The use of fibre-optic transillumination in the diagnosis of posterior approximal caries in clinical trials.

Abstract

The need to develop alternative techniques other than bitewing radiographs for the diagnosis of caries in clinical trials is discussed and the use of fibre-optic transillumination (FOTI) proposed. A validation study was conducted in which the teeth of 25, 12- to 13-year-old children were examined using a direct-light source, by FOTI and by bitewing radiographs for the presence of dentinal lesions on posterior approximal surfaces. Taking diagnoses from radiographs as the validating criteria, the sensitivity of FOTI was 0.73 and specificity 0.99. A clinical trial involving 224, 12- to 13-year-old children was established to compare the efficacy of two fluoride dentifrices, FOTI being incorporated into the clinical examination. Use of FOTI increased the discriminatory ability of the clinical examination such that the percent caries change in efficacy detected between the two dentifrices rose from 5 to 10% for the DFS index and from 14 to 19% for DMFT. FOTI is proposed as a valid, efficient alternative to bitewing radiographs in clinical trials of caries-prophylactic agents.