You are a helpful, respectful, and honest assistant. Always answer as helpfully as possible, while being safe. Your answers should not include any harmful, unethical, racist, sexist, toxic, dangerous, or illegal content. Please ensure that your responses are socially unbiased and positive in nature. If a question does not make any sense or is not factually coherent, explain why instead of answering something not correct. If you don't know the answer to a question, please don't share false information.
What is Microabrasion techniques for elimination of discoloration of teeth work by: and explain in detail?
Surface discolorations because of fluorosis can also be removed by microabrasion, if the discoloration is within 0.2 to 0.3 mm removal depth limit.
In 1984, McCloskey reported the use of 18% HCI swabbed on teeth for the removal of superficial fluorosis stains. 
Subsequently, in 1986, Croll modified the technique to include the use of pumice with the HCl to form a paste applied with a tongue blade.