Access Cavity Preparations: Classification and Literature Review of Traditional and Minimally Invasive Endodontic Access Cavity Designs

Several endodontic access cavity designs have been proposed in the past decade to access the root canal space in a minimally invasive manner. The rationale for this approach was derived from the assumption that preserving more tooth structure during access preparation will improve the tooth’s resistance to fracture and its long-term survivability. However, is this assumption valid? Also, can this approach compromise other treatment-related aspects? We conducted a literature review using 4 online databases and classified the access cavity designs presented in each article according to our proposed classification. Through the literature search, we identified 49 articles that evaluated the effect of the access cavity design on 11 different treatment parameters. The majority of the studies failed to demonstrate clear benefits of the minimally invasive access designs, whereas others raised concerns regarding the ability to adequately disinfect, fill, and restore teeth with a minimally invasive access cavity design. Minimally invasive access cavity designs present more risk than benefit on the outcome of endodontic treatment. Clinicians should reconsider the application of a minimally invasive access cavity for routine endodontics and cautiously apply it in selected cases when the proper armamentarium is available.