VALIDITY AND REPRODUCIBILITY OF CLINICAL EXAMINATION, FIBEROPTIC TRANSILLUMINATION, AND BITE-WING RADIOLOGY FOR THE DIAGNOSIS OF SMALL APPROXIMAL CARIOUS LESIONS - AN IN-VITRO STUDY

This study measured validity and reproducibility of unaided clinical d iagnosis, fibre-optic transillumination (FOTI), and bite-wing radiolog y in the diagnosis of approximal caries. Sixty models were made using extracted premolars and molars, each containing four teeth with six co ntacting approximal surfaces. The teeth were examined first using unai ded clinical examination and then using FOTI. Bite-wing radiographs we re then taken of the teeth set in the models and examined. The three e xaminations were repeated after 1 week. Histological sections of the u ndecalcified teeth were prepared following their removal from the mode ls, and those showing signs of caries were examined to give the valid state of disease in each surface. The diagnostic threshold was caries penetrating into dentine. The reproducibility of all three methods was acceptable with kappa values exceeding 0.6. All specificity values ex ceeded 0.95. Statistically significant differences were seen between s ensitivities for clinical (0.38) and bite-wing (0.59) diagnosis and be tween clinical and FOTI (0.67) examination, but not between bite-wing and FOTI. It is concluded that the validity of FOTI is at least as hig h as that of bite-wing radiology, and both are superior to unaided cli nical diagnosis.