Impact of orthodontic treatment on front teeth with prior history of dental injury: a 4-year follow up.

OBJECTIVES

The primary aim of this study is to describe the pulpal outcome of front teeth (definitive upper and lower incisors and canines) with prior injury at start (T1), completion (T2) and follow-up (T3) of orthodontic treatment, analyzing the impact of trauma type, orthodontic appliance and oral habits on the prevalence and severity of root resorption (RR), compared with surrounding front teeth without trauma. Additionally, the influence of upper central incisor extraction on treatment duration, esthetic outcomes and patient satisfaction was investigated.

METHODS

Pulpal outcomes at T1, T2 and T3 were compared using Fisher's Exact test. The odds ratio for prevalence and severity of RR of front teeth after orthodontic treatment and its relationship with oral habits were calculated using cumulative logistic regression. The impact of incisor extraction on treatment duration, patient satisfaction and esthetic outcomes was analyzed using Pairwise comparisons.

RESULTS

141 patients were included (79 male, mean age at T1 13.7 ± 5.9 years, mean follow-up 4.7 ± 2.2 years). 51.5% of the injuries involved periodontal damage, 33% involved incisor extraction. Injured front teeth were significantly more prone to pulp necrosis and presented 4 times more RR after orthodontic treatment compared to their non-injured counterparts, independently of the orthodontic appliance used. The longer the orthodontic treatment, the higher the risk for RR. Nail biting and lip interposition led to higher risk of RR, but not tongue thrust. Gingival line and papillary integrity were worse in incisor extraction, although patient satisfaction remained high (> 70%).

CONCLUSION AND CLINICAL RELEVANCE: Injured front teeth are more prone to pulpal complications and RR than those without trauma. Long courses of treatment should be avoided, especially in severe injuries. Incisor extraction led to significantly worse gingival esthetic outcomes, although this didn't influence patient satisfaction.