Chen – Zirconia Crowns and the Evidences of Support-Chen – Zirconia Crowns and the Evidences of Support

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Video Summary

Anna Chen, a pediatric dentistry researcher at Loma Linda University, presents an evidence-based review of prefabricated primary zirconia crowns and the cements used with them. She compares four brands (EZPedo, NuSmile ZR, Kinder Krown, and Cheng/Chen Crown), highlighting design features meant to improve seating and retention—such as internal grooves/threads, modified contours for space loss, try-in “pink” crowns (NuSmile), and “less prep” options (Kinder Krown). She emphasizes that zirconia crowns are aesthetic and durable but cannot be crimped, making fit and cement choice crucial.<br /><br />A major theme is how aggressive tooth preparation must be compared with stainless steel crowns. Studies show zirconia preparations remove significantly more tooth structure, with no statistically significant differences in reduction among brands. Common seating errors stem from inadequate reduction at line angles and buccal bulges, especially on first primary molars. A Loma Linda study also suggests rounding line angles may not significantly affect fracture resistance for prefabricated zirconia crowns.<br /><br />Strength testing shows brand differences depending on testing methods, but all zirconia crowns exceed typical children’s maximum bite force, so fractures are unlikely clinically. Color stability studies demonstrate zirconia can still discolor, especially with prolonged exposure to staining drinks (grape juice, syrups, chocolate milk, cola). Glazed surfaces look better initially, but glaze can wear off within months, making long-term appearance similar to polished surfaces.<br /><br />For retention, testing indicates conventional glass ionomer cement performed best overall and is also the least expensive per crown, while some resin and specialty cements cost more without better retention. Clinical longevity data are limited (mostly up to ~2 years), but presented cases show healthy gingival response and good retention. Reimbursement and material costs vary widely, and many Medicaid programs do not cover zirconia crowns.

Keywords

prefabricated primary zirconia crowns

pediatric dentistry

zirconia crown cementation

glass ionomer cement retention

EZPedo zirconia crowns

NuSmile ZR try-in pink crowns

Kinder Krown less prep option

Cheng Chen Crown design features

tooth preparation reduction vs stainless steel crowns

color stability and staining of zirconia crowns