RESUMO
OBJECTIVE:To analysis post-treatmental reaction and long-term effect of one-visit root canal therapy by microwave instrument. METHODS:Applying heat effect and the other ones of microwave,the changes of dentine tissue of extracted teeth were observated by SEM examination.48hs and 1 year post-treatmental effect of 47 patients of periapical periodontitis treated by one-visit root canal therapy were observated and compared with the results of 54 cases treated with common method.RESULTS:In the cases of acute and chronic periapical periodontitis microwave applied in root canal therapy can close the openings of dentine,enhance the effects of sterilization and decrease times of treatment.CONCLUSION:Microwave applied in one-visit root canal therapy is competent.