Factors influencing the failure of dental glass ionomer luting cement due to contraction

Glass ionomer cement used to fix a post within the root of a tooth undergoes cohesive failure on setting. This study aimed to determine the importance of humidity, substrate material and post design on cement failure. Nine groups of five specimens were prepared: groups 1–3 addressed the influence of post design and sectioning process on cement failure, while groups 4–9 examined the interaction between the cement, substrates and humidity. Replicas were prepared of all specimens and viewed using scanning electron microscopy. It was concluded that humidity and substrate influenced the failure of glass ionomer cement whereas post design did not.