Please activate JavaScript!
Please install Adobe Flash Player, click here for download
ePaper created 2017-09-12, 09:26:18 | version 1.38.0
| case report treating complex root canal anatomy Fig. 2: Preoperative view of the maxillary second left molar temporarily restored with IRM. Note the food impaction between the first and second molar teeth. Fig. 3: Preoperative periapical radiograph showing a temporary restoration with poor marginal seal at the gingival margin. Fig. 2 Fig. 3 The CBCT scan revealed the presence of three root ca- nal systems when viewed in the axial plane; and in the sagittal plane, evidence of severe root curvatures were present in the mesiobuccal and distobuccal root canal systems. It was decided to do a more in-depth investigation as a result of this complex anatomy, using the 3D Endo Software (Dentsply Sirona). 3D Endo Software The data of the limited field of view CBCT scan was exported as a DICOM file and imported into the 3D Endo Software. The 3-D planning of the case was then completed in five easy steps. In the first step, ‘Diagnosis and Pathology’, the imported scan was reviewed in the axial, sagittal and coronal planes. The software has the ability to present a 3-D reconstructed view where the transparency of the teeth can be changed (Figs. 4a–d). The second step, ‘3D Tooth Anatomy’, involved se- lecting the tooth to be examined and the entire volume was cropped to only leave the data of interest behind (Fig. 5). In the third step, ‘Canal System’, the number of root canals were identified and each root canal was then mapped separately by identifying the orifice and radiographic apical foramen of each root canal (Fig. 6). With the fourth step, ‘3D Canal Anatomy’, the soft- ware made a proposal of the canal anatomy (Fig. 7), but the operator can make corrections according to the canal configuration that can be viewed in differ- ent planes in the software. Figures 8 to 10 show the mapping of the palatal, mesiobuccal, and distobuccal root canal systems. During the fifth step, ‘Treatment Plan’, the software projected ISO size 06 instruments into the canals (Fig. 11), which allowed the operator to visualise the internal anatomy of the canals, check straight line access, and modify the proposed access if necessary. A rubber stop on the files can then be digitally adjusted to a coronal reference point of choice that will then indicate the proposed working length for each root ca- nal system. This view can also be rotated in 3-D to alert the operator of the angle and direction of curvatures in the root canal systems (Fig. 12). The step after ‘treat- ment plan’ is to select a master file from a preloaded database of endodontic file systems that will most likely result in optimal canal preparation for that spe- cific shape or diameter of a canal. Considering the s-shaped curvatures in all three root canal systems as well as the sharp curvatures in different planes, it was decided to use the Primary WaveOne Gold file (25/07) in the palatal canal and the Small WaveOne Gold file (20/07) for root canal preparation in the two-chal- lenging buccal root canal systems (Fig. 13). The se- lected instruments were then displayed in the root canal systems and the operator again digitally rotated and visualised the root canal anatomy in 3-D (Fig. 14). Figs. 4a–d: The imported scan can be reviewed in the axial (a), sagittal (b), and coronal (c) planes and the software presents a 3-D reconstruction view (d) where the transparency of the teeth can be changed. Fig. 4a Fig. 4b Fig. 4c Fig. 4d 24 roots 3 2017