ABSTRACT
Background: Cleaning and shaping the root canal is an important phase in endodontic therapy. A prepared root canal should have a shape that flares from apical to coronal regions, maintaining the apical foramen and not changing the original canal curvature. Aim: To compare canal transportation, canal centring ability and remaining dentin thickness, in curved root canals using Twisted Files, PathFiles-ProTaper System, RaCe files, WaveOne reciprocating files and hand NiTi K-files with Cone Beam Computed Tomography. Materials and methods: 125 canals with completely formed apices and angle of curvatures ranging from 10 degrees to 60 degrees were used. The teeth were divided in five experimental groups of 25 each. Instrumentation was performed in Group I with Twisted files, Group II with PathFile-ProTaper, Group III with Hand NiTi files, Group IV with RaCe files and Group V with WaveOne reciprocating files. CBCT images were obtained before and after instrumentation with Kodak CS9300 equipment Neerja Sharma, Shafia Sarfi, Avdesh Sharma, Mandeep S Grewal. Evaluation of canal preparation with rotary and hand Niti files in curved root canals using Cone Beam Computed Tomography: An In Vitro Study. IAIM, 2017; 4(7): 45-55. Page 46 (CS3D Imaging Software 3.1.9). The amount of canal transportation, centering ability and remaining dentin thickness was calculated at nine levels. Results were analysed using ANOVA test and Post-hoc Bonferroni Multiple Comparison test. Results: Statistically significant difference was noted among the groups at the middle and apical third level with WaveOne files showing the least and hand NiTi files showing the highest transportation. The mean centering ratio was statistically highest with WaveOne and smallest with hand NiTi files at the middle third level. At the apical level (p < 0.05) the mean remaining dentin thickness was highest with WaveOne and smallest with PathFile-ProTaper. Conclusion: WaveOne and Twisted files were similar in terms of canal transportation, centring ability and remaining dentin thickness. Hand NiTi files and Pathfile-ProTaper systems produced maximum amount of canal aberrations.
ABSTRACT
Background: It won’t be wrong to admit that composite resins are currently the back bone of aesthetic and conservative dentistry. However a major drawback of composite resins is that their setting reaction involves formation of polymer chains leading to polymerization shrinkage. Aim: To compare microleakage in silorane composite using oblique, vertical and horizontal layering techniques to microleakage of nanofilled composite using oblique, vertical and horizontal layering techniques. Materials and methods: 120 extracted maxillary premolar teeth were assigned to 2 groups based on the material used Group A nanocomposite and Group B-silorane and each group was divided further into 3 subgroups depending on incremental technique used for restoration into horizontal, oblique and vertical (sub groups A1, A2, A3, B1, B2 and B3). A Class 1 cavity measuring 3mm3mm2mm was prepared in all the teeth. In group A teeth Clearfil TMSE Bond (Kurary Medical inc. Okayama, Japan) was applied. Group A teeth were filled with FiltekTM Z350 XT (nanocomposite) (3M ESPE, St Paul, USA) using horizontal (A1), oblique (A2) and vertical (A3) incremental layering technique and each Shafia Sarfi, Neerja Sharma, Ekta Garg, Dildeep Bali. Comparing microleakage in Silorane based composite and nanofilled composite using different layering techniques in class I restorations: An in vitro study. IAIM, 2017; 4(7): 23-32. Page 24 increment was cured for 30 seconds. In Group B teeth P90 system adhesive was applied and teeth were filled with FiltekTM P90 silorane (3M ESPE, St. Paul, USA) using horizontal (B1), oblique (B2) and vertical (B3) incremental layering technique. Specimens were thermocycled for 1000 cycles (5/55ºC, 30 seconds) and immersed in 2% methylene blue dye for 24 hours. Following immersion teeth were sectioned and observed under a stereomicroscope. Results were analysed using KruskalWallis test followed by Mann Whitney U test. Results: Siloranes showed significantaly less microleakage than nanofilled composites. The difference between the horizontal group, oblique group and the vertical group was found to be statistically non-significant (P value >0.05) but mean microleakage was more in vertical group compared to oblique and horizontal group. Conclusion: Within the limitations of this study, we found that Siloranes exhibit significantly less microleakage as compared to nanofilled composites irrespective of the layering technique used.