Fitness of self-glazed zirconia onlays using conventional and digital impressions

ABSTRACT

The fitness of self-glazed zirconia (SGZ) onlays fabricated with computer-aided design/computer-aided manufacturing was analysed, and conventional impressions (CIs) were compared with intraoral digital impressions (DIs). Onlay preparation was applied on a typodont left mandibular first molar to create 22 copy dies, which were divided into DI and CI groups. The marginal gap of DI-fabricated onlays was smaller than that of CI-fabricated onlays (p < 0.05). In both groups, the marginal gap was larger in the distal gingival than in other regions (p < 0.05), and a trend of decreasing marginal accuracy after thermal cycling was observed. SGZ onlays performed well for internal fitness; the overall internal gaps were 72.05 ± 8.16 and 100.96 ± 22.53 μm in Groups DI and CI, respectively. SGZ onlays exhibited clinically acceptable marginal and internal fitness values. The marginal adaptation of DI-fabricated onlays was better than that of CI-fabricated onlays.

KEYWORDS:

• Self-glazed zirconia
• onlay
• fitness
• digital impression

Acknowledgements

The authors thank Erran Tech Ltd. for manufacturing the onlays via wet deposition.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was supported by the National Natural Science Foundation of China [grant numbers 52111530189 and 51772007].