| Objectives To compare the apical sealability and root filling quality and root fracture resistance of the second generation of normal temperature flowing gutta-percha,GuttaFlow2,when using the Ni-Ti root canal file to prepare for the three tapers of 02,04and 06.AH-Plus sealer filling was used as a control study.It provides a theoretical basis for improving the apical sealability and root fracture resistance of GuttaFlow2 in the clinic and provides theoretical support for promoting the promotion of the normal temperature flowing gutta-percha.To explore the theoretical study of selecting the appropriate root canal preparation scheme combined with suitable root canal filling materials to achieve the best apical sealability and root fracture resistance.Methods Experiment 1 Experiment of GuttaFlow2 filling and AH-Plus filling apical sealability and filling quality of three kinds of taper root canal preparation.1 Micro-leakage experiment:36 mandibular premolars with single root and straight root canal were removed within one month,randomly divided into group A(02 taper),group B(04 taper),group C(06 taper).There are three groups,n=12.With the Ni-Ti instrument of NIC~?Super File prepared to group A:0.02 taper,30~#;Group B:0.04 taper,30~#;Group C:0.06 taper,30~#.The experimental group was filled with GuttaFlow2,and the control group was filled with AH-Plus sealer.Combined with the methylene blue staining method and the transparent tooth method,the vernier caliper measures the size of the apical micro-leakage value under the stereo microscope.2 Proportion of filling gutta-percha:The experiment selected 30 mandibular premolars with single root and straight root canal extracted within one month,randomly divided into a(02 taper),b(04 taper),c(06 taper)There are three groups,n=10.Use the NIC~?Super File to prepare to group a:0.02 taper,30~#;group b:0.04taper,30~#;group c:0.06 taper,30~#.The root canal was filled with GuttaFlow2,and the tooth was cut perpendicular to the long axis of the tooth at a distance of 3 mm and 6 mm from the apex.The filling of the tooth in each cross section was observed under a stereo microscope and images were collected.The percentage of the area of the gutta-percha and the area of the root canal was calculated using Photoshop 9.0,which is PGFA(percentage of gutta-percha-filled area).Experiment 2 Experiment of GuttaFlow2 filling and AH-Plus filling root fracture resistance after three kinds of taper root canal preparation.36mandibular premolars with single root and straight root canal were removed within one month.Root canal preparation and root canal filling were performed according to the micro-leakage test.The standard test piece was vertically pressed on a universal material testing machine at a speed of 1 mm/min until the root fractured,and the pressure value at the moment of breaking was recorded,which is the maximum bending force(in N)of the root,record data and statistical analysis.Results Experiment 1 1 The results of root apex micro-leakage values of three kinds of taper root canals after filling with two root filling systems suggest:The average micro-leakage of the 02,04,and 06 taper groups in the GuttaFlow2 filling group showed a downward trend,but there was no significant difference between the 02 taper group and the 04 taper group(P>0.05).There was a statistical difference between the 04 and 06 taper groups(P<0.05).There was also a statistical difference between the 02 and 06 taper groups(P<0.05).There was no significant difference in the mean value of micro-leakage between the 02,04,and 06 taper groups in the AH-Plus filling group(P>0.05).Compared with the two root filling systems under the same taper,the microleakage values of the GuttaFlow2group were smaller than those of the AH-Plus group at 02 taper,04 taper and 06 taper,but there was a statistical difference between the 06 taper(P<0.05).2 After filling the three taper root canals with GuttaFlow2,with the taper of the root canal increased,the PGFA of the 06 taper group was significantly higher than the 02 taper group at 3 mm from the root apex.The PGFA between the three groups was statistically significant difference(P<0.05).At 6 mm from the root apex,PGFA increased,but there was no statistical difference(P>0.05).With the increase of taper,the number of under-filled root canal in the three groups decreased,but there was no statistical difference between the three groups(P>0.05).Experiment 2 Results of the root resistance of three kinds of taper root canals using two root filling systems.The root fracture resistance of the 02 taper,04 taper and 06 taper root canal was gradually reduced after filling with GuttaFlow2 and AH-Plus.There was no significant difference in the GuttaFlow2 group between the three tapers(P>0.05),and there was significant difference in the AH-Plus group(P<0.05).At 06 taper,the root fracture resistance of GuttaFlow2 group and AH-Plus group was statistically different(P<0.05).Conclusions 1 Three kinds of taper root canal preparations have different degrees of apical micro-leakage for GuttaFlow2 filling system and AH-Plus sealer filling.The sealing effect of GuttaFlow2 filling system is better than AH-Plus sealer filling.2 Three taper root canal preparations have an effect on the GuttaFlow2 filling system,and the apical sealing performance is best after 06 taper root canal preparation,which has no effect on AH-Plus sealer filling.3 Three kinds of taper root canal preparations have an effect on the densification degree of the GuttaFlow2 filling system at a distance of 3 mm from the root apex,and the root canal gutta-percha filling after 06 taper root canal preparation is the most compact.4 For the three tapers of 02,04 and 06,with the increase of the taper,whether the GuttaFlow2 filling system or the AH-Plus sealer filling will reduce the root fracture resistance.5 In the three tapers,when the root canal was prepared to be 06 taper,the root fracture resistance of the GuttaFlow2 filling system was greater than that of the AH-Plus paste,and there was a statistical difference.Figure 12,Table 13,Reference 110. |
PDF Full Text Request