Zirconia Crown Cementation — ORE Part 1 MCQ
Instant feedback + full explanation. One question, done properly.
Educational content. Not a substitute for clinical judgement or local policy.
Reveal the answer and explanation
Correct answer: E — Resin-modified glass ionomer cement (RMGIC)
Explanation lettering: D = shown as A · E = shown as D · A = shown as E
RMGIC is the best choice when adequate retention form is present. A 24-month randomized clinical trial demonstrated RMGIC achieved 100% success for zirconia-fused-ceramic crowns overall, and crucially maintained 100% success for anterior crowns at two years compared to only 83.3% for conventional GIC. RMGIC offers biocompatibility, fluoride release (beneficial for vital teeth), and does not require ceramic surface pretreatment. Option C (resin cement with total-etch bonding) is flawed because zirconia lacks the glass phase necessary for traditional phosphoric acid etching; effective zirconia bonding requires mechanical treatment (sandblasting) plus MDP-based primers, not total-etch protocols. Options B and D (zinc phosphate and polycarboxylate) are non-adhesive but inferior in microleakage control and lack bioactivity. Option E (temporary ZOE cement) is explicitly temporary and inappropriate for definitive restorations. The discriminating factor is that adequate retention form makes adhesive bonding unnecessary; in this scenario, RMGIC's proven clinical durability, ease of use, and biological benefits make it superior to resin cements despite the latter's superior microleakage control in laboratory studies.
Reference: Craig R, McKenna G (2025) What role do luting cements play in zirconia crown survival? Commentary on Torres C et al. Oper Dent. 50:144–156. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12474542/