[Studies comparing the efficacy of root canal filling with gutta-percha lateral condensation and Thermafil obturators].
A comparative analysis of the efficacy of root canal filling with laterally condensed gutta-percha and Thermafil obturators with titanium carrier was performed on the basis of experimental and clinical findings. Experimental part. Twenty-four extracted human teeth with root canals filled with laterally condensed gutta-percha (12 teeth) or Thermafil obturators (12 teeth) were studied in order to evaluate the quality of root filling. The Apexit sealer was used in both groups. Radiographs were obtained and the linear dye penetration test was done. Placement, homogeneity and adaptation of root canal filling were evaluated on the radiographs. Twenty teeth with root canals filled with laterally condensed gutta-percha (10 teeth) or Thermafil obturators (10 teeth) were studied using SEM. Clinical part. Eighty-seven patients were enrolled. One hundred and sixty-two single canal teeth with irreversible pulp disease with vitale (70 cases) or necrotic (54 cases) pulp and chronic apical parodontitis (38 cases) comprised the study material. Group I consisted of 84 teeth with root canals filled with laterally condensed gutta-percha, while group II had 78 teeth with Thermafil obturators. The Apexit sealer was applied in both groups. In vitro radiological examination revealed a better quality of placement of root canal fillings in group I (11 correctly filled root canals, 1 underfilling) when compared to group II (1 correctly filled root canal, 11 overfillings). No differences were observed between groups as to homogeneity or adaptation of root canal filling. The seal evaluated using the linear dye penetration test revealed no differences between both types of root canal filling. SEM confirmed the presence of interfaces between the filling material and root canal wall in both groups. The width of interface in group I was 1-5 microns, seldom exceeding 10 microns, and uniform throughout the whole root canal. In group II the width varied from 1-5 microns in the apical part to 10-25 microns in the middle and coronal parts. SEM revealed no major differences regarding homogeneity between both groups. Radiographs performed in the clinical part showed a higher frequency of overfillings of root canal filling into the apical parodontium in group I (30.8%) than II (9.5%). Thermafil turned out to be less satisfactory with regard to adaptation of root canal filling to the canal walls. Evaluation of immediate results of treatment demonstrated no differences between both techniques. A positive result after one year was found in 94.2% of laterally condensed gutta-percha fillings and in 90.2% of Thermafil fillings. After two years, the respective figures were 93.7% and 90.0%. The use of Thermafil obturators seems to be less tedious and time-consuming when compared to laterally condensed gutta-percha.