Objective: Our objective was to compare the diagnostic capabilities of the orthopantomogram (OPT) as a standard dental diagnostic procedure with those of cone-beam computed tomography (CBCT). We examined the extent to which the OPT allowed miniscrew position to be estimated, and whether probands from different backgrounds in dental medicine arrived at the same conclusions regarding the screw position using the same radiological images (OPTs).
Materials and methods: First, a tomas® pin 8 mm in length and 1.2 mm in diameter (Dentaurum, Ispringen, Germany) was inserted in all four quadrants of nine macerated skulls. These nine skulls were then imaged by OPT and CBCT. The OPTs were presented to probands whose task it was to estimate the miniscrew position in relation to the neighboring structures in an evaluation form. The probands surveyed came from three different backgrounds in dental medicine: orthodontists, oral and maxillofacial surgeons, and dental students. Comparison with the CBCT was made by measuring the CBCTs using the GALILEOS Viewer (Sirona, Bensheim, Germany), and these results were compared with those in the evaluation forms.
Results: In this study, it could be shown that none of the three proband groups estimated the screw's position in the OPT significantly better or worse in comparison to the CBCT. The probands' assessments of the miniscrew's proximity to the dental root differed, and in many cases did not correspond exactly with the CBCT measurement. The majority of probands estimated the likelihood of an opposing corticalis perforation as small, as confirmed in the CBCTs. The proximity of the miniscrew to the maxillary sinus or inferior alveolar nerve was similarly assessed by most of the probands, as also determined in the CBCT. However, the OPT assessments of some probands of the proximity to the maxillary sinus and/or inferior alveolar nerve differed from the proximity measured in the CBCT.
Conclusion: Overall our study demonstrates that the OPTs enabled a rough evaluation of the miniscrew position in relation to the surrounding structures. However, the probands' assessments were imprecise. Major deviations appeared in the determination of the proximity of the screw to the dental root. For this reason, if there is any doubt, patients should take advantage of three-dimensional (3D) diagnostics, preferably before any surgical intervention. This is true, for example, if it is unclear whether a root will be or has been perforated, or indeed whether there is sufficient transverse bone tissue.