗剂,具有良好的清洁作用,对碎屑和玷污层的去除能力不亚于1.0%次氯酸钠,明显优于蒸馏水。

Objective To evaluate the cleaning effectiveness of chlorine dioxide soluation used as root canal ultrasonic irrigant. Methods Thirty recently extracted premolars with a single root canal were divided into three equal groups after cut crown （ A, B, C）. All root canals were instrumented by hand with stainless steel endodontie instruments using a conventional step back technique, and irrigated by ultrasond using distill water （group A）, 1.0% NaOCl （group B）, 0.1% ClO2 （ group C）. All roots were split longitudinally and prepared for SEM observation, the presence of debris and smear layer was evaluated, the numbers of visible open dentinal tubules were counted respectively from photomicrographs taken in the apical, middle and cervical thirds of the canals, and the mean scores and numbers were compiled separately. Values obtained were tabulated and statistical analysis was carried out using One-Way ANOVA. Results Statistical analysis showed that there was no significant difference among the three groups for debris （P〉 0.05）, but there was significant difference among the three groups for smear layer and the numbers of visible open dentinal tubules （ P 〈 0.01 ）, both group B and group C had significantly less smear layer （ P 〈 0.01 ） and mere visible open dentinal tubules compared with group A （ P 〈 0.01 ）, but group B had no significant difference in smear layer and the numbers of visible open dentinal tubules from group C （ P 〉 0.05）. Conclusion Chlorine dioxide has a good cleaning effectiveness used as ultrasonic irrigant of root canals during preparation, the cleaning ability of 0.1% ClO2 to debris and smear layer is better than using distill water, similar to that of 1.0% NaOCl .