Sequelae and prognosis of intruded primary incisors: a retrospective study

This study was designed to assess the sequelae and prognosis of intruded primary incisors.

Of 196 children who visited the emergency clinic due to intrusion of 310 maxillary primary incisors, 110 children (172 teeth) were available for follow-up examination (study group). Eighty-six children (138 teeth) did not show for the follow-up examination (non-respondents group). Male/female ratio was 1.7:1. Age range of children at time of injury was 12-72 months (mean 28). Follow-up time ranged between 0 and 59 months (mean 27).

Fifty-seven percent of all teeth were completely intruded. In 80%, the root was pushed labially. All but two ankylosed teeth re-erupted, and 37% of these re-erupted into an ectopic position. Completely intruded incisors re-erupted into an ectopic position in a higher percentage (45%) than partially intruded teeth (30%). Fifty-two percent of the teeth presented pulp canal obliteration (PCO). Sixty-four percent of the completely intruded incisors presented PCO compared to 40% of partially intruded teeth. Arrest of dentin apposition was found in 15% of the teeth, and was not affected by the degree of intrusion. Twenty-three teeth were extracted shortly after the injury due to suspect of contact with the developing permanent successor (19 teeth) and severe caries (4 teeth). Sixty-eight percent of the intruded teeth survived more than 36 months after the injury. Twenty-three percent were extracted due to periodontal breakdown and 5% due to repeated trauma. Antibiotic therapy did not have any effect on the survival rate.

The majority of intruded primary incisors may re-erupt and survive with no complications after more than 36 months post trauma even in cases of complete intrusion and fracture of the labial bone plate.