Investigation On Apical Closure And Clinical Efficacy Of Different Obturation Techniques

Objective:To investigate the coronal micro-leakage of post-obturation by continuous wave condensation technique, heat gutta-percha vertical condensation technique, the study used traditional cold lateral condensation technique as control group by extracted teeth trial and short clinical follow-up visit. The study could supply some reference evidence for clinical choices by evaluation of obturation result and post-obturation pain.Methods:48 mandibular pre-molars which were extracted for sake of paradontosis were choosed in trial. The teeth were transected on enamelo-cemental junction and used Pro-Taper for root canal preparation by one doctor. The teeth were prepared to F3 by Crown-down technique. The teeth were grouped and obturated by different techniques: A group (control group): cold lateral obturation combined with AH-plus; B group: continuous wave condensation technique of VDW BeeFill pack; C group: continuous wave condensation technique of VDW BeeFill pack combined with AH-plus; D group: heat gutta-percha vertical condensation technique of VDW BeeFill pack combined with master apical gutta-percha and AH-plus.Experiment Section One: One third of the experimental apical was immersed in India ink staining for 7 days, and then decalcified with 6% nitric acid solution. The sample was dehydrated with gradient elution using ethanol, and placed in methyl salicylate solution to make transparent specimens which were preserved. Stereo microscope was used to observe and measure the distance of apical dye penetration in transparent specimens, and the experimental data was processed with statistical analysis. Two randomly selected samples in each group were characterized with scanning electron microscopy, to observe adaptation between root canal filling materials and wall of canals. Experiment Section Two: Through clinical observation, to compare cold lateral condensation technique with warm gutta-percha vertical condensation technique, on root canal filling efficacy, operating time and the postoperative pain response.Results:Experiment Section one: There is statistical difference in A group and B group, C group, D group of the apical micro-leakage between the values (p <0.05), B group and C group, D group of the apical micro-leakage have no significant difference between the values (p> 0.05). The images obtained via TEM show that adaptation between root canal filling materials and wall of canals is highest for D group. Experiment Section two: Observed clinical effects, A group has a significant difference in operating time (p <0.05) compared with D group, while in the postoperative pain response and filling quality, has no significant difference (p> 0.05).Conclusion:1. Heat gutta-percha vertical condensation technique is better than cold lateral condensation technique, and the former one do achieve effective ability in root canal filling. However, the best result was obtained with heat gutta-percha vertical condensation technique of VDW BeeFill pack combined with master apical gutta-percha and AH-plus2. The heat gutta-percha vertical condensation technique costs less time than cold lateral condensation technique. Through formal clinical, sterile operation, cold lateral condensation technique is also able to achieve good filling effect.