Correlation of noncarious cervical lesion size and occlusal wear in a single adult over a 14-year time span

Statement of problem. Noncarious cervical lesions are described as having a multifactorial cause, with occlusal trauma and toothbrush abrasion frequently mentioned as major factors. Finite element modeling studies have demonstrated a relocalization of occlusal stresses to the cervical area due to flexure of the crown. This may cause microcracking, especially under tensile stresses, that will lead to a loss of enamel and dentin in the cervical region. Clinical confirmation of an occlusal cause for noncarious cervical lesions has been difficult to obtain. Purpose. This study investigated whether occlusal wear was correlated with an increase in the size of noncarious cervical lesions. Material and methods. Loss of contour at occlusal and cervical sites on 3 teeth of a single individual was measured using digital and visualization techniques at 3 time intervals over a 14-year time span. The 1983 baseline casts and 1991, 1994, and 1997 clinical impressions of a single adult patient with existing noncarious cervical lesions were replicated in epoxy. Surfaces of all replicas were digitized with a contact digitizing system. Sequential digitized surfaces were fit together and analyzed using AnSur-NT surface analysis software. Clinical losses of surface contour by volume and depth of the left mandibular first molar and first and second premolars were recorded. Results. Nine measurements of cervical volume loss (range 0.9 to 11.5 mm³) and 9 corresponding measurements of occlusal volume loss (range 0.39 to 7.79 mm³) were made. The correlation between occlusal and cervical volume loss was strong (r²=0.98) and significant (P<.0001). Conclusion. For the single adult patient in this study, there was a direct correlation between occlusal wear and the growth of noncarious cervical lesions.