The treatment of the large periradicular endodontic injury.

Periradicular lesions of endodontic origin are characterized by polymicrobial infections, part of which appear to play a crucial role in the facultative anaerobic bacterical species. In literature there is a strong disagreement about the choice of treatment in large periradicular lesions of endodontic origin: some authors propose the orthograde root canal therapy, others surgical therapy with apicectomia, retrograde filling of the cavity and review instrument. The purpose of this study was to demonstrate the effectiveness of orthograde endodontic treatment in case of periapical lesions of endodontic origin of dimensions larger than 20 mm. It was evaluated a sample of 60 cases, ages between 18 and 70 years, 32 men and 28 women. The cases have been treated by orthograde endodontic. Were included mono and pluriradicular teeth with periapical lesion of endodontic origin primary or secondary at endodontic incongruous treatment, with dimensions larger than 20 mm. The sample was divided into Group A: 19 cases in which was possible to complete the root canal therapy in the same event; Group B: 41 cases in which there was drainage. Dressing was applied with pure calcium hydroxide, which was renewed every 10 days for a maximum of 30, was eventually completed the endodontic therapy. Group A: 13 out of 19 cases showed healing at 5 years. Of the remaining 6, there were three failures, a crown-root fracture, missed two follow-up. At 10 years of the 13 successes, 2 cases showed relapse. Group B: 41 cases, later reduced to 30 we had 19 successes in 5 years. Of the remaining 11: 3 crown-root fractures, 2 missed the follow-up, 6 failures. At 10 years of the 19 successes, two were lost because of fracture, one for a relapse. Discussion. The results show the importance of drainage, which can affect the apical seal and therefore the success of endodontic therapy, but allows decompression of the periradicular lesion and symptoms regression. The use of calcium hydroxide in the intermediary dressings allows the neutralization of acidic compounds, alkaline phosphatase activation creating a significant development of the antibacterial action. Proper instrumentation and cleansing of root canals allows the reduction of over one thousand times the bacterial load. The coronal seal has, through the adhesive techniques of restorative materials, a crucial role in closing the doors of entry the bacterial contamination of treated root canals. The endodontic therapy by orthograde is considered primary therapeutic choice in case of large endodontic lesions, given the success at rate both 5 (Group A 68,41%, Group B 63,33%) and 10 years (Group A 57.88%, Group B 53.32%)