The risk of healing complications in primary teeth with root fractures: A retrospective cohort study

Primary teeth are frequently affected by traumatic dental injuries. Root fractures are rare and have a reported incidence of 2% in the primary dentition. Hence, there is limited evidence on this topic. This study aims to evaluate the risk of healing complications in primary teeth with root fracture and to identify possible sequelae in the permanent dentition following root fracture in the primary dentition.

A retrospective analysis of a cohort of 53 patients with 74 root fractured primary teeth. The standard follow-up program included clinical and radiographic examination after 4 weeks, 8 weeks, 6 months, and 1 year after the trauma and when the patient was 6 years of age. The following complications were registered: pulp necrosis (PN), pulp canal obliteration (PCO), ankylosis with replacement root resorption (ARR), infection-related root resorption (IRR), premature tooth loss (PTL), and repair-related resorption (RRR).

The Kaplan-Meier and Aalen-Johansen estimators were employed. The level of significance was 5%.

A total of 74 teeth were included. 42 teeth were extracted at the initial examination. Risks estimated after 3 years: PTL 45.9% [95% CI: 28.8-63.0], PCO 12.9% [95% CI: 2.3-23.4], PN 14.9% [95% CI: 3.9-25.9], RRR 2.6% [95% CI: 0.0-7.5]. No teeth showed ARR or IRR. All complications were diagnosed within the first year. Most common sequelae in the permanent dentition was demarcated opacities, with an estimated risk of 20% [95% CI: 8.2-41.3].

There is a low risk of healing complications following a root fracture in the primary dentition. Root fractures often result in early extraction of the coronal fragment. The remaining apical fragment will undergo a physiological resorption. Aside from opacities, there is a low risk of sequelae in the permanent dentition.