Radiological Late Dental Adverse Effects Following Treatment for Paediatric Head and Neck Rhabdomyosarcoma: Results of a Transatlantic Multicentre Cohort Study

Objectives: Rhabdomyosarcoma represents the most common paediatric soft tissue sarcoma, with 40% occurring in the head and neck region. Given that survival rates now reach 80%, minimising late adverse effects, particularly dental developmental complications, has become a priority. The aim of this paper was to identify the scope, severity and range of such late dental effects following treatment for head and neck sarcoma. Materials and Methods: We systematically investigated late dental adverse events using orthopantomograms in rhabdomyosarcoma survivors treated between 1990 and 2014. Orthopantomograms were evaluated using a validated scoring system (DENTALE) that evaluates skeletal deformations, tooth presence, tooth wear, crown shape, eruption, root-crown ratio and root shape. Results: Among 103 survivors (median age at diagnosis 5.4 years, 42.7% female), 92.2% exhibited dental adverse effects. Missing molars occurred in 45.6% of survivors. Root abnormalities were present in 72.8% of survivors, crown-to-root ratio abnormalities in 56.3% and eruption disturbances in 45.6%. Age at diagnosis was inversely correlated with total adverse effect score (r_s = −0.389, p < 0.001). Survivors diagnosed before age 6 had significantly higher total dental adverse effect scores (p = 0.008), showing more effects of crowns (p = 0.016), crown-root ratio (p = 0.020), tooth eruption (p = 0.005) and roots (p = 0.006). Conclusion: This study demonstrates that rhabdomyosarcoma survivors are at substantial risk for a variety of dental developmental issues when treated at a younger age. Consequently, routine dental screening during follow-up is essential, with specialised dental and orthodontic care provided when clinically indicated.