Interceptive treatment of palatal impaction of maxillary canines with rapid maxillary expansion: A randomized clinical trial

Abstract

Introduction: Our aim in this prospective randomized clinical study was to assess the prevalence rate of eruption of palatally displaced canines, diagnosed at an early developmental stage with posteroanterior radiographs and consequently treated by rapid maxillary expansion. Methods: A sample of 60 subjects in the early mixed dentition with palatally displaced canines diagnosed on posteroanterior radiographs was enrolled in the trial. Their age range at the first observation (T1) was 7.6 to 9.6 years, with a prepubertal stage of skeletal maturity (CS1 or CS2). The 60 subjects were randomly allocated to the treatment group (TG, 35 subjects) or the no-treatment group (NTG, 25 subjects). The TG was treated with a banded rapid maxillary expander; after expansion, all patients were retained with the expander in place for 6 months. Thereafter, the expander was removed, and the patients wore a retention plate at night for a year. The NTG received no treatment. All subjects were reevaluated in the early permanent dentition (T2) (postpubertal CS4). The number of dropouts was recorded. The main outcome recorded at T2 was successful or unsuccessful eruption of the maxillary permanent canines. The starting forms at T1 for measurements on posteroanterior and panoramic films were compared in the 2 groups with the Mann-Whitney U test (P \0.05). The prevalence rates of successful and unsuccessful treatments in the TG were compared with those in NTG with chi-square tests (P \0.05). From T1 to T2, there were 3 dropouts in each group. Results: The final sample comprised 32 subjects in the TG and 22 subjects in the NTG. No statistically significant differences were found for any variable at T1. The prevalence rates of successful eruption of the maxillary canines were 65.7% (21 subjects) in the TG and 13.6% (3 subjects) in the NTG. The comparison was statistically significant (chi-square 5 12.4; P \0.001). Subjects with palatally displaced canines in the early mixed dentition do not have transverse deficiency of the maxillary arch. Conclusions: The use of a rapid maxillary expander as an early interceptive approach is effective for increasing the rate of eruption of palatally displaced canines. (Am J Orthod Dentofacial Orthop 2009;136:657-61)

Dalla malposizione all'inclusione del canino mascellare: diagnosi e previsione di eruzione

“…Nonostante l'esteso interesse sia per l'eziologia sia per la terapia dei canini dislocati, solo pochi studi negli ultimi vent'anni hanno focalizzato la loro attenzione sulle misure di terapia preventiva dell'inclusione canina [7,8,18,29,[32][33][34][35][36][37].…”

Diversas modalidades de intervención temprana de caninos ectópicos.

“…1 Después del tercer molar, el canino superior es el diente que más se ve afectado por este fenómeno 3, 4 con una frecuencia de un 0.2% -2.8% en la población. 5,6 La impactación palatina es mucho más frecuente (85%) que la vestibular (15%) 3,6 y ocurre dos veces más en mujeres que en hombres. 7 En cuanto a su etiología hay dos teorías principales para explicar el desarrollo de la impactación canina maxilar: la teoría de la "guía" y la teoría "genética".…”

“…5 Los sujetos que presentaban uno o ambos caninos desplazados a palatino se dividieron en dos grupos: un grupo sin tratamiento (NTG) y un grupo con tratamiento (TG). Se analizó mediante radiografías laterales, radiografías panorámicas y radiografías posteroanterior en una etapa inicial (T1) y luego de 4 años (T2).…”

“…Posterior a ello se removió el expansor y usaron por las noches una placa de retención por 1 año. 5 Los resultados indican que sujetos tratados con el expansor tienen una tasa de éxito eruptivo de un 65,7%, casi 5 veces mayor que los pacientes sin tratamiento (13,6%). Esta prevalencia es similar a la lograda con sólo la extracción de caninos temporales según reportado en la literatura, pero inferior, si se compara con el uso del arco de tracción cervical más la extracción de caninos temporales (87,5%) o la extracción de caninos combinada con el uso de un expansor (80%).…”

“…Esta prevalencia es similar a la lograda con sólo la extracción de caninos temporales según reportado en la literatura, pero inferior, si se compara con el uso del arco de tracción cervical más la extracción de caninos temporales (87,5%) o la extracción de caninos combinada con el uso de un expansor (80%). 5 Lo distinto del estudio es el diagnóstico y tratamiento temprano de caninos desplazados a palatino.…”