The absence of an age effect on enamel solubility in phosphoric acid

The growing proportion of older Americans and the projections in declining edentulousness in future cohorts of elderly necessitate elucidation of the responses of the aging human dentition to existing restorative techniques. This study investigated the results of the acid etch process as a function of age of specimen donors as well as a function of race, tooth type, and time between extraction and etch. Statistical analysis of data showed no significant effect on solubility by age, race, or length of time from extraction until etch. Molars were significantly less soluble than other teeth. The most frequently observed microscopic texture was an irregular, granular configuration termed 3g. Widely textural variation was observed in each specimen. A possible explanation for the observations is the distribution of prismless enamel. The widespread belief that older teeth are less efficaciously etched may be based on the greater frequency of composite restoration failures in the elderly, which in turn is more likely a factor of restoration size and changes in intraoral environment than of age.