Severe Crowding Associated with Lower Canine Premature Resorption: Interceptive Treatment with Clear Aligners-A Pilot Study

Background: Early mixed dentition represents a critical phase since crowding conditions can occur. The interceptive resolution of dental crowding allows favorable arch and occlusal development. The aim of the present investigation was to evaluate dentoalveolar changes of clear aligner treatment planned to manage lower incisor crowding, loss of arch length, and midline deviation in early mixed dentition. Methods: A total of 13 patients (7 females, 6 males, 9.4 +/- 1.2 age) treated with clear aligners were selected. Arch dimensions and incisor inclinations were evaluated before (T0) and at the end of interceptive treatment (T1). A paired t-test was chosen to compare T1-T0 changes. The level of significance was set at 5%. Results: The greatest significant increase in mandibular width was observed at the level of the first deciduous molars (+2.44 +/- 1.4 mm), followed by the second permanent molars (+2.16 +/- 1.4 mm). Lower arch length and arch depth showed a statistically relevant increase (2 +/- 0.6 mm and 4.5 +/- 1.6 mm, respectively). The mean lower dental midline changes were statistically significant (1.42 +/- 0.73 mm). Conclusions: Early treatment with clear aligners, including the combination of transversal arch development, maintenance of leeway space, and guidance of eruption, represents a valid treatment strategy in early mixed dentition to manage arch crowding and occlusion development.