What it Means to be the Gold Standard

In medicine, a “Gold standard” customarily refers to the clinical model, method, procedure, intervention, or measurement of known validity and reliability, which is generally taken to be the best available, against which new tests or results and protocols are compared. It is evaluated through the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients. Objectively weighing information to determine its value as evidence is crucial to determining what may qualify as a Gold standard. This objective evaluation, however, can be disregarded through a logical fallacy known as argumentum ad antiquitatem: an appeal to tradition. This is a claim in which a concept is deemed correct on the basis of its correlation with past tradition, often taking the form of “this is right because we’ve always done it this way.” An appeal to tradition essentially makes two assumptions:
  • The old way of thinking was proven correct when introduced; since the old way of thinking was prevalent, it was necessarily correct.

In reality, this may be false—the tradition might be entirely based on incorrect grounds.

  • The past justifications for the tradition are still valid.

In reality, the circumstances may have changed; this assumption may also therefore have become untrue.

Unfortunately, this logical fallacy has found its way into how we define the “Gold standard” in bone grafting and implant dentistry. Many factors go into choosing the best bone graft material for your patients. Most clinicians are trained that autografts are the gold standard and allografts are an acceptable alternative. That may have been true 10 years ago, but science has evolved, and studies now prove that beta tricalcium phosphate granules are equal to or superior than the performance of both allografts and autografts.

Below is a list of studies that support these findings:

The study compared a modern βTCP (beta tricalcium phosphate) to a mineralized freeze dried bone allograft and a xenograft (Bio-Oss), including an ungrafted control. At 12 weeks:

  • “It was obvious that βTCP granules were deconstructed to a sufficient degree, with signs of both dissolution of the βTCP particles and direct cellular resorption. These granules were predominantly embedded in the newly formed bone which was more interconnected than at 8 weeks, with signs of bone remodeling.”
  • “In addition, the bovine and human allograft exhibited osseous integration with mature bone, …though particles seemed relatively intact, almost without evidence of absorption and bone substitution.”
These statements are the critical findings. Normal bone resorption and normal bone formation is described for βTCP in addition to the βTCP producing more bone. The authors recognize that cadaver bone does not resorb and there is no bone remodeling evident. This is the definition of sclerotic bone. Not only was there no remodeling of the graft particles, there was no remodeling of the surrounding newly formed bone. When using cadaver bone grafts, the bone present at 12 weeks is permanent and will not remodel for the life of the patient.

This ridge split study found that beta tricalcium phosphate granules produced statistically superior results over allograft granules for all particle sizes. In addition, larger particles (1-2mm) performed superior to smaller particles (.5-1 mm).

Both autograft and beta tricalcium phosphate grafts produced adequate bone for implant placement and both materials had a 100% implant success rate after one year.

This was a critical size defect in sheep that found a third-generation beta Tricalcium phosphate yielding significantly more bone production than autograft and BMP2.

Sinuses were grafted with beta tricalcium phosphate with simultaneously placed implants. This group was compared to maxillary posterior implants that were placed without the need to do sinus augmentation. Both groups experienced 99% success rate after approximately 30 months.

Modern beta tricalcium phosphate bone grafts perform as well or better than allografts or autografts. The negatives of autograft morbidity and cadaver harvesting makes high performing βTCP a superior choice.

  • Beta tricalcium phosphate alone performed better than βTCP when combined with autograft and better than autograft alone.

Our profession continues to outwardly endorse evidence based dentistry, but completely ignores the science when it comes to bone grafting. For more on the topic of βTCP outperforming allograft, xenograft, and the identification of sclerotic bone, read the following articles:


American Society for Bone and Mineral Research (ASBMR)

Tissue Engineering and Regenerative Medicine International Society (TERMIS)

American Academy of Implant Dentistry (AAID)