[Clinical effects of modified Nance arch appliance in the treatment of ectopic eruption of maxillary first permanent molar].
OBJECTIVE
To evaluate the effect of modified Nance arch appliance in the treatment of ectopic eruption of maxillary first permanent molar.


METHODS
Thirty children with unilateral ectopic eruption of maxillary first permanent molar were treated with modified Nance arch appliance. The mesial angle of the maxillary first permanent molars and the magnitude of the primary second molar distal root lesion before and after treatment were measured on the panoramic radiographs and analyzed statistically.


RESULTS
All 30 children completed the treatment. The mesial angle of the ectopic side significantly changed from (75.2 ± 7.6) ° before the treatment to (92.9 ± 5.2) ° after the treatment (t = -11.082, P < 0.05). The root lesion of the ectopic side significantly enlarged after the treatment, but there was no significant change on the normal side.


CONCLUSIONS
The treatment of ectopic eruption of the maxillary first permanent molar using modified Nance arch appliance was successful. The attention should be paid to the magnitude of the primary second molar distal root lesion before and after treatment and it is suggested to start the treatment when mild root resorption appears.
Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology, Beijing 100081, China.
Yu
Y
Wang
Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology, Beijing 100081, China.
He
H
Liu
Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology, Beijing 100081, China. Email: gelh0919@126.com.
Lihong
L
Ge
D002648:Child; D006801:Humans; D008437:Maxilla; D008963:Molar; D009967:Orthodontic Appliances; D011862:Radiography, Panoramic; D012391:Root Resorption; D014079:Tooth Eruption, Ectopic; D014092:Tooth Root