Evaluation of the information provided in the instruction manuals of dental light-curing units.

OBJECTIVE: This study evaluated the completeness and accuracy of information in LCU instruction manuals from 40 manufacturers. MATERIALS AND METHODS: Instruction manuals from 40 LCUs (20 from leading manufacturers and 20 budget units) were reviewed. Twenty-eight parameters across five categories were assessed using a binary scale (0=incorrect/missing, 1=correct). The categories and their respective evaluation scores were: LCU characteristics (43%), instructions for use (7%), safety precautions (14%), maintenance recommendations (29%), and regulatory certification (7%). These scores were combined to produce a final score. RESULTS: Scores from leading manufacturers ranged between 46-86%, while the budget category ranged from 18-68%. All manuals provided information about the wavelength/spectrum of the LCU. Only Valo X and Valo Cordless reported power values and used the term "irradiance" instead of "intensity." Details such as LED type and active tip emission area were often missing. Instructions on how to use the LCU to photo-cure resins were frequently limited. Although most manuals addressed safety precautions, several lacked details on heat issues and general health precautions. All manuals included maintenance instructions, though information on replacement parts was often missing. Among the LCUs, 85% stated they were CE certified, 32% held both FDA and CE certification, and 63% claimed compliance with ISO and/or IEC standards. CONCLUSIONS: There were notable differences in the completeness and accuracy of the instruction manuals. Manuals from major manufacturers generally provided more comprehensive information than their budget counterparts. CLINICAL SIGNIFICANCE: Instruction manuals should contain accurate information to help clinicians deliver the highest standard of care. The lack of important information about the LCUs in the manuals is concerning.

The impact of Streptococcus mutans biofilms on the color stability and topographical features of three lithium disilicate ceramics.

PURPOSE: Secondary caries around ceramic restorations is the most common reason for the replacement of fixed dental prostheses (FDPs). Therefore, it is important to examine the susceptibility of different ceramic materials to biofilm formation. This study aimed to evaluate biofilm development and associated roughness and color alterations in three lithium disilicate ceramics: Emax CAD (EC), Emax Press (EP), and LiSi Press (LP). MATERIALS AND METHODS: Streptococcus mutans biofilms were grown on the three ceramics (n = 10 per group) for 7 days. Surface roughness values and color alteration were assessed before and after the biofilm using a non-contact profilometer and spectrophotometer, respectively. Biofilm growth was evaluated using colony-forming units (CFUs) and scanning electron microscope (SEM) images. The data were analyzed using one-way ANOVA and Tukey tests. RESULTS: There was a significant (p ≤ 0.001) growth of S. mutans colonies on EC (6.75 ± 0.56) and EP (6.72 ± 0.54) specimens compared to LP, which showed no biofilm growth. The change in average surface roughness (∆Ra, nm) was significantly lower (p < 0.001) in the EC specimens (0.029 ± 0.003) compared to the EP (0.055 ± 0.012) and LP (0.041 ± 0.010). When the changes in the Rv and Rt values were investigated, no significant difference was observed among the groups. Following the biofilm challenge, the change in color (∆E00) was significantly lower (p = 0.005) in the LP group (1.68 ± 1.45) compared to the EC group (3.89 ± 1.50) and no significant difference was observed between the EP group (2.74 ± 1.01) and the other two ceramics (p ≥ 0.05). CONCLUSION: LP ceramics exhibited superior resistance to S. mutans biofilm formation and associated changes in surface roughness and color compared to the Emax CAD and Emax Press ceramics. These findings suggest that the LiSi Press material may be more favorable to mitigate the risk of secondary caries.

Three-dimensional (3D) printing in dental practice: Applications, areas of interest, and level of evidence.

OBJECTIVES: The aim of this review to overview three-dimensional (3D) printing technologies available for different dental disciplines, considering the applicability of such technologies and materials development. MATERIALS AND METHODS: Source Arksey and O'Malley's five stages framework using PubMed, EMBASE, and Scopus (Elsevier) databases managed this review. Papers focusing on 3D printing in dentistry and written in English were screened. Scientific productivity by the number of publications, areas of interest, and the focus of the investigations in each dental discipline were extracted. RESULTS: Nine hundred thirty-four studies using 3D printing in dentistry were assessed. Limited clinical trials were observed, especially in Restorative, endodontics, and pediatric dentistry. Laboratory or animal studies are not reliable for clinical success, suggesting that clinical trials are a good approach to validate the new methods' outcomes and ensure that the benefits outweigh the risk. The most common application for 3D printing technologies is to facilitate conventional dental procedures. CONCLUSIONS: The constantly improving quality of 3D printing applications has contributed to increasing the popularity of these technologies in dentistry; however, long-term clinical studies are necessary to assist in defining standards and endorsing the safe application of 3D printing in dental practice. CLINICAL RELEVANCE: The recent progress in 3D materials has improved dental practice capabilities over the last decade. Understanding the current status of 3D printing in dentistry is essential to facilitate translating its applications from laboratory to the clinical setting.

Inorganic Compounds as Remineralizing Fillers in Dental Restorative Materials: Narrative Review.

Secondary caries is one of the leading causes of resin-based dental restoration failure. It is initiated at the interface of an existing restoration and the restored tooth surface. It is mainly caused by an imbalance between two processes of mineral loss (demineralization) and mineral gain (remineralization). A plethora of evidence has explored incorporating several bioactive compounds into resin-based materials to prevent bacterial biofilm attachment and the onset of the disease. In this review, the most recent advances in the design of remineralizing compounds and their functionalization to different resin-based materials' formulations were overviewed. Inorganic compounds, such as nano-sized amorphous calcium phosphate (NACP), calcium fluoride (CaF2), bioactive glass (BAG), hydroxyapatite (HA), fluorapatite (FA), and boron nitride (BN), displayed promising results concerning remineralization, and direct and indirect impact on biofilm growth. The effects of these compounds varied based on these compounds' structure, the incorporated amount or percentage, and the intended clinical application. The remineralizing effects were presented as direct effects, such as an increase in the mineral content of the dental tissue, or indirect effects, such as an increase in the pH around the material. In some of the reported investigations, inorganic remineralizing compounds were combined with other bioactive agents, such as quaternary ammonium compounds (QACs), to maximize the remineralization outcomes and the antibacterial action against the cariogenic biofilms. The reviewed literature was mainly based on laboratory studies, highlighting the need to shift more toward testing the performance of these remineralizing compounds in clinical settings.

The burden of root caries: Updated perspectives and advances on management strategies.

BACKGROUND: Root caries has gained much attention in the last few years. As the world's population is ageing and people currently tend to retain more teeth compared with older generations, there is an increased prevalence of periodontal disease and gingival recession, which may accelerate the onset of root caries. OBJECTIVE: This review aims to summarise recent findings related to the diagnosis, prevention and treatment of root caries. MATERIALS AND METHODS: MEDLINE (OVID) and Scopus (Elsevier) searches were performed to identify and discuss articles that address the pathogenicity and clinical management of root caries. RESULTS: Root caries is a multifactorial disease. Cariogenic species involved in root caries are less dependent on carbohydrates since collagen degradation inside the dentinal tubules can provide nutrients and microcavities for the invading microorganisms. Furthermore, the root surface has fewer minerals in comparison with enamel, which may accelerate the onset of demineralisation. Root caries could be prevented by patient education, modification of risk factors, and the use of in-office and home remineralisation tools. The use of non-invasive approaches to control root caries is recommended, as the survival rate of root caries restorations is poor. When plaque control is impossible and a deep/large cavity is present, glass ionomer or resin-based restorations can be placed. CONCLUSION: The assessment of root carious lesions is critical to determine the lesion activity and the required intervention. Dental practitioners should also be aware of different prevention and treatment approaches to design optimum oral health care for root caries-affected patients.

Hands-on training based on quantifying radiant exposure improves how dental students cure composites: Skill retention at 2-year follow-up.

INTRODUCTION: The durability and longevity of composite restoration are much dependent on the accurate delivery of the energy required to polymerise the material. This study aimed to investigate the extent to which undergraduate dental students acquire and retain light-curing skills following hands-on training. MATERIALS AND METHODS: Hands-on training comprises faculty tutoring for critical aspects of the light-curing procedure, such as distance and angulation of the light-curing tip. Assessments of the students' ability to deliver a specified radiant exposure to class III and I simulated RBCs using a dental simulator (MARC-PS® ) at three different time points after the training. Data were analysed using repeated measure ANOVA. RESULTS: Immediately after the training, students' performance on curing was improved (p < .05). Overall, the radiant exposure increased after training, but the students lost some of the benefits with time. For curing in the anterior section (anterior sensor-class III), the mean radiant exposure values increased by approximately 20% after the training. After 2 years, the values were 15% greater than baseline values. For curing in the posterior section (posterior sensor-class I), the mean radiant exposure values increased by approximately 150% after the training. A significant decrease (p < .05) was observed; however, the radiant exposure values were still 82% greater than the baseline after 2 years. CONCLUSION: A hands-on training dedicated to light-curing procedures facilitated acquisition and retention up to a 2-year follow-up of skill on how light cure composite inside the mouth. The training was more relevant for curing in posterior areas, where orientation can significantly impact light-curing. A hands-on training where the radiant exposure can be measure gave objective measurement metrics to guide the curing performance. This approach is an effective means of teaching practical skills to dental students.

Light Energy Dose and Photosensitizer Concentration Are Determinants of Effective Photo-Killing against Caries-Related Biofilms.

Caries-related biofilms and associated complications are significant threats in dentistry, especially when biofilms grow over dental restorations. The inhibition of cariogenic biofilm associated with the onset of carious lesions is crucial for preventing disease recurrence after treatment. This in vitro study defined optimized parameters for using a photosensitizer, toluidine blue O (TBO), activated via a red light-emitting diode (LED)-based wireless device to control the growth of cariogenic biofilms. The effect of TBO concentrations (50, 100, 150, and 200 µg/mL) exposed to light or incubated in the dark was investigated in successive cytotoxicity assays. Then, a mature Streptococcus mutans biofilm model under sucrose challenge was treated with different TBO concentrations (50, 100, and 150 µg/mL), different light energy doses (36, 108, and 180 J/cm2), and different incubation times before irradiation (1, 3, and 5 min). The untreated biofilm, irradiation with no TBO, and TBO incubation with no activation represented the controls. After treatments, biofilms were analyzed via S. mutans colony-forming units (CFUs) and live/dead assay. The percentage of cell viability was within the normal range compared to the control when 50 and 100 µg/mL of TBO were used. Increasing the TBO concentration and energy dose was associated with biofilm inhibition (p < 0.001), while increasing incubation time did not contribute to bacterial elimination (p > 0.05). Irradiating the S. mutans biofilm via 100 µg/mL of TBO and ≈180 J/cm2 energy dose resulted in ≈3-log reduction and a higher amount of dead/compromised S. mutans colonies in live/dead assay compared to the control (p < 0.001). The light energy dose and TBO concentration optimized the bacterial elimination of S. mutans biofilms. These results provide a perspective on the determining parameters for highly effective photo-killing of caries-related biofilms and display the limitations imposed by the toxicity of the antibacterial photodynamic therapy's chemical components. Future studies should support investigations on new approaches to improve or overcome the constraints of opportunities offered by photodynamic inactivation of caries-related biofilms.

A Novel Dental Sealant Containing Dimethylaminohexadecyl Methacrylate Suppresses the Cariogenic Pathogenicity of Streptococcus mutans Biofilms.

Cariogenic oral biofilms are strongly linked to dental caries around dental sealants. Quaternary ammonium monomers copolymerized with dental resin systems have been increasingly explored for modulation of biofilm growth. Here, we investigated the effect of dimethylaminohexadecyl methacrylate (DMAHDM) on the cariogenic pathogenicity of Streptococcus mutans (S. mutans) biofilms. DMAHDM at 5 mass% was incorporated into a parental formulation containing 20 mass% nanoparticles of amorphous calcium phosphate (NACP). S. mutans biofilms were grown on the formulations, and biofilm inhibition and virulence properties were assessed. The tolerances to acid stress and hydrogen peroxide stress were also evaluated. Our findings suggest that incorporating 5% DMAHDM into 20% NACP-containing sealants (1) imparts a detrimental biological effect on S. mutans by reducing colony-forming unit counts, metabolic activity and exopolysaccharide synthesis; and (2) reduces overall acid production and tolerance to oxygen stress, two major virulence factors of this microorganism. These results provide a perspective on the value of integrating bioactive restorative materials with traditional caries management approaches in clinical practice. Contact-killing strategies via dental materials aiming to prevent or at least reduce high numbers of cariogenic bacteria may be a promising approach to decrease caries in patients at high risk.

Factors influencing success of radiant exposure in light-curing posterior dental composite in the clinical setting.

PURPOSE: (1) To conduct a comprehensive review of the literature on factors influencing the radiant exposure of resin-based composite (RBC) restorations and (2) To fully understand the appropriate way of using the light curing units (LCUs) to perform restorations with optimal mechanical/physical properties. METHODS: A PubMed search identified recent publications in English that addressed the factors affecting the longevity of the RBC restorations and the optimal usage of LCUs. RESULTS: RBCs require light-induced polymerization of methacrylate monomers present in its composition to reach acceptable mechanical and physical properties. Complete polymerization of the RBC is never reached, and the maximum degree of conversion (DC) varies from 40 to 80%. The amount of radiant exposure (Joules/cm²) required for the commencement of polymerization becomes a core driver for the quality of the RBCs. Insufficient radiant exposure may lead to low strength behavior and susceptibility to degradation, thereby shortening the lifespan of restorations inside the mouth. This suggests that there are factors affecting the radiant exposure during clinical procedures; these factors can be categorized as material-related, LCU-related and operator-related factors. CLINICAL SIGNIFICANCE: Proper light-curing techniques are critical for delivering an adequate amount of radiant exposure to RBCs. Adequate light curing decreases the number of underexposed RBC restorations, improves their mechanical and physical properties and accordingly, increases their clinical longevity.

Delayed Eruption of Maxillary Central Incisors Associated with the Presence of Supernumerary Teeth: A Case Report with 18 Months Follow-up.

AIM: The aim of this study is to discuss a case of an 11-year-old pediatric patient, who was diagnosed with delayed eruption of the permanent maxillary central incisors because of palatally impacted supernumerary teeth. BACKGROUND: The delayed eruption of permanent teeth can be a result of blocking by supernumerary teeth and over-retained primary teeth. Early diagnosis can help in avoiding the complications. The management of such cases depends on the stage of teeth development, teeth position, and space availability. Treatment may combine both surgical and orthodontic interventions. CASE DESCRIPTION: The case was managed by surgically removing the primary retained teeth and supernumerary teeth in two visits then allowing the impacted permanent incisors to erupt without any intervention. CONCLUSION: After 18 months follow-up, the two permanent incisors erupted spontaneously with no orthodontic intervention. CLINICAL SIGNIFICANCE: dentists should be aware of the importance of early diagnosis of supernumerary teeth. The management of such cases should be designed by a multidisciplinary team decision.

Predictors of procedural errors in class II resin composite restorations using bitewing radiographs.

Objective: To identify the potential factors that induce procedural errors during posterior proximal resin composite restorations placed by dental students. Materials and Methods: This retrospective study evaluated 803 bitewing radiographs of posterior proximal resin composite restorations placed by dental students at Imam Abdulrahman bin Faisal University. Atypical radiographic signs of failure were screened, and different patient-, operator-, and clinical-related factors were recorded. Chi-square test was used to examine the relationship between procedural errors and recorded factors. Stepwise adjusted logistic regression model was performed to identify predictors of procedural errors. Results: The most observed errors were internal gaps at the bonding interface and internal voids. Molars had 0.39 the risk of internal voids (odds ratio [OR] = 0.39; confidence interval [CI] = 0.25-0.60; P = <0.0001), 0.41 the risk of sharp angle (OR = 0.41; CI = 0.24-0.68; P = <0.001), and 0.57 the risk of open contact (OR = 0.57; CI = 0.34-0.97; P = 0.04) compared to premolars. Those who were >40 years of age had 1.79 the risk of overhang compared to younger patients (OR = 1.79; CI = 1.04-3.11; P = <0.04). First molars and premolars had 0.64 the risk of overhang compared to second molars and premolars (OR = 0.64; CI = 0.41-1.00; P = 0.04). Junior students had 1.97 the risk of internal gap compared to their senior counterparts (OR = 1.97; CI = 1.20-3.21; P = 0.008). Mesial restorations had 0.38 the risk of external gap compared to mesio-occluso-distal (MOD) restorations (OR = 0.38; CI = 0.19-0.78; P = 0.003). Restorations with a margin coronal to the cemento-enamel junction (CEJ) had 0.44 the risk of external gap compared to those restorations with a margin apical to the CEJ (OR = 0.44; CI = 0.29-0.66; P = <0.0001). Conclusion: Our findings suggested a higher incidence of procedural errors in restoring premolars and MOD cavity preparations. Therefore, it is crucial to enhance the comprehensiveness of laboratory training and expose students to diverse clinical scenarios and various techniques.

Navigating the practical-knowledge gap in deep margin elevation: A step towards a structured case selection - a review.

The deep margin elevation (DME) technique has gained popularity because of numerous supporting case reports. However, some clinicians are cautious regarding using this technique owing to the lack of clear case selection criteria for DME application. This review aimed to analyze case reports and a series of DME cases to determine pre-/post-operative evaluation methods that could be used to suggest a pre-operative case selection checklist for DME. An electronic database search was conducted in June 2021 and updated by June 2023 using selected terms from PubMed, Cochrane Library, Google Scholar, EBSCO, and Scopus. The search was limited to English-language publications and was not restricted to the date. The inclusion criteria were case reports/series addressing periodontal and restorative outcomes of DME. The search identified 217 articles, 76 of which were pertinent. However, only six case reports and one case series satisfied the inclusion criteria. None of the selected studies followed any reporting guidelines, which led to significant information gaps. While the reviewed studies reported favorable outcomes, standardized protocols for evaluating pre-/post-operative restorative and periodontal status were lacking. The post-operative follow-up period varied from 3 months to 6 years. Designing and implementing pre-/post-operative guidelines hold the potential for ensuring the safe application of the DME technique. This may enhance our understanding of the suitability and efficacy of such non-invasive technique in future clinical trials. Clinical significance: Handling deep cavities and preparing crowns are challenging. However, a lack of understanding of when to perform DME can lead to missed opportunities for conservative treatment, thereby a disservice to the patient. Provision of safe guidelines should be employed by clinicians until further evidence either supports or contradicts this treatment method.

Ionic Liquid-Based Silane for SiO2 Nanoparticles: A Versatile Coupling Agent for Dental Resins.

The current longevity of dental resins intraorally is limited by susceptibility to acidic attacks from bacterial metabolic byproducts and vulnerability to enzymatic or hydrolytic degradation. Here, we demonstrate synthesizing an ionic liquid-based antibiofilm silane effective against Streptococcus mutans, a major caries pathogen. Furthermore, we incorporate this silane into dental resins, creating antibiofilm- and degradation-resistant materials applicable across resin types. FTIR, UV-vis, and NMR spectroscopy confirmed the synthesis of the expected ionic liquid-based silane. The characterization of SiO2 after the silanization indicated the presence of the silane and how it interacted with the oxide. All groups achieved a degree of conversion similar to that found for commercial resin composites immediately and after two months of storage in water. The minimum of 2.5 wt % of silane led to lower softening in solvent than the control group (GCTRL) (p < 0.05). While the flexural strength indicated a lower value from 1 wt % of silane compared to GCTRL (p < 0.05), the ultimate tensile strength did not indicate differences among groups (p > 0.05). There was no difference within groups between the immediate and long-term tests of flexural strength (p > 0.05) or ultimate tensile strength (p > 0.05). The addition of at least 5 wt % of silane reduced the viability of S. mutans compared to GCTRL (p < 0.05). The fluorescence microscopy analysis suggested that the higher the silane concentration, the higher the amount of bacteria with membrane defects. There was no difference among groups in the cytotoxicity test (p > 0.05). Therefore, the developed dental resins displayed biocompatibility, proper degree of conversion, improved resistance against softening in solvent, and stability after 6 months of storage in water. This material could be further developed to produce polymeric antimicrobial layers for different surfaces, supporting various potential avenues in developing novel biomaterials with enhanced therapeutic characteristics using ionic liquid-based materials.

Effect of Fiber-Reinforced Composite Placement Site on Fracture Resistance of Premolar Teeth: An in vitro Study.

Background: This study aimed to investigate the fracture behavior of upper premolars with deep MOD cavities that were restored with Ribbond resin-reinforced fibers (FRCs) placed in different orientations. Methods: A total of 54 extracted maxillary premolars were randomly divided into nine groups. The experimental groups underwent MOD cavity preparation with or without root canal treatment, followed by FRCs placed in the pulpal floor, proximal walls, or both. Fracture resistance was tested using an Instron Machine. The samples were visually inspected to analyze the fracture mode. Results: The highest fracture resistance was observed in intact teeth (1299.98 ± 284.66 MPa). Placing Ribbond fibers in the pulpal floor (1155.86 ± 244.21 MPa) or the proximal walls (1077.56 ± 260.60 MPa) significantly improved fracture resistance (p= <0.05), compared to cavities restored with only resin composite (804.58 ± 93.34 MPa). However, placing Ribbond fibers in both the pulpal and proximal walls did not enhance fracture resistance. In the MOD-RCT groups, fracture resistance was improved only when Ribbond fibers were placed in the pulpal floor and the proximal walls. Fracture mode analysis revealed a combined fracture in most of the groups. Conclusion: This study concluded that using FRCs significantly improved the fracture resistance of MOD cavities in premolars and revealed that the placement site could be a determinant factor.

This study investigated the fracture behavior of upper premolars with deep MOD cavities restored with Ribbond resin-reinforced fibers (FRCs) placed in different orientations.Placing Ribbond fibers in the pulpal floor or the proximal walls significantly improved the fracture resistance of premolars with deep MOD cavities.In the MOD-RCT groups, fracture resistance was improved only when Ribbond fibers were placed in the pulpal floor and the proximal walls.Fracture mode analysis revealed a combined fracture in most of the groups. This study concluded that using FRCs significantly improved the fracture resistance of MOD cavities in premolars and revealed that the placement site could be a determinant factor.

Impact of combining dental composite brushes with modeling resins on the color stability and topographic features of composites.

This study explores the effect of using dental brushes with or without metacrylate-based modeling resins on long-term color stability and surface topographies of resin-based composites. This study examined the effects of two variables: (1) the type of brush used (Art brush, Micro-brush, or Mylar strip) and (2) the application of a modeling resin (applied or not applied). The specimens were artificially aged through 10,000 cycles of thermocycling and subsequently immersed in coffee for 30 days. Measurements of color and surface roughness were taken at baseline and after the aging, using a non-contact profilometer for surface roughness and a spectrophotometer for color. Data were analyzed using paired t-tests and one-way ANOVA. Resin-based composites smoothed with dental brushes or micro brushes without modeling resins exhibited lower color change (ΔE) than other groups. Paired t-tests revealed significant differences in average surface roughness (Ra) and valley depth (Rv) for each surfacing technique before and after aging (p ⩽ 0.01). The root means square average of the profile heights (Rq) significantly increased in the control and micro-brush groups (p ⩽ 0.01). In conclusion, the use of brushes in resin-based composites placement does not increase the susceptibility to staining. Instead, the inclusion of resin modeling contributes to discoloration over time.

Multifunctional Dental Adhesives Formulated with Silane-Coated Magnetic Fe3O4@m-SiO2 Core-Shell Particles to Counteract Adhesive Interfacial Breakdown.

The process of bonding to dentin is complex and dynamic, greatly impacting the longevity of dental restorations. The tooth/dental material interface is degraded by bacterial acids, matrix metalloproteinases (MMPs), and hydrolysis. As a result, bonded dental restorations face reduced longevity due to adhesive interfacial breakdown, leading to leakage, tooth pain, recurrent caries, and costly restoration replacements. To address this issue, we synthesized and characterized a multifunctional magnetic platform, CHX@SiQuac@Fe3O4@m-SiO2, to provide several beneficial functions. The platform comprises Fe3O4 microparticles and chlorhexidine (CHX) encapsulated within mesoporous silica, which was silanized by an antibacterial quaternary ammonium silane (SiQuac). This platform simultaneously targets bacterial inhibition, stability of the hybrid layer, and enhanced filler infiltration by magnetic motion. Comprehensive experiments include X-ray diffraction, FT-IR, VSM, EDS, N2 adsorption-desorption (BET), transmission electron microscopy, scanning electron microscopy, thermogravimetric analysis, and UV-vis spectroscopy. Then, CHX@SiQuac@Fe3O4@m-SiO2 was incorporated into an experimental adhesive resin for dental bonding restorations, followed by immediate and long-term antibacterial assessment, cytotoxicity evaluation, and mechanical and bonding performance. The results confirmed the multifunctional nature of CHX@SiQuac@Fe3O4@m-SiO2. This work outlined a roadmap for (1) designing and tuning an adhesive formulation containing the new platform CHX@SiQuac@Fe3O4@m-SiO2; (2) assessing microtensile bond strength to dentin using a clinically relevant model of simulated hydrostatic pulpal pressure; and (3) investigating the antibacterial outcome performance of the particles when embedded into the formulated adhesives over time. The results showed that at 4 wt % of CHX@SiQuac@Fe3O4@m-SiO2-doped adhesive under the guided magnetic field, the bond strength increased by 28%. CHX@SiQuac@Fe3O4@m-SiO2 enhanced dentin adhesion in the magnetic guide bonding process without altering adhesive properties or causing cytotoxicity. This finding presents a promising method for strengthening the tooth/dental material interface's stability and extending the bonded restorations' lifespan.

The demineralization resistance and mechanical assessments of different bioactive restorative materials for primary and permanent teeth: an in vitro study.

OBJECTIVES: This article examines the efficacy of two bioactive dental composites in preventing demineralization while preserving their mechanical and physical properties. MATERIALS AND METHODS: The study compares Beautifil Kids and Predicta® Bioactive Bulk-Fill (Predicta) composites with conventional dental composite. Flexural strength and elastic modulus were evaluated using a universal testing machine. A pH-cycling model assessed the composites' ability to prevent dentin demineralization. Color stability and surface roughness were measured using a spectrophotometer and non-contact profilometer, respectively, before and after pH-cycling, brushing simulation, and thermocycling aging. RESULTS: Beautifil Kids exhibited the highest flexural strength and elastic modulus among the materials (p < 0.05). Predicta demonstrated the highest increase in dentin surface microhardness following the pH-cycling model (p < 0.05). All groups showed clinically significant color changes after pH-cycling, with no significant differences between them (p > 0.05). Predicta exhibited greater color change after brushing and increased surface roughness after thermocycling aging (p < 0.05). While Beautifil Kids had higher surface roughness after pH-cycling (p < 0.05). DISCUSSION/CONCLUSION: Bioactive restorative materials with ion-releasing properties demonstrate excellent resistance to demineralization while maintaining mechanical and physical properties comparable to the control group.

Effect of eucalyptus oil on Streptococcus mutans and Enterococcus faecalis growth.

OBJECTIVES: There is a significant apprehension in medicine and dentistry concerning the emergence of antibiotic-resistant pathogens, as it composes a significant threat to global health, particularly oral health. The growing concern that oral pathogens may develop resistance against standard preventive measures raises the need for alternative measures to prevent these pathogens' growth without inducing microbial resistance. Therefore, this study aims to assess the antibacterial properties of eucalyptus oil (EO) against two main oral disease pathogens, Streptococcus mutans, and Enterococci faecalis. METHODS: S. mutans and E. faecalis biofilms were initiated using brain-heart infusion (BHI) broth supplemented with 2% sucrose with and without diluted EO. After 24 h of biofilm formation, total absorbance was measured via spectrophotometer; then, the biofilm was fixed, stained with crystal violet dye, and measured at 490 nm. An Independent t-test was used to compare the outcomes. RESULTS: Diluted EO revealed significant total absorbance reduction against S. mutans and E. faecalis compared to the control (p ≤ 0.001). For the biofilm measurement, S. mutans and E. faecalis biofilms were reduced by around 60- and 30-fold, respectively, compared to the group with no EO (p ≤ 0.001). CONCLUSION: Based on this study's results, using EO as an organic compound could be considered an adjunctive tool in preventing the growth of oral pathogens causing dental caries and endodontic infection.

Recurrent caries models to assess dental restorations: A scoping review.

OBJECTIVES: To review the literature on recurrent caries models used to evaluate restorative materials, compare reported methodology and parameters, and devise specific recommendations to be considered in future investigations. DATA: The following were extracted: study design, sample characteristics, source of teeth, name of restorations compared including controls, recurrent caries model type, type of demineralizing and remineralizing solutions, type of biofilm used, methods to detect recurrent caries. SOURCES: Literature searches were performed in OVID Medline, EMBASE, SCOPUS, and Cochrane Library. STUDY SELECTION: For a study to be included, it had to examine dental materials for tooth restoration purposes only with a valid control group and evaluate restorative dental materials regardless of the form of the teeth caries model used or nature of the tooth structure used. A total of 91 studies were included. Most of the studies presented were in vitro. Human teeth were the main source of specimens utilized. Around 88% of the studies used specimens without an artificial gap, and 44% used a chemical model. S. mutans was the main bacterial species used in microbial caries models. CONCLUSION: The findings of this review provided an insight into the performance of available dental materials assessed using different recurrent caries models, yet this review cannot be used as a guideline for material selection. Selecting the appropriate restorative material relies on several patient-related factors such as microbiota, occlusion, and diet that are not comprehensively taken into consideration in recurrent caries models and thus hinder reliable comparison. CLINICAL SIGNIFICANCE: Due to the heterogenicity of variables among studies on the performance of dental restorative materials, this scoping review aimed to provide insights for dental researchers concerning the available recurrent caries models, testing methods used, and aspects of comparison between these materials including their characteristics and limitations.

The Effect of Salbutamol and Budesonide Pediatric Doses on Dental Enamel and Packable and Flowable Composites: Microhardness, Surface Roughness and Color.

OBJECTIVE: To assess and compare the effects of two pediatric anti-asthmatic medication doses on the microhardness of enamel and microhardness, surface roughness and color of restorative materials. METHODS: Human enamel samples and packable and flowable composite restorations were used. The samples were exposed to Salbutamol (0.6 mL/6 mL saline) and Budesonide (2 mL/2 mL saline) via a custom-made chamber connected to a nebulizer. Medication administration was conducted for 10 days. The samples were brushed with an electronic brush in a continuous and circular mode for 10 s after 10 min of medication administration. Assessments of microhardness, surface roughness and color were carried out at three different time intervals: baseline (T0), 5 days (T1) and 10 days (T2). One-way analysis of variance (ANOVA), a two-sample t-test and a Bonferroni multiple comparison test were used to analyze the data and compare between the groups. RESULTS: Both medications significantly (p < 0.05) decreased the microhardness of the enamel and composite samples after 10 days. Both medications lowered the surface roughness of both types of composite with a greater effect observed after 10 days of Budesonide administration (p < 0.05). Both medications had comparable detectable color change on both types of composite with a greater effect observed after 10 days of Budesonide administration (p < 0.05). CONCLUSION: Salbutamol and Budesonide significantly decreased microhardness in the enamel samples. Both medications affected the properties of packable and flowable composites. The packable composite showed more resistance to microhardness changes. Both medications showed a clinically detectable change in the color of packable and flowable composites.