Endodontic access cavity preparation is one of the most crucial steps in the endodontic procedure. It affects all of the steps of endodontic treatment such as the cleaning and shaping, irrigation and obturation. The conventional endodontic access cavity was the only method for preparing access cavity for many years. New technique introduced in the past few years known by many names such as conservative endodontic access cavity and many other names. This technique in access preparation follows the concept of minimal invasive dentistry which aims to preserve tooth structure. Whileconservative endodontic access cavity preparations could increase the fracture resistance of endodontically treated teeth, it may influence the final shape of the prepared root canal.