Relapse after orthodontic correction of maxillary median diastema: A follow-up evaluation of consecutive cases

An evaluation of 96 treated orthodontic patients with maxillary median dias tema ranging from 0.50 mm to 5.62 mm (mean 1.22, SD 0.85) was performed 4.0 to 9.0 years after completion of active treatment. Pre- and posttreatment data were gathered from available records. Follow-up data were gathered fro m records and interviews of 37 patients, and from phone interviews of 59 pa tients. The incidence of diastema relapse was 49% when scored as either pre sence of a measurable space at follow-up, a history of orthodontic or prost hetic retreatment to close a reopened space, or continued use of a retainer to control relapse tendency. Logistic regression analysis revealed that pr etreatment diastema size and presence of a family member with a similar con dition were the only significant risk factors for relapse (p<0.05), while p retreatment spacing in the maxillary anterior dentition approached signific ance (p=0.10). No association was found between relapse and presence of an abnormal frenum or an osseous intermaxillary cleft, although patients with an abnormal frenum had a wider pretreatment diastema than those with a norm al frenum (p<0.05). Fremitus of the maxillary incisors was the only paramet er at follow-up associated with space reopening (p<0.01).