Review

The Effect of Manufacturing Technique on Marginal Gap in Inlay, Onlay, Veneer, and Endocrown Restorations: A Systematic Review and Meta-Analysis

Volume: 60 Number: 1 July 8, 2026
EN

The Effect of Manufacturing Technique on Marginal Gap in Inlay, Onlay, Veneer, and Endocrown Restorations: A Systematic Review and Meta-Analysis

Abstract

Purpose

The purpose of this systematic review and meta-analysis was to compare the marginal fit of indirect partial restorations, such as inlays, onlays, and endocrowns, fabricated using milling (subtractive manufacturing) and 3D printing (additive manufacturing) techniques.

Materials and methods

This review was conducted according to the PRISMA guidelines and utilized the PICO framework to define the research question. A comprehensive literature search was performed on PubMed, Scopus, and Web of Science databases for studies published in English between January 1, 2015, and April 1, 2025. The search targeted studies that directly compared milled and 3D-printed indirect partial restorations and reported marginal gap values in a numerical format. Statistical analysis was performed using a random-effects model, and outcomes were synthesized using the Standardized Mean Difference (SMD) with 95% Confidence Intervals (CI).

Results

A total of 16 studies, comprising 257 milled samples and 287 3D-printed samples, were included in the meta-analysis. The overall pooled analysis found no statistically significant difference in marginal gap values between milled and 3D-printed partial restorations (p = 0.62). However, subgroup analyses revealed varying trends. For occlusal veneers, milled restorations showed a smaller marginal gap than 3D-printed restorations; however, this difference was not statistically significant (SMD = –1.86, 95% CI: –18.24 to –14.53, p = 0.39). Conversely, inlays and onlays showed a nonsignificant trend favoring 3D printing (SMD = 0.87, 95% CI: -0.26 to 2.00, p = 0.11).

Conclusion

This systematic review and meta-analysis conclude that there is no overall statistically significant difference in marginal fit between milled and 3D-printed indirect partial restorations.

Keywords

References

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Details

Primary Language

English

Subjects

Dental Materials and Equipment, Prosthodontics

Journal Section

Review

Publication Date

July 8, 2026

Submission Date

July 25, 2025

Acceptance Date

November 29, 2025

Published in Issue

Year 2026 Volume: 60 Number: 1

APA
Alawawda, O., Binici, E., Akıncı, İ., & Bayındır, F. (2026). The Effect of Manufacturing Technique on Marginal Gap in Inlay, Onlay, Veneer, and Endocrown Restorations: A Systematic Review and Meta-Analysis. European Oral Research, 60(1), 176-184. https://doi.org/10.26650/eor.20261751100
AMA
1.Alawawda O, Binici E, Akıncı İ, Bayındır F. The Effect of Manufacturing Technique on Marginal Gap in Inlay, Onlay, Veneer, and Endocrown Restorations: A Systematic Review and Meta-Analysis. EOR. 2026;60(1):176-184. doi:10.26650/eor.20261751100
Chicago
Alawawda, Osayd, Ensar Binici, İlginsu Akıncı, and Funda Bayındır. 2026. “The Effect of Manufacturing Technique on Marginal Gap in Inlay, Onlay, Veneer, and Endocrown Restorations: A Systematic Review and Meta-Analysis”. European Oral Research 60 (1): 176-84. https://doi.org/10.26650/eor.20261751100.
EndNote
Alawawda O, Binici E, Akıncı İ, Bayındır F (July 1, 2026) The Effect of Manufacturing Technique on Marginal Gap in Inlay, Onlay, Veneer, and Endocrown Restorations: A Systematic Review and Meta-Analysis. European Oral Research 60 1 176–184.
IEEE
[1]O. Alawawda, E. Binici, İ. Akıncı, and F. Bayındır, “The Effect of Manufacturing Technique on Marginal Gap in Inlay, Onlay, Veneer, and Endocrown Restorations: A Systematic Review and Meta-Analysis”, EOR, vol. 60, no. 1, pp. 176–184, July 2026, doi: 10.26650/eor.20261751100.
ISNAD
Alawawda, Osayd - Binici, Ensar - Akıncı, İlginsu - Bayındır, Funda. “The Effect of Manufacturing Technique on Marginal Gap in Inlay, Onlay, Veneer, and Endocrown Restorations: A Systematic Review and Meta-Analysis”. European Oral Research 60/1 (July 1, 2026): 176-184. https://doi.org/10.26650/eor.20261751100.
JAMA
1.Alawawda O, Binici E, Akıncı İ, Bayındır F. The Effect of Manufacturing Technique on Marginal Gap in Inlay, Onlay, Veneer, and Endocrown Restorations: A Systematic Review and Meta-Analysis. EOR. 2026;60:176–184.
MLA
Alawawda, Osayd, et al. “The Effect of Manufacturing Technique on Marginal Gap in Inlay, Onlay, Veneer, and Endocrown Restorations: A Systematic Review and Meta-Analysis”. European Oral Research, vol. 60, no. 1, July 2026, pp. 176-84, doi:10.26650/eor.20261751100.
Vancouver
1.Osayd Alawawda, Ensar Binici, İlginsu Akıncı, Funda Bayındır. The Effect of Manufacturing Technique on Marginal Gap in Inlay, Onlay, Veneer, and Endocrown Restorations: A Systematic Review and Meta-Analysis. EOR. 2026 Jul. 1;60(1):176-84. doi:10.26650/eor.20261751100