Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for inflammation control and pain relief. However, while adjunct use of NSAIDs is avoided for periodontal therapy because of related side effects, cyclic administration of NSAIDs may reduce or eliminate these effects. The investigators evaluated the effect of a cyclic diclofenac potassium regimen on clinical parameters and levels of prostaglandin E2 (PGE2) and interleukin-1beta (IL-1beta) in the gingival crevicular fluid (GCF) of subjects with periodontitis. Forty-one subjects with moderate to chronic periodontitis (33 men, 8 women) were divided into two groups (test and control) after initial periodontal therapy. During this 6-month, randomized, double-blind, placebo-controlled study, test (n = 28) and control (n = 13) groups were administered a cyclic regimen of diclofenac potassium (50 mg, twice daily) or placebo. Clinical measurements of disease severity and GCF sample collections were made at baseline, 2, 4 and 6 months. GCF levels of PGE2 and IL1-1beta were determined using EIA and ELISA kits, respectively.

Study Design This study utilized a randomized, controlled, double-blind, parallel-group design to investigate the 6-month effect of a cyclic regimen of diclofenac potassium [50 mg, twice daily (b.i.d)] on clinical parameters of periodontal disease and levels of PGE2 and IL-1beta in GCF. After clinical and radiographic examination, subjects were divided into two groups: 28 patients in the test group and 13 patients in the control group. Of the 28 patients in the test group, ten (nine men, one woman) were smokers, eleven (six women, five men) were non-smokers, and seven (all men) were ex-smokers. Thirteen patients in the control group comprised six smokers (five men, one woman), five non-smokers (four women, one man) and two ex-smokers (both men).

Test and control groups were administered either diclofenac potassium (50 mg) or placebo gel caps (containing inactive filler of starch flour and carboxymethylcellulose), respectively, b.i.d. after a meal for 6 months in a cyclic regimen. Administration of diclofenac potassium or placebo was undertaken from baseline to 2 months, no drug (diclofenac potassium or placebo) was administered from 2 to 4 months, then diclofenac potassium or placebo therapy was reinstituted (b.i.d.) from 4 to 6 months. To promote compliance, each patient was recalled monthly. Patients in both groups were instructed on oral hygiene, including tooth brushing for at least 2 minutes (b.i.d.) and daily interdental cleaning. SRP was not carried out during these recalls. During the screening period (baseline as well as 2, 4 and 6 months), all subjects underwent physical examinations and biochemical analyses (blood chemistry, complete blood count, urinalyses and pregnancy testing).

Inclusion Criteria:

• with moderate to chronic periodontal disease
• (at least two sites with loss of clinical attachment > 4mm
• alveolar bone loss of 30-50%, as judged by radiography
• received initial periodontal therapy, including scaling and root planning, as well as oral hygiene instruction less than six weeks before study commencement.

Exclusion Criteria:

• history of cardiovascular disease, renal disease, bleeding in the upper gastrointestinal tract, gastrointestinal ulcers, asthma, hypersensitivity to diclofenac or other NSAIDs, prosthetic joint replacement, or other chronic disease affecting compliance
• received antibiotics or antibacterial agents less than 6 months before study commencement
• received NSAIDs within 1 month, or phenytoin or calcium antagonists within 3 months
• history of pregnancy, lactation, or inadequate birth control