Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Comparative Study
. 2025 Apr 15;25(1):575.
doi: 10.1186/s12903-025-05947-x.

Marginal and internal adaptation and absolute marginal discrepancy of 3D-printed, milled, and prefabricated crowns for primary molar teeth: an in vitro comparative study

Nagehan Aktaş  1 , Yasemin Akın  2 , Mert Ocak  3 , Didem Atabek  2 , Merve Bankoğlu Güngör  4
Affiliations
Comparative Study

Marginal and internal adaptation and absolute marginal discrepancy of 3D-printed, milled, and prefabricated crowns for primary molar teeth: an in vitro comparative study

Nagehan Aktaş et al. BMC Oral Health. .

Abstract

Background: The quality of marginal and internal adaptation plays a crucial role in the clinical longevity of pediatric crowns. This study aimed to evaluate the effect of restoration type (3D-printed, milled, and prefabricated) on the marginal and internal adaptation and absolute marginal discrepancy (AMD) values of crowns for primary molar teeth.

Methods: Three restoration groups were created: 3D-printed resin, milled resin-matrix ceramic, and prefabricated zirconia crowns (n = 10 per group). A typodont tooth was prepared according to the guidelines for prefabricated zirconia crowns and scanned to design restorations. 3D-printed and milled crowns were fabricated from the same design. All crowns were cemented on standardized 3D-printed resin dies with self-adhesive resin cement. Marginal and internal adaptation and AMD values were evaluated using micro-computed tomography (micro-CT) at multiple measurement points. Data were analyzed using one-way analysis of variance (ANOVA) and Tukey HSD tests, with statistical significance set at P < 0.05.

Results: The restoration type significantly influenced the marginal and internal gap and AMD values (P < 0.05). The prefabricated crown group exhibited the highest marginal gap (233.5 ± 33.4 μm) and internal gap (538.6 ± 47.4 μm). The 3D-printed group showed the highest AMD value (299.5 ± 70.2 μm). The milled group demonstrated the lowest gap values, which remained within clinically acceptable limits.

Conclusions: Prefabricated zirconia crowns displayed the highest marginal and internal gaps, whereas milled crowns exhibited the most favorable adaptation values within clinically acceptable limits. Given their superior adaptation, CAD-CAM-produced restorations may be a recommendable alternative for pediatric patients.

Keywords: 3D-printed crowns; Absolute marginal discrepancy; CAD-CAM restorations; Internal adaptation; Marginal adaptation; Micro-CT analysis; Pediatric dentistry; Prefabricated zirconia crowns; Primary teeth.

PubMed Disclaimer

Conflict of interest statement

Declarations. Ethics approval and consent to participate: It is not necessary. Competing interests: The authors declare no competing interests. Consent for publication: Not applicable. Clinical Trial Number: Not applicable.

Figures

Fig. 1
Fig. 1
Sagittal and coronal sections of the Micro-CT images
Fig. 2
Fig. 2
View of the gaps on the Micro-CT image (Arrows are showing the measurement points; M: marginal, A: axial, and O: occlusal)
See this image and copyright information in PMC

References

    1. Alrashdi M, Ardoin J, Liu JA. Zirconia crowns for children: A systematic review. Int J Paediatr Dent. 2022;32:66–81. - DOI - PubMed
    1. American Academy of Pediatric Dentistry. Pediatric restorative dentistry. The reference manual of pediatric dentistry. Chicago, Ill.: American Academy of Pediatric Dentistry; 2023. pp. 443–56.
    1. MacLean JK, Champagne CE, Waggoner WF, Ditmyer MM, Casamassimo P. Clinical outcomes for primary anterior teeth treated with preveneered stainless steel crowns. Pediatr Dent. 2007;29:377–81. - PubMed
    1. Waggoner WF. Restoring primary anterior teeth: updated for 2014. Pediatr Dent. 2015;37:163–70. - PubMed
    1. Gill A, Garcia M, Won An S, Scott J, Seminario AL. Clinical comparison of three esthetic Full-Coverage restorations in primary maxillary incisors at 12 months. Pediatr Dent. 2020;42:367–72. - PubMed

Publication types

LinkOut - more resources