Impact of material selection, processing protocol and aging on the flexural strength of lithium silicate ceramics.

Ensuring stable soft tissue sealing at the transgingival zone of titanium (Ti) abutments is critical for long-term implant success, yet conventional Ti abutment surfaces lack intrinsic antibacterial functionality. Here, a multifunctional antibacterial coating was developed by immobilizing pH-responsive nanorods (NRs) composed of tanshinone IIA (TA), lactoferrin (LF), and sodium alginate (SA) onto a polydopamine-modified (PDA) Ti surface. The resulting Ti&PDA@NRs coating achieved a high TA loading capacity through synergistic electrostatic adsorption and covalent crosslinking. The coating exhibited pH-modulated release behavior, characterized by accelerated TA release under acidic conditions and sustained release at physiological pH. Antibacterial evaluations using representative oral bacterial species demonstrated effective inhibition of bacterial adhesion and biofilm formation via surface-mediated contact killing, while released TA further suppressed free bacteria, confirming a dual-mode antibacterial mechanism. Mechanistic studies indicated that antibacterial activity was associated with bacterial membrane disruption accompanied by elevated intracellular reactive oxygen species (ROS) generation. Cytocompatibility assessments using human gingival fibroblasts and NIH/3T3 cells under both normal and inflammatory conditions confirmed low cytotoxicity. Moreover, the coating maintained good stability and sustained TA retention under simulated oral conditions. Collectively, this work presents a clinically relevant antibacterial surface strategy for mitigating implant-associated bacterial challenges in the transgingival region.

To compare the efficacy of resin-based sealants (RBS) and glass-ionomer sealants (GIS) with varying viscosities on retention, fissure penetration and occlusal caries inhibition under simulated oral conditions. Extracted human third molars were randomly assigned to five groups: high-viscosity GIS (Group 1), medium-viscosity GIS (Group 2), low-viscosity GIS (Group 3), RBS (Group 4), and no sealant (Group 5, negative control). Sealant retention was evaluated visually after 37 °C water storage and thermocycling of 10,000 cycles between 5 and 55°C with a dwell time of 20s, whilst penetration depth was assessed using scanning electron microscopy (SEM). Mineral density changes (ΔMDV) following pH cycling for 21 days and bacterial challenge with Streptococcus mutans for 7 days were quantified using micro-CT scans. Statistical analysis included Kruskal-Wallis tests, Mann-Whitney U tests with Bonferroni correction, Chi-square tests, Spearman's correlation, and multiple linear regression analyses. All sealants exhibited optimal retention (> 83% fully intact) without significant differences (p = 0.494). RBS demonstrated superior penetration (median: 100%), significantly higher than high-viscosity GIS (median: 90.5%, p = 0.003). RBS also provided the greatest protection against mineral loss under both pH cycling (IQR: 0.0252) and bacterial challenges (IQR: 0.0349), exhibiting significantly lower ΔMDV compared to majority of the GIS groups and the negative control (p < 0.001). No significant correlation was observed between sealant penetration or retention and ΔMDV outcomes. All sealants showed effective retention and penetration capabilities; however, the RBS provided superior caries inhibition compared to glass-ionomer alternatives. The effectiveness of GIS was comparable amongst varying viscosities.

Recently developed bioactive and reinforced glass ionomer cement (GIC) formulations may offer improved resistance to acid and mechanical wear compared to conventional formulations. Yet, comparative evidence under simulated oral conditions remains limited. This study evaluated the effect of erosive and erosive-abrasive challenges on the surface properties of five GIC-based restorative materials: Riva Self Cure (RS), Zirconomer Improved (ZI), Fuji II LC (FII), Equia Forte HT Fil + Equia Forte Coat (EQ), and ACTIVA BioACTIVE Restorative (AC). Standardized specimens from each material were immersed in artificial saliva, citric acid, or citric acid combined with simulated brushing. Surface roughness (Ra and Rq, µm) was measured, followed by qualitative surface characterization using scanning electron microscopy (SEM). Both material type and treatment condition significantly affected Ra and Rq values, with a significant interaction (p < 0.001). Erosive and erosive-abrasive challenges significantly increased surface roughness for all materials (p < 0.001). AC consistently exhibited the lowest values across all conditions, while ZI and RS showed the highest roughness, particularly under erosive-abrasive challenge. FII and EQ demonstrated intermediate performance. SEM observations corroborated profilometric findings, revealing material-dependent degradation patterns. All materials showed increased roughness following erosive and erosive-abrasive exposure. However, AC showed a comparatively more favorable profile than the other materials.

• Novel comparison of α, α + β, and β titanium alloys in artificial saliva and Coca-Cola for dental implant applications. • Balancing mechanical integrity, corrosion resistance, and biological response is essential for bone implant materials. • Loose sintering produces porous implants with enhanced bioactivity but reduced corrosion resistance. • Low-modulus Ti35Nb7Zr5Ta alloy exhibits superior bioactivity compared with cpTi IV and Ti6Al4V. • Acidic dietary habits significantly increase corrosion rates in all titanium alloys studied. Commercially pure titanium (cpTi IV) and Ti6Al4V are widely used in dental implants due to their good mechanical properties and clinical reliability. However, their high elastic modulus may cause biomechanical mismatch with bone, and Ti6Al4V contains potentially cytotoxic elements such as Al and V. Additionally, exposure to acidic carbonated beverages may compromise implant longevity by accelerating corrosion. This study compares the biomechanical (stiffness and strength) and biofunctional (corrosion resistance and bioactivity) performance of cpTi IV and Ti6Al4V with a commercial Ti35Nb7Zr5Ta alloy, which features a lower elastic modulus and lacks cytotoxic elements. Although promising, Ti35Nb7Zr5Ta is more costly and requires more complex processing, warranting detailed evaluation. Disc-shaped samples were produced by loose sintering and fully dense processing to assess the influence of porosity. Corrosion behavior was analyzed using open circuit potential, electrochemical impedance spectroscopy, and potentiodynamic polarization in artificial saliva and Coca-Cola at 37 °C. Results show superior corrosion resistance for cpTi IV, balanced mechanical–corrosion behavior for Ti6Al4V, and improved biomechanical compatibility and bioactivity for Ti35Nb7Zr5Ta. Porosity and acidic conditions negatively affected passive film stability. These findings support optimization of titanium-based dental and orthopedic implants.

Quantitative evaluation of release behavior of synthetic taste-masking drugs using polysaccharide-based carrier with direct analysis in real-time mass spectrometry

Aromatic compounds constitute the primary chemical components responsible for the distinctive flavor characteristics of cigars and play a pivotal role in cigar quality assessment. This study employed solid-phase microextraction/gas chromatography-mass spectrometry (SPME/GC-MS) and liquid-liquid extraction/gas chromatography-mass spectrometry (LLE/GC-MS) to analyze the aroma profiles of Chinese and international cigars under smoking and simulated oral environment conditions. Based on multidimensional statistical and model evaluations-including One-way analysis of variance (P ≤ 0.05), odor activity threshold (OAV ≥ 1), variable importance in projection (VIP ≥ 2), and fold change (≥ 1.5)-six key aromatic compounds were identified as significant contributors to the characteristic flavor of Chinese cigars: methylpyrazine, tabanone, 3-methylbutyric acid, limonene, 2,6-dimethylphenol, and malic acid. To elucidate the sensory perception mechanisms of these compounds, molecular dynamics simulations were conducted to investigate interactions between the human oral cavity receptor T1R1 and the identified aromatic compounds. The results revealed that 2,6-dimethylphenol, 3-methylbutyric acid, malic acid, and methylpyrazine exhibited specific binding interactions with the T1R1 receptor. These molecular interactions are hypothesized to facilitate receptor-mediated perception of the compounds in the oral environment, thereby contributing to the overall sensory experience of Chinese cigar.

Oral health hinges on tightly regulated acid-base chemistry that fluctuates within minutes after eating or hygiene, yet existing assessments are episodic and miss these transient events. We demonstrate a liquid-permeable potentiometric pH sensor designed for non-invasive intraoral monitoring that integrates a saliva-through fibrous layer for fast convective-capillary transport, a percolated silver-nanowire network for low-impedance readout and antibacterial activity, and a pH-responsive sensing layer paired with an on-board Ag/AgCl reference. The integration sensor delivers near-Nernstian sensitivity, rapid and reversible responses, and low drift during extended operation under simulated oral conditions. Microbiological assays show the inhibition of Streptococcus mutans and Candida albicans, supporting resistance to biofilm fouling. Moreover, in human-use demonstrations, the sensor captures real-time salivary pH excursions during sugar intake, mixed meals, and tooth brushing. This platform establishes a practical route toward patient-centric oral electronics that shift diagnosis and prevention from the clinic into everyday life.

Glass ionomer-based restorative materials are widely used in pediatric dentistry because of their chemical adhesion to tooth structure, ion-releasing capacity, and clinical handling advantages; however, their mechanical durability under simulated oral aging conditions remains a critical factor influencing long-term clinical performance. This in vitro study aimed to evaluate and compare the surface microhardness of three contemporary glass ionomer-based restorative materials-Beautifil Bulk Restorative, EQUIA Forte HT, and Fuji II LC-before and after thermocycling. A total of 90 disc-shaped specimens (10 mm in diameter and 2 mm in thickness) were prepared, with 30 samples allocated to each material group. Microhardness measurements were performed using the Vickers hardness test at baseline and after 10,000 thermocycling cycles between 5 °C and 55 °C to simulate intraoral aging. Results were expressed as the mean ± standard deviation, and statistical analyses were conducted using non-parametric tests. Thermocycling resulted in a statistically significant reduction in microhardness values for all tested materials (p < 0.05). Beautifil Bulk Restorative exhibited the highest microhardness values both before and after thermocycling, followed by Fuji II LC and EQUIA Forte HT, with significant differences observed among all groups (p < 0.001). Within the limitations of this study, Beautifil Bulk Restorative may be considered a favorable option for restorations in young permanent teeth, whereas EQUIA Forte HT, exhibiting lower microhardness values, may be more suitable for primary teeth, where physiological wear is expected.

Studying surface energy and permeability offers insights into the relationship between temporary polymers and the oral environment. Variations in contact angle and surface free energy may signify modifications in surface polarity and tendency for plaque buildup, staining, or microcrack formation. Objectives: The present study aims to evaluate the influence of simulated salivary and chemical aging conditions on the surface and mechanical properties of 3D-printed PMMA provisional materials. Methods: Two 3D-printed polymethyl methacrylate (PMMA) resins were investigated, namely Anycubic White (Anycubic, Shenzhen, China) and NextDent Creo (NextDent, 3D Systems, Soesterberg, The Netherlands), using two aging protocols. Protocol A consisted of chemical aging in an alcohol-based mouthwash, while Protocol B involved thermal aging in artificial saliva. After aging, surface properties (wettability and SFE) and compressive behaviour were analyzed. Statistical analysis was conducted to assess the influence of temperature, immersion duration, and aging medium, with significance established at p < 0.05. Results: In Protocol A, mechanical properties showed a time-dependent decrease, with material-specific stabilization trends. In Protocol B, thermal aging resulted in elastic modulus reductions ranging from 35% to 46% relative to the reference. The yield strength exhibited similar tendencies. In Protocol A, X samples exhibited a consistent decline, while C samples stabilized after 14 days. For Protocol B, the fitted model produced residuals under 2%, confirming temperature as the primary variable. Conclusions: Chemical and thermal aging influence the physical and mechanical properties of the analyzed 3D-printed PMMA. Among the two protocols, thermal aging in artificial saliva resulted in more pronounced material degradation. After chemical aging in mouthwash, the surface free energy remained almost constant. After thermal aging, all samples demonstrated a gradual rise in SFE with prolonged immersion duration. The current study offers valuable insights into the environmental stability of printed PMMA; however, it is an in vitro evaluation. The findings indicate that temperature exposure and prolonged contact with oral hygiene products may affect the mechanical reliability of 3D-printed provisional restorations, which must be considered during material selection for longer temporary usage. Additionally, spectroscopic and microscopic analyses might better clarify the molecular-level chemical alterations linked to aging.

To investigate the effects of artificial aging on the mechanical, physical, and chemical characteristics of polymethyl methacrylate (PMMA) denture base materials. This systematic review and meta-analysis of in vitro studies searched five databases until December 2025. This was reported in accordance with the preferred reporting items for systematic reviews and meta-analyses 2020 (PRISMA 2020) guidelines. Selected studies evaluated heat-cured, computer-aided design/computer-aided manufacturing (CAD/CAM)-milled, and three-dimensionally (3D)-printed PMMA denture base materials. All these used artificial aging protocols. Random-effects meta-analysis was applied wherever necessary. Artificial aging resulted in a significant decrease in flexural strength after aging. There were small to moderate decreases in mean values based on fabrication method and aging protocol applied. Computer-aided design/computer-aided manufacturing-milled PMMA consistently showed the highest flexural strength values before and after aging. Hardness and roughness were not affected by standard thermocycling protocols. There was some variability with coffee or staining aging protocols. Three-dimensionally printed PMMA showed higher water sorption values than milled or conventional PMMA. The levels of residual monomer released were low for all fabrication techniques. Artificial aging resulted in small to moderate decreases in the flexural strength of PMMA denture base materials. Computer-aided design/computer-aided manufacturing-milled PMMA showed the least change with aging. Three-dimensionally printed PMMA exhibited the greatest change. Denture base material selection should account for the method of fabrication and expected aging effects, especially in patients with high denture loading. How to cite this article: Aldosari LIN. Degradation of Printed Polymethyl Methacrylate Denture Base Materials under Simulated Oral Conditions: A Systematic Review and Meta-analysis. J Contemp Dent Pract 2026;27(1):92-103.

Aesthetic demands in contemporary dentistry have driven the widespread adoption of clear aligners (CAs), yet their polymeric substrates lack intrinsic antibacterial and anti-inflammatory functionality, predisposing the periodontium to inflammation during prolonged wear. Here, we present a multifunctional surface coating for PETG-based CAs, comprising dopamine-grafted TEMPO-oxidized bacterial cellulose nanofibers (TOBC-DA), curcumin (Cur), and polyvinyl alcohol (PVA), applied via a facile spin-coating process. TOBC-DA serves as a bioadhesive matrix that forms a robust, long-lasting bond with PETG while maintaining chemical stability in simulated oral conditions. Incorporation of Cur endows the coating with potent antibacterial and anti-inflammatory activity, and PVA enhances Cur solubility to ensure uniform film formation. The resulting composite layer-measuring under 5 μm in thickness-preserves the optical transparency, dimensional fidelity, and mechanical integrity of PETG. Structurally, the cross-linked TOBC-DA network and PVA backbone confer enhanced wear resistance and fracture resistance without compromising flexibility. Functionally, the hydrophilic surface repels early colonizers such as P. gingivalis, while sustained Cur release disrupts bacterial cell membranes and downregulates pro-inflammatory mediators (IL-6, TNF-α, MMP-9) in periodontal tissues. This work demonstrates a clinically translatable coating strategy that integrates aesthetic preservation with active periodontal protection, offering a promising route to improve oral health outcomes during CAs therapy.

Influence of Dentine Thickness and Intraradicular Reinforcement on Fracture Resistance of MTA-apexified Immature Anterior Teeth.

Direct oil structuring using engineered whey protein particles: Rheological characterization and application in chocolate formulation.

PurposeTo investigate the impact of common dental hygiene practices, including brushing with fluoridated toothpaste, on titanium implant surfaces with varying degrees of roughness, both in the presence and absence of citric acid.MethodsTitanium (Ti) disks with varying surface roughness (smooth and moderately rough, n = 80) were divided into two groups. Different treatments were applied to each group: control (no treatment, SC, RC), citric acid exposure (S1, R1), citric acid exposure followed by brushing (S2, R2), and citric acid exposure followed by brushing with fluoridated toothpaste (S3, R3). Surface roughness (Ra) was measured using a stylus profilometer and scanning electron microscopy (SEM) was used to examine surface morphology and potential damage. ANOVA associated with the Tukey’s tests were used to compare Ra between the groups.ResultsSmooth Ti surfaces exhibited minimal changes in roughness following various treatments, including citric acid exposure, brushing, and fluoride treatment, with % of change in Ra ranging from 0.43 to 7.1% compared to the control. However, SEM analysis revealed surface alterations such as chipping and scratching. In contrast, rough Ti surfaces showed significant increases in roughness after treatments, with the combination of citric acid and brushing (R1 and R2) causing the most pronounced effects with a 48.8% change in Ra compared to the control. Fluoride treatment may have mitigated these effects to some extent.ConclusionsThe common dental hygiene practices, such as brushing with fluoridated toothpaste and exposure to acidic substances, can significantly impact the surface topography of Ti implants, particularly those with rough surfaces.

Effect of cinnamaldehyde on rheological, physicochemical, and structural properties of mung bean protein/low methoxyl pectin-based emulsion gels as a delivery system of vitamin D3 for dysphagia.

Ions released from denture base resins under oral conditions may affect biocompatibility and material stability, particularly at low pH. This study quantified inorganic ion release from three denture base resins—conventional heat-cured PMMA, pre-polymerised CAD/CAM-milled PMMA, and a 3D-printed resin—under simulated oral conditions. Disc specimens (n = 3 per group) were immersed in artificial saliva at pH 4.0 or 7.0 (37 °C) for 24 h or 30 d. Eluates were analysed for Ca, K, Mg, Na, Ti, Fe (ICP-OES) and Zn, Ni, Cu, Cr, Cd, Pb (ICP-MS). Solution concentrations are reported in mg L−1 or µg L−1; cumulative release is normalised per g of resin (mg g−1). Ca, Na, K, Mg, Zn, Ni, Cu, Cr, Fe and Ti were detected; Cd and Pb were below the detection limit. After 30 d at pH 4.0, total release ranked: conventional ≈ 2.8 mg g−1 &gt; 3D-printed ≈ 1.2 mg g−1 &gt; CAD/CAM ≈ 0.6 mg g−1; values were lower at pH 7.0. Material and pH significantly affected most ions (p &lt; 0.001), whereas time affected only Na. Metals were in the µg L−1 range (Ni ≈ 0.008 mg L−1). CAD/CAM showed the lowest total release, consistent with higher chemical stability under simulated oral conditions; 3D-printed was intermediate, and conventional PMMA the highest.

studies have shown that while both materials perform well in esthetic restorations, their effectiveness in minimizing microleakage depends heavily on the placement technique used. 5However, there is no consensus on whether nano-hybrids or giomers provide better marginal sealing in challenging clinical situations.Placement techniques play a crucial role in mitigating microleakage.Bulk-fill techniques, while time-efficient, often result IntroductIonEsthetic dental treatment has become the most important concern of patients today. 1 Dentistry focuses on removing bacterial and diseased tissue, and restoring tooth function and esthetics through appropriate restorative materials. 2 In class V restorations, microleakage remains a significant issue, particularly since the gingival margins are often placed on dentin or cementum.Due to its low mineral content and complex structure, it is more difficult to bond to the dentin surface than to enamel. 3 Various factors influence microleakage, including cavity shape, restorative materials, and placement techniques, all of which aim to lower the configuration factor (C-factor) to minimize stress due to polymerization shrinkage. 4Though many approaches have been tested for restoring the cervical restorations, discrepancies in outcomes exist due to differences in material composition, techniques, and absence of standardization in evaluation. 5 The introduction of thermocycling and dye penetration techniques has further enhanced the evaluation of microleakage under simulated oral conditions. 6icrohybrid (G-aenial Posterior, GC, Tokyo, Japan), a nano-hybrid resin, is known for its superior handling characteristics and reduced polymerization shrinkage.Similarly, giomer (Beautiful II, Shofu Inc, Japan), a giomer-based composite, exhibits fluoride-releasing properties and enhanced marginal adaptability.

Biocompatibility and cytotoxic effects of myofunctional appliance materials on human periodontal ligament fibroblasts

Evaluation of the shear bond strength of surface-treated cobalt-chromium metal crowns on Corticobasal® implant abutments cemented using different luting agents.