Figure 2.

Radiographic sequence of the diverse endodontic techniques performed in permanent teeth with necrotic pulp and open apices included in this study. Technique 1: MTA apical barrier: (A) Pre-operative radiograph of tooth #22. (B) Radiographic verification of 0.5mm Ca(OH)2 powder placement as a resorbable extra-radicular barrier against which a 5 mm MTA was packed. (C) Final radiograph with a visible remaining canal filled with gutta-percha and the cervical third reinforced with composite resin. Technique 2: Ca(OH)2 replacements: (D) Pre-operative radiograph of tooth #12. (E) Radiographic aspect where the main canal seemed to have become calcified, which indicated that the entire canal had been adequately filled with Ca(OH)2. (F) After 2 Ca(OH)2 replacements over 9 months, a new hard tissue barrier was radiographically detected, and the root canal was subsequently filled with gutta-percha embedded in a calcium hydroxide sealer. Technique 3: Gutta-percha filling: (G) Pre-operative sinus tract radiograph of tooth #11. (H) Radiographic examination of size #80 master gutta-percha cone. (I) Final radiograph after 2-visit root canal treatment. Technique 4: Plug with Ca(OH)2/gutta-percha filling: (J) Pre-operative radiograph of tooth #21. (K) Radiographic examination of the apical adaptation of a master gutta-percha cone individualized through a softened filling technique. (L) Once the 0.5 mm Ca(OH)2 powder was placed as an apical plug, it was radiographically verified via the gutta-percha filling.