O impacto da terapia não cirúrgica na expressão de marcadores de apoptose em biópsias gengivais de pacientes com doença periodontal

Abstract

The aim of this study was to evaluate the impact of non-surgical periodontal therapy on the expression of apoptosis markers Bad, Bcl-xL, Bim, Mcl-1 and the Bax/Bcl-2 dimer, in gingival biopsies from patients with generalized periodontitis stage III and IV after 1 year of follow-up. As a secondary aim, we aim to evaluate the impact of the treatment on the gingival tissue of patients with gingivitis. Nineteen subjects with gingivitis (41.1  5.6) and 15 patients with generalized periodontitis stage III and IV (55.9  9.6 years) were included in the study. All teeth were evaluated, except third molars, for Pocket Depth (PD), Clinical Attachment Level (CAL), Visible Plaque Index (VPI) and Bleeding on Probing (BOP). In the teeth where the biopsies were collected, the Plaque Index (PI) and Gingival Index (GI) were also evaluated. One biopsy was collected from each patient in both groups at baseline and another after 1 year. Gingival tissue was collected with a 1.5 mm diameter punch above the bottom of the periodontal pocket or sulcus and immediately stored at -70° Celsius (C). Subsequently, the samples were weighed, macerated in a cell disruptor and analyzed in a multiplex-type microsphere immunoassay. The expression of apoptotic markers wer shown in nanogram per milligram of tissue (ng/mg). Periodontitis patients received 4 sessions of nonsurgical periodontal therapy and gingivitis patients were treated in a single session. In addition to baseline, periodontitis group received treatment after 3 months, 6 months and 1 year. And gingivitis group, after 1 year. The values of %IPV, %SS, %PB 4 - 6, %PB > 7, %NIC > 5, and also PB, NIC, IP and IG, relative to the biopsy sites, significantly reduced in the periodontitis group at 3, 6 months and 1 year when compared to baseline. There was a significant reduction in the same parameters in the multiple analysis. And the values of %PB < 3 and %NIC < 2 significantly increased at 1 year. In the gingivitis group, the values of %IPV, %SS, IP (biopsy site) and IG (biopsy site) were significantly reduced after 1 year. At baseline, Mcl-1 concentrations in the gingival tissue of periodontitis patients were significantly lower when compared with gingivitis patients (p = 0,002). Bim concentrations significantly increased in the gingival tissue of gingivitis patients after 1 year (p = 0.04). Periodontitis patients shows significantly reduction of the difference of Bim concentrations between baseline and 1 year (delta), when compared to gingivitis patients (p = 0.036). We concluded that non-surgical periodontal therapy did not led to a significant difference in the expression of apoptosis markers Bad, Bcl-xL, Bim, Mcl-1 and the Bax/Bcl-2 dimer in gingival biopsies from patients with generalized periodontitis stage III and IV after 1 year of treatment. However it caused a significant increase in the expression of the proapoptotic marker Bim in gingival tissue of gingivitis patients.