Index
It is an extremely useful amination radiograph in all dental specifications.
Applications
- Carious lesions and endodontics.
- Prosthesis.
- Maxillofacial Surgery.
- Implantology
- Pediatric dentistry
- Orthodontics.
Abbreviation for the Orthopantomography: OPT.
Mechanism
Panoramic radiography is an important and a complex factor in diagnosis and prognosis, being often a surprise investigation of expected elements of dentomaxillary pathology.
This technique requires the use of a specialized OPT unit, the tomographic principle being the one used to produce the image of the full mouth and its dentition.
The mobile tube effectively diffuses the shadow of the overlapping structures by placing the dental arch on the axis of the tomographic movement.
The structures that are not within this axis are effectively blurred, so that their details do not overlap the image of the teeth and jaw.
However, the area of interest shows some element of lack of clarity compared to the radiographic images of other parts of the body when a non-mobile tube is used.
The technique opens the image of the dental arch so that it appears in a linear arrangement in the final image. It has been used for a long time in the dental field and has largely replaced periapical full mouth exams.
The OPT exam can be used to demonstrate the temporomandibular joints and jaw.
The tomographic movement of the unit attempts to follow the dental arch, which remains within the tomographic axis of the ray as it travels around the patient’s face.
Because of this, the precise positioning aims to place the dental arch within this axis and horizontally to follow the plane of movement of the tube.
The positioning also aims to keep clear unwanted structures, such as the cervical vertebrae, from the tomographic axis.
Some tomographic units use a system of slit light beams that are aligned with the incisors, the median sagittal plane (MSP), the anthropological baseline, or the alatragal line.
The lights are also used to assess the patient’s position in an anteroposterior (AP) direction; these vertical bundles are superimposed when the patient is in the optimal plane, but they are separated if the patient is too advanced or not too far.
As all these light arrangements are used in different ways for each manufacturer, it is difficult to describe the use of each different system.
It can often be difficult to align the baselines with the lights of the OPT unit once they are on.
Visual evaluation of the baselines before turning on the lights often helps, and the radiographer uses the lights to check the height and positioning accuracy afterwards.
The X-ray beam exits the tube housing through a slit collimator and the thin beam moves around the dental arch and through the image receptor (IR); this arrangement reduces the inevitable penumbra that would be caused by a wider beam.
However, some penumbral effects are inevitable.
The tomographic movement travels around the head with a horizontal beam, as opposed to the traditional tomographic units that move over the supine patient and use a beam that is initially vertical and moves longitudinally or in a circular, elliptical or helical course.
Clinical situations in which orthopantomographies are recommended
These situations are the following:
- First examination of new patients (patients with multiple deep carious lesions, with orthodontic and periodontal problems).
- Early diagnosis of dental anomalies (diagnosis omitted especially at the ages of 10, 15 and 20 years), to verify the dentition and provide an opportune diagnosis of tumors or cysts.
- Establish the exact cause of tooth loss.
- Radiographic examination of the teeth with endodontic treatment.
- Suspected odontogenic sinus disease.
- ATM disorders caused by malocclusion (in such cases, the orthopantomogram must be performed with the patient in habitual occlusion).
- Facial and maxillary asymmetry.
- Painful or asymptomatic swelling
- Multiple dental extractions, with sustenance osteomyelitis pectada.
- Examination of non-odontogenic cysts, tumors and bone lesions similar to tumors.
- Suspicion of tumors or invasive bone bones ( metastasis ).
- Paresthesia of the mandibular nerve.
- Unusual sensitivity of the teeth, unusual rashes.
- Separation, spacing or migration of the teeth.
- Radiographic examination of the maxillofacial area orography in systemic diseases and syndromes.
- Maxillofacial fractures and suspected post-traumatic fractures.
- Before and after surgery in Macilofacial surgery.
