of borderline significanceP <0.075
A US cross-sectional study reported that an inverse correlation between dietary calcium intake as assessed by means of a 24-hour dietary recall and periodontal index as assessed based on visual and radiographic data was of borderline significance ( r = -0.24, P <0.075), while serum calcium concentration was not significantly correlated with periodontal index ( r =0.16) [ 6 ].