A one-year randomized trial in the Journal of Dentistry compared definitive 3D-printed resin crowns with monolithic zirconia crowns on posterior teeth. Marginal fit, periodontal outcomes and patient satisfaction did not differ significantly, but the resin crowns wore far more and fractured more often numerically. The authors urge caution with resin as a definitive posterior restoration and call for longer-term studies.
A new randomized trial compares definitive 3D-printed crowns with zirconia over one year, and the result is mixed. As of November 2026, this study adds a head-to-head comparison on a question that matters to any practice that prints crowns: can a printed resin crown serve as the final restoration on a posterior tooth? For dentists in Toronto and across Ontario, the useful part of the paper is not a yes or no. It is where the failures clustered.
What did the 3D-printed crown trial test?
The paper, by Shin, Oh and Kim, appears in the Journal of Dentistry (volume 176) and was first published online on October 7, 2026. Fifty-six adults who needed a tooth-supported posterior single crown were randomized 1:1 to a 3D-printed resin crown or a monolithic zirconia crown.
The authors measured:
- Marginal and internal gaps before cementation, using the replica technique
- Occlusal wear, from intraoral scans taken at one week and one year
- Crown fractures
- Periodontal outcomes
- Patient satisfaction
This article is based on the abstract indexed in Europe PMC. The abstract does not name the resin or the printer, so its results should not be assumed to apply to every printable crown material.
What did the trial find on fractures and wear?
Six resin crowns and two zirconia crowns fractured. One-year fracture-free survival was 78.6% for resin (95% confidence interval, 58.4% to 89.8%) and 92.9% for zirconia (95% CI, 74.3% to 98.2%). That difference was not statistically significant (P=0.12).
Wear was a clearer separation. Resin crowns showed a wear depth of 92.33 ± 69.81 μm against 14.48 ± 7.95 μm for zirconia, and a wear volume of 4.31 ± 3.68 mm³ against 0.47 ± 0.31 mm³ (P<0.05). By our arithmetic, that is roughly six times the depth and nine times the volume.
Why does tooth position matter for printed crowns?
Seven of the eight fractures occurred on the most-posterior restored teeth, and that status was associated with fracture incidence (P=0.002). This is the most actionable finding in the abstract, though it covers only eight events across both materials, so it does not establish a safe zone further forward.
Pro Tip: Record whether each printed crown is the most-posterior restored tooth when you place it. It takes seconds, and it lets you review your own fracture pattern at the one-year recall against this trial's.
Where did 3D-printed crowns hold up?
Marginal and axial gaps did not differ significantly between the groups, and axio-occlusal and occlusal gaps were smaller for resin (P<0.05). Periodontal outcomes and patient satisfaction also did not differ significantly. The authors describe the marginal adaptation of the printed crowns as acceptable.
So marginal fit, periodontal outcomes and satisfaction did not favour zirconia in this trial. The significant disadvantage for resin was occlusal wear, and the authors raise concerns about mechanical durability. Short-term satisfaction says little about the longer-term durability of a restoration that showed greater wear in its first year, which is why the authors' call for longer follow-up matters.
How should Ontario dentists read a non-significant fracture result?
Carefully, in both directions. A P value of 0.12 does not show that resin and zirconia survive equally well. With 56 participants and eight fractures, the confidence intervals are wide and overlap heavily, so a real difference could remain undetected. Equally, the numerically higher fracture count does not prove resin is worse.
The authors' own wording is measured: the greater wear and numerically higher fracture incidence "may raise concerns" about mechanical durability, and longer-term studies are required before broader clinical application. Their clinical significance statement says the findings warrant caution and support continued monitoring of wear and restoration integrity.
What should your practice do with this evidence?
One trial of an unnamed resin material does not settle material selection. It does suggest some practical questions for a practice in Mississauga, Markham or anywhere else that uses, or is considering, printed definitive crowns:
- Case selection: Weigh this trial's clustering of fractures on the most-posterior teeth when you discuss a printed crown for that position.
- Informed consent: Explain that this trial followed patients for one year, and that resin wore more than zirconia in it.
- Recall: Plan to check wear and restoration integrity at recall, in line with the authors' monitoring advice.
- Regulatory check: Check the regulatory status of the specific resin you use. Health Canada's Medical Devices Active Licence Listing (MDALL) can be searched by company or device name for Class II, III and IV devices, while Class I devices do not appear in it, so a missing listing does not by itself tell you a device's status; ask the manufacturer. Read the manufacturer's indications too, to confirm the material is indicated for a definitive posterior crown.
Pro Tip: If you already place printed crowns, take an intraoral scan about a week after delivery and again at one year. This trial measured wear from scans taken at one week and one year, and your own series will tell you more about your material than any abstract can.
EBIKO Dental will continue monitoring clinical evidence on digital restorative materials as longer follow-up data appear. More dental industry news and resources for Canadian practices are available at EBIKO Dental.
Sources
- Shin H, Oh KC, Kim JH. Evaluation of full-veneer crowns fabricated with 3D printing resin material for definitive prostheses: A 1-year randomized controlled prospective study. Journal of Dentistry, vol. 176
- Europe PMC record, PMID 42843776
- Health Canada: Medical Devices Active Licence Listing (MDALL)
Frequently Asked Questions
Q: Are 3D-printed resin crowns as durable as zirconia crowns?
This one-year trial does not show that they are. Resin crowns wore significantly more, and six fractured against two zirconia crowns, although the survival difference was not statistically significant (P=0.12). The authors say longer-term studies are required.
Q: Which teeth had the most fractures in the 3D-printed crown trial?
The most-posterior restored teeth. Seven of the eight fractures across both materials occurred there, and that status was associated with fracture incidence (P=0.002).
Q: Do patients like 3D-printed crowns less than zirconia?
This trial found no significant difference in patient satisfaction or periodontal outcomes between the groups.