120 R. F. SOGNNAES 



lesion itself, might confine the injurious influences to a relatively 

 inert restoration material rather than to the adjacent tooth sub- 

 stance itself. 



In view of the possible "eroding" influences of direct contact 

 between the lip and cheek and certain erosion-prone labial and 

 buccal tooth surfaces, it would be of interest to determine, further- 

 more, whether some thin separating paraffin paper or plastic shield, 

 placed in the oral vestibulum during the night at least, might help 

 to stagnate extreme cases of erosion. 



In our effort to control this peculiar wasting of the teeth, several 

 additional factors merit attention. Among these would be — as indi- 

 cated by what has already been discussed above — elimination of 

 occlusal trauma; evaluation and adjustment of chewing habits; anal- 

 ysis and professional advice regarding consumption of food and 

 drinks; and, first and last, determination of, and when possible 

 improvement in, the patient's general health and well-being. 



Postmortem "Erosion" 



In connection with an extensive study of the developmental 

 quality and histopathology of ancient teeth (Sognnaes, 1956), it 

 was discovered that various postmortem changes including erosions 

 had occurred. 



The investigation was based upon a study of human teeth which 

 date back to eleven periods of historv, paleolithic to recent, and 

 originate from six geographic locations, Palestine, Egypt, Greece, 

 Iceland, Norway, and Central America. 



In terms of numbers of specimens from each source the material 

 was limited, particularly the rare specimens of paleolithic Pales- 

 tinian, predynastic Egyptian, and Old Icelandic teeth. The Greek 

 material contained samples from the longest span of time within 

 one and the same country, ranging from prehistoric to New Greek 

 time. All these Greek specimens were obtained during the Unitarian 

 Service Committee's Medical Mission to Greece in 1948, through 

 the courtesy of Professor John Koumaris, Director of the Anthro- 

 pological Museum of Athens. 



