Occlusal analysis of teeth with non-carious cervical lesions: initial findings

The pathogenesis of non-carious cervical lesions (NCCL) has been considered to involve erosion and abrasion, and, more recently, occlusal interferences, with such lesions being termed abfractions. However, the effect of occlusion has not been quantified. Objectives: This study examines the occlusion on teeth with abfractions in order to further elucidate the aetiology of these lesions. Methods: Ethical approval was obtained. Patients whose teeth exhibited abfractions, and control patients with no NCCL were recruited to participate in the study. Complete upper and lower arch impressions were taken of these patients, their occlusion recorded and casts mounted on an adjustable articulator. The depth of the NCCL was measured and the occlusion, including guidance, centric stops, interferences in lateral and protrusive movements, recorded on the articulated casts using a specially designed proforma. Presence/absence of tooth wear was also recorded. A group of control patients with no abfractions were also recruited. Results: 51 teeth with abfractions in 36 patients were assessed. Analysis of the occlusion of these 51 teeth indicated that 2 had occlusal interferences in lateral excursive movements. 25 of the 36 patients had teeth which showed signs of tooth wear, and in 9 cases the wear affected the tooth with the abfraction lesion. Twenty control cases were also assessed to date. Of these, 10 showed signs of tooth wear and 3 had posterior interferences in lateral and protrusive excursions. Conclusions: Abfractions do not appear to be associated with occlusal interferences, but may be more likely to occur in patients with tooth wear. The support of NHS R&D (North West) is acknowledged.