From initial case report to randomized clinical trial through 20 years of research in periodontal therapy.
OBJECTIVE
Case reports (CRs) are often the first publication of a new treatment, but randomized clinical trials (RCTs) are needed to confirm the data. The aim of this study was to evaluate how many therapies published as CRs were followed by RCTs of these therapies over a 20-year period.


METHODS
Two researchers conducted a search through international periodontal journals and found the CRs on periodontal treatments published from 1984 to 1986. Subsequent electronic searches made it possible to verify how many of the treatments published as CRs were also investigated through RCTs over the following 20 years.


RESULTS
Thirty-one different therapies were selected out of the 33 published CRs; 15 (48%) of these 31 treatments were investigated by RCTs over the next 20 years.


CONCLUSIONS
As 52% of the CRs were not validated by RCTs, practitioners should view their results with caution.
Nieri
Michele
M
Department of Periodontology, Dental School, University of Florence, Florence, Italy. michelenieri@gmail.com
Saletta
Daniele
D
Buti
Jacopo
J
Pagliaro
Umberto
U
Guidi
Luisa
L
Rotundo
Roberto
R
Prato
Giovanpaolo Pini
GP
D015706:Bibliometrics; D018865:Dental Research / Q000379:methods*; D006801:Humans; D017063:Outcome Assessment, Health Care / Q000379:methods*; D010510:Periodontal Diseases / Q000628:therapy*; D016032:Randomized Controlled Trials as Topic; D054928:Validation Studies as Topic