Activity of platelet activating factor acetylhydrolase following phase I periodontal therapy

Elevated levels of platelet activating factor (PAF), a potent inflammatory mediator in periodontal disease and decreased PAF levels following periodontal surgical therapy have been previously detected in gingival tissues and gingival crevicular fluid (GCF). Platelet activating factor acetylhydrolase (PAF-AH) is a calcium-independent phospholipase A2 that catalyses the hydrolysis of PAF, thereby inactivating this mediator The hypothesis, a relationship between activity of PAF-AH and healing following periodontal therapy, was tested by detecting activity of PAF-AH in GCF samples collected from sites that had undergone phase I periodontal therapy with generalized chronic periodontitis. Twenty patients with generalized chronic periodontitis were divided into two groups (n = 10): group 1 with probing pocket depth (PPD) 4-5 mm and group 2 with PPD > or = 6-8 mm. Clinical parameters were recorded and GCF was sampled before phase I periodontal therapy and at the 2nd, 7th, 14th, 21st and 28th day follow-up evaluation visits. Activity of PAF-AH in GCF was analysed by enzyme-linked immunosorbent assay (ELISA). Probing pocket depth at the 21st and 28th day in group 1, and PPD at the 14th, 21st and 28th day in group 2 were significantly decreased when compared to the baseline values (p < 0.001). Activity of PAF-AH (micromol/ml) was significantly decreased at the 7th, 14th, 21st and 28th day following phase I periodontal therapy in both groups 1 and 2 compared to the baseline values (p < 0.05). Platelet activating factor acetylhydrolase is detectable in GCF by ELISA and showed a continuous decrease following phase I periodontal therapy. Changes in the PAF-AH activity would be a progressive marker of periodontal healing to evaluate the success of periodontal therapies.