Abstract
Three orthodontic cases of spaced arch with the labial inclination of upper and/or lower incisors were reported. All cases were female and the age started orthodontic treatment was 15, 18 and 19 years old.
Swelling of papillae and gingivitis during orthodontic therapy was observed especially at the stage of space closure. It seems that gingivitis during orthodontic therapy is related to the subclinical inflammatory status of gingiva (capillary microcopically gingiva of spaced arch was frequently found to be inflammatory, however it looks normal) before orthodontic treatmant, the food retention due to the appliance and the disturbance of blood circulation due to the compression of gingiva by tooth itself at the space closure, rather than the irritation of the appliance itself.
All the gingivitis disappeared in several months after active treatment of orthodontic therapy.
