DENTAL HARD TISSUE DESTRUCTION 



113 



invasion. At present this question is being pursued further at the 

 ultrastructural level. Preliminary electron microscopic observations 

 suggest that a peculiar form of large, dense crystals appears to be 

 precipitated within the dentinal tubules in erosion (Frank and 

 Sognnaes, unpublished). 



Oral Environment 



The above observations leave open the question as to the impor- 

 tance of some oral environmental effects, other than mechanical 

 friction, as potential etiological factors in this peculiar type of 

 idiopathic tooth erosion. There are few studies which have directly 

 endeavored to determine whether agents potentially capable of 

 demineralizing the tooth surface may be present in the oral envi- 

 ronment in general, or in proximity to the lesion of dental erosion 

 in particular, 



Bodecker ( 1933 ) employed a simple clinical method of testing 

 the environment next to the eroded lesions by means of wedges of 

 litmus paper. These he inserted into the gingival sulci in juxtaposi- 

 tion to the eroded area, on the theoretical premise that there may be 

 some acidic product of gingival inflammation which may contribute 

 to the erosion. The latest tabulation of his findings ( Bodecker, 1945 ) 

 has been summarized in Table II. From his qualitative observations 

 Bodecker inferred that the environment in juxtaposition to dental 

 erosion more commonly tends to fall on the acidic side. In contrast, 

 he concluded that the environment around normal teeth, especially 

 in the younger age group, tends to be more on the alkaline side. 



TABLE II. Simple Litmus Paper Determinations of Relative Acidity 



AT THE Sites of Dental Erosion versus Normal Control Teeth 



(From data of Bodecker, 1945) 



