News Feature

Core Build-Up: Resin Composite Core Build-Ups and Post Cementation

Article by Peter Schouten

The restoration of endodontically treated teeth often requires the use of core build-ups to provide a foundation for the final restoration. Historically, root posts served as a common method to enhance retention and stability for core build-ups. However, resin composite materials have gained popularity for core build-ups due to their excellent aesthetics, adhesive properties, and versatility. As the reinforcement of the remaining tooth structure (and replacing the missing tooth structure) remains fundamental, the decision to use a root post is a subject of ongoing debate.

This article aims to explore several key factors related to restoring endodontically treated teeth using resin composite with or without the introduction of a root post.

HISTORY

Core build-ups with a root post originally used metal as a post material for their strength. Stainless steel, titanium, and gold were popular choices. However, concerns about potential complications like root fractures prompted a shift in treatment philosophy.

The advent of adhesive dentistry brought about the rise of resin composite core build-ups, offering a less invasive and more conservative alternative. The possibility of bonding restorative materials to dental tissue reduced the need to remove sound dental tissue. This shift in perspective allows for a more conservative approach, prioritizing tooth preservation while still providing sufficient strength and retention for long-term success.

POST OR NO POST

Preserving as much tooth structure as possible is a general prerequisite in modern dentistry. Therefore, omitting the use of a post must be considered, especially in cases where root dentine must be sacrificed to create sufficient space and access to insert the post. The decision to use a post should consider the following factors:

The amount and quality of the remaining tooth structure*
The presence of a ferrule effect
The clinician's experience

*Several studies suggest that in cases where an adequate amount of tooth structure remains and when the remaining tooth structure is of good quality, root posts may not be necessary.

THE AMOUNT AND QUALITY OF THE REMAINING TOOTH STRUCTURE

Preserving as much dental tissue as possible is the first requirement. The presence of at least two intact axial walls is considered ideal for optimal clinical outcomes. Teeth with no- or only one residual wall appear to have reduced survival rates compared to teeth with more than one wall.

THE PRESENCE OF A FERRULE EFFECT

The ferrule effect refers to the presence of a circumferential band of tooth structure encircling the coronal portion of the tooth. This effect has been shown to contribute significantly to the resistance of the restored tooth to fracture. Minimal ferrule dimensions are not set in stone. Some general recommendations can be given to help evenly distribute forces, resist occlusal forces, and give enough retention. The ferrule should ideally extend at least 2 mm above the cementoenamel junction, have a circumferential width of approx. 1 mm and a thickness of 1 to 1.5 mm. Finally, the axial walls should have a slight taper towards the occlusal plane.

Would you like to continue reading as a PDF? Please leave your email address below.