Despite being challenging, the restoration of severely damaged nonvital teeth can be the first treatment option for many practicing dentists. This is because of the various potential functional, psychological, and financial merits of retaining/restoring a tooth versus tooth extraction and prosthetic replacement [1]. Commonly, restoration of endodontically treated teeth (ETT) involves posts and cores and crown restorations of varying designs, materials, and cements/ luting agents [2]. However, when a decision is made to restore an ETT, the long-term prognosis of the contemplated restoration is of paramount importance [3]. In this respect, many factors may play a role in improving the survival and fracture resistance of the restored ETT; these include volume and integrity of the remaining tooth structure, anatomy/morphology of the root canal, position of the tooth in the dental arch, presence of proximal contacts, nature of occlusion, core material, restoration design, ferrule effect, and number of remaining walls [4,5]. Among the former factors, the ferrule effect and number of remaining walls seem to be particularly important [6]. A ferrule effect was introduced by Eissman and Radke [7] to describe the 360-degree ring of cast metal and recommended the extension of the definitive cast restoration at least 2 mm apical to the junction of J Prosthodont Res. 2023; **(**): ****-****