Evidence map›Paper›PMID 42277836›Full record

ArticleBMC oral health2026

The internal fit and fracture resistance of stainless-steel crowns and porcelain fused to metal crowns in intact and severely damaged permanent molars: an in vitro study.

Horieh Moosavi, Fatemeh Khorakian, Fatemeh Sedaghati, Ali Abkar, Hamidreza Baradaran Kashani

Abstract readComparative Study
In one paragraph

Article in BMC oral health, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

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0cells of the map it votes in
1citing papers in PubMed
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1 · What the graph read from it

What it found

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3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

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4 · The record

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PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors.

Horieh MoosaviDepartment of Restorative and Cosmetic Dentistry, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran.
Fatemeh KhorakianDepartment of Pediatric Dentistry, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran.
Fatemeh SedaghatiDepartment of Restorative and Cosmetic Dentistry, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran. fateme75493@gmail.com.
Ali AbkarStudent Research Committee, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran.
Hamidreza Baradaran KashaniStudent Research Committee, School of Dentistry, Mashhad University of Medical Sciences, Mashhad, Iran.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

aimSevere caries in mixed dentition frequently affects mandibular first permanent molars, often necessitating full-coverage restorations. Stainless steel crowns (SSCs) and porcelain-fused-to-metal (PFM) crowns are among the most commonly used options. This study aimed to compare the internal fit and fracture resistance of SSCs and PFMs in both intact and restored mandibular first molars. MATERIALS AND

methodsForty extracted mandibular first molars were randomly divided into four groups: (1) intact teeth-SSCs, (2) intact teeth-PFMs, (3) restored teeth-SSCs, and (4) restored teeth-PFMs. In restored samples, access cavities and mesiodistal boxes were prepared and restored with composite resin. Following tooth preparation, PFM crowns were fabricated, and appropriate SSCs were selected. The internal fit was assessed using the silicone replica technique under a digital microscope. Crowns were then cemented with glass ionomer cement, and fracture resistance was measured using a universal testing machine. Data were analyzed using two-way ANOVA, independent t-test, and Chi-square test (α = 0.05).

resultsSSCs demonstrated significantly greater marginal gap (intact: 313.20 ± 44.46 μm; restored: 304.90 ± 62.03 μm), axial gap, and total internal gap compared with PFMs (marginal gap: intact: 183.00 ± 41.29 μm; restored: 222.10 ± 38.25 μm; p < 0.001). Tooth condition had no significant effect on SSC adaptation; however, PFM marginal and total internal gap values increased significantly following restoration (p = 0.048). PFMs demonstrated significantly higher fracture resistance than SSCs under both conditions (p < 0.001). Restored SSCs exhibited significantly higher fracture resistance than intact SSCs (p = 0.029), while no significant difference was observed between intact and restored PFMs. SSCs showed a significantly higher proportion of repairable failures (40-80%) compared with PFMs, in which all fractures were non-repairable (p < 0.001).

conclusionsUnder the conditions of this in vitro study, PFMs demonstrated superior internal adaptation and overall fracture resistance compared with SSCs; however, SSCs exhibited more favorable and repairable fracture patterns. Long-term clinical studies are warranted to validate these findings.

Indexed as

CrownsDental AlloysDental Marginal AdaptationDental PorcelainMetal Ceramic AlloysMolarStainless SteelComposite ResinsDental Prosthesis DesignDental Restoration FailureDental Stress AnalysisHumansIn Vitro TechniquesMaterials TestingComposite ResinsDental AlloysDental PorcelainMetal Ceramic AlloysStainless SteelDental CrownsDental MaterialsMechanical StrengthMetal-Ceramic CrownsStainless Steel

Identifiers

PMID42277836
PMCPMC13479831

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.