Should smear layer be kept or removed from root canal?

Smear layer removal is still controversial since many years. Many researchers argue about the benefits of smear layer removal on the clinical outcome of endodontic therapy success. However, many researchers found out that the presence of smear layer in the root canal does not affect the outcome of root canal treatment. In addition, some researchers reported better results when smear layer was not removed. This argument among general practitioners, endodontists, and researchers indicates that there is still not a winner or loser and the dilemma of whether to keep or remove the smear layer before root canal obturation requires special attention and analysis in order to select the best treatment scenario according to the present case, as each case should be treated individually after balancing the pros and cons of keeping the smear layer or getting rid of it.