Does Finishing and Polishing of Restorative Materials Affect Bacterial Adhesion and Biofilm Formation? A Systematic Review

SUMMARY Biofilm (bacterial plaque) accumulation on the surface of restorative materials favors the occurrence of secondary caries and periodontal inflammation. Surface characteristics of restorations can be modified by finishing and/or polishing procedures and may affect bacterial adhesion. The aim of this systematic review was to characterize how finishing and polishing methods affect the surface properties of different restorative materials with regard to bacterial adhesion and biofilm formation. Searches were carried out in MEDLINE-PubMed, EMBASE, Cochrane-CENTRAL, and LILACS databases. From 2882 potential articles found in the initial searches, only 18 met the eligible criteria and were included in this review (12 with in vitro design, four with in situ design, and two clinical trials). However, they presented high heterogeneity regarding materials considered and methodology for evaluating the desired outcome. Risk bias analysis showed that only two studies presented low risk (whereas 11 showed high and five showed medium risk). Thus, only descriptive analyses considering study design, materials, intervention (finishing/polishing), surface characteristics (roughness and surface free energy), and protocol for biofilm formation (bacterial adhesion) could be performed. Some conclusions could be drawn: the impact of roughness on bacterial adhesion seems to be related not to a roughness threshold (as previously believed) but rather to a range, the range of surface roughness among different polishing methods is wide and material dependent, finishing invariably creates a rougher surface and should always be followed by a polishing method, each dental material requires its own treatment modality to obtain and maintain as smooth a surface as possible, and in vitro designs do not seem to be powerful tools to draw relevant conclusions, so in vivo and in situ designs become strongly recommended.

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Human Adipose-Derived Stromal/Stem Cell Culture and Analysis Methods for Adipose Tissue Modeling In Vitro: A Systematic Review

Cells ◽

10.3390/cells10061378 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1378

Author(s):

Peyton Gibler ◽

Jeffrey Gimble ◽

Katie Hamel ◽

Emma Rogers ◽

Michael Henderson ◽

...

Keyword(s):

Systematic Review ◽

Adipose Tissue ◽

Drug Discovery ◽

3D Culture ◽

Human Adipose Tissue ◽

Culture Methods ◽

Adipose Tissue Engineering ◽

The Impact

Human adipose-derived stromal/stem cells (hASC) are widely used for in vitro modeling of physiologically relevant human adipose tissue. These models are useful for the development of tissue constructs for soft tissue regeneration and 3-dimensional (3D) microphysiological systems (MPS) for drug discovery. In this systematic review, we report on the current state of hASC culture and assessment methods for adipose tissue engineering using 3D MPS. Our search efforts resulted in the identification of 184 independent records, of which 27 were determined to be most relevant to the goals of the present review. Our results demonstrate a lack of consensus on methods for hASC culture and assessment for the production of physiologically relevant in vitro models of human adipose tissue. Few studies have assessed the impact of different 3D culture conditions on hASC adipogenesis. Additionally, there has been a limited use of assays for characterizing the functionality of adipose tissue in vitro. Results from this study suggest the need for more standardized culture methods and further analysis on in vitro tissue functionality. These will be necessary to validate the utility of 3D MPS as an in vitro model to reduce, refine, and replace in vivo experiments in the drug discovery regulatory process.

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Impact of Bacterial Biofilm Formation on In Vitro and In Vivo Activities of Antibiotics

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.42.4.895 ◽

1998 ◽

Vol 42 (4) ◽

pp. 895-898 ◽

Cited By ~ 112

Author(s):

Silvia Schwank ◽

Zarko Rajacic ◽

Werner Zimmerli ◽

Jürg Blaser

Keyword(s):

Animal Model ◽

Staphylococcus Epidermidis ◽

Biofilm Formation ◽

Bacterial Biofilm ◽

Phenotypic Resistance ◽

Vitro Model ◽

The Impact ◽

Isogenic Strains

ABSTRACT The impact of bacterial adherence on antibiotic activity was analyzed with two isogenic strains of Staphylococcus epidermidis that differ in the features of their in vitro biofilm formation. The eradication of bacteria adhering to glass beads by amikacin, levofloxacin, rifampin, or teicoplanin was studied in an animal model and in a pharmacokinetically matched in vitro model. The features of S. epidermidis RP62A that allowed it to grow on surfaces in multiple layers promoted phenotypic resistance to antibiotic treatment, whereas strain M7 failed to accumulate, despite initial adherence on surfaces and growth in suspension similar to those for RP62A. Biofilms of S. epidermidis M7 were better eradicated than those of strain RP62A in vitro (46 versus 31%;P < 0.05) as well as in the animal model (39 versus 9%; P < 0.01).

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Materials Sealing Preventing Biofilm Formation in Implant/Abutment Joints: Which Is the Most Effective? A Systematic Review and Meta-Analysis

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-19-00121 ◽

2020 ◽

Vol 46 (2) ◽

pp. 163-171

Author(s):

Cecília Alves de Sousa ◽

Maria Beatriz Bello Taborda ◽

Gustavo Antônio Correa Momesso ◽

Eduardo Passos Rocha ◽

Paulo Henrique dos Santos ◽

...

Keyword(s):

Systematic Review ◽

Biofilm Formation ◽

Meta Analysis ◽

Significance Level ◽

Gutta Percha ◽

Significant Difference ◽

Physical Barriers ◽

External Connection

The purpose of this systematic review was to evaluate the literature available for materials exhibiting the best efficacy in preventing biofilm formation in the interior of implants. We searched PubMed/MEDLINE, Scopus, and Cochrane databases. This review is registered with the PROSPERO database and followed the suitability of the PRISMA protocol. The initial search resulted in 326 articles from the databases. After they were read, 8 articles remained, and the inclusion and exclusion criteria were applied. Six of these 8 articles were classified as in vitro and 2 were classified as in situ. The regions of the implants evaluated ranged from the interface of the pieces to the occlusal upper access of the abutment. The implant connections evaluated the Morse taper, external connection, and internal connection. Meta-analysis of the quantitative data was performed at a significance level of .05. Cotton exhibited poor control of infiltration, even in combination with other materials. Isolated gutta-percha (GP) and polytetrafluoroethylene (PTFE) tape with composite resin (CR) or GP performed better as physical barriers. The best results for chemical barriers were observed by the application of 1% chlorhexidine gluconate (CG) gel, thymol varnish, and the deposition of Ag films onto the surface. The applied meta-analysis did not show a significant difference in comparison between the different types of implant connections (P > .05). The application of CG and thymol varnish antimicrobials was effective in preventing biofilm formation and easy clinical execution; these could be used in combination with CR, GP, and PTFE.

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Bacterial Adhesion and Biofilm Formation on Direct, Tooth-Colored Restorative Materials: An in vitro Study

Advances in Dentistry & Oral Health ◽

10.19080/adoh.2018.08.555736 ◽

2018 ◽

Vol 8 (3) ◽

Author(s):

Jegdish P Babu

Keyword(s):

Bacterial Adhesion ◽

Biofilm Formation ◽

In Vitro Study ◽

Vitro Study ◽

Restorative Materials

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Phagocytosis and Efferocytosis by Resident Macrophages in the Mouse Pancreas

Frontiers in Endocrinology ◽

10.3389/fendo.2021.606175 ◽

2021 ◽

Vol 12 ◽

Author(s):

Kristel Parv ◽

Nestori Westerlund ◽

Kevin Merchant ◽

Milad Komijani ◽

Robin S. Lindsay ◽

...

Keyword(s):

Confocal Imaging ◽

Mouse Pancreas ◽

Tissue Microenvironment ◽

Inflammatory State ◽

Islet Dysfunction ◽

Diabetes Development ◽

The Impact

The tissue microenvironment in the mouse pancreas has been shown to promote very different polarizations of resident macrophages with islet-resident macrophages displaying an inflammatory “M1” profile and macrophages in the exocrine tissue mostly displaying an alternatively activated “M2” profile. The impact of this polarization on tissue homeostasis and diabetes development is unclear. In this study, the ability of pancreas-resident macrophages to phagocyte bacterial and endogenous debris was investigated. Mouse endocrine and exocrine tissues were separated, and tissue-resident macrophages were isolated by magnetic immunolabeling. Isolated macrophages were subjected to flow cytometry for polarization markers and qPCR for phagocytosis-related genes. Functional in vitro investigations included phagocytosis and efferocytosis assays using pH-sensitive fluorescent bacterial particles and dead fluorescent neutrophils, respectively. Intravital confocal imaging of in situ phagocytosis and efferocytosis in the pancreas was used to confirm findings in vivo. Gene expression analysis revealed no significant overall difference in expression of most phagocytosis-related genes in islet-resident vs. exocrine-resident macrophages included in the analysis. In this study, pancreas-resident macrophages were shown to differ in their ability to phagocyte bacterial and endogenous debris depending on their microenvironment. This difference in abilities may be one of the factors polarizing islet-resident macrophages to an inflammatory state since phagocytosis has been found to imprint macrophage heterogeneity. It remains unclear if this difference has any implications in the development of islet dysfunction or autoimmunity.

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The Impacts of msaABCR on sarA-Associated Phenotypes Are Different in Divergent Clinical Isolates of Staphylococcus aureus

Infection and Immunity ◽

10.1128/iai.00530-19 ◽

2019 ◽

Vol 88 (2) ◽

Author(s):

Joseph S. Rom ◽

Aura M. Ramirez ◽

Karen E. Beenken ◽

Gyan S. Sahukhal ◽

Mohamed O. Elasri ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Biofilm Formation ◽

Clinical Isolates ◽

Protease Production ◽

Relative Impact ◽

Extracellular Proteases ◽

Content Type ◽

The Impact

ABSTRACT The staphylococcal accessory regulator (sarA) plays an important role in Staphylococcus aureus infections, including osteomyelitis, and the msaABCR operon has been implicated as an important factor in modulating expression of sarA. Thus, we investigated the contribution of msaABCR to sarA-associated phenotypes in the S. aureus clinical isolates LAC and UAMS-1. Mutation of msaABCR resulted in reduced production of SarA and a reduced capacity to form a biofilm in both strains. Biofilm formation was enhanced in a LAC msa mutant by restoring the production of SarA, but this was not true in a UAMS-1 msa mutant. Similarly, extracellular protease production was increased in a LAC msa mutant but not a UAMS-1 msa mutant. This difference was reflected in the accumulation and distribution of secreted virulence factors and in the impact of extracellular proteases on biofilm formation in a LAC msa mutant. Most importantly, it was reflected in the relative impact of mutating msa as assessed in a murine osteomyelitis model, which had a significant impact in LAC but not in UAMS-1. In contrast, mutation of sarA had a greater impact on all of these in vitro and in vivo phenotypes than mutation of msaABCR, and it did so in both LAC and UAMS-1. These results suggest that, at least in osteomyelitis, it would be therapeutically preferable to target sarA rather than msaABCR to achieve the desired clinical result, particularly in the context of divergent clinical isolates of S. aureus.

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Thermo-Responsive Hydrogels Based on Methylcellulose/Persian Gum Loaded With Taxifolin Enhance Bone Regeneration: An in Vitro / in Vivo Study

10.21203/rs.3.rs-736612/v1 ◽

2021 ◽

Author(s):

Zahra Sadat Sajadi-Javan ◽

Jaleh Varshosaz ◽

Mina Mirian ◽

Maziar Manshaei ◽

Atousa Aminzadeh

Keyword(s):

Animal Studies ◽

Bone Defects ◽

Halloysite Nanotubes ◽

Thermosensitive Hydrogel ◽

Alizarin Red ◽

The Impact ◽

Responsive Hydrogels

Abstract In-situ forming hydrogels have gained noticeable attention to encapsulate osteogenic agents and regenerate irregular-shape bone defects. In this study, a novel thermosensitive hydrogel based on blended methylcellulose (MC) with Persian gum (PG) was fabricated and enriched with taxifolin (TAX) loaded halloysite nanotubes (HNTs) to enhance mechanical and biological characteristics of the hydrogel in bone tissue engineering. The injectability, mechanical and rheological tests were performed for different hydrogel formulations containing 0.25-1.5 w/v% PG and 1-7 w/v% HNTs. Also, to evaluate the impact of PG and HNTs on hydrogel behavior, the degradation rate and swelling degree of hydrogels were assessed. The optimized MC/PG/HNTs hydrogel containing 1% PG and 3% HNTs (MC/PG-1/HNTs 3%) was easily injectable and gelled rapidly at physiological temperature, while it had the highest mechanical strength due to the existence of PG and HNTs. In vitro release study of TAX from this system also revealed more sustained release compared to HNTs-TAX nanoparticles. Furthermore, the interaction of cells with hydrogel and osteo-conductivity was studied using osteoblast-like cells (MG-63). Results showed higher cell adhesion, proliferation, and gene expression for MC/PG-1/HNTs-TAX hydrogel compared to MC/PG-1 and MC/PG-1/HNTs 3% possibly due to the synergic effect of HNTs and TAX. In addition, Alizarin Red S staining and alkaline phosphatase measurements indicated that the existence of HNTs-TAX promoted osteogenic differentiation. Eventually, animal studies on the femoral defects indicated improved remedy when using the MC/PG-1/HNTs-TAX hydrogel carrying MG-63 cells.

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Truncation of poly-N-acetylglucosamine (PNAG) polymerization with N-acetylglucosamine analogues

10.1101/2021.10.13.464265 ◽

2021 ◽

Author(s):

Zachary Morrison ◽

Alexander Eddenden ◽

Adithya S Subramanian ◽

P. Lynne Howell ◽

mark nitz

Keyword(s):

Biofilm Formation ◽

Chain Termination ◽

Salvage Pathway ◽

Biofilm Inhibition ◽

E Coli ◽

Substrate Analogues

Bacteria require polysaccharides for structure, survival, and virulence. Despite the central role these structures play in microbiology few tools are available to manipulate their production. In E. coli the glycosyltransferase complex PgaCD produces poly-N-acetylglucosamine (PNAG), an extracellular matrix polysaccharide required for biofilm formation. We report that C6-substituted (H, F, N3, SH, NH2) UDP-GlcNAc substrate analogues are inhibitors of PgaCD. In vitro the inhibitors cause PNAG chain termination; consistent with the mechanism of PNAG polymerization from the non-reducing terminus. In vivo, expression of the GlcNAc-1-kinase NahK in E. coli provided a non-native GlcNAc salvage pathway that produced the UDP-GlcNAc analogue inhibitors in situ. The 6-fluoro and 6-deoxy derivatives were potent inhibitors of biofilm formation in the transformed strain, providing a tool to manipulate this key exopolysaccharide. Characterization of the UDP-GlcNAc pool and quantification of PNAG generation support PNAG termination as the primary in vivo mechanism of biofilm inhibition by 6-fluoro UDP-GlcNAc.

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Surface Deterioration of Indirect Restorative Materials

Brazilian Dental Journal ◽

10.1590/0103-6440202002982 ◽

2020 ◽

Vol 31 (3) ◽

pp. 264-271

Author(s):

Amanda Mahammad Mushashe ◽

Isabelli Carolini Farias ◽

Carla Castiglia Gonzaga ◽

Leonardo Fernandes da Cunha ◽

Jack Libório Ferracane ◽

...

Keyword(s):

Surface Characteristics ◽

Ceramic System ◽

Resin Cements ◽

Restorative Materials ◽

Levene Test ◽

Adhesive Cement ◽

Hybrid Ceramic ◽

In Situ Biodegradation

Abstract The objective of this work was to evaluate the effects of in vitro and in situ biodegradation on the surface characteristics of two resin cements and a hybrid ceramic system. One hundred and eighty specimens (4X1.5mm) of each material (Maxcem Elite, NX3 Nexus and Vita Enamic) were made and randomly distributed in twelve groups (n=15) according to the material and biodegradation method. The specimens were then submitted to the following challenges: storage in distilled water 37 ºC for 24 h or 7 days, storage for 7 days, at 37 ºC, in stimulated saliva or in situ. The in situ stage corresponded to the preparation of 15 intraoral palatal devices, used for 7 days. Each device presented 3 niches, where a sample of each materials was accommodated. Specimens from both saliva and in situ groups suffered a cariogenic challenge, corresponding to the application of a solution of 20% of sucrose, 10 times throughout each day. After each biodegradation method, the surface roughness (Ra), Vickers hardness (VHN) and scanning electron microscopy (SEM) analyzes were performed. The data collected were evaluated by Levene test, two-way ANOVA and Tukey`s test (α=5%). The in situ challenge promoted the greater biodegradation, regardless of the material. Regarding the materials, the Vita Enamic VHN was negatively affected by all biodegradation methods and the Nexus NX3 presented better performance than the self-adhesive cement tested. Therefore, within the conditions of this work, it was concluded that in situ biodegradation can affect negatively the surface characteristics of indirect restorative materials.

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