Registration of dental erosive wear on study models and intra-oral photographs

Clinical photographs and study models may provide permanent records of dental erosion and be useful supplements to clinical registration.

To assess the reliability and validity of registrations on clinical photographs and study models performed by a group of examiners.

Thirty tooth surfaces were selected and assessed clinically, using the visual erosion dental examination system. The chosen surfaces provided the whole range of dental erosions including sound surfaces. The tooth surfaces were photographed and impressions were obtained for preparation of study models. Thirty-three dentists examined and scored the selected surfaces both on photographs and study models.

The quality of diagnosis (AUC, area under curve) was slightly higher using photographs as compared to study models. The difference was statistically significant when the validation criterion was erosion, assuming dentine exposure. The inter-method agreement on photographs and study models versus the clinical evaluation were approximately in the same range with a mean κw of 0.48 and 0.43, respectively. When comparing study models with photographs the mean κw was 0.52. The intra-examiner agreement was strong/substantial for both (photographs mean κw = 0.63 and study models mean κw = 0.60).

Linear weighted Cohen's kappa (κw) was used to evaluate inter-method and intra-examiner agreement. Receiver operating characteristic and area under the curves were used to express diagnostic quality according to a clinical examination.

The results indicated that photographs were as good as study models for recording erosive lesions.