Mandava Pragna, Bolla Nagesh, Thumu Jayaprakash, Vemuri Sayesh, Chukka Sunil
Senior Lecturer, Department of Conservative Dentistry and Endodontics, SIBAR Institute of Dental Sciences , Guntur, Andhra Pradesh, India .
Professor and HOD, Department of Conservative Dentistry and Endodontics, SIBAR Institute of Dental Sciences , Guntur, Andhra Pradesh, India .
J Clin Diagn Res. 2015 Feb;9(2):ZC43-6. doi: 10.7860/JCDR/2015/11071.5595. Epub 2015 Feb 1.
The importance of the retrograde cavity preparation and the material used to restore is of utmost importance to achieve successful surgical endodontics.
The aim of the present study is to evaluate the apical micro-leakage of root end cavities filled with Mineral trioxide aggregate, Biodentine and light cure GIC using two different cavity preparation techniques that is conventional bur preparation and ultrasonic tip preparation.
Eighty extracted single rooted human teeth (except mandibular incisors) with one canal, fully developed apices and without any major carious lesion are collected for the study. The teeth were sectioned at CEJ to standardize the length. Roots are instrumented upto master apical file 40 K size and obturated with gutta percha and AH plus sealer in lateral condensation technique. The teeth were then resected apically at 90° angle axis to the long axis of the root removing 3 mm of the apex. The teeth were divided in to four groups of 20 each- • Group I- samples restored with MTA. • Group II- samples restored with Biodentine. • Group III- (Positive control group)- samples restored with Light activated GIC. • Group IV - (negative control group)- no filling material. Each group is divided into two subgroups (a, b) of ten teeth each 1. Retropreparation done with ultrasonic retrotip. 2. Retropreparation done with conventional bur. The teeth were then immersed in 0.5% Rhodamine B dye for 48 h. The teeth were split longitudinally and the interface between the restored material and the canal wall is observed under Confocal laser scanning microscope. Depth of dye penetration was examined under stereomicroscope.
The statistical analysis was performed by One way ANOVA, t test. Pair wise comparision was done by Newman - Keuls multiple post hoc test. The mean values of Dye penetration for Group Ia (321.23), Group Ib (490.11), Group IIa (1065.14), Group IIb (1170.96), Group IIIa (1888.90), Group IIIb (2025.35). The samples prepared with ultrasonic retrotip showed less microleakage but it is statistically not significant.
MTA showed significantly less microleakage when compared to Biodentine and light cure GIC and there is no statistical difference between the ultrasonic retrotip preparation and conventional bur preparation.
逆行性窝洞预备以及用于修复的材料对于成功进行牙髓外科手术至关重要。
本研究的目的是使用两种不同的窝洞预备技术,即传统车针预备和超声尖预备,评估用三氧化矿物凝聚体、生物陶瓷和光固化玻璃离子水门汀充填的根尖窝洞的根尖微渗漏情况。
收集80颗拔除的单根人牙(下颌切牙除外),均为单根管,根尖完全发育且无任何严重龋损,用于本研究。在牙颈部釉牙骨质界处将牙齿截断以标准化长度。根管预备至40 K号主尖锉,并采用侧向加压技术用牙胶尖和AH plus封闭剂进行充填。然后将牙齿沿与牙根长轴呈90°角的方向在根尖处切除3 mm根尖。将牙齿分为四组,每组20颗:
• 第一组 - 用MTA修复的样本。
• 第二组 - 用生物陶瓷修复的样本。
• 第三组 - (阳性对照组) - 用光固化玻璃离子水门汀修复的样本。
• 第四组 - (阴性对照组) - 不使用充填材料。
每组再分为两个亚组(a、b),每组10颗牙:
用超声倒锥钻进行倒预备。
用传统车针进行倒预备。
然后将牙齿浸入0.5%的罗丹明B染料中48小时。将牙齿纵向劈开,在共聚焦激光扫描显微镜下观察修复材料与根管壁之间的界面。在体视显微镜下检查染料渗透深度。
采用单因素方差分析、t检验进行统计分析。采用纽曼 - 基尔斯多重事后检验进行两两比较。第一组a(321.23)、第一组b(490.11)、第二组a(1065.14)、第二组b(1170.96)、第三组a(1888.90)、第三组b(2025.35)的染料渗透平均值。用超声倒锥钻制备的样本微渗漏较少,但在统计学上无显著差异。
与生物陶瓷和光固化玻璃离子水门汀相比,MTA的微渗漏明显较少,并且超声倒锥钻预备和传统车针预备之间无统计学差异。