Fig. 2From: Serum 25-hydroxyvitamin D is negatively associated with severe periodontitis: a cross-sectional studyComparison of serum 25-hydroxyvitamin D value between non-severe periodontitis and severe periodontitis group by non-parametric test (F = 27.9, p < 0.05). The bottom and top edges of each box represent the first and third quartiles, respectively, the band within the box represents the median valueBack to article page