Risk factors associated with the occurrence of avulsion in the primary incisors: A case-control study.

BACKGROUND: Identifying factors associated with the occurrence of primary tooth avulsion is essential to promote prevention strategies. AIM: To investigate the risk factors associated with primary incisor avulsion and variables associated with post-avulsion sequelae in the permanent successor. DESIGN: This case-control study comprised 407 children (cases) with primary incisor avulsion and 407 children (controls) with other traumatic dental injuries (TDI). The association between explanatory variables and avulsion was evaluated through logistic regression. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated. Poisson regression analyses between potential explanatory variables and sequelae were run, from which relative risks (RR) and corresponding 95% CI were estimated. RESULTS: TDI caused by moderate falls (OR = 2.20; 95% CI = 1.47 to 3.27), affecting lateral incisors (OR = 10.10; 95% CI = 3.89 to 26.54) and the lower arch (OR = 9.54; 95% CI = 3.15 to 28.85), were associated with primary incisor avulsion. Moreover, children with previous severe TDI, anterior open bite, and anterior crossbite had higher odds of primary incisor avulsion. Children who suffered from any primary tooth avulsion (RR = 2.68; 95% CI = 1.82 to 3.95) had a higher risk of sequelae in the permanent successors. The risk for sequelae in the permanent teeth was significantly greater for younger children under age 2 years than for children ages 3 to 5 years. CONCLUSION: Risk factors for primary incisor avulsion are related to the severity of the fall, tooth position, history of previous TDI, and malocclusion. Furthermore, avulsion increases the risk of sequelae in the permanent successors.

Impact of avulsion of the primary incisors on the occurrence of sequelae in the permanent teeth: A retrospective cohort study.

OBJECTIVES: The purpose of this retrospective cohort study was to investigate the occurrence of sequelae in the permanent teeth after avulsion of their primary antecessors and to evaluate the factors associated with this occurrence. METHODS: We screened 2922 records of patients with photographic and radiographic images who attended a reference centre for dental trauma in the primary teeth from 1998 to 2019. Among them, 240 were eligible records of children who had suffered avulsion of the primary incisors and were followed up until complete eruption of the permanent successors. Multilevel Poisson regression analyses were conducted between the explanatory variables related to children and avulsed teeth; outcome variables were occurrences of any type of sequelae in the permanent teeth, opacities, hypoplasia and malformation. Relative risks (RRs) and respective 95% confidence intervals (95% CIs) were calculated. RESULTS: Among the 240 children's records, 194 fulfilled the inclusion criteria. Finally, we found 266 primary avulsed teeth and 115 (43.2%) permanent teeth presenting with sequelae. Avulsion occurring when children were older than 4 years (RR = 0.48; 95% CI = 0.24-0.95) had lower risks for developing sequelae than children aged 0-2 years of age. Additionally, when avulsion occurred in the lower dental arch (RR = 1.45; 95% CI = 1.06-1.99) and when three or more teeth were affected (RR = 1.57; 95% CI = 1.02-2.41), the occurrence of sequelae in the permanent teeth was more probable than if avulsion occurred in the upper arch and affected only a single tooth. Age older than 3 years was a protective factor for the occurrence of hypoplasia and age older than 4 years protective for the occurrence of opacities. CONCLUSIONS: The risk of sequelae in the permanent teeth after avulsion of their antecessor is higher when the trauma occurs in young children (<2 years) and in patients with avulsions of greater magnitude, such as when it affects the lower jaw, and more teeth are involved.