Comparison of Abundance of Premolar and Molar Pulp Stones Before and After Orthodontic Treatment Using Panoramic Radiography

Pulp stone is a focal calcification in dental pulp, which is often detected on conventional dental radiographs. Pulp stones can complicate easy access to the root canal and pulp chamber in root canal treatment. Orthodontic treatment may be associated with the formation of pulp stones. Therefore, this study examined the number of pulp stones pre- and post-orthodontic treatment. In this retrospective cross-sectional comparative study, 222 digital panoramic radiographs collected from private orthodontic offices in Rasht, were divided into two groups: radiographs of patients undergoing orthodontic and non-orthodontic treatment according to the inclusion criteria. The obtained data were analyzed by SPSS via the Wilcoxon and Mann-Whitney tests (P<0.05). The difference in the number of pulp stones pre- and post-orthodontic treatment was significant (P<0.0001). The maximum number of pulp stones after orthodontic treatment was observed in second molars (P=0.016). The change in the number of pulp stones in the mandible (P=0.001) was significantly higher than that in the maxilla (P=0.002). This change was also greater in the left side (P<0.0001) than in the right side (P=0.002). The changes in the number of pulp stones was significant in females (P=0.02). Age had an insignificant effect on pulp stone formation (P>0.05). This study showed the effect of orthodontic treatment on the number of pulp stones. Further studies are required to clarify the underlying mechanisms for this increase and come up with strategies to prevent it.