Graphene-based dental adhesive with anti-biofilm activity

BACKGROUND: Secondary caries are considered the main cause of dental restoration failure. In this context, anti-biofilm and bactericidal properties are desired in dental materials against pathogens such as Streptococcus mutans. To this purpose, graphene based materials can be used as fillers of polymer dental adhesives. In this work, we investigated the possibility to use as filler of dental adhesives, graphene nanoplatelets (GNP), a non toxic hydrophobic nanomaterial with antimicrobial and anti-biofilm properties. RESULTS: Graphene nanoplatelets have been produced starting from graphite intercalated compounds through a process consisting of thermal expansion and liquid exfoliation. Then, a dental adhesive filled with GNPs at different volume fractions has been produced through a solvent evaporation method. The rheological properties of the new experimental adhesives have been assessed experimentally. The adhesive properties have been tested using microtensile bond strength measurements (µ-TBS). Biocidal activity has been studied using the colony forming units count (CFU) method. The anti-biofilm properties have been demonstrated through FE-SEM imaging of the biofilm development after 3 and 24 h of growth. CONCLUSIONS: A significantly lower vitality of S. mutans cells has been demonstrated when in contact with the GNP filled dental adhesives. Biofilm growth on adhesive-covered dentine tissues demonstrated anti-adhesion properties of the produced materials. µ-TBS results demonstrated no significant difference in µ-TBS between the experimental and the control adhesive. The rheology tests highlighted the necessity to avoid low shear rate regimes during adhesive processing and application in clinical protocol, and confirmed that the adhesive containing the 0.2%wt of GNPs possess mechanical properties comparable with the ones of the control adhesive

A Systematic Review of Recall Regimen and Maintenance Regimen of Patients with Dental Restorations. Part 2: Implant-Borne Restorations

Purpose To evaluate the current scientific evidence on patient recall and maintenance of implant-supported restorations, to standardize patient care regimens and improve maintenance of oral health. An additional purpose was to examine areas of deficiency in the current scientific literature and provide recommendations for future studies. Materials and Methods An electronic search for articles in the English language literature from the past 10 years was performed independently by multiple investigators using a systematic search process. After application of predetermined inclusion and exclusion criteria, the final list of articles was reviewed to meet the objectives of this review. Results The initial electronic search resulted in 2816 titles. The systematic application of inclusion and exclusion criteria resulted in 14 articles that satisfied the study objectives. An additional 6 articles were added through a supplemental search process for a total of 20 studies. Of these, 11 were randomized controlled clinical trials, and 9 were observational studies. The majority of the studies (15 out of 20) were conducted in the past 5 years and most studies were conducted in Europe (15), followed by Asia (2), South America (1), the United States (1), and the Middle East (1). Results from the qualitative data on a combined 1088 patients indicated that outcome improvements in recall and maintenance regimen were related to (1) patient/treatment characteristic (type of prosthesis, type of prosthetic components, and type of restorative materials); (2) specific oral topical agents or oral hygiene aids (electric toothbrush, interdental brush, chlorhexidine, triclosan, water flossers) and (3) professional intervention (oral hygiene maintenance, and maintenance of the prosthesis). Conclusions There is minimal evidence related to recall regimens in patients with implant-borne removable and fixed restorations; however, a considerable body of evidence indicates that patients with implant-borne removable and fixed restorations require lifelong professional recall regimens to provide biological and mechanical maintenance, customized for each patient. Current evidence also demonstrates that the use of specific oral topical agents and oral hygiene aids can improve professional and at-home maintenance of implant-borne restorations. There is evidence to demonstrate differences in mechanical and biological maintenance needs due to differences in prosthetic materials and designs. Deficiencies in existing evidence compel the forethought of creating clinical practice guidelines for recall and maintenance of patients with implant-borne dental restorations

Factores relacionados al fracaso de implantes dentales

Introduction: The dental implant is a dental solution that helps the aesthetics of the human being, especially those people who have a missing tooth. This treatment must have surgical planning and adequate prosthesis to avoid failure. Objective: To determine the most common factor related to the failure of dental implants and to identify what percentage prevails more over early and late failures. Methodology: review of articles and documents related to the topic on factors related to dental implant failure. Bases such as Pubmed and Scielo will be used. The research covered the periods from 2015 to 2020 and the PRISMA checklist was used to execute the review. Results: five articles were selected. All reported different factors on the failure of dental implants or prostheses: however, there were 2 articles that agreed that they were due to the osseointegration factor. Conclusion: the osseointegration process was identified as the most frequent cause of dental failures (early phase).Introducción: El implante dental es una solución odontológica que ayuda a la estética del ser humano, sobre todo aquellas personas que tienen un diente faltante. Este tratamiento debe tener planeación quirúrgica y prótesis adecuada para evitar fracasos. Objetivo: Determinar el factor más común relacionado al fracaso de implantes dentales e Identificar qué porcentaje prevalece más sobre los fracasos tempranos y tardíos. Metodología: revisión de artículos y documentos relacionados al tema sobre los factores relacionados al fracaso de implantes dentales. Se utilizaron bases como Pubmed y Scielo. La investigación cubrió los periodos del 2015 hasta 2020 y se utilizó la lista de comprobación PRISMA para ejecutar la revisión. Resultados: cinco artículos fueron seleccionados. Todos reportaban diferentes factores sobre el fracaso de implantes o prótesis dental: sin embargo, hubo 2 artículos que coincidían que se debía al factor de osteointegración. Conclusión: se identificó que el proceso de osteointegración fue la causa más frecuente de los fracasos dentales (fase temprana)

Factores relacionados al fracaso de implantes dentales

Introduction: The dental implant is a dental solution that helps the aesthetics of the human being, especially those people who have a missing tooth. This treatment must have surgical planning and adequate prosthesis to avoid failure. Objective: To determine the most common factor related to the failure of dental implants and to identify what percentage prevails more over early and late failures. Methodology: review of articles and documents related to the topic on factors related to dental implant failure. Bases such as Pubmed and Scielo will be used. The research covered the periods from 2015 to 2020 and the PRISMA checklist was used to execute the review. Results: five articles were selected. All reported different factors on the failure of dental implants or prostheses: however, there were 2 articles that agreed that they were due to the osseointegration factor. Conclusion: the osseointegration process was identified as the most frequent cause of dental failures (early phase).Introducción: El implante dental es una solución odontológica que ayuda a la estética del ser humano, sobre todo aquellas personas que tienen un diente faltante. Este tratamiento debe tener planeación quirúrgica y prótesis adecuada para evitar fracasos. Objetivo: Determinar el factor más común relacionado al fracaso de implantes dentales e Identificar qué porcentaje prevalece más sobre los fracasos tempranos y tardíos. Metodología: revisión de artículos y documentos relacionados al tema sobre los factores relacionados al fracaso de implantes dentales. Se utilizaron bases como Pubmed y Scielo. La investigación cubrió los periodos del 2015 hasta 2020 y se utilizó la lista de comprobación PRISMA para ejecutar la revisión. Resultados: cinco artículos fueron seleccionados. Todos reportaban diferentes factores sobre el fracaso de implantes o prótesis dental: sin embargo, hubo 2 artículos que coincidían que se debía al factor de osteointegración. Conclusión: se identificó que el proceso de osteointegración fue la causa más frecuente de los fracasos dentales (fase temprana)

The Evolution of Dental Composites: A Preventative Approach to Restoration Failure

This study investigates the problem of restoration failure using research data from primary and secondary sources. The failure of dental composites due to secondary caries is very common, so the creation of a restorative material that will serve as a multifactorial solution will be a significant advancement. An enhanced composite material with antibacterial properties and remineralization properties could be the solution to restoration failure. This composite contains dimethylaminododecyl methacrylate (DMADDM) which has antibacterial properties and the remineralizing effect of amorphous calcium phosphate (NACP). Studies have shown that the combination of NACP and DMADDM is a promising new technology that could increase the longevity of dental restorations and provides several potential benefits for both clinicians and patients. Along with its inhibitory properties, the new composite material is also aesthetically pleasing and could potentially be used in all areas and surfaces of the clinical dentition. Composite failure is a prevalent issue and having a longer lasting dental material would certainly be in the patient’s best interest. Our project intends to take a step forward by not only recognizing a problem (primary and secondary caries) and seeking a better solution (enhanced composite fillings), but to plan for the future by incorporating a preventive strategy where dental hygienists could inform and advocate for their patients

Clinical longevity of intracoronal restorations made of gold, lithium disilicate, leucite, and indirect resin composite:a systematic review and meta-analysis

OBJECTIVES: The aim of this systematic review and meta-analysis is to assess the comparative clinical success and survival of intracoronal indirect restorations using gold, lithium disilicate, leucite, and indirect composite materials.MATERIAL AND METHODS: This systematic review and meta-analysis were conducted following the Cochrane Handbook for Systematic Reviews of Interventions and PRISMA guidelines. The protocol for this study was registered in PROSPERO (registration number: CRD42021233185). A comprehensive literature search was conducted across various databases and sources, including PubMed/Medline, Embase, Cochrane Library, Web of Science, ClinicalTrials.gov, and gray literature. A total of 7826 articles were screened on title and abstract. Articles were not excluded based on the vitality of teeth, the language of the study, or the observation period. The risk difference was utilized for the analyses, and a random-effects model was applied. All analyses were conducted with a 95% confidence interval (95% CI). The calculated risk differences were derived from the combined data on restoration survival and failures obtained from each individual article. The presence of heterogeneity was assessed using the I2 statistic, and if present, the heterogeneity of the data in the articles was evaluated using the non-parametric chi-squared statistic (p &lt; 0.05).RESULTS: A total of 12 eligible studies were selected, which included 946 restorations evaluated over a minimum observation period of 1 year and a maximum observation period of 7 years. Results of the meta-analysis indicated that intracoronal indirect resin composite restorations have an 18% higher rate of failure when compared to intracoronal gold restorations over 5-7 years of clinical service (risk difference =  - 0.18 [95% CI: - 0.27, - 0.09]; p = .0002; I2 = 0%). The meta-analysis examining the disparity in survival rates between intracoronal gold and leucite restorations could not be carried out due to methodological differences in the studies.CONCLUSIONS: According to the currently available evidence, medium-quality data indicates that lithium disilicate and indirect composite materials demonstrate comparable survival rates in short-term follow-up. Furthermore, intracoronal gold restorations showed significantly higher survival rates, making them a preferred option over intracoronal indirect resin-composite restorations. Besides that, the analysis revealed no statistically significant difference in survival rates between leucite and indirect composite restorations. The short observation period, limited number of eligible articles, and low sample size of the included studies were significant limitations.CLINICAL SIGNIFICANCE: Bearing in mind the limitations of the reviewed literature, this systematic review and meta-analysis help clinicians make evidence-based decisions on how to restore biomechanically compromised posterior teeth.</p

Graphene-based nanomaterials for tissue engineering in the dental field

The world of dentistry is approaching graphene-based nanomaterials as substitutes for tissue engineering. Apart from its exceptional mechanical strength, electrical conductivity and thermal stability, graphene and its derivatives can be functionalized with several bioactive molecules. They can also be incorporated into different scaffolds used in regenerative dentistry, generating nanocomposites with improved characteristics. This review presents the state of the art of graphene-based nanomaterial applications in the dental field. We first discuss the interactions between cells and graphene, summarizing the available in vitro and in vivo studies concerning graphene biocompatibility and cytotoxicity. We then highlight the role of graphene-based nanomaterials in stem cell control, in terms of adhesion, proliferation and differentiation. Particular attention will be given to stem cells of dental origin, such as those isolated from dental pulp, periodontal ligament or dental follicle. The review then discusses the interactions between graphene-based nanomaterials with cells of the immune system; we also focus on the antibacterial activity of graphene nanomaterials. In the last section, we offer our perspectives on the various opportunities facing the use of graphene and its derivatives in associations with titanium dental implants, membranes for bone regeneration, resins, cements and adhesives as well as for tooth-whitening procedure

Evaluation of the dental structure loss produced during maintenance and replacement of occlusal amalgam restorations

The aim of this in vitro study was to evaluate four different approaches to the decision of changing or not defective amalgam restorations in first primary molar teeth concerning the loss of dental structure. Ditched amalgam restorations (n = 11) were submitted to four different treatments, as follows: Control group - polishing and finishing of the restorations were carried out; Amalgam group - the ditched amalgam restorations were replaced by new amalgam restorations; Composite resin group - the initial amalgam restorations were replaced by composite resin restorations; Flowable resin group - the ditching around the amalgam restorations was filled with flowable resin. Images of the sectioned teeth were made and the area of the cavities before and after the procedures was determined by image analysis software to assess structural loss. The data were submitted to ANOVA complemented by the Student Newman Keuls test (p < 0.05). The cavities in all the groups presented significantly greater areas after the procedures. However, the amalgam group showed more substantial dental loss. The other three groups presented no statistically significant difference in dental structure loss after the re-treatments. Thus, replacing ditched amalgam restorations by other similar restorations resulted in a significant dental structure loss while maintaining them or replacing them by resin restorations did not result in significant loss

Reliability, failure probability, and strength of resin-based materials for CAD/CAM restorations

Objective: This study investigated the Weibull parameters and 5% fracture probability of direct, indirect composites, and CAD/CAM composites. Material and Methods: Discshaped (12 mm diameter x 1 mm thick) specimens were prepared for a direct composite [Z100 (ZO), 3M-ESPE], an indirect laboratory composite [Ceramage (CM), Shofu], and two CAD/CAM composites [Lava Ultimate (LU), 3M ESPE; Vita Enamic (VE), Vita Zahnfabrik] restorations (n=30 for each group). The specimens were polished, stored in distilled water for 24 hours at 37°C. Weibull parameters (m= modulus of Weibull, σ0= characteristic strength) and flexural strength for 5% fracture probability (σ5%) were determined using a piston-on-three-balls device at 1 MPa/s in distilled water. Statistical analysis for biaxial flexural strength analysis were performed either by both one-way ANOVA and Tukey's post hoc (α=0.05) or by Pearson's correlation test. Results: Ranking of m was: VE (19.5), LU (14.5), CM (11.7), and ZO (9.6). Ranking of σ0 (MPa) was: LU (218.1), ZO (210.4), CM (209.0), and VE (126.5). σ5% (MPa) was 177.9 for LU, 163.2 for CM, 154.7 for Z0, and 108.7 for VE. There was no significant difference in the m for ZO, CM, and LU. VE presented the highest m value and significantly higher than ZO. For σ0 and σ5%, ZO, CM, and LU were similar but higher than VE. Conclusion: The strength characteristics of CAD/ CAM composites vary according to their composition and microstructure. VE presented the lowest strength and highest Weibull modulus among the materials