Discussion
A dilacerated tooth has been described as one tooth in which the root is curved 90° or more to the long axis of the tooth, or one tooth in which the apical portion of the root is more than 20° from the axis (8, 9). A study of 3150 teeth from 800 patients in Iran found a 1.65% prevalence of tooth dilacerations: 7.5% in males and 5% in females. Mandibular third molars exhibited the highest occurrence of dilacerations at 14%. (2). A dilaceration in root canal significantly increases the risk of procedural accidents, including loss of apical patency, canal transportation, perforation, ledge formation, and instrument fracture, which could compromise infection control and the treatment outcome (10). To enhance the effectiveness of root canal treatments and minimize complications, a comprehensive understanding of the complex anatomy of tooth canals is essential (11). Detailed information on root canal curvature and complexity of dilacerated tooth aids in the proper planning of treatment, and selection of appropriate materials and techniques (12, 13). Studies have stated the importance of 3D imaging modalities such as CBCT for the proper visualization of canal morphology, which is of paramount importance to avoid mishaps like perforation or transportation during instrumentation (13). The implication of this thorough understanding is not only in the enhancement of procedural efficiency but also in guaranteeing the long-term success of endodontic treatments (13). Also, modern NiTi rotary instruments and dynamic irrigation improve speed, safety, and outcomes in complex root cases (6, 7). The single-cone, warm vertical compaction, and lateral condensation techniques are common methods for obturation in curved canals, each varying in effectiveness (8). A strong seal using appropriate filling materials is key to preventing infections and enhancing longevity post-procedure (9, 10, 11).
In dilacerated teeth, prior to starting root canal treatment, the radiograph should be used to determine the degree of canal curvature. The junction of a straight line from the orifice through the coronal portion of the root and another straight line from the apex through the apical portion of the canal forms the interior angle (12, 13). The Schneider approach categorizes the canals into three groups: I) straight (0–5°), II) moderate (5–20°), and III) severe (>20°); thus, moderate and severe were classified as curved canals (14, 15). But, in measuring double-curved root curvature, the method of Southard et al. is more effective as it utilizes three lines in differentiating curve angles compared to Schneider’s method, which was concerned with only a single curvature angle by measuring the deviation between the coronal and apical path of the canal (16, 17). This technique quantifies curvatures by calculating two angles: the first is between the long axis of the file’s coronal shaft and a ”best fit” line representing the canal’s initial curvature, while the second is between this line and the apical segment (16).