Orthopantomogram is an overview X-ray of all teeth and tissues of the upper and lower jaw. It allows you to diagnose anomalies and curvatures of the dentition, the condition of periodontal tissues, leak-tightness of fillings, latent caries, the condition of the jaw bone at the site of tooth extraction. A snapshot of the dental system is made by an orthopantomograph device. There is a film orthopantomogram, representing a traditional snapshot, and a digital OPG, whose data is stored electronically.
Orthopantomogram (OPG) is included in the international dental standards of treatment and diagnosis. In therapeutic dentistry, OPG is necessary to determine the oral cavity sanitation plan; in periodontics – for the treatment of periodontal diseases; in orthodontics – for the assessment and correction of malocclusion; in orthopedics and implantology – for planning dental prosthetics and dental implantation; in surgical dentistry – for making a decision on the expediency of tooth extraction, surgical interventions (filling bone cavities with osteoplastic materials, sinus lifting) and evaluating their results.
Orthopantomogram can be prescribed for complaints of pain of indeterminate localization in the oral cavity, teeth or jaws. The study provides a complete picture of the localization and structure of wisdom teeth, which is extremely important for planning therapeutic tactics in relation to them. OPG can be performed for children from 5-6 years of age to monitor the development of dental plates, control teething, assess the degree of mineralization, determine dental age.
With the help of an orthopantomogram, the initial stage of carious lesions of the teeth is recognized, canal filling is monitored; changes in the supporting apparatus of the tooth and bone tissues, destructive and pathological processes (bone resorption, cyst, granuloma, odontoma, osteomyelitis) are recorded; the presence of dystopian and retinated teeth, oral tumors, dental or facial injuries, as well as other dental anomalies is determined. OPG may have a certain diagnostic value for an ENT doctor when evaluating the maxillary sinuses, nasal passages, and nasal septum.
The only contraindication to conducting an overview radiography of the dentition is pregnancy. The possibility of performing an orthopantomogram during fetal gestation should be agreed with an obstetrician-gynecologist and a neonatologist.
Types of orthopantomograms
The study can be performed in a film or digital version. A digital orthopantomogram is a more modern modification of the study; it allows you to get a clearer image, process it using various settings (increase the size, increase contrast, change the polarity, etc.), store and send electronically. Digital OPG is almost instantly displayed on the monitor, can be stored in the patient’s personal electronic card or issued to him on any digital medium.
With the advent of digital orthopantomographs, the film OPG has practically lost its significance, since the picture on the film looks more blurry, it soon loses the clarity of the image. Despite the fact that the price of a digital orthopantomogram is higher than a film one, the intensity of irradiation and exposure time are reduced by 2-3 times during digital examination.
Methodology of conducting
The fundamental importance for obtaining a high-quality orthopantomogram is the correct and stationary position of the patient. Before taking a picture, it is necessary to get rid of removable dentures, chains, pendants, earrings. The main reference point when removing the OPG is the precisely selected chin rest, which ensures the symmetry of the location of the head of the subject along three mutually perpendicular planes. At the time of radiography, the neck should be straightened and the shoulders lowered. The head is fixed by means of frontal and parietal fixators, the tongue is asked to be pressed to the palate. These requirements exclude shadow layers and distortions in the survey area.
An overview orthopantomogram is performed on an orthopantomograph apparatus, which consists of an X-ray emitter (tube) and a receiver (sensitive digital sensor or film). To take a picture, the emitter and receiver move in different directions around the head of the subject. The result is a two-dimensional planar image of the arch of the mouth. When removing the orthopantomogram, a special apron is put on the patient, protecting him from X-ray irradiation. Orthopantomography lasts for several seconds and does not cause any negative feelings.
Interpretation of results
On a high-quality orthopantomogram, the closed jaws seem to “smile”: at the same time, the edges of the dentition are slightly raised. With the help of OPG, an objective view of the patient’s dental apparatus is formed. The picture shows all the formed teeth, rudiments, super-complete teeth, their shape, number and location in the bone, parallelism of the roots. Based on the orthopantomogram, uncomplicated and complicated caries, hidden carious cavities and other foci of odontogenic infection are detected; the condition of fillings and channels. By studying the X-ray, an experienced specialist will determine changes in the supporting apparatus of the teeth (periodontal), bone tissues, temporomandibular joints, sinuses of the nose.