Use of Mineral Trioxide Aggregate in the Treatment of Traumatized Permanent Teeth With Necrotic Pulps and Chronic Periapical Lesions

Root canal procedures will be performed on single-rooted traumatized permanent teeth (both with mature and immature root development) with necrotic pulps and periaoical lesions. Following access opening in each tooth, the root canals will be gently debrided with a crown-down manual technique using K-files according to the radiographically determined working lengths; irrigation with saline was used in all cases. K-files will be only used to remove the necrotic tissue and the softened predentinal layer without excessive removal of mineralized dentin, as this may have further weaken already thin walls of the root canals, particularly those with immature apical development. Subsequently, a reshaping of the canal system, followed by a minor curettage of the periapical area through the canal using barbed broaches will be made in order to partially destruct the periapical lesion and provoke bleeding. Final irrigation will be performed using 2% NaOCl (Chloraxid, Cerkamed, Stalowa Wola-Poland), 0.2% solution of chlorhexidine-digluconate (Curasept 220, Curadent Swiss GmbH, Kriens-Switzerland) and 40% citric acid solution (40% Citric acid, Cerkamed, Stalowa Wola, Poland). The canals will be then dried with sterile paper points and filled with triple-antibiotics paste using a lentula, for a period of seven days. Following this initial disinfection, calcium-hydroxide paste will be placed into the root canals for at least four weeks, for a maximum of six weeks (UltraCal XS, Ultradent Products Inc., South Jordan, UT USA). Apical thirds of the root canals will be obturated either with ProRoot MTA (Dentsply Tulsa Dental Specialties, Tulsa, OK USA) or MTA+ Cerkamed (Cerkamed, Stalowa Wola, Poland) by forming an apical plug of 3-5 mm of thickness. The correct placement of the apical plug will be assessed radiographically, and the moist cotton pellet was left in the root canal. The next day, the rest of the canal space will be filled with a sealer (Acroseal, Septodont, Saint-Maur des Frosses-France) and gutta-percha points (Guttapercha, VDW GmbH, Munich-Germany) using a lateral compaction technique. Coronal parts of root canal systems will be sealed using glass-ionomer cement (Fuji IX, GC Int., Tokyo, Japan) with a minimum thickness of 1.5-2 mm. The teeth will be restored using composite material (Gradia Direct, GC Int., Tokyo, Japan). Two dentists with many years of clinical experience, and using identical, predetermined treatment protocols will perform all treatments.

The positive clinical outcome will comprise of absence of spontaneous or provoked pain, no discomfort during chewing, no numbness or tenderness to percussion and/or palpation, no altered tooth mobility, tooth crown discoloration or abscess and/or sinus tract. Radiological assessment of the outcomes will be performed according to the analysis of post treatment radiographs (initial, baseline, 3, 6, 12, and 24-months subsequent to obturation) after being photographed using a digital camera Kodak EasyShare Max (Z990) with millimetre measurer in order to obtain interpretation of sizes of periapical lesions during conversion of pixels in mm2 by digital data processing in Adobe Photoshop CS software.