This second class shows the application of the radiographic technique in endodontics, with special emphasis on Clark's technique.
The periapical technique is the technique of choice as an aid in diagnosis, planning and proservation, and the only technique used during endodontic treatment in the maneuvers of odontometry, cone and filling tests, and in the final treatment evaluation. Through it, we can observe in a single radiograph, the crown, the root and the periapical bone, as well as all the changes that affect these structures.
Bisector and Parallelism Techniques
The radiographic technique in endodontics can vary from bisector to parallelism. The bisector technique is the most widely used in dentistry. It is so named because the x-ray beam is incident perpendicular to the bisector between the long axis of the tooth and the long axis of the film or sensor that is held in position on the palate or the alveolar lingual ridge by the patient's finger in its original technique. For positioning the film or sensor, positioners can also be used. radiographs where the x-ray beam is positioned perpendicular to the film or sensor, which in turn is parallel to the long axis of the tooth. This is possible with the use of positioners that keep the film or sensor parallel to the tooth and uniform the position of the beam by means of a guide ring. The parallelism technique has some advantages over the bisector technique, such as simplicity of execution without the need to position the patient's head, greater fidelity in the image of the shape and length of the roots, better determination of the dimensions of periapical radiolucent images, standardization of the exam for later comparisons in proservation, less overlapping of anatomical structures over the root apex and less exposure of the patient to secondary radiation. Furthermore, with the use of positioners it is easier to change the horizontal angulation, a resource widely used in endodontics.
Periapical techniques in patients with absolute isolation.
Obtaining periapical radiographs to aid in endodontic treatment is complicated by the presence of absolute isolation, which in no way prevents the technique from being performed, as long as certain principles are observed and adaptations are made if necessary. The first aspect to be observed concerns the taking of the exams without removing the set of clamp, arch and sheet. The removal of the arch and sheet is also not recommended, since, besides the possibility of contamination of the pulp chamber, it also hinders the observation of the tooth and clamp. For the execution of the technique, therefore, it is enough to pull back the sheet in three or four points of the arch on the side and arches opposite the treated tooth. A needle holder or hemostatic forceps can be used for positioning the radiographic film, when using the conventional technique. This technique allows a firm grasp of the film, simpler positioning, and usually a better acceptance of patients with nausea, as they are responsible for holding the positioner and removing it if necessary. There are also positioners on the market that allow you to take radiographs with absolute isolation in the parallelism technique. The bite block is located anterior to the radiographic film or sensor positioner and its respective localization ring. These devices allow for greater standardization of the exams, also helping in techniques that alter the angulation of the x-ray beam in relation to the orthoradial view.
Clark's technique.
The radiographic technique in endodontics, with greater use is the technique of Clark is in diagnosis (root resorptions and perforations), planning (anatomy and number of root canals), observation of files in odontometry, adjustment of gutta-percha cones, final evaluation of the treatment and proservation, through the realization of mesioradial and distroradial takes, in order to dissociate the roots and canals that are in the same plane in buccal-lingual direction, or the observation of the anatomy in flattened roots, in the same direction. The greatest use, therefore, is in the following roots: maxillary premolars, mesial vestibular root of the maxillary molars, mandibular anterior and mesial root of the mandibular molars. Another important use is to dissociate the image of the apical region from other images that may be superimposed, such as foreign bodies or anatomical structures (mandibular canal, mental foramen, incisive canal, maxillary sinus).
Fistula screening technique.
The presence of a fistula, common in cases of asymptomatic periapical abscess, may cause doubts as to the causal tooth. Not rarely in cases of its presence there are more than one tooth diagnosed with pulp necrosis and presence of periapical rarefaction, but it is important to correctly diagnose its origin.
