Bone Defects Formation with Orthodontic Intrusion in Periodontal Patients

Aims: The purpose of this study was to investigate whether it was feasible to change the horizontal bone defect into an angular bone defect to prepare for periodontal regenerative therapy after orthodontic intrusion. Methods: Orthodontic intrusion of elongated maxillary incisors was performed in 11 adult periodontally compromised patients, combined with CSF and root planing. The long-cone parallel periapical films and CBCT were taken before the start of treatment (T0) and after the finishing of orthodontic intrusion and alignment (T1). The data were analyzed statistically by using one sample t-test and paired t-test. Results: From T0 to T1, the distance from CEJ to the crestal alveolar bone in the labial, lingual, mesial and distal side had mean decreases of 0.69 mm (P > 0.05), 0.64 mm (P > 0.05), 0.74 mm (P < 0.05), and 0.53 mm (P < 0.05), respectively. Angular bone defects displayed in the labial side of two teeth, in the mesial side of three teeth, in the distal side of six teeth and two teeth (underwent single tooth intrusion) were indicated for GTR therapy. Conclusions: 1. The distance from CEJ to the crestal alveolar bone has significant decrease in the mesial and distal side of all test teeth. 2. It's easier to form angular osseous defects in a single elongated tooth by orthodontic intrusion with fiberotomy and root planing. 3. It's difficult to form angular bone defects in thin facial or lingual alveolar plates.