Document bzm4YRBaq3mz6dOLRpLZO5Mo

June 15# 193^ Mr* E. E. Marbaker Research Department Leo S* Smith and Son Mf g, Co* 7525 Penn Avenue Pittsburgh* Pa* Dear Mr* Marbaker: In aa mu c h as I shall he away from the laboratory for the next tmo or three months* I aa replying to your letter of June 12th and turning over the correspondence to m y associate Dr* W* P* Machle* who will be prepared to work out any subsequent development of this matter if it becomes advisable to proceed before I return* In view of the prevailing attitude toward the use of lead containing materials* I should advise against your use of the lead compound for the purpose whlph you have in Blind* if it could b e avoided* I think it probable that the use of lead in the manner you describe would be in no wise hazardous* hut on the other hand* it seems quite probable that its use for this purpose would be questioned* and that if difficulties arose* you would have to b e In position to defend yourself not only against criticism but against dtusage suits* I do not see how protection could be provided except on the basis of experimental work of a very practical sort* In my opinion* it would be advisable to test the solubility of the lead in the "Vlnylite* In various aold and alkaline media* This* it would seem* could be done as well in your laboratory as here* It should also be established* I believe aa to whether there is any appreciable solution or disinte gration of the dentures under conditions of actual uae* The latter would require the cooperation of a sul table subject or subjeots* and the fate of the dentures could be determined cither by determining the residual lead, in them after a definite period of wear* or perhaps by following the lead excretion of the subject with and without the den tures* In any oase* I believe experimental work of this general type should be carried out if you consider it worth while to use this type of denture* and if you desire this type of work* we are In position to carry it out for you* tr B 00137 The cost of such work will depend, of course, upon a number of factor such a the employment of a suitable subject or subjects, the duration of the experi ment, and the number of analyses which might be required to determine the facts* In any case, the cost of this experimentation would run into same hundreds of dollars* It would perhaps be well for you to determine whether such expenditures are justified before we consider the details of the experimentation which might be carried out. I would suggest that you consider the matter and take it up further with Dr* Machle* Very truly yours, RAK IS Robert' A* ftehoe/'M.C.