We should always take into consideration the amount of good accomplished
for the patient,--the salvation of the tooth,--and if we are sure, from
experience and observation, that the tin filling will last as long as a
gold one in the same cavity, or longer, then the fee should be as much
as for gold, with the cost of the gold deducted. The amount of the fee
ought to be based upon the degree of intelligence, learning, and skill
required; upon the amount of nervous energy expended; upon the draft
made on the dentist's vitality; upon what benefit has been given the
patient; upon the perfection of the result; and, everything else being
equal, upon the time occupied; the value of this last factor being
estimated in proportion to the shortness of it.