This study aimed to analyse common panoramic errors among children with DD as compared with those of ND pattern. Our results showed errors in both groups, with more panoramic errors (especially movement and positioning errors) in DD population as compared to ND matching population, which was inversely correlated with age. Overall, only 25% of the evaluated panoramic radiographs were error-free, and in patients with DD only 8% were error-free.
Intraoral radiographs may be uncomfortable for pediatric patients, especially if the patients have DD, sometimes to the point it is impossible to perform the radiographs. In some cases, a panoramic image can be used instead of an intra-oral radiograph. However, panoramic imaging requires 8.2–19.0 s13, which compared with the shorter time for intraoral radiographs, increases the risk of being affected by movement or lack of correct positioning during the scan. Studies indicate that panoramic radiography is prone to various errors and image quality which fundamentally depend on correct positioning and cooperation of the patient4,5,6,14,15.
This study is novel as it focuses on errors in patients with special needs. Granlund et al. and Peretz et al. investigated errors in panoramic images of healthy pediatric patients with mixed dentition and found that the incidences of error free images were 4% and 2.7%, respectively6,14. Furthermore, both Granlund et al. and Peretz et al. found that PAS appearance was the most common error, appearing in 79% and 64% of panoramic images, respectively. In the current study we found the same frequency for PAS, movement, and positioning errors (80%)6,14. The frequencies were significantly higher in the DD group as compared to the ND group. Images of younger patients showed more movement and positioning errors. Movement during exposure was the most frequent error found among the study group (74% as compared to only 6% in the ND group). Anxiety-provoking experiences and a lack of cognitive abilities to follow instructions might explain this finding9,10,16,17.
In this study more than half of the images (56%) were considered low-quality images, 48% in the DD group as compared to only 6% in the ND group. This finding was consistent with other studies. Peretz et al.14 found 45% of the radiographs of patients with mixed dentition, and 39% of the radiographs of patients with permanent dentition, were of low quality. In addition, Choi et al.18 investigated the level of clinical image quality of panoramic radiographs among children and adults and found 41% of the images were of poor quality.
The differences in errors’ frequency and image quality between the current study and the other studies6,14,18 may be attributed to the fact that panoramic images taken in our imaging unit are performed by three experienced technicians with more than 10 years of experience. It is possible that in other imaging centers the frequencies of errors will be much higher, maybe to a point where it will be impossible to image these children at all, which will impair the possibility of providing them with appropriate treatment. Alternatively, patients with special needs may be treated with compromised images, thus their treatment may be compromised as well.
Children with special needs are a widespread population. In 2015, the Israel National Council for the Child reported that approximately 13% of Israeli children are with special needs19, and there is an increasing prevalence of developmental difficulties among Israeli children20. Imaging these children can be challenging to the patient, parent, and technician due to lack of cooperation, poor technician-patient/parent communication skills, technician knowledge gaps on the issue, and body/skeletal malformations that might be present21,22. Therefore, it is appropriate to develop protocols for radiographic examination suitable for this population. Dailey and Brooks23 provided guidelines for applying basic and advanced techniques for dental radiographic examinations for children with autism spectrum disorder. These techniques included proper preparation, visual schedule, visual incentives, social stories, and the use of sedation. There is a need for more similar studies that include various diagnoses and special needs.
One limitation of the study is that it includes a sample of radiographs available in the medical records. It is possible that there were patients in whom a panoramic radiograph was not performed due to the patient’s inability to position himself in the machine properly or without moving. The data about the non-performance of panoramic for these reasons were not documented or difficult to locate, which leads to missing information regarding the extent of the population not capable of performing panoramic radiographs due to DD. Another limitation is that DD comprises a wide spectrum of conditions with an extensive array of clinical manifestations. This makes the test group heterogeneous, making it difficult to draw specific conclusions or guidelines.
In conclusion, our study suggests that the imaging of young pediatric patients, especially those with DD, must be performed in special suitable centers with special equipment and protocols, to have diagnostic images. Knowledgeable and skilled staff is needed to position the child in an appropriate position, maintain the position during exposure, and more importantly to achieve diagnostic imaging for effective treatment planning with reduced repetitions. This would decrease the risk of radiation exposure, as pediatric patients are more radiosensitive than adults.