Rate and pattern of Inter-proximal Dental Attrition

Objectives: Although occlusal and inter-proximal attrition result of diverse etiology and present dissimilar features, both of them progress with age. The objectives of this study are to reveal the rate and pattern of inter-proximal attrition facets (PAF) development with age, and to compare it with occlusal attrition (OA) changes.
Methods: 765 teeth were collected from 255 skulls (aged 18-75 years). Three mandibular teeth (P1P1, P2 and M₁) were examined for PAF size and OA rate.
Results: Inter-proximal and occlusal attrition followed similar patterns of development until the age of 40-45 years, after that age they took different paths: PAF decreased in size (probably due to occlusal attrition), regardless of facet location whereas OA continued to progress. The PAF changes with age differed between premolars and molars, unlike OA which presented similar rate for all teeth studied. While OA scores presented significantly high correlations with age (r=0.55-0.58, P<0.001), PAF area size demonstrated low correlations with age (r≤0.29, P<0.001). Low but significant correlations were found between rate of OA and PAF (r≤0.36, P<0.001).
Conclusions: PAF and OA exhibited different pattern with age. Premolars and molars presented dissimilar PAF development; this is probably due to a unique attrition pattern in the molar teeth, different morphology and force vectors.