Tooth loss and alveolar remodeling in 'Sinosaurus triassicus' (Dinosauria: Theropoda) from the Lower Jurassic strata of the Lufeng Basin, China

Abstract

Pathological or traumatic loss of teeth often results in the resorption and remodeling of the affected alveoli in mammals. However, instances of alveolar remodeling in reptiles are rare. A remodeled alveolus in the maxilla of the Chinese theropod 'Sinosaurus' (Lower Jurassic Lower Lufeng Formation) is the first confirmed example of such dental pathology in a dinosaur. Given the known relationship between feeding behavior and tooth damage in theropods (teeth with spalled enamel, tooth crowns embedded in bone) and the absence of dentary, maxillary, and premaxillary osteomyelitis, traumatic loss of a tooth is most likely the cause of alveolar remodeling. Based on the extent of remodeling, the injury and subsequent tooth loss were non-fatal in this individual.