FARKLI GİRİŞ KAVİTESİ TASARIMLARININ PREPARASYON ETKİNLİĞİ VE TRANSPORTASYON OLUŞUMU ÜZERİNE ETKİSİNİN BİLGİSAYARLI MİKROTOMOGRAFİ (MİKRO-BT) İLE DEĞERLENDİRİLMESİ

Abstract

The objective of this study is to assess the differences in volume and surface area after instrumentation of teeth using traditional (GGK), conservative (KGK), and ultraconservative (Ninja) (NGK) access cavities. Additionally, the study aims to investigate the formation of transport at a distance of 3 mm from the apical foramen. For the study, thirty human mandibular molars were used, specifically their mesial root canals. Periapical radiographs were used to determine root curvature. Only teeth with 25-40° curvatures were studied. The selected teeth were randomly divided into 3 groups: GGK, KGK, and NGK (n=10). Teeth were scanned with a micro-computed tomography (Micro-CT) device before access cavity preparation and root canal instrumentation. The Access cavities of all teeth were prepared under the Dental Operating Microscope using a water-cooled high-speed aerator with diamond round burs. After the access cavity preparations of all samples, the working length was determined in the mesiobuccal (MB) and mesiolingual (ML) canals. The mesial root canals of all teeth were shaped using SX, S1, S2, F1, F2 files, respectively, up to the F2 file. Between each file, the canals were irrigated using 2 mL of 2.5% NaOCl. Final irrigation was performed with 2 mL of 17% EDTA and distilled water. The Endo Activator device was used to activate the irrigation. After instrumentation, the samples were scanned again with the Micro-CT device. NRecon and CTAn software were used for visualization and quantification of volume change and non-instrumented area data. The amount of transportation in all root canals at a distance of 3 mm from the apical foramen was calculated in 2 dimensions using DataViewer software. Analysis of variance was used for repeated measurements to compare volume changes, and one-way analysis of variance was used to compare transportation formation data. The data for the non-instrumented surface area was calculated using the Kruskal-Wallis test, a non-parametric test. Tukey and Bonferroni tests were used for post hoc analysis to determine between which two groups the differences detected were. According to the results of this study, no statistically significant difference was found between the groups in volume changes after root canal preparation in MB and ML canals (p>0.05). The percentage of non-instrumented area in samples opened with NGK was statistically higher in both root canals compared to other groups (p<0.05). There was no statistically significant difference between the three cavity types in the MB root canal for the transportation values calculated in sections 3 mm away from the apical foramen (p>0.05). For the ML root canal, more canal transport was observed in the NGK groups.