Human Saliva

Abstract

The mg. % Ca content in 650 individuals varied inversely to the rate of flow (r = -0.156 [plus or minus] 0.038). The lowest rates of flow were accompanied by the highest mg. % Ca values, while above 19 ml./hr. the Ca content remained level. The P content showed a slight inverse relationship to rate of flow (r = [long dash]0.281 [plus or minus] 0.034). The correlation coefficients of all relationships between mg./hr. values (Ca or P or their ratio or product) and ml./hr. were extremely high; e.g., total Ca mg./- hr. and rate of flow, r = +0.913 [plus or minus] 0.006; inorganic P mg./hr. and rate of flow, r = + 0.810 [plus or minus] 0.013; Ca-P product mg./hr. and rate of fow, r = + 0.770 + 0.016; Ca mg./hr. and P mg./hr./r = + 0.783 [plus or minus] 0.016. These high correlations resulted because of the relatively slight relation between mg. % concn. and rate of flow and the fact that the mg./hr. was greatly influenced by the amt. ml./hr. The high correlation between Ca and P mg./hr. values was not due to any high correlation between the minerals but rather to the manner of calculating the mg./hr. value. This was confirmed by an exceedingly low partial correlation coefficient of Ca mg./hr. and P mg./hr. holding rate of flow constant (r 12.3 = + 0.154 [plus or minus] 0.038). The Ca-P ratio was related slightly to rate of flow (r = + 0.238 [plus or minus] 0.037). The Ca-P mg. % product reflected the relationships of these constituents to rate of flow (r = - 0.223 [plus or minus] 0.037).