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Which endodontic access cavity is best? A literature review


The preparation of an access cavity is the first part of endodontic treatment and is a key stage in the healing of both periapical and pulpal infections. It should allow endodontists to remove obstructions in the pulp chamber, locate all canal orifices and clean the entire root canal system with minimum coronal tooth structure removed. This has been done traditionally through establishing straight line access. The development of minimally invasive endodontics aimed to preserve as much of the natural tooth structure as possible, particularly dentine, while undertaking root canal treatment, resulting in the development of other access cavity preparations. This includes conservative, ultra conservative (ninja), truss, guided access, caries-orientated and restorative access cavities. These access cavity preparations also gained popularity due to increased magnification and enhanced lighting, allowing practitioners to visualise the pulpal space in greater detail throughout treatment.

Our current recommendation is to conduct access cavities traditionally rather than conservatively. Ideally, conservative access cavities need magnification, which might not be available for all clinicians. With traditional access cavity, the procedure takes less time and it is more predictable to locate the canal orifices, deliver irrigation effectively, avoid iatrogenic damage with biomechanical preparation and achieve better obturation.

Key points

  • With the rise of minimally invasive access cavities, this manuscript educates readers on the literature, including the benefits and drawbacks of each access cavity design and whether minimal access cavities are actually suitable.

  • Allows readers to be able to make more informed clinical decisions on which access cavity design to use in different clinical scenarios.

  • Allows readers to understand what the current recommendations are when it comes to access cavities.

  • Provides some information on magnification and lighting options available, aiding in endodontic treatment.

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Authors and Affiliations



Noor Al-Helou, Ammar Ahmed Zaki, Mustafa Al Agha, Emad Moawad and Fadi Jarad discussed, planned and contributed to the final manuscript. Noor Al-Helou led the analysis and manuscript writing.

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Correspondence to Noor Al-Helou.

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The authors declare no conflicts of interest.

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Al-Helou, N., Zaki, A., Al Agha, M. et al. Which endodontic access cavity is best? A literature review. Br Dent J 234, 335–339 (2023).

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