A comparison of the site-specificity of supragingival and subgingival calculus deposition

The aims of the present study on 40 patients were to quantitate by the Volpe-Manhold method, the amount of supragingival (SPR) calculus, to determine qualitatively the amount of subgingival calculus (SBG), and to determine the association between supragingival and subgingival calculus on vestibular and lingual surfaces of all the teeth except third molars. Kappa values for intraexaminer reproducibility varied between 0.863 and 0.738. There was marked site-specificity of SPR calculus scores, with the highest values by far on the lingual aspects of the lower anterior teeth: central incisor, lateral incisor, and canine, respectively. Although the grades for SBG calculus were higher on the lingual surfaces than on the vestibular surfaces of 25 of the 28 teeth, there was much less site-specificity than for SPR calculus. For the teeth as a whole, there were significant associations (P < 0.001), as tested by chi-square or Fisher's exact test, between SPR and SBG grades on both vestibular and lingual surfaces, between SPR grades on vestibular and lingual surfaces, and between SBG grades on vestibular and lingual surfaces. However, for individual teeth, or groups of similar teeth, only a few of the above associations were statistically significant.