Factors related to the quantity of subgingival calculus in proximal root surfaces

The aim of this study was to determine the association between the quantity of subgingival calculus and the following factors: type and severity of pe riodontal disease, age, gender and tobacco consumption. A sample of 622 per iodontal patients was studied. The radiographically detectable subgingival calculus in proximal root surfaces was recorded in periapical radiographs, considering the number of surfaces without calculus and the number of surfa ces exhibiting deposits equal or greater than 1 mm. The association between the subgingival calculus and the factors under study was analyzed by disti nct non-parametric tests. A statistically significant association was found between the absence/presence of subgingival calculus and the type and seve rity of periodontal disease (p less than or equal to 0.001), tobacco consum ption (p=0.0049) and age (p less than or equal to 0.001). The quantity of r adiographically-detectable subgingival calculus increased with increasing a ge and severity of the disease. However, the reverse association was found in smokers, which presented more surfaces free of calculus (p=0.0377) and l ess surfaces exhibiting deposits equal or greater than 1 mm. The amount of subgingival calculus decreased as the quantity of tobacco consumed increase d (p=0.0129), and such differences were more significant in those smoker pa tients with severe periodontitis (p= 0.0065). An explanation is presented t o justify these latter findings, since most literature supports that the pr esence of calculus is higher in smokers. According to the results of this s tudy, more radiographically-detectable subgingival calculus in proximal roo t surfaces was found with increasing severity of the disease, with increasi ng age and with the absence of tobacco consumption.