I recently presented a program at the Florida National Dental Convention held in Orlando. A member of the audience came up to me and asked if we teach Captek crowns at Spear Education and what I thought of the fact that Captek crowns result in a 71% reduction in bacteria. I replied that we discuss all restorative modalities at Spear (including ceramo-metal) and that I had not heard of this bacterial effect with Captek crowns. Upon my return to Phoenix I did a PubMed search to research the question. Here is an abstract from an article from the Journal of Periodontal Research:

J Periodontal Res. 2001 Aug;36(4):252-9.
Reduced dental plaque accumulation on composite gold alloy margins.
Goodson J.M., Shoher I., Imber S., Som S., Nathanson D.

Restoration of tooth surfaces with materials that inhibit formation of heavy bacterial plaque accumulations could be important in the treatment of patients with existing oral disease or in reducing the likelihood for periodontal disease. Captek is a dental gold composite material used to produce copings for ceramometal restorations that has been reported to inhibit plaque accumulation. In this study, the oral bacteria of nine periodontally healthy subjects with a total of 42 gold composite copings were sampled. Contralateral teeth with normal tooth surfaces were also sampled as controls. The quantitative presence of forty bacteria was determined in each sample by DNA:DNA hybridization. The results indicated that the porcelain/gold composite alloy coping surfaces had significantly fewer bacteria than the control normal tooth surfaces (71% reduction). The percentage composition, however, did not differ significantly between surfaces.

I pulled the article and read it through. All of the subjects (9 total subjects with 42 gold composite copings placed at least 4 years earlier) in the study had healthy periodontium, and there were several operators. Forty species of bacteria were investigated and thirty-two showed a significantly lower presence on the gold than on natural tooth. The eight species that did not show a reduction were present in very small populations on both gold and teeth.

There are no other articles on PubMed when "Captek" and "bacteria" are searched. It's an interesting finding that elicited little follow-up in real world use. How many of you bought the Caridex machine?