Bacteria in the cavity-restoration interface after varying periods of clinical service - SEM description of distribution and 16S rRNA gene sequence identification of isolates.

Roopinder Kaur Arora, Nicola J Mordan, David A Spratt, Yuan Ling Ng, Kishor Gulabivala

Abstract read

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Article in Clinical oral investigations, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

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2citing papers in PubMed

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1 · What the graph read from it

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

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3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

From Caries to Periodontal Breakdown: A Biological and Clinical Continuum Linking Cariology, Operative Dentistry, Endodontics, and Periodontology.Dentistry journal · 2026
Review
Nano-chitosan modified restorative materials suppress Streptococcus mutans biofilm and virulence gene expression.AMB Express · 2026
Article

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5 · Who and what money

Authors and funding

5 authors.

Roopinder Kaur AroraUnit of Endodontology, Departments of Restorative Dentistry, Microbial Diseases, UCL Eastman Dental Institute, University College London, Bloomsbury Campus, Rockefeller Building, 21 University Street, London, WC1E 6DE, UK.

Nicola J MordanBiomaterials and Tissue Engineering, UCL Eastman Dental Institute, University College London, London, UK.

David A SprattUnit of Endodontology, Departments of Restorative Dentistry, Microbial Diseases, UCL Eastman Dental Institute, University College London, Bloomsbury Campus, Rockefeller Building, 21 University Street, London, WC1E 6DE, UK.

Yuan Ling NgUnit of Endodontology, Departments of Restorative Dentistry, Microbial Diseases, UCL Eastman Dental Institute, University College London, Bloomsbury Campus, Rockefeller Building, 21 University Street, London, WC1E 6DE, UK.

Kishor GulabivalaUnit of Endodontology, Departments of Restorative Dentistry, Microbial Diseases, UCL Eastman Dental Institute, University College London, Bloomsbury Campus, Rockefeller Building, 21 University Street, London, WC1E 6DE, UK. k.gulabivala@ucl.ac.uk.ORCID http://orcid.org/0000-0002-2384-608X

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

objectivesTo use extracted human teeth with amalgam (n = 26) or GIC (n = 3) restorations in service up to 20 years to evaluate microbiota at the cavity/restoration interface by SEM or culture. MATERIALS AND

methodsExtracted teeth with intracoronal restorations (n = 20) of known history (2-20 years) were fixed, split, and prepared for SEM to ascertain the pattern and structure of bacterial aggregates on cavity and restoration surfaces. Another 9 teeth were anaerobically decontaminated, split and sampled (cavity/restorations), and cultured (anaerobically, aerobically); recovered isolates were identified by 16S rRNA gene sequencing.

resultsSEM showed rods, cocci, and filaments in 11/20 teeth (55%) on cavity and corresponding restoration surfaces; 4/20 (20%) on neither surface; 1/20 (5%) on just cavity; and 4/20 (20%) on just restoration. Microbial growth extended from marginal openings into the deeper interfacial microspace to varying extents but was not always evident. Restoration size or age did not predict bacterial presence. Bacteria-free surfaces (cavity/amalgam) showed possible calcification. Cultivation yielded 160 isolates, mainly Gram-positive (86%) and facultative (81%); and morphotypes of rods (43%), cocci (36%), and cocco-bacilli (18%) belonging to Actinobacteria (45%) and Firmicutes (50%). The most frequent genera were Staphylococcus, Streptococcus, Actinomyces, and Lactobacillus. Biofilms on cavity and restoration appeared independent of each other.

conclusionsCavity and amalgam surfaces were independently colonised and some not. The penetration of microbiota into marginal gaps varied; resembled root caries and was dominated by Gram-positive species. CLINICAL RELEVANCE: Marginal gaps around restorations are unavoidable but are not always colonised by bacteria after long-term clinical service. Calcification of biofilms in the restorative interface may prevent further colonisation. The viable microbiota in the restorative interface resembled root caries and may be subject to ecological fluxes of activity and arrest and therefore preventative management.

Indexed as

Dental CariesDental LeakageRoot CariesBacteriaComposite ResinsDental AmalgamDental Cavity PreparationDental Restoration, PermanentGenes, rRNAHumansRNA, Ribosomal, 16SComposite ResinsDental AmalgamRNA, Ribosomal, 16SBacteriaBacterial identificationCavity-amalgam interfaceMicroleakageSEM

Identifiers

PMID35359188

DOI10.1007/s00784-022-04473-2

PMCPMC9276561

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