This study was conducted to assess the usefulness of the gingival crevicular blood for estimating the glucose level during routine periodontal examination using Xitux Diagnostics Smart-X self-monitoring blood glucose device among Jordanian patients attending dental teaching clinics. A total of 34 type 2 diabetic patients (18 males and 16 females) and 26 non-diabetic patients (14 males and 12 females) participated in this study. Glucose level was measured in a sample of gingival crevicular blood and in another sample obtained by finger puncture using a self-monitoring device. Glucose measurements from gingival crevicular blood samples, ranged from 57 to 250 mg dl-1 with a mean of 125.4+/-60.7 mg dl-1 (+/-SD) and glucose measurements obtained by finger puncture, ranged from 62 to 263 mg dl-1 with a mean of 131.9+/-61.1 mg dl-1. Pearson's correlation coefficient was performed to assess the correlation between the glucose measurements in these two samples. Pearson's correlation coefficient showed an almost perfect positive correlation between the gingival readings and finger-puncture readings (r=0.997, P<0.0001). In conclusion, gingival crevicular blood can provide an acceptable source for measuring blood glucose level. However, the technique to obtain an acceptable blood sample from gingival crevices is not always feasible which would limit its application as a clinical practice. Additional studies that refine this technique and use larger sample size are recommended.