Postretention stability after orthodontic closure of maxillary interincisor diastemas

Abstract

Anterior spaces may interfere with smile attractiveness and compromise dentofacial harmony. They are among the most frequent reasons why patients seek orthodontic treatment. However, midline diastema is commonly cited as a malocclusion with high relapse incidence by orthodontists.ObjectivesThis study aimed to evaluate the stability of maxillary interincisor diastemas closure and the association of their relapse and interincisor width, overjet, overbite and root parallelism.Material and MethodsSample comprised 30 patients with at least a pretreatment midline diastema of 0.5 mm or greater after eruption of the maxillary permanent canines. Dental casts and panoramic radiographs were taken at pretreatment, posttreatment and postretention.ResultsBefore treatment, midline diastema width was 1.52 mm (SD=0.88) and right and left lateral diastema widths were 0.55 mm (SD=0.56) and 0.57 mm (SD=0.53), respectively. According to repeated measures analysis of variance, only midline diastema demonstrated significant relapse. In the overall sample the average relapse of midline diastema was 0.49 mm (SD=0.66), whilst the unstable patients showed a mean space reopening of 0.78 mm (SD=0.66). Diastema closure in the area between central and lateral incisors showed great stability. Multivariate correlation tests showed that only initial diastema width (β=0.60) and relapse of overjet (β=0.39) presented association with relapse of midline diastema.ConclusionsMidline diastema relapse was statistically significant and occurred in 60% of the sample, while lateral diastemas closure remained stable after treatment. Only initial diastema width and overjet relapse showed association with relapse of midline diastema. There was no association between relapse of interincisor diastema and root parallelism.

Closing a Large Maxillary Median Diastema using Bapat Power Arm

“… 4 15 However, some mesial inclination of central incisors is preferred. 14 One follow-up study reported relapse of median diastema in 49% patients and found wider initial width of diastema and fremitus of maxillary incisors strongly associated with space opening. 16 Though the prevalence of mesiodens is reported to be only 0.15 to 2.2% of the population with a preference to males, 17 their presence in the maxillary arch could be deleterious from the esthetic and functional points of view.…”

“…Another study found midline diastema recurrence in 60% of the sample with stronger correlation of relapse with larger initial diastema width, relapse of overjet, and intermaxillary osseous cleft and concluded that midline diastema closure is highly unstable, hence, needs lifetime wear of maxillary fixed retainer. 14 Inadequate root parallelism at the end of treatment has been also cited as a reason for median diastema relapse. 4 15 However, some mesial inclination of central incisors is preferred.…”

Stability of Diastemas Closure after Orthodontic Treatment

“…While midline diastema relapse occurred in 60% of the sample, lateral diastemas closure remained stable after treatment. Only initial diastema width and overjet relapse showed association with relapse of midline diastema [46].…”

An odontometric study of tooth dimension in diastematic dentition

“…Depending on the aetiology, the treatment may also take place in a different way, i.e. orthodontic treatment [13,17,24] or surgical treatment [32,34] of diastema.…”