CAD/CAM post and core for telescopic crowns after fracture.

Abstract

Aim: Fracture of abutment teeth with telescopic crown-retained removable partial dentures (TCDs) is a common cause of failure for this prosthetic restoration. In many cases, a telescopic crown (TC) can only be refitted after post and core (PC) treatment due to an insufficient retention surface. Furthermore, if the root canal has an elliptic cross-sectional area or the coronal defect is severe, customized cast post and cores (CPCs) are still the therapy of choice. Nevertheless, the disadvantage of CPCs is longer chair time due to the need for a second appointment for insertion. In addition, the mechanical properties of the alloy do not match with dentin, leading to a higher risk of root fracture. In such cases, CAD/CAM PCs fabricated in a fully digital chairside workflow can accelerate the treatment and decrease the risk of root fractures by using materials with matching mechanical properties.

Materials and methods: The case series presented in this article includes 12 patients who were treated with TCDs and experienced abutment tooth fracture that required PC treatment to refit TCs. The post space preparation as well as the TCDs were scanned in less than 10 min for the fabrication of CAD/CAM PCs out of a fiber-reinforced CAD/CAM composite.

Conclusions: With the presented fully digital chairside workflow, PC fabrication can be accelerated because a second appointment is not needed for customized PCs. The presented workflow might be an alternative to that for conventional PCs to refit TCs after abutment tooth fracture. The CAD/CAM-fabricated PC offers mechanical properties close to dentin and can be fabricated chairside in a short period of time.