Purpose: The purpose of this study was to examine the effects of placement of retraction cord subgingivally upon periodontal indices including plaque index (PI), gingival index (GI), pocket depth (PD), bleeding on probing (BOP), and attachment level (AL), as well as gingival crevicular fluid (GCF) and TNF-α levels. Methods: Ten teeth in 6 patients who were periodontally healthy were selected. These teeth had pocket depths of 3 mm or less, no evidence of significant loss of attachment, BOP, or plaque accumulation. The patients each received an oral prophylaxis. The following week, baseline measurements of periodontal indices and TNF-α were taken and the retraction cord was placed for 15 minutes. Following removal, the patients were dismissed. The periodontal indices measured included PI, GI, PD, BOP, and AL. In addition, the levels of TNF-α in GCF, were investigated. These measurements were made before gingival retraction as a baseline and on the 1st, 3rd, 7th, 14th, and 28th days post retraction. Results: A repeated measures ANOVA showed that TNF-α levels in GCF were significantly increased at all five intervals after gingival retraction compared to the baseline. The mean TNF-α level peaked at Day 1 (0.90 ± 0.62), then declined at Days 3 (0.53 ± 0.16), 7 (0.43 ± 0.08), 14 (0.47 ± 0.10), and 28 (0.43 ± 0.08) but was still elevated 54% above baseline at Day 28, p < 0.01. The GI was significantly elevated at Day 1 (0.9 ± 0.49), p < 0.01; Day 3 (0.53 ± 0.32); and Day 7 (0.33 ± 0.33), p < 0.05. Unlike TNF-α, GI recovered to the baseline by day 14. Other periodontal parameters, PI, PD, BOP, and AL were not significantly altered by the gingival retraction procedure. Conclusion: This pilot study supports the previous research that gingival retraction causes an acute injury that heals clinically in 2 weeks as is indicated by the GI. It also provides the first evidence that gingival retraction results in an elevation of the proinflammatory cytokine, TNF-α, in GCF.
All Science Journal Classification (ASJC) codes
- Fixed prosthodontics
- Gingival retraction