Articles and Position Statements
AADC Opinion Statement: Core Build-ups

Core Buildups

Opinion Statement


In past position papers authored by the AADC Positions Committee, the position statements were based on research of a significant number of studies reported in the scientific and professional publications. This paper, however, will not state a position of the AADC but rather an opinion due to a current lack of evidence-based research on what has become one of the more common procedures in restorative dentistry. Our opinion is based on the expertise and observations of AADC Position Committee members as well as research from the few articles written on the subject.

Core buildups are a care issue with significant financial ramifications. In the last twenty years there has been a reported increase in the number of core buildups submitted to dental benefit plans out of proportion to the increase in crown submissions. While the ratio should never reach 1:1, the gap appears to be closing. Placing core buildups under
most crowns is a growing trend and appears to be encouraged by some dental educators. Also growing are the numbers of dentists who admit, with no compunction, that they place core buildups under every crown they seat regardless of need.

The financial ramifications from this trend are significant since a core buildup can add twenty to thirty percent to the final cost for a crown. This additional expense impacts the patient, available insurance benefit dollars, future plan renewal rating data, the plan purchaser and the benefits company. It also has the opposite impact on the provider and
has become, for some, a surcharge added to every crown submission.

What exactly is a core buildup and how does it differ from a crown filler? For purposes of our discussion we will limit the scope to vital teeth only. Teeth that have been treated endodontically and restored with posts and cores is a topic for future research and discussion. A core buildup is described in CDT 2009 - 2010 under codes D2950 (designated for use in conjunction with single crowns) and D6973 (designated for use in conjunction with fixed prosthetic retainers) as:

.... building up of anatomical crown when restorative crown will be placed
whether or not pins are used. A material is placed in the tooth preparation for a
crown when there is insufficient tooth strength and retention for the crown
procedure. This should not be reported when the procedure only involves a filler
to eliminate any undercut, box form or concave irregularity in the preparation.

The descriptor does not address what parameters are used to determine insufficient tooth strength and how much tooth structure is necessary to retain a crown. Gordon Christensen DDS, MSD, PhD, ScD, regarded as one of the most renowned authorities on dental materials and clinical practice, has addressed these questions in several articles published over the years in JADA. Dr. Christensen suggests that the tooth involved be prepped as ideally as possible. All remaining restorative material should then be removed if any doubt exists about retention and underlying pathology. An assessment should then be made of the remaining tooth structure. If more than 50% of the prepped coronal tooth is missing and there is not at least a two to three millimeter collar of sound tooth structure remaining at the gingival margin, a core buildup should be added. The material used for the buildup should be strong with the ability to bond with the underlying tooth. Bonded composite resin material is the most popular and effective used today. This procedure is billed separately from the crown under CDT codes D2950 or D6973. If retentive pins are used, they are to be considered part of the buildup and not billed separately.

If restorative material is used to fill irregularities, remaining box form or to reduce casting bulk, it falls into the category of a crown filler. This material requires less strength than that used for core buildup and should be considered part of the crown procedure and therefore not billed separately. The codes D2950 and D6973 are not appropriate for this procedure. Bonded compomer is a common material used today for crown fillers.

Since some dentists fail to differentiate between a core buildup and a filler, it behooves a dental consultant to ask for documentation that justifies the requested benefit. It is up to the individual plan consultant to determine what type of documentation is cost effective and fair to all parties, be it radiographs, photographs, narratives or any combination. As
noted before, the current trend shows a significant increase in core buildup submissions. If we agree with Dr. Christensen in his JADA 2003 article, the reverse should be true. He points out that with the development of better adhesive cements, the minimum amount of tooth structure required to support a crown is less than in years past. This means we should be seeing fewer rather than more core buildups.

Our goal as consultants should be to educate providers on the difference between core buildup and a crown filler. Dentists who fail to or won’t submit claims that accurately reflect these differences should be closely monitored.

References

1. Christensen, G., When to use fillers, build-ups or posts and cores; JADA, Volume 127, September 1996, 1397-1398

2. Christensen, G., Building Up Tooth Preparations for Crowns-2000; JADA, Volume 131, April 2000, 505-506 
3. Christensen, G., Ensuring retention for crowns and fixed prostheses; JADA, Volume 134, July 2003, 993-995
4. Christensen, G., Direct restorative materials- What goes where?; JADA, Volume 134, October 2003, 1395-1397
5. Christensen, G., Post concepts are changing; JADA, Volume 135, September 2004, 1308-1310
6. Christensen, G., Frequently encountered errors on tooth preparations for crowns; JADA, Volume 138, October 2007, 1373-1375
7. Furlong, A., ADA, NADP share views on dentist’s concerns- part 2; ADA News, January 8, 2007
8. Cheung, W., A review of the management of endodontically treated teeth: Post, core and the final restoration; JADA, Volume 136, May 2005, 611-619
9. Limoli and Associates; Dental Insurance and Reimbursement-Coding and Claim Submission; 9th Edition, 2009; 64-65
10. Shillingburg, H. et al; Fundamentals of Tooth Preparations for Cast Metal and Porcelain Restorations;1987, Quintessence Publishing

AADC Positions Committee

Dr. Jonathan Zucker (Chair)
Dr. Dick Portune (Principal Author)
Dr. Rick Celko
Dr. George Koumaras (Immediate Past President)
Dr. Robert Laurenzano (Founder)
Dr. Stephanie Lepsky
Dr. Clay Pesillo
Dr. Ed Schooley
Dr. Cary Sun
Dr. Fred Tye
Dr. Michael Weitzner (President)
Dr. Dave Wesley
Dr. Marc Zweig