Levels of platelet activating factor in gingival crevice fluid following periodontal surgical therapy.

BACKGROUND AND OBJECTIVE: Elevated levels of platelet activating factor (PAF), a potent inflammatory phospholipid mediator, have been previously detected in gingival tissues and gingival crevice fluid (GCF) in periodontal disease. However, the role of this mediator during wound healing after periodontal surgery remains unclear. The hypothesis, a relationship between PAF levels and periodontal healing, was tested by measuring PAF levels in GCF samples collected from sites that had undergone guided tissue regeneration (GTR) or flap surgery. MATERIAL AND METHODS: Using a split-mouth design, 30 intrabony defects were randomly assigned to treatment with GTR (group 1) or to flap surgery (group 2). GCF was sampled pre-operatively and at 6-, 12- and 24-wk follow-up evaluation visits. PAF levels in GCF were analyzed by high-performance liquid chromatography (HPLC). RESULTS: Both treatment modalities significantly reduced the probing pocket depth and improved the clinical attachment level (p < 0.01). Compared with pre-operative values, the GCF volume and PAF levels were significantly decreased at postoperative weeks 6, 12 and 24 in both groups (p < 0.01). There were also significant differences in GCF volume and PAF levels at all time points up to 24 wks in both groups (p < 0.01). No statistically significant differences were observed in any of the parameters investigated between the two groups (p > 0.05). CONCLUSION: PAF is detectable in GCF by HPLC and showed a continuous decrease at all the time points monitored following periodontal surgical therapy. This suggests that changes in the levels of this mediator in GCF might be useful for monitoring the progress of periodontal repair and regeneration.

In vitro effects of alcohol-containing and alcohol-free mouthrinses on microhardness of some restorative materials.

Daily application of mouthrinses has been recommended for the prevention and control of caries and periodontal disease. The aim of this study was to evaluate the effect of alcohol-containing and alcohol-free mouthrinses on the microhardness of three restorative materials. Materials tested included visible light cured (VLC) composite resin (Amelogen), VLC glass-ionomer cement (Fuji II LC) and a fissure sealant (Ultra Seal XT). Eighteen cylinders of each restorative were fabricated and initially stored in distilled water for 24 h. Six samples of the restoratives were stored for 12 hours to simulate a 2 min/day for 1 year exposure to mouthrinses in the following solutions: distilled water (control), alcohol-containing mouthrinse (Viadent) and alcohol-free mouthrinse (Rembrandt). At the end of the test period microhardness was measured with a Tukon microhardness tester. Kruskal-Wallis one-way analysis of variance was used to analyse the data. Both mouthrinses affected the hardness of the materials tested.

Marginal seal of a resin-modified glass-ionomer restorative material: an investigation of placement techniques.

This study examined marginal seal of a visible resin-modified glass-ionomer restorative material. Class V cavity preparations in extracted human premolars were restored with one of four different placement techniques: bulk placement, vertical incremental placement, incremental placement with the gingival increment placed first, or incremental placement with the occlusal increment placed first. Either a cervical former or a hand instrument was used to contour the restorations. Measurement of dye penetration indicated that there was no statistically significant differences in microleakage among the groups, by placement technique or method of contouring. However, two groups contoured with a cervical former were found to be 100% leakage free.