Gingival crevicular fluid alkaline phosphatase levels in postmenopausal women: Effects of phase I periodontal treatment

Background: The aim of this study was to determine how estrogen status may possibly influence gingival crevicular fluid (GCF) alkaline phosphatase (ALP) levels in estrogen-deficient (ED) and -sufficient (ES) postmenopausal women at baseline (BL) and 1 year after periodontal phase I treatment (AT). Methods: Thirty-six postmenopausal women on estrogen supplements (mean serum estradiol levels > 30 pg/ml; estrogen sufficient) and 37 postmenopausal women not on estrogen supplements (mean serum estradiol levels < 30 pg/ml; ED) were divided into two subgroups as chronic periodontitis and clinically healthy controls after clinical and radiographic examination. The ES group consisted of 19 control (ES/C) and 17 chronic periodontitis (ES/P) patients, and the ED group consisted of 20 control (ED/C) and 17 chronic periodontitis (ED/P) patients. Plaque (PI) and gingival (GI) indices, bleeding on probing (BOP), probing depths (PD), clinical attachment loss (CAL) scores, and GCF samples were recorded at BL and AT. The levels of ALP in the GCF were measured photometrically. The paired samples Student t and Wilcoxon tests were used to compare the ALP levels and clinical parameters between BL and AT. The correlation among the ALP and clinical parameters was analyzed using the Pearson correlation. Results: The mean of all clinical parameters (PI, GI, BOP, PD, and CAL) was significantly (P < 0.05) higher in periodontitis groups (ES/P and ED/P) than controls (ES/C and ED/C). Periodontitis groups (ES/P and ED/P) demonstrated significantly increased GCF volumes and GCF ALP levels (P < 0.05) compared to controls (ES/C and ED/C). There were no significant differences in the concentrations of ALP between periodontitis and control groups (P > 0.05). The BL GCF ALP total levels of the ED/P group were significantly higher than the ES/P group (P < 0.05). The BL and AT serum ALP levels of the ED/P group were not significantly but were numerically higher than the ES/P group. One year after periodontal treatment, the GCF volume, GCF ALP total, and concentrations decreased significantly in both periodontitis groups (P < 0.05). However, the GCF ALP levels were still numerically higher in the ED/P group. A positive statistical correlation was found between total ALP levels and PD (r = 0.621; P < 0.05). Conclusion: These data suggest that the presence of ALP in GCF is not simply a reflection of the local inflammation state and that a patient's estrogen status may possibly influence local ALP levels in GCF.