Background: Orthodontic space closure following premolar extraction may result in gingival cleft formation. This may contribute to orthodontic relapse due to reopening of extraction spaces. Aim: 1) To evaluate the effects gingival clefts have on relapse and opening of closed extraction spaces after orthodontic treatment. 2) To record any changes in cleft severity. 3) To establish any relationship between gingival phenotype and cleft severity. Methods: Subjects recruited from previous study in which the occurrence and severity of gingival clefts were measured during space closure. The clinical measures included the occurrence and severity of clefts and their relationship to gingival phenotype. Results: Sites with a cleft (N=42) had 42.86% relapse and those without (N=19) had 36.84% relapse. Conclusions: As cleft severity increases; the amount of relapse distance is likely to increase. Adult patients are at greater risk for relapse at extraction sites compared to adolescent patients.