Entfernung endodontischer Thermafil-Obturatoren mit Hilfe unterschiedlicher Techniken: Eine Micro-Computertomographie-Studie
Removal of Thermafil obturators using different techniques. A micro-computed tomography study
von Max Klinger
Datum der mündl. Prüfung:2020-11-16
Erschienen:2020-11-02
Betreuer:Prof. Dr. Michael Hülsmann
Gutachter:Prof. Dr. Michael Hülsmann
Gutachter:Prof. Dr. Matthias Rödiger
Dateien
Name:[27.10.2020] Max Klinger Dissertation.pdf
Size:1.22Mb
Format:PDF
Zusammenfassung
Englisch
Aim: The aim of this study was to compare two techniques for removal of Thermafil obturators from curved root canals in mandibular molars. Methodology: Sixty mesial root canals in extracted mandibular molars were distributed into matched pairs according to degree and radius of curvature. All root canals were prepared to size 35, 04 taper and obturated with Thermafil obturators size 35, which then all were shortened to a length of 9 mm. The teeth were embedded in resin, mounted in a mannequin head and isolated with rubber dam to simulate clinical conditions. Removal of Thermafil obturators was undertaken under a dental microscope by an experienced endodontist. In one tooth of each pair removal of the Thermafil carrier was attempted using the FragRemover loop device, in the other tooth Reciproc NiTi instruments were used. Pre- and postoperative micro-CT-scans were taken to compare the amount of remaining filling material and the amount of dentine removed during removal of the Thermafil obturator. Eventual problems during removal attempts were recorded. Results: Reciproc removed 24 Thermafil carriers (80%), 16 in one piece, 8 in small pieces, 6 cases failed. The FragRemover removed 12 carriers (40%), 18 cases failed, the difference was statistically significant (P = 0.003). Reciproc left less remaining filling material than the FragRemover (P = 0.002), but removed more dentine in the apical part of the root canal (P < 0.01). There was no significant difference concerning the total amount of removed dentine (P = 0.38) between both groups. Conclusions: Reciproc was more effective in removal of Thermafil carriers, whereas the FragRemover removed less dentine and left more obturation material. A protocol for a combination of both devices would be beneficial.
Keywords: FragRemover; Reciproc; Retreatment; Thermafil