牙石是牙龈病和牙周病的主要病因之一。了解牙石形成程度与年令、性别、职业、唾液PH值的关系,对予防或去除牙石以防治上述疾病具有重要意义。我们将1980年3月至9月记载详细的457例洁治病例牙石形成程度与年令、性别、职业、睡液PH值的关系进行了统计分析,现报导如下。 Tartar is one of the major causes of gum disease and periodontal disease. To understand the degree of calculus and age, sex, occupation, saliva pH value, to prevent or remove calculus to prevent the above diseases is of great significance. We conducted a statistical analysis of the relationship between the degree of formation of calculus and the age, sex, occupation, and pH value of sleeping pills recorded in detail from March to September 1980, which are reported as follows.