Create a send email button in a customer record which should available only once for each customer records

We can create button in customer record which can be vanished or disabled after using it for once.

Create a customer.
Add a custom check box to use it as the condition to show or hide the send email button.
Create a workflow and In state 1 added the send email button.
In state 2 send the email using a custom email template and also setting the check box value true to hide the send email button.
When the workflow is run the send email button is displayed in the top of the customer record.
And after using it once it is disappeared for that customer.