Local gingival blood flow at healthy and inflamed sites measured by laser Doppler flowmetry

Background: This investigation aimed to: 1) develop a method to obtain reproducible laser Doppler flow readings (LDFRs) at the gingiva of the maxillary front teeth; 2) evaluate regional gingival blood flow (GBF) in healthy gingiva by laser Doppler flowmetry; 3) compare hand-held LDFR (H-LDFR) with splint LDFR (S-LDFR); and 4) monitor changes in GBF in experimental gingivitis (EG) and chronic gingivitis (CG). Methods: The LDFR, gingival index (GI), and plaque index (PI) were measured at 1.3 gingival sites (teeth #6 to # 11) in 10 healthy volunteers (five males and five females), 23 to 34 years of age, over a period of 12.5 +/- 3.27 days employing a partial -mouth EG model and in 11 patients (three males and eight females), 20 to 63 years or age, with CG. LDFRs were obtained by S-LDFR or H-LDFR. Results: H-LDFRs were significantly higher than S-LDFRs (P < 0.05). All EG subjects developed gingivitis (PI: 2.77 +/- 0.23; GI: 1.5 +/- 0.53). EG-LDFRs at diseased sites increased slightly but not significantly over the study period. All CG-patients had high plaque and inflammation scores (PI: 2.8 +/- 0.2; GI: 1.63 +/- 0.78). CG-LDFRs at sites with GI > 1 were significantly higher than LDFRs at healthy sites (P < 0.05). CG-LDFRs were significantly higher than EG-LDFRs at sites with a comparable GI (P < 0.05). Conclusions: LDFRs are positively correlated with the degree of gingival inflammation. GBF demonstrated significant differences in EG and CG. Modifications of the probe are needed to enhance its clinical applicability in clinical research of periodontal diseases.