Objective: Pathologic migration is defined as a change in tooth position, resulting from a disruption of forces that maintain the teeth in the normal position with reference to the skull. Clinical evidence is limited that pathologically migrated teeth may reposition themselves after periodontal therapy. The current study was carried out to determine the frequency of spontaneous repositioning of pathologically migrated teeth after periodontal therapy, and to study the relation between the severity of migration and the degree of repositioning following treatment. Method and Materials: Twenty-five patients aged 20 to 45 years with moderate to severe form of periodontitis presenting 52 diastema sites secondary to pathologic migration involving maxillary anterior teeth participated in the study. After conventional periodontal treatment had been performed, reactive repositioning was assessed by measuring the space between pathologically migrated teeth and adjacent teeth on study models and radiographs obtained at baseline, reevaluation at 4 weeks after scaling and root planing (SRP), 3 months after periodontal surgery, and 6 months from baseline. Results: No changes were noted after SRP. On study models, 88.46% of all sites (46 of 52 sites) demonstrated various degrees of repositioning (both partial closure and complete closure) after periodontal therapy 6 months after baseline. Of these 46 sites, all exhibited improvement after surgical therapy. Labiopalatal repositioning was seen in 32 out of 51 teeth (62.74%). On radiographs, 77.27% of all sites (34 of 44 sites) demonstrated various degrees of repositioning (both partial closure and complete closure) after periodontal therapy 6 months after baseline. Of these 34 sites, all exhibited improvement after surgical therapy. Complete repositioning occurred in 34.61% and partial closure was seen in 53.80%. Conclusion: The findings suggest that spontaneous repositioning after periodontal therapy is likely, particularly when light to moderate degrees of pathologic migration are considered. Schlagwörter: pathologic tooth migration, periodontal therapy, spontaneous repositioning, tooth movement, wound healing