[The possibility of a standardization of clinical trials concerning materials for root canal obturation]

Clinical trials constitute epidemiologic experiments, in comparable groups of human populations designed to assess the preventive of curative effects of agents or measures. International organizations (FDI, WHO, CIOMS, ISO) have been instrumental in creating uniform methods, so that the findings from different sources can be validly compared. The need for a standardization of clinical trials in dentistry is particularly felt: - by the dental profession in order to make the choice of materials with the best clinically proven qualities - by the manufacturers in order to develop materials of improved clinical quality - by the public health administrators (or social security agencies), in order to either evaluate the benefit of instituted preventive and curative measure or to ascertain the best possible services A centennial history of efforts is shown to have resulted today in a broad international understanding (Table III). 1. The first chapter of this paper presents a review of the principal requirements for controlled clinical trails [8] such as officially adopted by FDI (Table V). 2. The second chapter offers a first-hand apercu of impending recommendations proposed by COMIET in two protocols [11] for the uniform conduct and evaluation of clinical trials of restorative techniques and materials. 2.1 Three standardized forms (A, B: Table IX, and C) serve to uniformly record data of the operative procedures. 2.2 The proposed standardized criteria (Tables X, XI) for the clinical appraisal of distinct materials give the advantage of having been tested already very extensively. 3. A critical review of the proposed protocols [11] reveals the necessity of: 3.1 referring to and coordinating with the already adopted principal requirements for controlled clinical trials. 3.2 generally adopting the excellent guidelines for the conduct of the study and the evaluation of observations (Tables X, XI) 3.3 taking advantage of the possibilities for reducing the recommended sample of 100 paired restorations (200 cavities)--difficult to implement in many countries--by certain measure such as preliminary in-vitro experiments, consideration of results already reported in the literature and a more systematic use of a standardized photographic serial documentation, a topic which will be the object of an ensuing paper.