Influence of Dental Plaque on Periodontitis in 18 Years

Methods: In 1985 a random sample of 3273 individuals, aged 30-40 years, were studied. Of them 1676 individuals (51.2 %), underwent a clinical oral examination. After 18 years 50 persons without chronic periodontitis were called for a clinical re-examination. They consisted of 16 persons without periodontitis in 1985 but with chronic periodontitis in 2003 (H-D group), and 31 periodontally healthy both in 1985 and 2003 (H-H group). At clinical examinations in 1985 and 2003, plaque index (PLI), gingival index (GI), calculus index (CI), pocket depth (PD), bleeding on probing (BOP) and attachment level (AL) was recorded. At the end of the study gingival crevicular fluid samples were taken by the flush method and inflammatory mediators prostaglandin E2 and granulocyte elastase were determined with radioimmunioassay and microplate assay, respectively. Students t-test, Fisherxs exact test and analysis of variance were used for statistics.

Results: In 1985 the mean PLI in H-H group were 0.68 (±0.43SD) and in H-D group 0.80 (± 0.45SD) (N.S.). In 2003 PLI in H-H group had improved significantly to 0.18 (±0.16SD), (p<0.001), and in H-D group to 0.46 (±0.36SD), (p<0.05). In 2003 there were significantly differences between the groups in PLI (p<0.001), in GI 0.16 (±0.21SD) and 1.67 (±0.98SD) (p<0.001), BOP 15.06 (±12.8SD) and 40.41 (±16.50SD) (p<0.001), PD 1.92 (±0.30SD) and 2.89 (±0.50SD) (p<0.001), AL 2.08 (±0.42SD) and 3.34 (±0.66SD) (p<0.001). In GCF the levels of prostaglandin E2 and granulocyte elastase were in the H-H and H-D groups for prostaglandin E2 0.55 (±0.54SD) and 1.64 (±65SD) pg/site and granulocyte elastase 0.019 (±0.008SD) and 0.30 (±0.16SD) mAbs/site (p<0.002 and <0.01 respectively).

Conclusion: Improvement of oral hygiene seemed to decrease to the risk for development of periodontitis in this 18-year longitudinal study.