Title 1.5 to 2 mm of Coronal Dentin Needed for a Crown Buildup
Clinical Question In a patient receiving a crown, how much remaining tooth structure is needed to perform a buildup that will provide adequate crown retention, resistance, and fracture resistance?
Clinical Bottom Line 1.5 to 2 mm of coronal dentin height with a ferrule preparation design is necessary for the survival of a crown after buildup. The literature available is clear that the more remaining residual dentin on the preparation the better the survival of the crown will be. Many studies use 2 mm of dentin height as a minimum value but a 2012 systematic literature review concludes that 1.5 to 2 mm is likely sufficient.
Best Evidence  
PubMed ID Author / Year Patient Group Study type
(level of evidence)
22152612Juloski/ 2012Systematic Review
Key resultsHaving 1.5-2 mm of natural tooth structure prior to buildup is critical to the survival of the crown. Incorporation of a ferrule design further increases fracture resistance and resistance form. 62 articles (lab studies, computer simulations, and clinical trials) were found acceptable for use in the review.
21344836Mancebo/ 201087 human patientsCase Control Study
Key results87 teeth were split into two groups for this study. One group had 2 mm or greater ferrules and the other group had less than 2 mm of residual dentin height. The ferrule group over the three year period had a failure rate of 6.67% compared to 26.20 % failure in the <2 mm of dentin group.
Evidence Search core[All Fields] AND ferrule[All Fields] AND ("tooth crown"[MeSH Terms] OR ("tooth"[All Fields] AND "crown"[All Fields]) OR "tooth crown"[All Fields] OR "crown"[All Fields] OR "crowns"[MeSH Terms] OR "crowns"[All Fields])
Comments on
The Evidence
Juloski SR: The literature review found is a review of articles of low or medium quality since few RCTS or clinical trials have been done on this topic. That being said, the review was comprehensive, detailed, and used 62 separate sources in the analysis.
Applicability Clinicians seeking to perform a crown buildup on a tooth should not expect successful treatment if the tooth in question has less than 1.5 to 2 mm of residual dentin height.
Specialty (General Dentistry) (Prosthodontics) (Restorative Dentistry)
Keywords Core, ferrule, crown, dentin height, buildup
ID# 2439
Date of submission 03/01/2013
E-mail sport@livemail.uthscsa.edu
Author Ian Sport
Co-author(s) e-mail
Faculty mentor William Rose, DDS
Faculty mentor e-mail ROSEW@uthscsa.edu
Basic Science Rationale
(Mechanisms that may account for and/or explain the clinical question, i.e. is the answer to the clinical question consistent with basic biological, physical and/or behavioral science principles, laws and research?)
None available
Comments and Evidence-Based Updates on the CAT
None available