Dental Sealant Empowered by 1,3,5-Tri Acryloyl Hexahydro-1,3,5-Triazine and α-Tricalcium Phosphate for Anti-Caries Application

Influence of incorporation of nanostructured silver vanadate decorated with silver nanoparticles on roughness, microhardness, and color change of pit and fissure sealants

Objective

The aim of this study was to evaluate the roughness, hardness, and color change of pit and fissure sealants of two commercial brands (Fluroshield ™ and Ultraseal XT ™) incorporated with nanostructured silver vanadate nanomaterial decorated with silver nanoparticles (β-AgVO3) in concentrations (0% - control, 2.5% and 5%).

Material and methods

Two commercial brands Fluroshield TM and Ultraseal XT ™ were used to make the samples with dimensions of 6 × 6 × 4 mm. The control group was made according to the manufacturer's instructions and in the groups with the addition of β-AgVO3, the nanomaterial was added proportionally by mass at percentages of 2.5% and 5%. Roughness properties were evaluated using a 3D Laser Confocal Microscope (n = 10), Knoop microhardness by Microdurometer (n = 10), and color change by Portable Color Spectrophotometer on the CIEDE2000 system (n = 10). Data were evaluated by one-way ANOVA with Bonferroni adjustment and Tukey's mean comparison test at a 5% significance level.

Results

Ultraseal XT ™ sealant roughness showed a significant difference between concentrations with the highest mean for the 5% group (P = 0.010). Regarding the hardness, both sealants showed no significant difference between the groups. Fluroshield ™ sealant showed a significant difference in ΔE00 between the control-2.5% 24.93 (3.49) and control-5% 28.41 (2.58).

Conclusion

It may be concluded that the incorporation of β-AgVO3 influenced the increase in roughness for Ultraseal XT ™ pit and fissure sealant, did not interfere with the microhardness of both sealants, and promoted a change in the color of Fluroshield ™ sealant within clinically acceptable limits.

Antibacterial Effect of Two Novel Sealants: A Laboratory-Based Study

Background

This research sought to assess the impact of polyhexamethylene guanidine hydrochloride (PHMGH) and 1,3,5-triacryloyl hexahydro-1,3,5-triazine (TAT) on the antibacterial activity of an experimental resin sealant.

Materials and Methods

The two experimental sealants were formulated based on previous research, and Streptococcus mutans (S. mutans) was tested for biofilm and planktonic bacteria's antibacterial properties. In 48 hours, 300 L of frozen S. mutans in skim milk was stored in an oven at 37°C in a microaerophilic atmosphere with 5% of CO2 and put on a petri plate containing brain-heart infusion (BHI) broth with agar at 15 g/L. By combining 100 mL of the subculture broth with 900 mL of a sterile saline solution (0.9%) in an Eppendorf tube, the initial inoculum used for the experiments was evaluated. The colonies were measured in colony-forming units per milliliter (CFU/mL) after being counted visually. To measure the antibacterial activity, log CFU/mL was used to express the number of bacteria in the broth that had been in contact with the samples for 24 hours.

Results

Outcomes of antibacterial activity against planktonic bacteria and against biofilm development on polymerized materials. The two innovative sealant materials were found to differ significantly from one another, while group 2's mean and standard deviation values were larger.

Conclusion

Dental sealants designed with PHMGH and TCPTAT for anticaries application showed less bacterial growth throughout time the cavity prevention properties of the resin sealant.

Guided Bone Regeneration Using Barrier Membrane in Dental Applications

Guided bone regeneration (GBR) is a widely used technique in preclinical and clinical studies due to its predictability. Its main purpose is to prevent the migration of soft tissue into the osseous wound space, while allowing osseous cells to migrate to the site. GBR is classified into two main categories: resorbable and non-resorbable membranes. Resorbable membranes do not require a second surgery but tend to have a short resorption period. Conversely, non-resorbable membranes maintain their mechanical strength and prevent collapse. However, they require removal and are susceptible to membrane exposure. GBR is often used with bone substitute graft materials to fill the defect space and protect the bone graft. The membrane can also undergo various modifications, such as surface modification and biological factor loading, to improve barrier functions and bone regeneration. In addition, bone regeneration is largely related to osteoimmunology, a new field that focuses on the interactions between bone and the immune system. Understanding these interactions can help in developing new treatments for bone diseases and injuries. Overall, GBR has the potential to be a powerful tool in promoting bone regeneration. Further research in this area could lead to advancements in the field of bone healing. This review will highlight resorbable and non-resorbable membranes with cellular responses during bone regeneration, provide insights into immunological response during bone remodeling, and discuss antibacterial features.

Antibacterial Effect of Triazine in Barrier Membranes with Therapeutic Activity for Guided Bone Regeneration

Objective: This study aimed to develop polymer-based barrier membranes based on poly(butylene-adipate-co-terephthalate) (PBAT) with the addition of 1,3,5-triacriloilhexahydro-1,3,5-triazine (TAT). Materials and Methods: Polymeric solutions were used to produce membranes with 5 wt% and 10 wt% of TAT by solvent casting. Membranes without the addition of TAT were used as controls. The membranes were chemically characterized by Fourier transform infrared spectroscopy (FTIR) and thermogravimetry (TGA); surface properties were assessed by profilometry and contact angle; the mechanical behavior was evaluated by a tensile test, and the biological properties were assessed by direct−indirect cell viability and antibacterial activity by S. mutans and S. aureus colony-forming units. Results: TAT was detected in the FTIR and TGA analyses and modified the top surface of the membranes, increasing their roughness and wetness in both concentrations compared to the control group (p < 0.05). The addition of TAT, regardless of concentration, reduced the tensile strength and increased membrane stiffness (p < 0.05). The cell viability of 5 wt% TAT and 10 wt% TAT was 86.37% and 82.36%, respectively. All tested concentrations reduced the formation of biofilm on the membranes when compared to the control. Conclusion: The addition of TAT successfully resulted in the antimicrobial ability of PBAT-based barrier membranes, while it maintained acceptable levels of cell viability in membranes with adequate handling and surface properties.

Bioactive Restorative Dental Materials-The New Frontier

Bioactive materials for dental resin restorations are a rising field of investigation exploring treatment strategies for reducing the recurrence of carious lesions. The current effort has been directed toward developing dental materials that can inhibit biofilms and prevent tooth mineral loss. Bioactive resin materials have shown the potential to interfere with polymicrobial consortia in vivo and help maintain the lifespan of restorations.

Minimally Invasive Therapies for the Management of Dental Caries—A Literature Review

In recent years, due to a better understanding of the caries pathology and advances in dental materials, the utilization of non-invasive and minimally invasive techniques that delay/obviate the need for traditional restorations has started gaining momentum. This literature review focuses on some of these approaches, including fluoride varnish, silver diamine fluoride, resin sealants, resin infiltration, chemomechanical caries removal and atraumatic restorative treatment, in the context of their chemistries, indications for use, clinical efficacy, factors determining efficacy and limitations. Additionally, we discuss strategies currently being explored to enhance the antimicrobial properties of these treatment modalities to expand the scope of their application.

Ionic liquid-loaded microcapsules doped into dental resin infiltrants

Resin infiltrants have been effectively applied in dentistry to manage non-cavitated carious lesions in proximal dental surfaces. However, the common formulations are composed of inert methacrylate monomers. In this study, we developed a novel resin infiltrant with microcapsules loaded with an ionic liquid (MC-IL), and analyzed the physical properties and cytotoxicity of the dental resin. First, the ionic liquid 1-n-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (BMI.NTf₂) was synthesized. BMI.NTf₂ has previously shown antibacterial activity in a dental resin. Then, MC-IL were synthesized by the deposition of a preformed polymer. The MC-IL were analyzed for particle size and de-agglomeration effect via laser diffraction analysis and shape via scanning electron microscopy (SEM). The infiltrants were formulated, and the MC-IL were incorporated at 2.5%, 5%, and 10 wt%. A group without MC-IL was used as a control. The infiltrants were evaluated for ultimate tensile strength (UTS), contact angle, surface free energy (SFE), and cytotoxicity. The MC-IL showed a mean particle size of 1.64 (±0.08) μm, shriveled aspect, and a de-agglomeration profile suggestive of nanoparticles' presence in the synthesized powder. There were no differences in UTS among groups (p > 0.05). The incorporation of 10 wt% of MC-IL increased the contact angle (p < 0.05), while the addition from 5 wt% reduced the SFE in comparison to the control group (p < 0.05). The human cell viability was above 90% for all groups (p > 0.05). The incorporation of microcapsules as a drug-delivery system for ionic liquids may be a promising strategy to improve dental restorative materials.

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Ionic liquid was used as core of synthesized polymeric-based microcapsules.

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Microcapsules doped with ionic liquid were incorporated into a dental resin.

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The dental resins presented proper mechanical and biocompatibility properties.

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The particles incorporation reduced the surface free energy of dental resins.

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Biointeractivity may be obtained through MC-IL addition into dental resins.

The Antibacterial Effects of Resin-Based Dental Sealants: A Systematic Review of In Vitro Studies

This review aimed to assess the antimicrobial effects of different antibacterial agents/compounds incorporated in resin-based dental sealants. Four databases (PubMed, MEDLINE, Web of Science and Scopus) were searched. From the 8052 records retrieved, 275 records were considered eligible for full-text screening. Nineteen studies met the inclusion criteria. Data extraction and quality assessment was performed by two independent reviewers. Six of the nineteen included studies were judged to have low risk of bias, and the rest had medium risk of bias. Compounds and particles such as zinc, tin, Selenium, chitosan, chlorhexidine, fluoride and methyl methacrylate were found to be effective in reducing the colony-forming unit counts, producing inhibition zones, reducing the optical density, reducing the metabolic activities, reducing the lactic acid and polysaccharide production and neutralizing the pH when they are added to the resin-based dental sealants. In addition, some studies showed that the antibacterial effect was not significantly different after 2 weeks, 2 months and 6 months aging in distilled water or phosphate-buffered saline. In conclusion, studies have confirmed the effectiveness of adding antibacterial agents/compounds to dental sealants. However, we should consider that these results are based on laboratory studies with a high degree of heterogeneity.

Emerging Contact-Killing Antibacterial Strategies for Developing Anti-Biofilm Dental Polymeric Restorative Materials

Polymeric materials are the first choice for restoring tooth cavities, bonding tooth-colored fillings, sealing root canal systems, and many other dental restorative applications. However, polymeric materials are highly susceptible to bacterial attachment and colonization, leading to dental diseases. Many approaches have been investigated to minimize the formation of biofilms over polymeric restorative materials and at the tooth/material interfaces. Among them, contact-killing compounds have shown promising results to inhibit dental biofilms. Contact-killing compounds can be immobilized within the polymer structure, delivering a long-lasting effect with no leaching or release, thus providing advantages compared to release-based materials. This review discusses cutting-edge research on the development of contact-killing compounds in dental restorative materials to target oral pathogens. Contact-killing compounds in resin composite restorations, dental adhesives, root canal sealers, denture-based materials, and crown cements have all demonstrated promising antibacterial properties. Contact-killing restorative materials have been found to effectively inhibit the growth and activities of several oral pathogens related to dental caries, periodontal diseases, endodontic, and fungal infections. Further laboratory optimization and clinical trials using translational models are needed to confirm the clinical applicability of this new generation of contact-killing dental restorative materials.