3-D interferometric microscopy applied to the study of buccal enamel microwear

Abstract

Dental microwear analysis is based on the assumption that a correlation exists between ingested diet and microwear patterns on the enamel surface of teeth, such that diet can be reconstructed by quantifying enamel microwear. Abrasive particles, such as plant phytoliths or silica-based sands incorporated into food items, along with food processing techniques and tooth morphology, are responsible for the microwear features observed. Dental microwear has been extensively studied in both extant and extinct primates, including human populations. The dietary and ecological information that can be derived from dental microwear analyses makes it a technique useful for analyzing non-primate species, such as muskrats, sheep, bats, moles, antelopes, pigs and even dinosaurs. In the attempt to reconstruct species’ ecology and diet, microwear research has become a successful procedure. The proliferation and persistence of different methods to quantify microwear patterns require very accurate definitions of microwear variables, since inter-observer error rates cannot be neglected. The use of semiautomatic methods to quantify microwear features does not guarantee low inter-observer error affecting dental microwear results. Error can be caused by taphonomy, microscopy drawbacks of back-scattered electrons, or differences in SEM reproducibility depending on sample shape and orientation. However, fully automatic procedures lack discrimination between ante-mortem and post-mortem wear processes that affect tooth enamel at various degrees, and their application requires experienced control and evaluation.