| Abstract [eng] |
In China, India, France and all the Eastern Europe countries, resorcinol-formaldehyde paste has been used for root canal treatment for many years. In Lithuania this method was widely applied almost until 1994. Consequently, dentists are still struggling to resolve endodontic retreatment problems related to the use of this material in clinical practice. The present study gives an in-depth analysis of the overall impact of the combination of both machine-driven and ultrasound instruments on root dentin. In addition, the reliability of diagnostic methods (i.e. dyeing with methylene blue and inspection under microscope), which are commonly used in dental clinical practice in order to detect dentin cracks in teeth previously treated with RF paste when their colour differs from the neutral colour of the tooth tissue, have been tested in the study. Moreover, a study of resistance to fracture was carried out not only to evaluate the impact of load on root dentin after the endodontic retreatment but also to assess the level of the impact that dentin surface defects resulting from the retreatment can have on the tooth strength. The results of the present study in vitro are difficult to be interpreted and directly related to the real clinical situation. Still, the results allow to make certain assumptions when it comes to the prognosis of endodontic retreatment of such teeth. |
