Inflammatory Effect of Self-ligating Brackets in Patients With Aggressive Periodontitis

Objectives: Patients with aggressive periodontitis (AP) show signs of complex malocclusions and a diminished periodontium, which is why they require orthodontic treatment with biomechanical variations during the alignment phase. A new generation of self-ligating brackets (SLB) could improve the periodontal support, however, the evidence about the effect of this technology in patients with AP is limited. The aim of this study was compare the effect of SLB and conventional brackets (CB) on the periodontal status and crevicular fluid (CF) cytokine profiles during the dental alignment phase.
Methods: Twelve patients with inactive AP were evaluated. Patients were matched for periodontal condition based on the number of teeth and clinical attachment level (CAL) at baseline, to receive either orthodontic therapy. Periodontal indices were taken by a calibrated periodontist. Clinical measurements and crevicular fluid (CF) samples were taken at the beginning of treatment (T0), at 3 (T1) and 6 months (T2). Concentrations of cytokines were determined by Cytometric-Bead-Array.
Results: CB patients showed an increase in gingival index at T1 and T2 (p=0.06 and p=0.05 respectively). Similar results were observed for bleeding on probing among T0 to T1 (p=0.04) and T1 to T2 (p=0.039). However, SLB patients were not showed this increment. There was gain for CAL through the time in both groups (p<0.05). No differences were observed for pro-inflammatory cytokines nor the Th1 profile (p>0.05). The Th17 profile cytokines were increased among T0 and T1 and stabilized in T3. IL17F and IL23 showed significant changes especially in T1 (p<0.05), which correlated significantly with plaque levels at T1 r=0.58.
Conclusions: Although there were no significant differences in periodontal status, GI and hemorrhage were significantly lower in SLB. The increased expression of Th17 cytokines might suggest that this profile could be closely related to bone resorption induced in the orthodontic alignment phase which may overexpressed by the plaque buildup.