Age, gender and degree of inclusion are predictors of timing for spontaneous repositioning of intruded primary teeth in pre-school children

Aim: To investigate the timing for spontaneous repositioning of primary teeth with intrusive luxation in relation to degree of inclusion, gender and age of injured children. Methods: This retrospective study analysed records of 1- to 6-year-old children referred to the Section of Paediatric Dentistry, C.I.R. Dental School, University of Turin (Italy) between January 2009 and December 2020 for traumatic intrusion of primary teeth. Time to the total re-eruption was calculated, and related factors were explored using Cox and Kaplan-Meier analyses. Conclusion: Timing for spontaneous re-eruption seems to be associated to age, particularly as far as total intrusion of primary teeth is concerned. This observation could be related to the degree of bone mineralisation, which is modified during growth.