Factors associated with spontaneous re-eruption of traumatically intruded permanent anterior teeth in children and adolescents

This study aimed to examine the factors influencing the spontaneous re-eruption of permanent anterior teeth in children and adolescents after an intrusive injury. Researchers analyzed clinical data from patients aged 5 to 17 who were treated for intrusive luxation at the Peking University School and Hospital of Stomatology between June 2015 and August 2024. Key factors recorded included age, gender, degree and direction of intrusion, tooth development, associated injuries, and the eruption of adjacent teeth. Patients were categorized based on whether spontaneous re-eruption occurred during the recommended observation period, and statistical analysis was conducted using logistic regression.

A total of 170 teeth from 139 patients, aged between 5.3 and 16.3 years, with an average age of 9 years, were analyzed. Among them, 84 were male and 55 were female. Of the 170 teeth, 112 successfully underwent spontaneous re-eruption, while 58 did not. Regarding the degree of intrusion, 26.47% of teeth were intruded less than 3 mm, 60% had intrusions between 3-7 mm, and 13.53% had intrusions greater than 7 mm. In terms of direction, 68.82% of teeth experienced straight intrusion, while 10% had mesial-distal intrusion and 13.53% had buccal-lingual intrusion.

The statistical analysis revealed that mesial-distal intrusion, intrusion greater than 7 mm, and luxation of adjacent teeth were independent risk factors that reduced the likelihood of spontaneous re-eruption. On the other hand, intrusion less than 3 mm and post-osteoclastic eruption of adjacent teeth were protective factors that increased the chances of re-eruption. Additionally, as root development progressed, the probability of spontaneous re-eruption decreased by 61.1%. However, factors such as age and gingival laceration did not significantly impact the re-eruption process.

In conclusion, this study found that the severity and direction of intrusion, along with adjacent tooth injuries, play a significant role in determining whether a tooth will re-erupt on its own. While deep intrusion and adjacent tooth luxation reduce the chances of spontaneous re-eruption, minor intrusion and post-osteoclastic eruption of nearby teeth increase the likelihood of successful re-eruption during the observation period. MM-102