For himself and co-workers: S. F. ERPF, M. G. HENNINGSEN, and
W. W. WAINWRIGHT.]
Statements to the effect that salivary composition is or is not related to the occurrence of caries do not seem to be tenable, owing to inadequacy of the reported data. Increased viscosity of saliva is paralleled by increase in caries frequency. Marked fluctuations in incidence of caries may occur in any person during a single year, and are related to seasonal changes. The greatest and least incidences of caries have been observed during the winter and summer seasons, respectively.
A literary survey, and study of technical procedures for determinations of calcium and phosphorus in saliva, have shown that for calcium only four publications contained adequate reports and results for the establishment of normal standards and for comparison with salivas of patients having caries ; for phosphorus, only three reports were acceptable. In a dento-medical investigation of twenty-six patients (mostly adults), with life caries-indices (Biidecker) of 0 to 1.875 percent, the physical findings were essentially negative, excepting minor complaints obviously unassociated with caries. Dental examinations yielded the following percentage data : Occlusal grooves: deep, 91.3 ; shallow, 8.7. Horizontal or vertical atrophy of paradental bone structure: none, 34.62 ; horizontal, 34.62; horizontal and vertical, 30.76. Pulp stones: none, 76.92; single and multiple, 23.08. Calculus formation: none, 34.61; calculus, 53.85; extreme calculus, 11.54.
References: J. Den. Res., 1934, 1938, 1939; J. Am. Den. Assoc.(Den. Cosmos), 1938; Ergebnisse neuerer Speichel Untersuchungen mit besonderer Beriicksichtigung der Graviditdt and der Paradentosen, 1929 (Hermann Meuser, Berlin).